:root {
    --ink: #10233f;
    --muted: #62738c;
    --line: #d8e6f5;
    --soft: #f3f8ff;
    --panel: #ffffff;
    --dark: #173b75;
    --dark-2: #dcecff;
    --green: #2563eb;
    --green-2: #38bdf8;
    --blue: #2f80ed;
    --gold: #d99a21;
    --danger: #c2410c;
    --site-shell-width: 1920px;
    --site-shell-gutter: clamp(40px, 6vw, 128px);
}

/* Operational experience phase 1 */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.nav-menu-button {
    display: none;
    width: 38px;
    height: 38px;
    padding: 9px;
    border: 1px solid var(--line);
    border-radius: 6px;
    background: #fff;
    cursor: pointer;
}

.nav-menu-button span {
    display: block;
    width: 18px;
    height: 2px;
    margin: 3px 0;
    background: var(--ink);
}

.nav-account {
    position: relative;
    display: flex;
    align-items: center;
}

.nav-account-trigger {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    padding: 5px;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 999px;
    color: var(--ink);
    background: #f5f9ff;
    font: inherit;
    cursor: pointer;
    transition: border-color 0.18s ease, background 0.18s ease, box-shadow 0.18s ease;
}

.nav-account-trigger:hover,
.nav-account-trigger:focus-visible,
.nav-account.is-open .nav-account-trigger {
    border-color: rgba(47, 128, 237, 0.42);
    background: #fff;
    box-shadow: 0 8px 22px rgba(32, 73, 128, 0.12);
    outline: none;
}

.nav-account-avatar {
    display: inline-flex;
    flex: 0 0 auto;
    width: 30px;
    height: 30px;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    color: #fff;
    background: linear-gradient(135deg, var(--blue), var(--green-2));
    font-size: 0.82rem;
    font-weight: 900;
}

.nav-account-copy {
    display: grid;
    min-width: 0;
    text-align: left;
    line-height: 1.2;
}

.nav-account-copy strong {
    max-width: 128px;
    overflow: hidden;
    color: var(--ink);
    font-size: 0.82rem;
    font-weight: 900;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.nav-account-copy small {
    margin-top: 2px;
    color: var(--muted);
    font-size: 0.7rem;
    font-weight: 700;
}

.nav-account-menu {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    z-index: 20;
    display: grid;
    min-width: 190px;
    padding: 8px;
    border: 1px solid var(--line);
    border-radius: 10px;
    background: #fff;
    box-shadow: 0 18px 42px rgba(32, 73, 128, 0.16);
}

.nav-account-menu[hidden] {
    display: none;
}

.nav-account-status {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    margin-bottom: 5px;
    padding: 7px 10px 10px;
    border-bottom: 1px solid var(--line);
    cursor: default;
}

.nav-account-status span {
    color: var(--muted);
    font-size: 0.75rem;
    font-weight: 700;
}

.nav-account-status strong {
    color: var(--blue);
    font-size: 0.8rem;
    font-weight: 900;
}

.nav-account-menu a,
.nav-account-menu .nav-logout {
    width: 100%;
    padding: 9px 10px;
    border-radius: 6px;
    color: var(--ink);
    font-size: 0.84rem;
    font-weight: 800;
    line-height: 1.4;
    text-align: left;
}

.nav-account-menu a:hover,
.nav-account-menu a:focus-visible,
.nav-account-menu .nav-logout:hover,
.nav-account-menu .nav-logout:focus-visible {
    color: var(--blue);
    background: #edf5ff;
    outline: none;
}

.nav-account-logout-form {
    margin-top: 5px;
    padding-top: 5px;
    border-top: 1px solid var(--line);
}

.nav-logout {
    padding: 0;
    border: 0;
    background: transparent;
    font: inherit;
    cursor: pointer;
}

.logout-form { margin: 0; }

.mobile-account-panel {
    display: none;
}

.learning-step {
    color: inherit;
    transition: background 0.18s ease, transform 0.18s ease;
}

.learning-step:hover,
.learning-step:focus-visible {
    background: #f7fbff;
    transform: translateY(-2px);
}

.course-catalog-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 28px;
    align-items: start;
}

.course-chapter-list {
    display: grid;
    gap: 10px;
}

.course-chapter-item {
    display: grid;
    grid-template-columns: 56px minmax(0, 1fr) auto;
    gap: 16px;
    align-items: center;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    transition: border-color 0.18s ease, box-shadow 0.18s ease, transform 0.18s ease;
}

.course-chapter-item:hover,
.course-chapter-item:focus-visible {
    border-color: rgba(47, 128, 237, 0.42);
    box-shadow: 0 14px 30px rgba(47, 95, 150, 0.1);
    transform: translateY(-2px);
}

.course-chapter-number {
    color: var(--blue);
    font-size: 1.5rem;
    font-weight: 900;
}

.course-chapter-copy {
    display: grid;
    gap: 4px;
}

.course-chapter-copy strong {
    font-size: 1.05rem;
}

.course-chapter-copy span,
.course-summary-panel p {
    color: var(--muted);
}

.course-chapter-access {
    color: var(--blue);
    font-size: 0.82rem;
    font-weight: 900;
}

.course-chapter-access.is-locked {
    color: #9a6700;
}

.course-summary-panel,
.course-reader-sidebar,
.course-reader-content,
.empty-state,
.membership-plan-card {
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
}

.course-summary-panel {
    position: sticky;
    top: 88px;
    padding: 22px;
}

.course-summary-panel h2 {
    margin: 12px 0 8px;
    font-size: 1.25rem;
}

.course-summary-panel a {
    display: inline-flex;
    margin-top: 14px;
    color: var(--blue);
    font-weight: 900;
}

.course-reader-section {
    padding: 32px 0 64px;
}

.course-reader-layout {
    display: grid;
    grid-template-columns: 280px minmax(0, 1fr);
    gap: 22px;
    align-items: start;
}

.course-reader-sidebar {
    position: sticky;
    top: 88px;
    padding: 18px;
}

.course-reader-sidebar > strong {
    display: block;
    margin: 14px 0;
    font-size: 1rem;
}

.course-back-link {
    color: var(--blue);
    font-size: 0.82rem;
    font-weight: 900;
}

.course-reader-sidebar nav {
    display: grid;
    gap: 5px;
    max-height: calc(100vh - 190px);
    overflow-y: auto;
    overscroll-behavior: contain;
    padding-right: 4px;
    scrollbar-gutter: stable;
}

.course-reader-sidebar nav a {
    display: grid;
    grid-template-columns: 28px minmax(0, 1fr) auto;
    gap: 8px;
    padding: 9px;
    border-radius: 6px;
    color: var(--muted);
    font-size: 0.84rem;
}

.course-reader-item-title {
    display: -webkit-box;
    min-width: 0;
    overflow: hidden;
    line-height: 1.4;
    overflow-wrap: anywhere;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
    line-clamp: 2;
}

.course-reader-sidebar nav a.active,
.course-reader-sidebar nav a:hover,
.course-reader-sidebar nav a:focus-visible {
    color: var(--blue);
    background: #edf5ff;
}

.course-reader-sidebar small {
    color: #9a6700;
}

.course-reader-content {
    padding: 34px;
}

.course-reader-head {
    padding-bottom: 24px;
    border-bottom: 1px solid var(--line);
}

.course-reader-head h1 {
    margin: 12px 0 8px;
    font-size: clamp(1.75rem, 3vw, 2.5rem);
    line-height: 1.2;
}

.course-reader-head p {
    margin: 0;
    color: var(--muted);
}

.course-chapter-body {
    padding: 28px 0;
    border: 0;
    box-shadow: none;
}

.course-chapter-body > h1:first-child {
    display: none;
}

.course-reader-pager {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    padding-top: 24px;
    border-top: 1px solid var(--line);
}

.course-reader-pager a {
    display: grid;
    gap: 3px;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: 8px;
}

.course-reader-pager a.next {
    text-align: right;
}

.course-reader-pager span {
    color: var(--muted);
    font-size: 0.78rem;
}

.empty-state {
    padding: 24px;
    color: var(--muted);
}

.empty-state strong {
    display: block;
    color: var(--ink);
    font-size: 1.05rem;
}

.empty-state p {
    margin: 6px 0 0;
}

.empty-state .button {
    margin-top: 16px;
}

.search-summary {
    display: flex;
    gap: 12px;
    align-items: baseline;
    margin: 20px 0 12px;
}

.search-summary span {
    color: var(--muted);
}

.success-message {
    margin: 12px 0 0;
    padding: 8px 10px;
    border: 1px solid rgba(22, 163, 122, 0.28);
    border-radius: 6px;
    color: #0f765c;
    background: #ecfdf5;
    font-weight: 800;
}

.password-card .form-stack label {
    grid-template-columns: 82px minmax(0, 1fr);
}

.membership-plan-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px;
}

.membership-plan-card {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 22px;
    align-items: center;
    padding: 24px;
}

.membership-plan-card h3 {
    margin: 10px 0 6px;
    font-size: 1.35rem;
}

.membership-plan-card p {
    margin: 0;
    color: var(--muted);
}

.membership-plan-meta {
    display: grid;
    justify-items: end;
}

.membership-plan-meta strong {
    color: var(--blue);
    font-size: 1.3rem;
    line-height: 1;
}

.membership-plan-meta > span {
    margin-top: 8px;
    color: var(--muted);
    font-size: 0.82rem;
}

.membership-plan-card .button {
    grid-column: 1 / -1;
}

.locked-content-context {
    margin-top: 18px;
    padding-top: 18px;
    border-top: 1px solid rgba(154, 103, 0, 0.2);
}

.locked-content-context h1 {
    margin: 10px 0 6px;
    font-size: 1.45rem;
}

.article-toc-toggle {
    display: none;
    width: 100%;
    border: 0;
    padding: 0;
    color: var(--ink);
    background: transparent;
    font: inherit;
    font-weight: 900;
    text-align: left;
    cursor: pointer;
}

.footer-inner {
    width: min(var(--site-shell-width), calc(100% - var(--site-shell-gutter)));
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    gap: 20px;
}

.footer-links {
    display: flex;
    gap: 16px;
}

.footer-link-button {
    border: 0;
    padding: 0;
    color: inherit;
    background: transparent;
    font: inherit;
    cursor: pointer;
}

.footer-link-button:hover {
    color: var(--blue);
}

.wechat-dialog {
    width: min(calc(100% - 32px), 380px);
    border: 0;
    border-radius: 18px;
    padding: 0;
    color: var(--ink);
    background: #fff;
    box-shadow: 0 24px 70px rgba(16, 35, 63, 0.28);
}

