/* ============================================================
   GCCA 课程风采 · 公开展示页
   纸质编辑风：暖纸底 / 墨色 / 赭石强调 / 发丝线 / 大字号
   适配：桌面 1440+ / 笔记本 1024 / 平板 768 / 手机 430·390·375·360
   ============================================================ */

:root {
    --paper: #F6F2EA;
    --paper-2: #EFE8DB;
    --paper-3: #E7DECD;
    --ink: #17130F;
    --ink-2: #3A332B;
    --muted: #786D5F;
    --muted-2: #9A8F80;
    --line: rgba(23, 19, 15, .14);
    --line-soft: rgba(23, 19, 15, .08);
    --accent: #BC4A2B;
    --accent-dark: #9C3A20;
    --accent-soft: #F2DFD5;
    --nature: #4C6A45;
    --humanities: #6D5A8A;
    --innovation: #2C6C78;
    --aesthetic: #BC4A2B;
    --finance: #A9862F;
    --radius: 3px;
    --max: 1360px;
    --pad: clamp(20px, 4.4vw, 72px);
    --ease: cubic-bezier(.22, .61, .36, 1);
    --shadow-1: 0 1px 2px rgba(23, 19, 15, .05), 0 12px 32px -18px rgba(23, 19, 15, .35);
    --sans: "PingFang SC", "HarmonyOS Sans SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
    --serif: "Songti SC", "STSong", "Source Han Serif SC", Georgia, serif;
    --mono: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
html, body { margin: 0; padding: 0; }
body {
    background: var(--paper);
    color: var(--ink);
    font-family: var(--sans);
    font-size: 16px;
    line-height: 1.65;
    letter-spacing: .01em;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}
body.no-scroll { overflow: hidden; }
img, video { display: block; max-width: 100%; }
[hidden] { display: none !important; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; cursor: pointer; }
input, textarea, select { font: inherit; color: inherit; }
::selection { background: var(--ink); color: var(--paper); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

/* 纸张颗粒：极轻的噪点，避免大面积纯色发闷 */
.paper-grain {
    position: fixed;
    inset: 0;
    z-index: 1;
    pointer-events: none;
    opacity: .5;
    mix-blend-mode: multiply;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix type='saturate' values='0'/%3E%3C/filter%3E%3Crect width='160' height='160' filter='url(%23n)' opacity='.055'/%3E%3C/svg%3E");
}
.scroll-progress {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: 2px;
    z-index: 90;
    background: transparent;
    pointer-events: none;
}
.scroll-progress i {
    display: block;
    height: 100%;
    width: 0;
    background: var(--accent);
    transition: width .12s linear;
}

/* ---------- 通用 ---------- */
.wrap { width: 100%; max-width: var(--max); margin: 0 auto; padding-inline: var(--pad); }
.eyebrow {
    font-family: var(--mono);
    font-size: 11px;
    letter-spacing: .22em;
    text-transform: uppercase;
    color: var(--muted);
    margin: 0 0 18px;
}
.serif { font-family: var(--serif); font-style: italic; font-weight: 400; letter-spacing: 0; }
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    height: 46px;
    padding: 0 22px;
    border: 1px solid transparent;
    border-radius: 999px;
    font-size: 14px;
    font-weight: 600;
    letter-spacing: .02em;
    transition: background .25s var(--ease), color .25s var(--ease), border-color .25s var(--ease), transform .25s var(--ease);
    white-space: nowrap;
}
.btn svg { width: 16px; height: 16px; flex: 0 0 auto; }
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn-ink { background: var(--ink); color: var(--paper); }
.btn-ink:hover { background: #2B241D; }
.btn-accent { background: var(--accent); color: #fff; }
.btn-accent:hover { background: var(--accent-dark); }
.btn-quiet { background: transparent; border-color: var(--line); color: var(--ink); }
.btn-quiet:hover { background: var(--paper-2); }
.btn-block { width: 100%; }
.ghost-link {
    background: rgba(246, 242, 234, .08);
    border: 1px solid rgba(246, 242, 234, .34);
    border-radius: 999px;
    padding: 6px 14px;
    font-size: 12.5px;
    white-space: nowrap;
    flex: 0 0 auto;
    color: var(--paper);
    transition: border-color .2s, color .2s, background .2s;
}
.ghost-link:hover { border-color: rgba(246, 242, 234, .8); background: rgba(246, 242, 234, .14); }
.topbar.solid .ghost-link { background: transparent; border-color: var(--line); color: var(--ink-2); }
.topbar.solid .ghost-link:hover { border-color: var(--ink); color: var(--ink); }