.wechat-dialog::backdrop {
    background: rgba(16, 35, 63, 0.56);
    backdrop-filter: blur(3px);
}

.wechat-dialog-card {
    position: relative;
    display: grid;
    justify-items: center;
    gap: 10px;
    padding: 30px;
    text-align: center;
}

.wechat-dialog-close-form {
    position: absolute;
    top: 12px;
    right: 12px;
}

.wechat-dialog-close {
    width: 32px;
    height: 32px;
    border: 0;
    border-radius: 50%;
    color: var(--muted);
    background: var(--soft);
    font-size: 1.3rem;
    line-height: 1;
    cursor: pointer;
}

.wechat-dialog-card h2 {
    margin: 4px 0 0;
    font-size: 1.35rem;
}

.wechat-dialog-card p,
.wechat-dialog-card small {
    margin: 0;
    color: var(--muted);
}

.wechat-dialog-card img {
    width: min(100%, 240px);
    height: auto;
    margin: 6px 0;
    border-radius: 10px;
}

.about-page-hero .section-inner {
    max-width: 900px;
}

.about-page-hero h1 {
    max-width: 820px;
}

.about-page-hero p {
    max-width: 760px;
}

.about-story-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
}

.about-story-card,
.about-content-card {
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 28px;
    background: #fff;
}

.about-story-card-accent {
    border-color: rgba(47, 128, 237, 0.28);
    background: linear-gradient(145deg, #f7fbff, #fff);
}

.about-story-card h2 {
    margin: 16px 0 10px;
    font-size: 1.45rem;
}

.about-story-card p,
.about-content-card p {
    margin: 0;
    color: var(--muted);
}

.about-token-card {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    gap: 34px;
    align-items: center;
    margin-top: 18px;
    border: 1px solid rgba(47, 128, 237, 0.24);
    border-radius: 14px;
    padding: 26px 30px;
    background: #10233f;
    color: #fff;
}

.about-token-metric {
    display: grid;
    min-width: 140px;
    padding-right: 32px;
    border-right: 1px solid rgba(255, 255, 255, 0.2);
}

.about-token-metric strong {
    font-size: clamp(2rem, 5vw, 3.4rem);
    line-height: 1;
}

.about-token-metric span {
    margin-top: 7px;
    color: #8ec5ff;
    font-weight: 900;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

.about-token-card h2 {
    margin: 10px 0 7px;
    font-size: 1.45rem;
}

.about-token-card p {
    margin: 0;
    color: rgba(255, 255, 255, 0.72);
}

.about-content-section {
    background: var(--soft);
}

.about-content-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    margin-top: 24px;
}

.about-content-card > strong {
    color: var(--blue);
    font-size: 0.82rem;
}

.about-content-card h3 {
    margin: 14px 0 8px;
    font-size: 1.3rem;
}

.about-content-card a {
    display: inline-flex;
    margin-top: 18px;
    color: var(--blue);
    font-weight: 900;
}

.about-contact-section {
    background: #10233f;
}

.about-contact-card {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 42px;
    align-items: center;
    color: #fff;
}

.about-contact-copy {
    max-width: 620px;
}

.about-contact-copy h2 {
    margin: 14px 0 10px;
    font-size: clamp(1.8rem, 4vw, 2.8rem);
}

.about-contact-copy p {
    color: rgba(255, 255, 255, 0.78);
}

.about-contact-copy small {
    color: rgba(255, 255, 255, 0.58);
}

.about-contact-card > img {
    width: 240px;
    height: 240px;
    border: 10px solid #fff;
    border-radius: 14px;
}

@media (max-width: 760px) {
    .about-story-grid,
    .about-content-grid,
    .about-contact-card,
    .about-token-card {
        grid-template-columns: 1fr;
    }

    .about-token-metric {
        padding: 0 0 18px;
        border-right: 0;
        border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    }

    .about-contact-card {
        justify-items: center;
        text-align: center;
    }
}

@media (max-width: 920px) {
    .site-nav {
        position: sticky;
    }

    .nav-inner {
        position: relative;
        min-height: 58px;
        flex-wrap: nowrap;
        padding: 8px 0;
        gap: 10px;
    }

    .nav-menu-button {
        display: block;
        flex: 0 0 auto;
        margin-left: auto;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        order: initial;
        width: 100%;
        max-height: calc(100vh - 74px);
        overflow-y: auto;
        padding: 10px;
        border: 1px solid var(--line);
        border-radius: 0 0 8px 8px;
        background: #fff;
        box-shadow: 0 18px 38px rgba(32, 73, 128, 0.14);
    }

    .site-nav.is-open .nav-links {
        display: grid;
    }

    .nav-links a {
        padding: 10px 12px;
        border-radius: 6px;
    }

    .nav-links a.active {
        background: #edf5ff;
    }

    .course-catalog-layout,
    .course-reader-layout {
        grid-template-columns: 1fr;
    }

    .course-summary-panel,
    .course-reader-sidebar {
        position: static;
    }

    .course-reader-sidebar nav {
        display: flex;
        max-height: none;
        overflow-x: auto;
        overflow-y: hidden;
        padding-bottom: 4px;
        padding-right: 0;
        scrollbar-gutter: auto;
    }

    .course-reader-sidebar nav a {
        min-width: 210px;
    }
}

@media (max-width: 560px) {
    .site-nav {
        position: sticky;
    }

    .brand {
        font-size: 1.5rem;
    }

    .course-chapter-item {
        grid-template-columns: 42px minmax(0, 1fr);
        gap: 10px;
        padding: 15px;
    }

    .course-chapter-access {
        grid-column: 2;
    }

    .course-reader-section {
        padding: 18px 0 42px;
    }

    .course-reader-content {
        padding: 20px;
    }

    .course-reader-pager,
    .membership-plan-card {
        grid-template-columns: 1fr;
    }

    .course-reader-pager a.next,
    .membership-plan-meta {
        text-align: left;
        justify-items: start;
    }

    .membership-plan-card .button {
        grid-column: auto;
    }

    .footer-inner {
        width: min(100% - 24px, 1180px);
        flex-direction: column;
        align-items: center;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }

    .article-toc > strong {
        display: none;
    }

    .article-toc-toggle {
        display: block;
    }

    .article-toc nav {
        display: none;
        margin-top: 12px;
    }

    .article-toc.is-open nav {
        display: grid;
    }
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--soft);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.65;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
}

img,
svg,
video {
    max-width: 100%;
    height: auto;
}

.site-nav {
    position: sticky;
    top: 0;
    z-index: 10;
    background: rgba(12, 22, 38, 0.94);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(16px);
}

.nav-inner {
    width: min(var(--site-shell-width), calc(100% - var(--site-shell-gutter)));
    min-height: 64px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 24px;
}

.brand {
    color: var(--blue);
    font-weight: 900;
    font-size: 1.5rem;
    margin-right: auto;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 20px;
    color: rgba(255, 255, 255, 0.76);
    font-size: 0.92rem;
    font-weight: 700;
}

.nav-links a:hover,
.nav-links a.active {
    color: #fff;
}

.member-toggle {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 5px;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.08);
}

.member-toggle button {
    border: 0;
    border-radius: 6px;
    padding: 7px 10px;
    color: rgba(255, 255, 255, 0.72);
    background: transparent;
    font-weight: 800;
    cursor: pointer;
}

body.is-guest .member-toggle [data-state="guest"],
body.is-member .member-toggle [data-state="member"] {
    color: #07111f;
    background: var(--green-2);
}

.nav-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 38px;
    padding: 0 14px;
    border-radius: 8px;
    color: #07111f;
    background: var(--green-2);
    font-weight: 900;
}

.hero {
    color: #fff;
    background:
        linear-gradient(135deg, rgba(12, 22, 38, 0.98), rgba(16, 40, 54, 0.94)),
        linear-gradient(90deg, rgba(22, 163, 122, 0.2), rgba(79, 140, 255, 0.12));
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
    background-size: 48px 48px;
    mask-image: linear-gradient(to bottom, #000, transparent 76%);
}

.hero-inner,
.section-inner {
    width: min(var(--site-shell-width), calc(100% - var(--site-shell-gutter)));
    margin: 0 auto;
    position: relative;
}

.hero-inner {
    min-height: 560px;
    padding: 58px 0 50px;
    display: grid;
    grid-template-columns: minmax(0, 1.05fr) minmax(420px, 0.95fr);
    gap: 54px;
    align-items: center;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--green-2);
    font-size: 0.8rem;
    font-weight: 900;
    letter-spacing: 0;
}

.hero h1,
.page-title {
    margin: 16px 0 18px;
    font-size: clamp(2.35rem, 4.7vw, 4.2rem);
    line-height: 1.12;
}

.hero-lead,
.page-lead {
    max-width: 680px;
    margin: 0;
    color: rgba(255, 255, 255, 0.74);
    font-size: 1.08rem;
}

.hero-actions,
.actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 28px;
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 44px;
    padding: 0 16px;
    border-radius: 8px;
    border: 1px solid var(--line);
    background: #fff;
    color: var(--ink);
    font-weight: 900;
    text-align: center;
    white-space: normal;
}

.button.primary {
    border-color: var(--green-2);
    background: var(--green-2);
    color: #07111f;
}

.button.dark {
    border-color: var(--dark);
    background: var(--dark);
    color: #fff;
}

.button.ghost {
    color: #fff;
    border-color: rgba(255, 255, 255, 0.22);
    background: rgba(255, 255, 255, 0.06);
}

.metrics {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
    margin-top: 40px;
}

.metric {
    border-left: 1px solid rgba(255, 255, 255, 0.16);
    padding-left: 16px;
}

.metric strong {
    display: block;
    color: var(--green-2);
    font-size: 1.7rem;
    line-height: 1.1;
}

.metric span {
    color: rgba(255, 255, 255, 0.62);
    font-size: 0.85rem;
}

.product-window {
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: 8px;
    background: rgba(7, 15, 28, 0.74);
    box-shadow: 0 28px 80px rgba(0, 0, 0, 0.34);
}

.window-bar {
    height: 44px;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 0 14px;
    color: rgba(255, 255, 255, 0.64);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(255, 255, 255, 0.07);
    font-size: 0.78rem;
    font-weight: 800;
}

.dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #ff6b6b;
}

.dot:nth-child(2) {
    background: #f7c948;
}

.dot:nth-child(3) {
    background: #5ee6a8;
}

.window-title {
    margin-left: auto;
}

.window-body {
    display: grid;
    grid-template-columns: 160px 1fr;
}

.window-side {
    padding: 14px;
    border-right: 1px solid rgba(255, 255, 255, 0.1);
}

.window-side span {
    display: block;
    margin-bottom: 8px;
    padding: 9px 10px;
    border-radius: 6px;
    color: rgba(255, 255, 255, 0.62);
    font-size: 0.82rem;
    font-weight: 800;
}

.window-side span.active {
    color: #fff;
    background: rgba(94, 230, 168, 0.14);
}

.window-main {
    padding: 24px;
}

.task-line {
    margin-bottom: 12px;
    padding: 13px 14px;
    border-radius: 6px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.06);
    color: rgba(255, 255, 255, 0.82);
    font-size: 0.9rem;
}

.task-line.accent {
    border-color: rgba(94, 230, 168, 0.34);
    background: rgba(94, 230, 168, 0.1);
}

.progress {
    height: 8px;
    border-radius: 999px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.12);
}

.progress span {
    display: block;
    height: 100%;
    width: 78%;
    background: linear-gradient(90deg, var(--green-2), #6eb7ff);
}

.section {
    padding: 72px 0;
}

.section.white {
    background: #fff;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.section-head {
    max-width: 760px;
    margin-bottom: 30px;
}

.section-head.center {
    margin-left: auto;
    margin-right: auto;
    text-align: center;
}

.section h2,
.section-title {
    margin: 8px 0 10px;
    font-size: clamp(1.65rem, 3vw, 2.35rem);
    line-height: 1.22;
}

.section-copy {
    margin: 0;
    color: var(--muted);
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 16px;
}

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
}

.card {
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel);
    box-shadow: 0 14px 34px rgba(25, 36, 52, 0.07);
    padding: 22px;
}

.card.dark {
    background: var(--dark);
    border-color: var(--dark);
    color: #fff;
}

.card h3 {
    margin: 10px 0 8px;
    font-size: 1.35rem;
}

.card p {
    color: var(--muted);
    margin: 0;
}

.card.dark p {
    color: rgba(255, 255, 255, 0.72);
}

.badge {
    display: inline-flex;
    align-items: center;
    min-height: 26px;
    padding: 0 9px;
    border: 1px solid var(--line);
    border-radius: 999px;
    color: var(--muted);
    font-size: 0.74rem;
    font-weight: 900;
}

.badge.member {
    color: #704d00;
    border-color: rgba(216, 155, 33, 0.32);
    background: #fff5d6;
}

.tag-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 20px;
}

.tag {
    border-radius: 6px;
    background: #edf3f8;
    color: #526173;
    padding: 4px 8px;
    font-size: 0.75rem;
    font-weight: 800;
}

.dark .tag {
    color: #c9f8e5;
    background: rgba(94, 230, 168, 0.12);
}

.feature-list {
    display: grid;
    gap: 12px;
    margin: 22px 0 0;
    padding: 0;
    list-style: none;
}

.feature-list li {
    border-top: 1px solid var(--line);
    padding-top: 12px;
    color: var(--muted);
}

.dark .feature-list li {
    border-color: rgba(255, 255, 255, 0.12);
    color: rgba(255, 255, 255, 0.72);
}

.member-strip {
    border: 1px solid rgba(216, 155, 33, 0.28);
    border-radius: 8px;
    padding: 18px;
    background: #fff8e5;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 18px;
    align-items: center;
}

.member-strip strong {
    color: #704d00;
}

.member-strip p {
    margin: 4px 0 0;
    color: #775d24;
}

.member-only {
    display: none !important;
}

body.is-member .member-only {
    display: block !important;
}

body.is-member .member-only.inline {
    display: inline-flex !important;
}

body.is-member .member-only.roadmap-item {
    display: grid !important;
}

body.is-member .guest-only {
    display: none;
}

.locked {
    position: relative;
    overflow: hidden;
}

.locked::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.92));
}

body.is-member .locked::after {
    display: none;
}

.page-hero {
    color: #fff;
    background: var(--dark);
    padding: 42px 0 34px;
}

.page-hero .section-inner {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 30px;
    align-items: end;
}

.crumb {
    color: rgba(255, 255, 255, 0.62);
    font-weight: 800;
    font-size: 0.86rem;
}

.product-hero {
    color: #fff;
    background:
        linear-gradient(135deg, rgba(12, 22, 38, 0.98), rgba(14, 36, 42, 0.96)),
        linear-gradient(90deg, rgba(94, 230, 168, 0.18), rgba(79, 140, 255, 0.1));
    overflow: hidden;
}

.products-hero {
    color: var(--ink);
    background:
        radial-gradient(circle at 84% 16%, rgba(56, 189, 248, 0.22), transparent 34%),
        linear-gradient(135deg, #f8fcff 0%, #eaf4ff 48%, #dfefff 100%);
    overflow: hidden;
}

.learning-hero {
    color: var(--ink);
    background:
        radial-gradient(circle at 78% 18%, rgba(47, 128, 237, 0.18), transparent 34%),
        linear-gradient(135deg, #f8fcff 0%, #edf7ff 54%, #e5f1ff 100%);
    overflow: hidden;
}

.products-hero .section-inner {
    min-height: 360px;
    padding: 42px 0 38px;
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(360px, 0.72fr);
    gap: 56px;
    align-items: center;
}

.learning-hero .section-inner {
    min-height: 340px;
    padding: 40px 0 36px;
    display: grid;
    gap: 40px;
    align-content: center;
}

.products-hero .page-title,
.learning-hero .page-title,
.product-hero .page-title {
    margin: 12px 0 14px;
    font-size: clamp(1.7rem, 2.65vw, 2.25rem);
    line-height: 1.14;
}

.products-hero .page-lead,
.learning-hero .page-lead {
    color: var(--muted);
    font-size: 0.96rem;
    line-height: 1.75;
}

.learning-hero-copy {
    max-width: 820px;
    text-align: center;
    margin: 0 auto;
}

.learning-hero-copy .page-lead {
    margin-left: auto;
    margin-right: auto;
}

.learning-hero-copy .hero-actions {
    justify-content: center;
}

.tutorial-shelf {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 12px;
    padding: 14px;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.78);
    box-shadow: 0 26px 70px rgba(47, 128, 237, 0.16);
}

.shelf-tab {
    min-height: 82px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    color: var(--blue);
    background: rgba(239, 246, 255, 0.84);
    font-weight: 900;
    text-align: center;
}

.shelf-tab.active {
    color: #fff;
    background: var(--blue);
    border-color: var(--blue);
}

.shelf-tab.member {
    color: #b7791f;
    background: #fff5d6;
    border-color: rgba(216, 155, 33, 0.32);
}

.shelf-search {
    grid-column: 1 / -1;
    min-height: 160px;
    padding: 22px;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    background:
        linear-gradient(135deg, rgba(47, 128, 237, 0.1), rgba(56, 189, 248, 0.06)),
        #fff;
}

.shelf-search span {
    color: var(--blue);
    font-size: 0.8rem;
    font-weight: 900;
}

.shelf-search strong {
    display: block;
    margin-top: 26px;
    color: var(--ink);
    font-size: 1.45rem;
    line-height: 1.2;
}

.shelf-search p {
    max-width: 620px;
    margin: 12px 0 0;
    color: var(--muted);
}

.tutorial-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
}

@media (max-width: 1024px) {
    .tutorial-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (max-width: 768px) {
    .tutorial-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

.tutorial-card {
    min-height: auto;
    display: flex;
    flex-direction: column;
    padding: 16px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 2px 8px rgba(47, 95, 150, 0.04);
}

.tutorial-card-top,
.tutorial-card-meta,
.tutorial-card-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    align-items: center;
    justify-content: space-between;
}

.tutorial-card-top strong {
    color: var(--blue);
    font-size: 1.2rem;
    line-height: 1;
}

.tutorial-card h3 {
    margin: 12px 0 0;
    padding-bottom: 6px;
    font-size: 0.98rem;
    font-weight: 800;
    line-height: 1.4;
    border-bottom: 1px solid var(--line);
}
.tutorial-card p {
    margin: 8px 0 0;
    text-indent: 16px;
    color: var(--muted);
    font-size: 0.82rem;
    line-height: 1.5;
}

.tutorial-card-meta {
    justify-content: flex-start;
    margin-top: auto;
    padding-top: 10px;
    color: var(--muted);
    font-size: 0.76rem;
    font-weight: 800;
}

.tutorial-card-meta span {
    padding: 3px 6px;
    border-radius: 4px;
    background: #eaf4ff;
}

.tutorial-card-actions {
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid var(--line);
}

.tutorial-card-actions a {
    color: var(--blue);
    font-weight: 900;
}

.learning-method-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.learning-method-grid article {
    min-height: 230px;
    display: flex;
    flex-direction: column;
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 14px 34px rgba(47, 95, 150, 0.08);
}

.learning-method-grid span {
    color: var(--blue);
    font-size: 0.82rem;
    font-weight: 900;
}

.learning-method-grid h3 {
    margin: 28px 0 10px;
    font-size: 1.25rem;
}

.learning-method-grid p {
    margin: 0;
    color: var(--muted);
}

.learning-method-grid a {
    margin-top: auto;
    padding-top: 18px;
    color: var(--blue);
    font-weight: 900;
}

.product-map-panel {
    overflow: hidden;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.78);
    box-shadow: 0 26px 70px rgba(47, 128, 237, 0.16);
}

.map-panel-top {
    min-height: 44px;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 0 14px;
    color: #687b94;
    border-bottom: 1px solid rgba(47, 128, 237, 0.14);
    background: rgba(239, 246, 255, 0.86);
}

.map-panel-top span {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #ff6b6b;
}

.map-panel-top span:nth-child(2) {
    background: #f7c948;
}

.map-panel-top span:nth-child(3) {
    background: var(--green-2);
}

.map-panel-top strong {
    margin-left: auto;
    font-size: 0.78rem;
}

.map-panel-body {
    padding: 28px;
    display: grid;
    grid-template-columns: 1fr 36px 1fr 36px 1fr;
    gap: 14px;
    align-items: center;
}

.map-node {
    min-height: 92px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 14px;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    color: #38516f;
    background: rgba(239, 246, 255, 0.84);
    font-weight: 900;
    text-align: center;
}

.map-node.active {
    color: #fff;
    background: var(--blue);
    border-color: var(--blue);
}