/* ---------- 顶栏 ---------- */
.topbar {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 80;
    height: 76px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    padding: 0 var(--pad);
    color: var(--paper);
    transition: background .35s var(--ease), color .35s var(--ease), height .35s var(--ease), border-color .35s;
    border-bottom: 1px solid transparent;
}
.topbar.solid {
    height: 64px;
    background: rgba(246, 242, 234, .92);
    -webkit-backdrop-filter: saturate(140%) blur(14px);
    backdrop-filter: saturate(140%) blur(14px);
    color: var(--ink);
    border-bottom-color: var(--line-soft);
}
.brand { display: inline-flex; align-items: center; gap: 11px; min-width: 0; }
.brand-mark { width: 30px; height: 30px; flex: 0 0 auto; }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text b { font-size: 15px; font-weight: 700; letter-spacing: .04em; }
.brand-text i { font-style: normal; font-size: 10.5px; letter-spacing: .24em; opacity: .62; margin-top: 2px; }
.nav { display: flex; align-items: center; gap: 30px; }
.nav a {
    position: relative;
    font-size: 13.5px;
    letter-spacing: .06em;
    opacity: .82;
    padding: 6px 0;
    transition: opacity .2s;
}
.nav a::after {
    content: "";
    position: absolute;
    left: 0; right: 100%;
    bottom: 0;
    height: 1px;
    background: currentColor;
    transition: right .3s var(--ease);
}
.nav a:hover { opacity: 1; }
.nav a:hover::after { right: 0; }
.top-actions { display: flex; align-items: center; gap: 18px; }
.topbar .btn-ink { background: var(--paper); color: var(--ink); }
.topbar .btn-ink:hover { background: #fff; }
.topbar.solid .btn-ink { background: var(--ink); color: var(--paper); }

/* ---------- Hero ---------- */
.hero {
    position: relative;
    min-height: 100svh;
    display: flex;
    align-items: flex-end;
    overflow: hidden;
    background: #191410;
    color: var(--paper);
    isolation: isolate;
}
.hero-media { position: absolute; inset: 0; z-index: 0; }
.hero-media img,
.hero-media video {
    width: 100%; height: 100%;
    object-fit: cover;
    transform: scale(1.04);
    filter: saturate(.92) contrast(1.02) brightness(.86);
    animation: heroDrift 18s var(--ease) forwards;
}
@keyframes heroDrift { to { transform: scale(1); } }
.hero-media::after {
    content: "";
    position: absolute;
    inset: 0;
    background:
        linear-gradient(180deg, rgba(14, 11, 8, .62) 0%, rgba(14, 11, 8, .22) 34%, rgba(14, 11, 8, .40) 62%, rgba(14, 11, 8, .9) 100%),
        linear-gradient(90deg, rgba(12, 9, 6, .66) 0%, rgba(12, 9, 6, .30) 48%, rgba(12, 9, 6, .04) 78%),
        radial-gradient(120% 80% at 18% 90%, rgba(188, 74, 43, .20), transparent 60%);
}
.media-skeleton {
    width: 100%; height: 100%;
    background: linear-gradient(110deg, #241C16 8%, #32261D 18%, #241C16 33%);
    background-size: 200% 100%;
    animation: shimmer 1.7s linear infinite;
}
@keyframes shimmer { to { background-position: -200% 0; } }
.hero-inner {
    position: relative;
    z-index: 2;
    width: 100%;
    max-width: var(--max);
    margin: 0 auto;
    padding: 0 var(--pad) clamp(48px, 9vh, 96px);
}
.hero-kicker {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    margin: 0 0 26px;
    font-size: 12px;
    letter-spacing: .28em;
    text-transform: uppercase;
    opacity: .82;
}
.hero-kicker .dot {
    width: 6px; height: 6px; border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 4px rgba(188, 74, 43, .18);
}
.hero-title {
    margin: 0;
    font-size: clamp(40px, 7.1vw, 108px);
    line-height: 1.0;
    letter-spacing: -.03em;
    font-weight: 600;
    max-width: 16ch;
    text-wrap: balance;
}
.hero-title .serif { color: #E9B79E; }
.hero-sub {
    margin: 30px 0 0;
    max-width: 46ch;
    font-size: clamp(14px, 1.25vw, 17px);
    line-height: 1.85;
    color: rgba(246, 242, 234, .82);
}
.hero-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 14px 28px;
    margin-top: 36px;
}
.hero-meta .btn { height: 50px; padding: 0 28px; }
.hero .btn-quiet, .detail-hero .btn-quiet { color: var(--paper); border-color: rgba(246, 242, 234, .34); background: transparent; }
.hero .btn-quiet:hover, .detail-hero .btn-quiet:hover { background: rgba(246, 242, 234, .1); border-color: rgba(246, 242, 234, .7); }
.hero-stats {
    display: flex;
    gap: clamp(20px, 4vw, 54px);
    margin-top: 54px;
    padding-top: 24px;
    border-top: 1px solid rgba(246, 242, 234, .20);
    max-width: 760px;
}
.hero-stat b {
    display: block;
    font-family: var(--mono);
    font-size: clamp(22px, 2.6vw, 34px);
    line-height: 1;
    font-weight: 500;
    letter-spacing: -.02em;
}
.hero-stat span { display: block; margin-top: 8px; font-size: 11.5px; letter-spacing: .16em; opacity: .62; }
.hero-side {
    position: absolute;
    right: var(--pad);
    bottom: clamp(48px, 9vh, 96px);
    z-index: 2;
    writing-mode: vertical-rl;
    font-size: 11px;
    letter-spacing: .3em;
    opacity: .55;
}
.hero-scroll {
    position: absolute;
    left: 50%;
    bottom: 22px;
    transform: translateX(-50%);
    z-index: 2;
    width: 18px; height: 30px;
    border: 1px solid rgba(246, 242, 234, .4);
    border-radius: 10px;
    display: flex;
    justify-content: center;
    padding-top: 5px;
}
.hero-scroll i {
    display: block;
    width: 3px; height: 6px;
    background: rgba(246, 242, 234, .8);
    border-radius: 2px;
    animation: scrollHint 1.8s infinite;
}
@keyframes scrollHint { 0% { opacity: 0; transform: translateY(0); } 40% { opacity: 1; } 100% { opacity: 0; transform: translateY(9px); } }

/* 跑马灯 */
.marquee {
    position: relative;
    overflow: hidden;
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    background: var(--paper-2);
}
.marquee-track {
    display: flex;
    gap: 0;
    width: max-content;
    animation: marquee 42s linear infinite;
}
.marquee:hover .marquee-track { animation-play-state: paused; }
.marquee span {
    display: inline-flex;
    align-items: center;
    gap: 22px;
    padding: 13px 0;
    font-size: 12px;
    letter-spacing: .22em;
    text-transform: uppercase;
    color: var(--ink-2);
    white-space: nowrap;
}
.marquee span::before { content: "◇"; color: var(--accent); padding: 0 22px; font-size: 10px; }
@keyframes marquee { to { transform: translateX(-50%); } }

/* ---------- 章节 ---------- */
.section { position: relative; padding: clamp(72px, 10vw, 140px) 0; }
.section + .section { border-top: 1px solid var(--line-soft); }
.section-head {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: 40px;
    margin-bottom: clamp(36px, 5vw, 64px);
}
.section-head h2 {
    margin: 0;
    font-size: clamp(30px, 4.2vw, 56px);
    line-height: 1.14;
    letter-spacing: -.025em;
    font-weight: 600;
    max-width: 22ch;
}
.section-head h2 em { font-family: var(--serif); font-weight: 400; color: var(--accent); font-style: italic; }
.section-head .lead {
    max-width: 40ch;
    margin: 14px 0 0;
    font-size: 14.5px;
    line-height: 1.9;
    color: var(--muted);
}
.section-index {
    flex: 0 0 auto;
    font-family: var(--mono);
    font-size: 12px;
    letter-spacing: .14em;
    color: var(--muted);
    padding-bottom: 8px;
    border-bottom: 1px solid var(--line);
}
.section-head-right { display: flex; flex-direction: column; align-items: flex-end; gap: 14px; }