.map-node.member {
    color: #704d00;
    background: #fff5d6;
    border-color: rgba(216, 155, 33, 0.32);
}

.map-link {
    height: 2px;
    background: linear-gradient(90deg, rgba(47, 128, 237, 0.2), var(--blue));
}

.products-overview {
    background: var(--soft);
}

.product-feature-block {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 24px;
    align-items: end;
    margin-bottom: 24px;
    padding: 30px;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    background:
        linear-gradient(135deg, rgba(47, 128, 237, 0.12), rgba(56, 189, 248, 0.06)),
        #fff;
    box-shadow: 0 18px 42px rgba(47, 95, 150, 0.09);
}

.product-feature-block h2 {
    margin: 16px 0 10px;
    font-size: clamp(1.8rem, 3vw, 2.5rem);
    line-height: 1.15;
}

.product-feature-block p {
    max-width: 680px;
    margin: 0;
    color: var(--muted);
}

.feature-meta {
    display: grid;
    gap: 14px;
    justify-items: end;
}

.feature-meta span {
    border-radius: 6px;
    color: #4b6583;
    background: #eaf4ff;
    padding: 6px 10px;
    font-size: 0.8rem;
    font-weight: 900;
}

.product-system-grid {
    display: grid;
    gap: 14px;
}

.product-system-card {
    display: grid;
    grid-template-columns: 92px minmax(0, 1fr);
    gap: 22px;
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 14px 34px rgba(47, 95, 150, 0.08);
}

.system-card-index {
    color: var(--blue);
    font-size: 2.4rem;
    line-height: 1;
    font-weight: 900;
}

.system-card-main h3 {
    margin: 12px 0 8px;
    font-size: 1.35rem;
}

.system-card-main p {
    margin: 0;
    color: var(--muted);
}

.system-card-foot {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
    justify-content: space-between;
    margin-top: 18px;
    padding-top: 16px;
    border-top: 1px solid var(--line);
}

.system-card-foot span {
    color: #4b6583;
    font-size: 0.82rem;
    font-weight: 900;
}

.system-card-foot a {
    color: var(--blue);
    font-weight: 900;
}

.product-layer-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.product-layer-grid article {
    min-height: 220px;
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 14px 34px rgba(47, 95, 150, 0.08);
}

.product-layer-grid span {
    color: var(--blue);
    font-size: 1.8rem;
    line-height: 1;
    font-weight: 900;
}

.product-layer-grid h3 {
    margin: 34px 0 10px;
    font-size: 1.25rem;
}

.product-layer-grid p {
    margin: 0;
    color: var(--muted);
}

.product-hero .section-inner {
    min-height: 380px;
    padding: 42px 0 38px;
    display: grid;
    grid-template-columns: minmax(0, 0.92fr) minmax(360px, 0.78fr);
    gap: 56px;
    align-items: center;
}

.product-hero-copy {
    min-width: 0;
}

.product-subtitle {
    margin: -2px 0 14px;
    color: var(--green-2);
    font-size: 0.98rem;
    font-weight: 900;
}

.product-hero .page-lead {
    font-size: 0.96rem;
    line-height: 1.75;
}

.product-showcase {
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 8px;
    background: rgba(7, 15, 28, 0.76);
    box-shadow: 0 28px 80px rgba(0, 0, 0, 0.34);
}

.showcase-top {
    min-height: 44px;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 0 14px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(255, 255, 255, 0.07);
}

.showcase-top span {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: #ff6b6b;
}

.showcase-top span:nth-child(2) {
    background: #f7c948;
}

.showcase-top span:nth-child(3) {
    background: var(--green-2);
}

.showcase-top strong {
    margin-left: auto;
    color: rgba(255, 255, 255, 0.68);
    font-size: 0.78rem;
}

.showcase-body {
    display: grid;
    grid-template-columns: 116px minmax(0, 1fr);
}

.showcase-rail {
    padding: 16px 12px;
    border-right: 1px solid rgba(255, 255, 255, 0.1);
}

.showcase-rail span {
    display: block;
    margin-bottom: 8px;
    padding: 8px 9px;
    border-radius: 6px;
    color: rgba(255, 255, 255, 0.58);
    font-size: 0.8rem;
    font-weight: 900;
}

.showcase-rail .active {
    color: #fff;
    background: rgba(94, 230, 168, 0.14);
}

.showcase-main {
    padding: 24px;
}

.showcase-line {
    width: 72%;
    height: 10px;
    margin-bottom: 12px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.14);
}

.showcase-line.wide {
    width: 92%;
}

.showcase-panel {
    margin-top: 22px;
    padding: 18px;
    border: 1px solid rgba(94, 230, 168, 0.28);
    border-radius: 8px;
    background: rgba(94, 230, 168, 0.1);
}

.showcase-panel strong {
    display: block;
    margin-bottom: 6px;
}

.showcase-panel p {
    margin: 0;
    color: rgba(255, 255, 255, 0.7);
}

.showcase-stack {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
    margin-top: 18px;
}

.showcase-stack span {
    min-height: 42px;
    display: flex;
    align-items: center;
    padding: 0 12px;
    border-radius: 6px;
    color: rgba(255, 255, 255, 0.76);
    background: rgba(255, 255, 255, 0.07);
    font-size: 0.84rem;
    font-weight: 900;
}

.product-brief {
    background: #f7fafc;
}

.brief-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 34px;
}

.brief-grid article {
    padding-top: 20px;
    border-top: 2px solid var(--dark);
}

.brief-grid h2 {
    margin: 14px 0 8px;
    font-size: clamp(1.45rem, 2.6vw, 2rem);
}

.brief-grid p {
    margin: 0;
    color: var(--muted);
}

.capability-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.capability-grid article {
    min-height: 210px;
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
}

.capability-grid span {
    color: var(--green);
    font-weight: 900;
}

.capability-grid h3 {
    margin: 28px 0 10px;
    font-size: 1.25rem;
}

.capability-grid p {
    margin: 0;
    color: var(--muted);
}

.product-content-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 24px;
    align-items: start;
}

.product-body {
    min-width: 0;
}

.product-path {
    position: sticky;
    top: 88px;
    padding: 22px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 14px 34px rgba(25, 36, 52, 0.07);
}

.product-path h2 {
    margin: 14px 0 16px;
    font-size: 1.35rem;
}

.path-list {
    display: grid;
    gap: 10px;
}

.path-list a {
    display: grid;
    gap: 4px;
    padding: 13px 0;
    border-top: 1px solid var(--line);
}

.path-list a:first-child {
    border-top: 0;
}

.path-list strong {
    color: var(--ink);
}

.path-list span {
    color: var(--muted);
    font-size: 0.88rem;
}

.product-member-strip .actions {
    margin-top: 0;
}

.split {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 24px;
    align-items: start;
}

.article-body {
    padding: 34px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
}

.article-body h2 {
    margin-top: 34px;
}

.article-body p {
    color: #44536a;
}

.article-lock {
    width: min(840px, calc(100% - 40px));
}

.article-detail-section .section-inner {
    width: min(1120px, calc(100% - 40px));
}

.article-detail-section {
    padding-top: 28px;
    background: var(--soft);
}

.article-reading-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 24px;
    align-items: start;
}

.article-detail-section .article-body {
    min-width: 0;
    padding: 38px;
    border-color: var(--line);
    box-shadow: none;
}

.article-cover {
    margin: 0 0 32px;
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--line);
}

.article-cover img {
    display: block;
    width: 100%;
    height: auto;
}

.course-cover {
    margin: 0 0 32px;
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--line);
}

.course-cover img {
    display: block;
    width: 100%;
    height: auto;
}

.article-item-cover {
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 12px;
    aspect-ratio: 16 / 9;
}

.article-item-cover img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.article-detail-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    align-items: center;
    margin-bottom: 14px;
    color: var(--muted);
    font-size: 0.84rem;
    font-weight: 900;
}

.article-detail-tags {
    margin: 0 0 14px;
}

.article-detail-tags .tag {
    border: 1px solid #b9d5e8;
    background: #edf7ff;
    color: #175f89;
}

.article-detail-title {
    margin: 0;
    color: var(--ink);
    font-size: clamp(1.5rem, 2.4vw, 2.1rem);
    line-height: 1.24;
}

.article-detail-excerpt {
    max-width: 760px;
    margin: 14px 0 30px;
    color: var(--muted);
    font-size: 1.02rem;
    line-height: 1.72;
}

.article-toc {
    position: sticky;
    top: 88px;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
}

.article-toc strong {
    display: block;
    margin-bottom: 12px;
    color: var(--ink);
    font-size: 0.96rem;
}

.article-detail-section .mermaid {
    margin: 28px auto;
    padding: 24px;
    background: #fafafa;
    border: 1px solid var(--line);
    border-radius: 10px;
    text-align: center;
    overflow-x: auto;
}

.article-detail-section .mermaid svg {
    max-width: 100%;
    height: auto;
}

.course-chapter-body .mermaid {
    margin: 28px auto;
    padding: 24px;
    background: #fafafa;
    border: 1px solid var(--line);
    border-radius: 10px;
    text-align: center;
    overflow-x: auto;
}

.course-chapter-body .mermaid svg {
    max-width: 100%;
    height: auto;
}

.article-toc nav {
    display: grid;
    gap: 8px;
    max-height: calc(100vh - 160px);
    overflow-y: auto;
    overscroll-behavior: contain;
    padding-right: 4px;
    scrollbar-gutter: stable;
}

.article-toc a {
    color: var(--muted);
    font-size: 0.88rem;
    line-height: 1.45;
}

.article-toc a:hover {
    color: var(--blue);
}

.article-toc a.is-sub {
    padding-left: 12px;
    font-size: 0.82rem;
}

.article-detail-section .article-body > *:first-child {
    margin-top: 0;
}

.article-detail-section .article-body h1,
.article-detail-section .article-body h2,
.article-detail-section .article-body h3 {
    color: var(--ink);
    line-height: 1.25;
}

.article-detail-section .article-body h2 {
    margin-top: 36px;
    padding-top: 6px;
    font-size: 1.55rem;
}

.article-detail-section .article-body h3 {
    margin-top: 28px;
    font-size: 1.25rem;
}

.article-detail-section .article-body p,
.article-detail-section .article-body li {
    color: #40536f;
    font-size: 1.02rem;
    line-height: 1.88;
}

.article-detail-section .article-body ul,
.article-detail-section .article-body ol {
    padding-left: 1.4em;
}

.article-detail-section .article-body code {
    border-radius: 6px;
    padding: 2px 5px;
    color: #1750a6;
    background: #eaf4ff;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.article-detail-section .article-body pre {
    overflow-x: auto;
    padding: 18px;
    border-radius: 8px;
    color: #eaf4ff;
    background: #10233f;
}

.article-detail-section .article-body pre code {
    padding: 0;
    color: inherit;
    background: transparent;
}

.article-lock {
    padding: 28px;
    border: 1px solid rgba(216, 155, 33, 0.28);
    border-radius: 8px;
    background: #fff8e5;
}

.article-lock h3 {
    margin: 0 0 8px;
    color: #704d00;
}

.article-lock p {
    margin: 0;
    color: #775d24;
}

.sidebar {
    display: grid;
    gap: 16px;
    position: sticky;
    top: 88px;
}

.price {
    display: flex;
    align-items: baseline;
    gap: 6px;
    margin: 14px 0;
}

.price strong {
    font-size: 2rem;
}

.roadmap {
    display: grid;
    gap: 12px;
}

.roadmap-item {
    display: grid;
    grid-template-columns: 64px 1fr;
    gap: 16px;
    border-top: 1px solid var(--line);
    padding-top: 16px;
}

.roadmap-item span {
    color: var(--green);
    font-weight: 900;
}

.content-card {
    min-height: 260px;
    display: flex;
    flex-direction: column;
}

.content-meta {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: auto;
    padding-top: 20px;
}

.content-meta span {
    border-radius: 6px;
    background: #edf3f8;
    color: #526173;
    padding: 4px 8px;
    font-size: 0.75rem;
    font-weight: 800;
}

.home-product-carousel {
    display: grid;
    grid-template-columns: minmax(320px, 0.92fr) minmax(0, 1.08fr);
    gap: 20px;
    align-items: stretch;
}

.featured-product,
.rail-product-card {
    position: relative;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    box-shadow: 0 18px 42px rgba(47, 95, 150, 0.09);
}

.featured-product {
    min-height: 340px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 28px;
    background:
        linear-gradient(135deg, rgba(47, 128, 237, 0.14), rgba(56, 189, 248, 0.08)),
        #fff;
}

.featured-product::after {
    content: "";
    position: absolute;
    right: -54px;
    bottom: -54px;
    width: 220px;
    height: 220px;
    border: 32px solid rgba(47, 128, 237, 0.08);
    border-radius: 50%;
}

.featured-product h3 {
    margin: 28px 0 12px;
    position: relative;
    z-index: 1;
    font-size: clamp(1.65rem, 3vw, 2.25rem);
    line-height: 1.15;
}

.featured-product p {
    max-width: 520px;
    margin: 0;
    position: relative;
    z-index: 1;
    color: var(--muted);
}

.featured-product-foot {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 14px;
    flex-wrap: wrap;
    position: relative;
    z-index: 1;
}

.product-rail-wrap {
    min-width: 0;
    display: grid;
    grid-template-rows: auto 1fr;
    gap: 12px;
}

.rail-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    min-height: 44px;
}

.rail-head strong {
    font-size: 1rem;
}

.rail-controls {
    display: flex;
    gap: 8px;
}

.rail-controls button {
    width: 36px;
    height: 36px;
    border: 1px solid var(--line);
    border-radius: 8px;
    color: var(--blue);
    background: #fff;
    font-size: 1.5rem;
    line-height: 1;
    font-weight: 900;
    cursor: pointer;
}

.product-rail {
    display: grid;
    grid-auto-flow: column;
    grid-auto-columns: minmax(240px, 68%);
    gap: 14px;
    overflow-x: auto;
    overscroll-behavior-inline: contain;
    scroll-snap-type: inline mandatory;
    scroll-padding-inline: 2px;
    padding: 2px 2px 14px;
    scrollbar-width: thin;
    -webkit-overflow-scrolling: touch;
}

.rail-product-card {
    min-height: 284px;
    display: flex;
    flex-direction: column;
    padding: 22px;
    scroll-snap-align: start;
}

.product-index {
    color: var(--blue);
    font-size: 2.4rem;
    line-height: 1;
    font-weight: 900;
}

.rail-product-card h3 {
    margin: 26px 0 10px;
    position: relative;
    z-index: 1;
    font-size: 1.28rem;
}

.rail-product-card p {
    margin: 0;
    position: relative;
    z-index: 1;
    color: var(--muted);
}

.all-products-card {
    color: inherit;
    background:
        linear-gradient(135deg, rgba(23, 59, 117, 0.92), rgba(47, 128, 237, 0.88)),
        var(--dark);
}

.all-products-card .product-index,
.all-products-card h3,
.all-products-card strong {
    color: #fff;
}

.all-products-card p {
    color: rgba(255, 255, 255, 0.72);
}

.product-code {
    width: fit-content;
    max-width: 100%;
    margin-top: auto;
    padding: 6px 10px;
    position: relative;
    z-index: 1;
    border-radius: 6px;
    color: #4b6583;
    background: #eaf4ff;
    font-size: 0.8rem;
    font-weight: 900;
}

.product-link {
    margin-top: 16px;
    position: relative;
    z-index: 1;
    color: var(--blue);
    font-weight: 900;
}

.home-learning-path {
    display: grid;
    gap: 0;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}

.learning-step {
    display: grid;
    grid-template-columns: 92px minmax(0, 1fr);
    gap: 24px;
    padding: 24px 0;
    border-top: 1px solid var(--line);
}

.learning-step:first-child {
    border-top: 0;
}

.step-marker {
    position: relative;
    min-height: 100%;
    color: var(--blue);
    font-size: 2.2rem;
    font-weight: 900;
    line-height: 1;
}

.step-marker::after {
    content: "";
    position: absolute;
    left: 18px;
    top: 46px;
    bottom: -24px;
    width: 1px;
    background: var(--line);
}

.learning-step:last-child .step-marker::after {
    display: none;
}

.step-content {
    min-width: 0;
}

.step-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    color: var(--muted);
    font-size: 0.82rem;
    font-weight: 900;
}

.step-content h3 {
    margin: 10px 0 8px;
    font-size: 1.35rem;
}

.step-content p {
    max-width: 760px;
    margin: 0;
    color: var(--muted);
}

.course-row {
    display: grid;
    grid-template-columns: 120px minmax(0, 1fr) auto;
    gap: 18px;
    align-items: center;
    border-top: 1px solid var(--line);
    padding: 18px 0;
}

.course-row:first-child {
    border-top: 0;
    padding-top: 0;
}

.course-row strong {
    display: block;
}

.course-row p {
    margin: 4px 0 0;
    color: var(--muted);
}

.course-index {
    color: var(--green);
    font-weight: 900;
}

.article-list {
    display: grid;
    gap: 14px;
}

.article-item {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 18px;
    align-items: center;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    padding: 18px;
    box-shadow: 0 10px 28px rgba(25, 36, 52, 0.05);
}

.article-item h3 {
    margin: 8px 0 6px;
    font-size: 1.16rem;
}

.article-item p {
    margin: 0;
    color: var(--muted);
}

.article-date {
    color: var(--muted);
    font-size: 0.82rem;
    font-weight: 800;
}

.article-index-section {
    padding-top: 28px;
}

.search-section,
.membership-section {
    padding-top: 28px;
}

.membership-hero {
    padding: 34px 0 30px;
    color: #122033;
    background:
        linear-gradient(120deg, rgba(255, 255, 255, 0.88), rgba(240, 248, 255, 0.66)),
        linear-gradient(135deg, #f8fbff 0%, #edf6ff 52%, #dff0ff 100%);
    border-bottom: 1px solid #cfe5f8;
    position: relative;
    overflow: hidden;
}

.membership-hero .section-inner {
    max-width: var(--site-shell-width);
}

.membership-hero h1 {
    margin: 10px 0 8px;
    color: #0f2747;
    font-size: clamp(1.75rem, 2.6vw, 2.25rem);
    line-height: 1.16;
}

.membership-hero p {
    margin: 0;
    max-width: 680px;
    color: #52657b;
    font-size: 1rem;
}

.membership-hero .eyebrow {
    color: #1c64f2;
}

.search-section .search-form {
    margin: 0 0 18px;
}

.article-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 16px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--line);
}

.article-toolbar div {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: baseline;
}

.article-toolbar strong {
    color: var(--ink);
    font-size: 1.2rem;
}

.article-toolbar span {
    color: var(--muted);
    font-size: 0.92rem;
}

.article-toolbar a {
    color: var(--blue);
    font-weight: 900;
}

.article-index-section .article-list {
    gap: 10px;
}

.article-index-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 300px;
    gap: 22px;
    align-items: start;
}

.article-index-section .article-item {
    padding: 16px 18px;
    box-shadow: none;
}

.article-index-section .article-item:hover {
    border-color: rgba(47, 128, 237, 0.36);
    background: #f8fbff;
}

.article-index-section .article-item h3 {
    margin: 8px 0 4px;
    font-size: 1.08rem;
}

.article-index-section .article-date {
    align-self: start;
    padding-top: 4px;
}

.article-load-more,
.article-list-end {
    width: 100%;
    padding: 14px;
    color: var(--muted);
    border: 0;
    background: transparent;
    font: inherit;
    text-align: center;
}

.article-load-more {
    cursor: pointer;
}

.article-load-more:hover,
.article-load-more:focus-visible {
    color: var(--blue);
}

.article-load-more[aria-busy="true"] {
    cursor: wait;
}


.article-sidebar {
    display: grid;
    gap: 16px;
    position: sticky;
    top: 88px;
}

.article-sidebar section {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
}

.article-sidebar h2 {
    margin: 0 0 12px;
    font-size: 1rem;
}

.sidebar-link {
    display: grid;
    grid-template-columns: 34px minmax(0, 1fr);
    gap: 10px;
    padding: 12px 0;
    border-top: 1px solid var(--line);
}

.sidebar-link:first-of-type {
    border-top: 0;
    padding-top: 0;
}

.sidebar-link span {
    color: var(--blue);
    font-weight: 900;
}

.sidebar-link strong {
    color: var(--ink);
    font-size: 0.94rem;
    line-height: 1.45;
}

.sidebar-link small {
    grid-column: 2;
    color: var(--muted);
    font-size: 0.78rem;
    font-weight: 800;
}

.sidebar-link.course span {
    color: #b7791f;
}

.filter-bar {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 22px;
}

.filter-chip {
    border: 1px solid var(--line);
    border-radius: 999px;
    background: #fff;
    color: var(--muted);
    padding: 7px 12px;
    font-size: 0.85rem;
    font-weight: 900;
}

.filter-chip.active {
    color: #fff;
    background: var(--dark);
    border-color: var(--dark);
}

.account-row {
    display: grid;
    grid-template-columns: 160px minmax(0, 1fr);
    gap: 16px;
    border-top: 1px solid var(--line);
    padding: 14px 0;
}

.account-row:first-child {
    border-top: 0;
}

.account-row span {
    color: var(--muted);
    font-weight: 800;
}

.account-row strong {
    color: var(--ink);
}

.account-section {
    min-height: calc(100vh - 170px);
    display: flex;
    align-items: center;
    background: var(--soft);
}

.account-card {
    width: min(100%, 620px);
    margin: 0 auto;
    padding: 30px;
}

.account-card h3 {
    margin-bottom: 4px;
    font-size: 1.55rem;
}

.account-intro {
    margin: 0 0 18px;
    color: var(--muted);
}

.status-pill {
    display: inline-flex;
    align-items: center;
    min-height: 28px;
    padding: 0 10px;
    border-radius: 999px;
    color: #704d00;
    background: #fff5d6;
    border: 1px solid rgba(216, 155, 33, 0.32);
    font-size: 0.78rem;
    font-weight: 900;
}

.form-stack {
    display: grid;
    gap: 12px;
    margin-top: 14px;
}

.form-stack label {
    display: grid;
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 10px;
    align-items: center;
    color: var(--muted);
    font-weight: 800;
}

.form-stack label > span {
    white-space: nowrap;
}

.form-stack input {
    width: 100%;
    min-height: 42px;
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 0 12px;
    color: var(--ink);
    background: #fff;
}

.auth-card {
    width: min(100%, 620px);
    margin: 0 auto;
    padding: 26px 28px;
}

.auth-section {
    min-height: calc(100vh - 130px);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px 0;
    background: var(--soft);
}

.account-application-entry {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    margin-top: 18px;
    border-top: 1px solid var(--line);
    padding-top: 15px;
    color: #667085;
    font-size: 0.88rem;
}

.account-application-entry button {
    border: 0;
    border-radius: 6px;
    padding: 4px 6px;
    color: #2563eb;
    background: transparent;
    font: inherit;
    font-weight: 800;
    cursor: pointer;
}

.account-application-entry button::after {
    content: " →";
}

.account-application-entry button:hover,
.account-application-entry button:focus-visible {
    color: #1d4ed8;
    background: #eff6ff;
    outline: none;
}

.account-application-dialog {
    width: min(calc(100% - 32px), 420px);
    border: 0;
    border-radius: 18px;
    padding: 0;
    color: #10233f;
    background: #fff;
    box-shadow: 0 28px 80px rgba(16, 35, 63, 0.3);
}

.account-application-dialog::backdrop {
    background: rgba(16, 35, 63, 0.58);
    backdrop-filter: blur(3px);
}

.account-application-dialog-card {
    position: relative;
    display: grid;
    justify-items: center;
    gap: 9px;
    padding: 30px;
    text-align: center;
}

.account-application-dialog-close-form {
    position: absolute;
    top: 12px;
    right: 12px;
}

.account-application-dialog-close {
    width: 32px;
    height: 32px;
    border: 0;
    border-radius: 50%;
    color: #667085;
    background: #f2f4f7;
    font-size: 1.3rem;
    line-height: 1;
    cursor: pointer;
}

.account-application-eyebrow {
    color: #2563eb;
    font-size: 0.76rem;
    font-weight: 900;
    letter-spacing: 0.12em;
}

.account-application-dialog-card h2 {
    margin: 2px 0 0;
    color: #10233f;
    font-size: 1.4rem;
}

.account-application-intro {
    margin: 0;
    color: #667085;
    font-size: 0.9rem;
}

.account-application-dialog-card > img {
    width: min(100%, 220px);
    height: auto;
    margin: 8px 0 4px;
    border: 1px solid #e4e7ec;
    border-radius: 12px;
}

.account-application-instruction {
    width: 100%;
    border: 1px solid #dbeafe;
    border-radius: 10px;
    padding: 13px 15px;
    background: #eff6ff;
}

.account-application-instruction strong {
    color: #1e3a5f;
    font-size: 0.9rem;
}

.account-application-instruction p {
    margin: 5px 0 0;
    color: #52677f;
    font-size: 0.82rem;
    line-height: 1.6;
}

.account-application-divider {
    position: relative;
    width: 100%;
    margin: 4px 0;
    color: #98a2b3;
    font-size: 0.78rem;
}

.account-application-divider::before {
    content: "";
    position: absolute;
    top: 50%;
    left: 0;
    right: 0;
    border-top: 1px solid #e4e7ec;
}

.account-application-divider span {
    position: relative;
    padding: 0 10px;
    background: #fff;
}

.account-email-toggle {
    width: 100%;
    min-height: 42px;
    border: 1px solid #bfdbfe;
    border-radius: 9px;
    color: #1d4ed8;
    background: #f8fbff;
    font-weight: 800;
    cursor: pointer;
}

.account-email-form {
    position: relative;
    display: grid;
    width: 100%;
    gap: 12px;
    padding-top: 4px;
    text-align: left;
}

.account-email-form[hidden] {
    display: none;
}

.account-email-form label {
    display: grid;
    gap: 6px;
    color: #344054;
    font-size: 0.82rem;
    font-weight: 700;
}

.account-email-form input {
    width: 100%;
    min-height: 42px;
    border: 1px solid #d0d5dd;
    border-radius: 8px;
    padding: 0 11px;
    color: #10233f;
    background: #fff;
}

.account-email-captcha {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 122px auto;
    gap: 7px;
    align-items: center;
}

.account-email-captcha img {
    width: 122px;
    height: 42px;
    border: 1px solid #dbeafe;
    border-radius: 7px;
    object-fit: cover;
}

.account-email-captcha button {
    border: 0;
    padding: 5px;
    color: #2563eb;
    background: transparent;
    font-size: 0.78rem;
    cursor: pointer;
}

.account-email-form small {
    color: #667085;
    font-weight: 400;
    line-height: 1.55;
}

.account-email-message {
    margin: 0;
    border-radius: 8px;
    padding: 9px 11px;
    font-size: 0.82rem;
    line-height: 1.5;
}

.account-email-message.success {
    color: #166534;
    background: #f0fdf4;
}

.account-email-message.error {
    color: #b42318;
    background: #fef3f2;
}

.account-application-honeypot {
    position: absolute !important;
    left: -10000px !important;
    width: 1px !important;
    height: 1px !important;
    overflow: hidden !important;
}

.account-result-card {
    width: min(100%, 560px);
    margin: 0 auto;
    padding: 36px;
    text-align: center;
}

.account-result-card h1 {
    margin: 14px 0 10px;
    font-size: 1.65rem;
}

.account-result-card p {
    margin: 0 0 24px;
    color: #667085;
    line-height: 1.7;
}

.account-result-card .button {
    display: inline-flex;
}

.activation-card .auth-hint strong {
    color: #10233f;
}

.auth-card h3 {
    margin: 10px 0 0;
    font-size: 1.45rem;
}

.auth-hint {
    margin: 0 0 14px;
    color: var(--muted);
    font-size: 0.96rem;
}

.auth-card .actions,
.auth-card .button {
    width: 100%;
}

.auth-card .form-stack {
    gap: 12px;
}

.auth-card .form-stack input {
    min-height: 44px;
    font-size: 0.96rem;
}

.auth-card .button {
    min-height: 44px;
}

.check-row {
    display: inline-flex !important;
    grid-template-columns: none !important;
    align-items: center;
    justify-content: flex-start;
    gap: 8px;
}

.check-row input {
    width: auto;
    min-height: auto;
}

.captcha-row {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 180px auto;
    gap: 8px;
    align-items: center;
}

.captcha-row img {
    width: 180px;
    height: 46px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #eef6ff;
}

.captcha-refresh {
    min-height: 42px;
    border: 1px solid rgba(47, 128, 237, 0.28);
    border-radius: 8px;
    padding: 0 12px;
    color: var(--blue);
    background: #fff;
    font-weight: 900;
    cursor: pointer;
}

.captcha-refresh:hover {
    background: #f8fbff;
}

.search-form {
    width: min(100%, 620px);
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 12px;
    margin-top: 28px;
}

.search-form input {
    width: 100%;
    min-height: 44px;
    border: 1px solid rgba(255, 255, 255, 0.24);
    border-radius: 8px;
    padding: 0 14px;
    color: #fff;
    background: rgba(255, 255, 255, 0.08);
    font: inherit;
    font-weight: 800;
}

.search-form input::placeholder {
    color: rgba(255, 255, 255, 0.58);
}

.footer {
    padding: 34px 0;
    color: var(--muted);
    background: #fff;
    border-top: 1px solid var(--line);
    text-align: center;
}

@media (max-width: 920px) {
    .nav-inner {
        flex-wrap: wrap;
        padding: 12px 0;
        gap: 12px;
    }

    .brand {
        width: auto;
    }

    .nav-links {
        order: 3;
        width: 100%;
        overflow-x: auto;
        gap: 14px;
        padding-bottom: 4px;
        -webkit-overflow-scrolling: touch;
    }

    .nav-links a {
        flex: 0 0 auto;
    }

    .hero-inner,
    .grid-3,
    .grid-4,
    .grid-2,
    .home-product-carousel,
    .page-hero .section-inner,
    .products-hero .section-inner,
    .product-hero .section-inner,
    .brief-grid,
    .capability-grid,
    .product-content-layout,
    .product-feature-block,
    .product-layer-grid,
    .learning-method-grid,
    .tutorial-grid,
    .split {
        grid-template-columns: 1fr;
    }

    .hero-inner {
        min-height: auto;
        padding: 34px 0 36px;
    }

    .product-hero .section-inner {
        min-height: auto;
        padding: 30px 0 32px;
        gap: 18px;
    }

    .products-hero .section-inner {
        min-height: auto;
        padding: 30px 0 32px;
        gap: 18px;
    }

    .learning-hero .section-inner {
        min-height: auto;
        padding: 30px 0 32px;
        gap: 18px;
    }

    .hero .product-window,
    .product-map-panel,
    .product-showcase,
    .tutorial-shelf {
        display: none;
    }

    .tutorial-shelf {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .map-panel-body {
        grid-template-columns: 1fr;
    }

    .map-link {
        width: 2px;
        height: 28px;
        margin: 0 auto;
        background: linear-gradient(180deg, rgba(47, 128, 237, 0.2), var(--blue));
    }

    .feature-meta {
        justify-items: start;
    }

    .product-showcase {
        max-width: 100%;
    }

    .product-path {
        position: static;
    }

    .product-window {
        max-width: 100%;
    }

    .featured-product {
        min-height: 300px;
    }

    .product-rail {
        grid-auto-columns: minmax(230px, 48%);
    }

    .window-body {
        grid-template-columns: 1fr;
    }

    .window-side {
        border-right: 0;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .metrics {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }

    .member-strip {
        grid-template-columns: 1fr;
    }

    .member-strip .button {
        width: 100%;
    }

    .product-member-strip .actions {
        display: grid;
        grid-template-columns: 1fr;
        width: 100%;
    }

    .course-row {
        grid-template-columns: 1fr;
    }

    .learning-step {
        grid-template-columns: 64px minmax(0, 1fr);
        gap: 16px;
    }

    .product-system-card {
        grid-template-columns: 64px minmax(0, 1fr);
        gap: 16px;
    }

    .membership-hero {
        padding: 30px 0 26px;
    }

    .article-index-layout {
        grid-template-columns: 1fr;
    }

    .article-reading-layout {
        grid-template-columns: 1fr;
    }

    .article-toc {
        position: static;
        order: -1;
    }

    .article-toc nav {
        max-height: none;
        overflow-y: visible;
        padding-right: 0;
        scrollbar-gutter: auto;
    }

    .article-sidebar {
        position: static;
    }

    .article-toolbar {
        align-items: flex-start;
    }

    .article-item {
        grid-template-columns: 1fr;
        align-items: start;
    }

    .account-row {
        grid-template-columns: 1fr;
    }

    .sidebar {
        position: static;
    }
}

@media (max-width: 560px) {
    .account-application-dialog {
        width: calc(100% - 16px);
        max-width: none;
        margin: auto auto 8px;
        border-radius: 20px 20px 14px 14px;
    }

    .account-application-dialog-card {
        padding: 28px 22px 22px;
    }

    .account-email-captcha {
        grid-template-columns: minmax(0, 1fr) 112px;
    }

    .account-email-captcha button {
        grid-column: 1 / -1;
        justify-self: end;
    }

    .hero-inner,
    .section-inner,
    .nav-inner {
        width: min(100% - 24px, 1180px);
    }

    .site-nav {
        position: relative;
    }

    .hero h1,
    .page-title {
        font-size: 2rem;
    }

    .products-hero .page-title,
    .learning-hero .page-title,
    .product-hero .page-title {
        margin: 10px 0 12px;
        font-size: 1.58rem;
    }

    .hero-lead,
    .page-lead {
        font-size: 1rem;
    }

    .section {
        padding: 44px 0;
    }

    .card,
    .article-body {
        padding: 18px;
    }

    .article-detail-section .section-inner {
        width: min(100% - 24px, 1120px);
    }

    .article-detail-title {
        font-size: 1.38rem;
    }

    .article-detail-excerpt {
        font-size: 0.96rem;
    }

    .article-detail-section .article-body,
    .article-toc,
    .article-lock {
        padding: 18px;
    }

    .hero-inner {
        padding: 42px 0 44px;
        gap: 28px;
    }

    .page-hero {
        padding: 30px 0 26px;
    }

    .hero-actions,
    .actions,
    .search-form {
        display: grid;
        grid-template-columns: 1fr;
        width: 100%;
    }

    .button,
    .nav-cta {
        width: 100%;
    }

    .member-toggle {
        margin-left: auto;
    }

    .metrics {
        gap: 8px;
        margin-top: 22px;
    }

    .metric {
        padding-left: 10px;
    }

    .metric strong {
        font-size: 1.22rem;
    }

    .metric span {
        font-size: 0.76rem;
    }

    .window-main {
        padding: 16px;
    }

    .featured-product,
    .rail-product-card {
        padding: 20px;
    }

    .product-feature-block {
        padding: 22px;
    }

    .product-system-card {
        padding: 18px;
    }

    .product-index,
    .system-card-index,
    .step-marker {
        font-size: 1.8rem;
    }

    .product-layer-grid article {
        min-height: auto;
    }

    .product-layer-grid h3 {
        margin-top: 18px;
    }

    .tutorial-shelf,
    .tutorial-card,
    .learning-method-grid article {
        padding: 18px;
    }

    .learning-method-grid article {
        min-height: auto;
    }

    .learning-method-grid h3 {
        margin-top: 18px;
    }

    .learning-step {
        padding: 20px 0;
    }

    .tutorial-card {
        min-height: auto;
    }

    .tutorial-card h3 {
        margin-top: 22px;
    }

    .product-rail {
        grid-auto-columns: minmax(230px, 82%);
    }

    .rail-controls button {
        width: 34px;
        height: 34px;
    }

    .step-marker::after {
        left: 14px;
        top: 40px;
        bottom: -20px;
    }

    .showcase-body {
        grid-template-columns: 1fr;
    }

    .showcase-rail {
        display: grid;
        grid-template-columns: repeat(4, minmax(0, 1fr));
        gap: 8px;
        border-right: 0;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .showcase-rail span {
        margin-bottom: 0;
        text-align: center;
    }

    .showcase-main {
        padding: 16px;
    }

    .showcase-stack {
        grid-template-columns: 1fr;
    }

    .capability-grid article {
        min-height: auto;
    }

    .capability-grid h3 {
        margin-top: 16px;
    }

    .window-side {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 8px;
    }

    .window-side span {
        margin-bottom: 0;
    }

    .article-item,
    .member-strip,
    .card {
        box-shadow: 0 8px 22px rgba(25, 36, 52, 0.06);
    }
}

.section .course-summary-panel h2 {
    font-size: 1.25rem;
}

@media (max-width: 380px) {
    .hero h1,
    .page-title {
        font-size: 1.72rem;
    }

    .nav-links {
        font-size: 0.86rem;
    }

    .card h3 {
        font-size: 1.16rem;
    }
}

/* Bright blue theme */
body {
    background:
        linear-gradient(180deg, #f7fbff 0, #f3f8ff 360px),
        var(--soft);
}

.site-nav {
    background: rgba(255, 255, 255, 0.9);
    border-bottom: 1px solid rgba(47, 128, 237, 0.14);
    box-shadow: 0 10px 30px rgba(32, 73, 128, 0.08);
}

.brand {
    color: var(--blue);
}

.nav-links {
    color: #667991;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--blue);
}

.member-toggle {
    border-color: rgba(47, 128, 237, 0.16);
    background: #eef6ff;
}

.member-toggle button {
    color: #5b6f89;
}

body.is-guest .member-toggle [data-state="guest"],
body.is-member .member-toggle [data-state="member"],
.nav-cta,
.button.primary {
    color: #fff;
    border-color: var(--blue);
    background: var(--blue);
}

.hero,
.page-hero,
.product-hero {
    color: var(--ink);
    background:
        radial-gradient(circle at 82% 14%, rgba(56, 189, 248, 0.22), transparent 34%),
        linear-gradient(135deg, #f8fcff 0%, #eaf4ff 50%, #dfefff 100%);
}

.hero::before {
    background-image:
        linear-gradient(rgba(47, 128, 237, 0.08) 1px, transparent 1px),
        linear-gradient(90deg, rgba(47, 128, 237, 0.08) 1px, transparent 1px);
    mask-image: linear-gradient(to bottom, #000, transparent 70%);
}

.eyebrow,
.product-subtitle,
.metric strong,
.course-index,
.roadmap-item span,
.capability-grid span {
    color: var(--blue);
}

.hero-lead,
.page-lead,
.showcase-panel p {
    color: var(--muted);
}

.button {
    border-color: #c8d9ee;
    background: #fff;
    color: var(--ink);
}

.button.dark {
    border-color: var(--blue);
    background: var(--blue);
    color: #fff;
}

.button.ghost {
    color: var(--blue);
    border-color: rgba(47, 128, 237, 0.28);
    background: rgba(255, 255, 255, 0.64);
}

.metrics .metric {
    border-left-color: rgba(47, 128, 237, 0.18);
}

.metric span {
    color: #6d7f96;
}

.product-window,
.product-showcase {
    border-color: rgba(47, 128, 237, 0.18);
    background: rgba(255, 255, 255, 0.78);
    box-shadow: 0 26px 70px rgba(47, 128, 237, 0.16);
}

.window-bar,
.showcase-top {
    color: #687b94;
    border-bottom-color: rgba(47, 128, 237, 0.14);
    background: rgba(239, 246, 255, 0.86);
}

.window-title,
.showcase-top strong {
    color: #52667f;
}

.window-side,
.showcase-rail {
    border-right-color: rgba(47, 128, 237, 0.12);
}

.window-side span,
.showcase-rail span {
    color: #63748c;
}

.window-side span.active,
.showcase-rail .active {
    color: var(--blue);
    background: rgba(47, 128, 237, 0.12);
}

.task-line,
.showcase-stack span {
    color: #38516f;
    border-color: rgba(47, 128, 237, 0.14);
    background: rgba(239, 246, 255, 0.82);
}

.task-line.accent,
.showcase-panel {
    border-color: rgba(47, 128, 237, 0.24);
    background: rgba(219, 234, 254, 0.72);
}

.progress {
    background: rgba(47, 128, 237, 0.14);
}

.progress span {
    background: linear-gradient(90deg, var(--blue), var(--green-2));
}

.card,
.article-item,
.article-body,
.product-path,
.capability-grid article {
    border-color: var(--line);
    box-shadow: 0 14px 34px rgba(47, 95, 150, 0.08);
}

.card.dark {
    background: #173b75;
    border-color: #173b75;
}

.dark .tag {
    color: #d7ecff;
    background: rgba(255, 255, 255, 0.12);
}

.tag,
.content-meta span,
.filter-chip {
    color: #4b6583;
    background: #eaf4ff;
}

.filter-chip.active {
    color: #fff;
    background: var(--blue);
    border-color: var(--blue);
}

.product-brief {
    background: #eef6ff;
}

.brief-grid article {
    border-top-color: var(--blue);
}

.search-form input {
    color: var(--ink);
    border-color: rgba(47, 128, 237, 0.22);
    background: rgba(255, 255, 255, 0.78);
}

.search-form input::placeholder {
    color: #8292a8;
}

.footer,
.section.white {
    background: #fff;
}

@media (max-width: 560px) {
    .showcase-rail {
        border-bottom-color: rgba(47, 128, 237, 0.12);
    }

    .window-side {
        border-bottom-color: rgba(47, 128, 237, 0.12);
    }
}

/* UX refinements from the Open Design pass */
.member-asset-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 12px;
}

.member-asset-grid span,
.product-hero-highlights span {
    display: inline-flex;
    align-items: center;
    min-height: 28px;
    padding: 5px 9px;
    border: 1px solid rgba(47, 128, 237, 0.16);
    border-radius: 6px;
    color: #35516f;
    background: rgba(255, 255, 255, 0.66);
    font-size: 0.78rem;
    font-weight: 900;
}

.product-hero-highlights {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 16px 0 0;
}

.membership-hero .hero-actions {
    margin-top: 22px;
}

.membership-status-strip {
    margin-top: 18px;
    padding: 16px 18px;
    border: 1px solid rgba(47, 128, 237, 0.18);
    border-radius: 8px;
    background: #f8fbff;
}

.membership-status-strip strong {
    color: var(--ink);
}

.membership-status-strip p {
    margin: 6px 0 0;
    color: var(--muted);
}

.card-link,
.read-more,
.system-card-foot strong {
    color: var(--blue);
    font-weight: 900;
}

.card-link {
    display: inline-flex;
    align-items: center;
    margin-top: auto;
    padding-top: 18px;
}

.card-link::after,
.read-more::after,
.system-card-foot strong::after {
    content: " ->";
}

.card:has(.card-link) {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.map-node,
.product-system-card,
.article-item,
.sidebar-link,
.showcase-rail a {
    transition:
        border-color 0.18s ease,
        box-shadow 0.18s ease,
        transform 0.18s ease,
        background 0.18s ease,
        color 0.18s ease;
}

.map-node:hover,
.map-node:focus-visible {
    transform: translateY(-2px);
    box-shadow: 0 12px 28px rgba(47, 128, 237, 0.16);
}

.product-system-card {
    color: inherit;
    text-decoration: none;
}

.product-system-card:hover,
.article-item:hover,
.sidebar-link:hover {
    border-color: rgba(47, 128, 237, 0.36);
    background: #f8fbff;
    box-shadow: 0 18px 42px rgba(47, 95, 150, 0.12);
    transform: translateY(-2px);
}

.product-system-card-more {
    border-color: rgba(216, 155, 33, 0.32);
    background: #fffaf0;
}

.product-system-card-more .system-card-index {
    color: #b7791f;
    font-size: 2rem;
}

.product-system-card-more:hover {
    border-color: rgba(216, 155, 33, 0.52);
    background: #fff7df;
}

.showcase-rail a {
    display: block;
    margin-bottom: 8px;
    padding: 8px 9px;
    border-radius: 6px;
    color: #63748c;
    font-size: 0.8rem;
    font-weight: 900;
}

.showcase-rail a:hover,
.showcase-rail a:focus-visible,
.showcase-rail .active {
    color: var(--blue);
    background: rgba(47, 128, 237, 0.12);
}

.article-item {
    color: inherit;
    text-decoration: none;
}

.read-more {
    justify-self: end;
    align-self: end;
    white-space: nowrap;
}

.sidebar-link {
    border-radius: 8px;
}

.sidebar-link:hover {
    padding-left: 10px;
    padding-right: 10px;
}

@media (max-width: 920px) {
    .read-more {
        justify-self: start;
    }
}

@media (max-width: 560px) {
    .nav-inner {
        min-height: 0;
        padding: 10px 0;
    }

    .brand {
        font-size: 1.5rem;
        line-height: 1.1;
    }

    .nav-inner .nav-cta {
        width: auto;
        min-height: 32px;
        padding: 0 10px;
        border-radius: 6px;
        font-size: 0.82rem;
    }

    .nav-links {
        gap: 10px;
        padding-bottom: 2px;
        font-size: 0.86rem;
    }

    .nav-links a {
        padding: 4px 0;
    }

    .captcha-row {
        grid-template-columns: 1fr 1fr;
    }

    .captcha-row input {
        grid-column: 1 / -1;
    }

    .captcha-row img {
        width: 100%;
        object-fit: contain;
    }

    .form-stack label {
        grid-template-columns: 58px minmax(0, 1fr);
        gap: 8px;
    }

    .member-asset-grid,
    .product-hero-highlights {
        display: grid;
        grid-template-columns: 1fr;
    }

    .membership-hero .hero-actions {
        margin-top: 18px;
    }

    .showcase-rail a {
        margin-bottom: 0;
        text-align: center;
    }
}

/* Final mobile navigation overrides */
@media (max-width: 920px) {
    .site-nav {
        position: sticky;
    }

    .nav-inner {
        position: relative;
        min-height: 58px;
        flex-wrap: nowrap;
        padding: 8px 0;
        gap: 10px;
    }

    .nav-menu-button {
        display: block;
        flex: 0 0 auto;
        margin-left: auto;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        order: initial;
        width: 100%;
        max-height: calc(100vh - 74px);
        overflow-y: auto;
        padding: 10px;
        border: 1px solid var(--line);
        border-radius: 0 0 8px 8px;
        background: #fff;
        box-shadow: 0 18px 38px rgba(32, 73, 128, 0.14);
    }

    .site-nav.is-open .nav-links {
        display: grid;
    }

    .nav-links a {
        padding: 10px 12px;
        border-radius: 6px;
    }

    .nav-links a.active {
        background: #edf5ff;
    }

    .nav-account {
        display: none;
    }

    .nav-links .mobile-account-panel {
        display: grid;
        gap: 6px;
        margin-top: 4px;
        padding: 10px;
        border-top: 1px solid var(--line);
    }

    .nav-links .mobile-account-summary {
        display: flex;
        align-items: center;
        gap: 10px;
        padding: 8px;
        background: #f5f9ff;
    }

    .mobile-account-actions {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 4px;
    }

    .mobile-account-actions .logout-form {
        grid-column: 1 / -1;
    }

    .mobile-account-logout {
        width: 100%;
        padding: 10px 12px;
        border: 0;
        border-radius: 6px;
        color: var(--danger);
        background: transparent;
        font: inherit;
        font-size: 0.86rem;
        font-weight: 700;
        text-align: left;
        cursor: pointer;
    }

    .mobile-account-logout:hover,
    .mobile-account-logout:focus-visible {
        background: #fff4ef;
        outline: none;
    }

    .course-reader-layout,
    .course-reader-sidebar,
    .course-reader-content {
        width: 100%;
        min-width: 0;
    }

    .course-reader-sidebar nav {
        max-width: 100%;
    }
}

@media (max-width: 560px) {
    .site-nav {
        position: sticky;
    }

    .article-toc > strong {
        display: none;
    }

    .article-toc-toggle {
        display: block;
    }

    .article-toc nav {
        display: none;
        margin-top: 12px;
    }

    .article-toc.is-open nav {
        display: grid;
    }
}

/* Keep reading headers and content in one continuous visual flow. */
.course-reader-content .course-reader-head {
    padding-bottom: 14px;
    border-bottom: 0;
}

.course-reader-content .article-body.course-chapter-body {
    margin: 0;
    padding: 12px 0 28px;
    border: 0;
    border-radius: 0;
    background: transparent;
    box-shadow: none;
}

.course-reader-layout > .course-reader-content {
    padding: 12px 12px 28px;
    border: 0;
    border-radius: 0;
    background: transparent;
    box-shadow: none;
}

.article-detail-section .article-body {
    padding: 38px;
    border: 1px solid var(--line);
    border-radius: 10px;
    background: #fff;
    box-shadow: 0 14px 34px rgba(47, 95, 150, 0.08);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) {
    font-size: 0.85rem;
    line-height: 1.8;
}

/* Match the compact, readable typography of the legacy article page without
   reintroducing a nested content card. */
:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) h1:not(.article-detail-title) {
    margin: 1.5rem 0 0.75rem;
    color: var(--ink);
    font-size: 1.5rem;
    line-height: 1.3;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) h2 {
    display: inline-block;
    margin: 1.5rem 0 0.75rem;
    padding: 0 0 0.5rem;
    border-bottom: 2px solid var(--blue);
    color: var(--ink);
    font-size: 1.25rem;
    line-height: 1.3;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) h3 {
    margin: 1.25rem 0 0.5rem;
    color: var(--ink);
    font-size: 1.1rem;
    line-height: 1.3;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) h4 {
    margin: 1rem 0 0.5rem;
    color: var(--ink);
    font-size: 1rem;
    line-height: 1.3;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) p:not(.article-detail-excerpt),
:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) li {
    color: #444;
    font-size: 0.85rem;
    line-height: 1.8;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) p:not(.article-detail-excerpt) {
    margin: 0 0 0.75rem;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) strong {
    color: var(--ink);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) ul,
:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) ol {
    margin: 1rem 0;
    padding-left: 1.5rem;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) li {
    margin-bottom: 0.35rem;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) li::marker {
    color: var(--blue);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) blockquote {
    margin: 1rem 0;
    padding: 0.75rem 1rem;
    border-left: 4px solid var(--blue);
    border-radius: 0 8px 8px 0;
    background: var(--soft);
    color: var(--muted);
    font-style: normal;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) pre {
    margin: 1rem 0;
    padding: 1rem;
    border-radius: 8px;
    background: #282c34;
    color: #abb2bf;
    font-size: 0.85rem;
    line-height: 1.5;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) code {
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    background: var(--soft);
    color: #e74c3c;
    font-size: 0.85em;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) pre code {
    padding: 0;
    background: transparent;
    color: inherit;
    font-size: inherit;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) img {
    max-width: 100%;
    margin: 1rem 0;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) a {
    color: var(--blue);
    text-decoration: none;
    border-bottom: 1px solid transparent;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) a:hover {
    border-bottom-color: var(--blue);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) table {
    width: 100%;
    margin: 1rem 0;
    border-collapse: collapse;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) th,
:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) td {
    padding: 0.75rem;
    border: 0;
    text-align: left;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) th {
    background: var(--ink);
    color: #fff;
    font-weight: 600;
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) tr:nth-child(even) {
    background: var(--soft);
}

:is(.article-detail-section .article-body, .course-reader-content .course-chapter-body) hr {
    margin: 1.5rem 0;
    border: 0;
    border-top: 2px solid var(--line);
}

@media (max-width: 560px) {
    .course-reader-layout > .course-reader-content {
        padding: 4px 0 24px;
    }

    .article-detail-section .article-body {
        padding: 20px;
    }
}