/* ---------- 五维 ---------- */
.dims { display: grid; grid-template-columns: repeat(5, 1fr); gap: 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.dim {
    position: relative;
    padding: 30px 22px 26px;
    border-right: 1px solid var(--line);
    background: transparent;
    text-align: left;
    transition: background .35s var(--ease), color .35s var(--ease);
    min-height: 210px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}
.dim:last-child { border-right: 0; }
.dim:hover { background: var(--ink); color: var(--paper); }
.dim-num { display: block; font-family: var(--mono); font-size: 11px; letter-spacing: .16em; opacity: .55; }
.dim-name { display: block; font-size: clamp(22px, 2.2vw, 30px); font-weight: 600; letter-spacing: -.02em; margin-top: 18px; line-height: 1.1; }
.dim-en { display: block; font-family: var(--mono); font-size: 10px; letter-spacing: .22em; opacity: .5; margin-top: 6px; }
.dim-desc { display: block; margin-top: 18px; font-size: 12.5px; line-height: 1.7; color: var(--muted); transition: color .35s; }
.dim:hover .dim-desc { color: rgba(246, 242, 234, .66); }
.dim-count { margin-top: 18px; font-family: var(--mono); font-size: 11px; letter-spacing: .1em; opacity: .7; }
.dim::before {
    content: "";
    position: absolute;
    left: 0; top: 0;
    width: 100%; height: 2px;
    background: var(--accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform .4s var(--ease);
}
.dim:hover::before { transform: scaleX(1); }

/* ---------- 课程 ---------- */
.filter-row { display: flex; flex-wrap: wrap; gap: 8px; }
.filter-chip {
    height: 34px;
    padding: 0 16px;
    border-radius: 999px;
    border: 1px solid var(--line);
    background: transparent;
    font-size: 12.5px;
    letter-spacing: .02em;
    color: var(--ink-2);
    transition: all .2s var(--ease);
}
.filter-chip:hover { border-color: var(--ink); }
.filter-chip.active { background: var(--ink); border-color: var(--ink); color: var(--paper); }

.course-list { display: grid; grid-template-columns: repeat(12, 1fr); gap: clamp(14px, 1.8vw, 24px); }
.course-card {
    grid-column: span 4;
    position: relative;
    display: flex;
    flex-direction: column;
    background: #FBF8F2;
    border: 1px solid var(--line);
    overflow: hidden;
    transition: transform .45s var(--ease), box-shadow .45s var(--ease), border-color .3s;
}
.course-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-1); border-color: rgba(23, 19, 15, .26); }
.course-card.is-featured { grid-column: span 12; display: grid; grid-template-columns: 1.35fr 1fr; }
.cc-media {
    position: relative;
    overflow: hidden;
    aspect-ratio: 4 / 3;
    background: var(--paper-3);
}
.course-card.is-featured .cc-media { aspect-ratio: auto; min-height: 430px; height: 100%; }
.course-card.is-featured .cc-media img { position: absolute; inset: 0; width: 100%; height: 100%; }
.cc-media img {
    width: 100%; height: 100%;
    object-fit: cover;
    transition: transform 1.1s var(--ease), filter .5s;
    filter: saturate(.96);
}
.course-card:hover .cc-media img { transform: scale(1.045); filter: saturate(1.04); }
.cc-media .cc-tag {
    position: absolute;
    left: 14px; top: 14px;
    display: inline-flex;
    align-items: center;
    gap: 7px;
    height: 27px;
    padding: 0 11px;
    background: rgba(246, 242, 234, .92);
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
    border-radius: 999px;
    font-size: 11px;
    letter-spacing: .08em;
    color: var(--ink);
}
.cc-media .cc-tag i { width: 5px; height: 5px; border-radius: 50%; background: var(--accent); }
.cc-media .cc-placeholder {
    width: 100%; height: 100%;
    display: flex; align-items: center; justify-content: center;
    background:
        repeating-linear-gradient(135deg, rgba(23,19,15,.045) 0 1px, transparent 1px 9px),
        var(--paper-2);
    color: var(--muted-2);
    font-family: var(--mono);
    font-size: 11px;
    letter-spacing: .2em;
}
.cc-body { padding: clamp(20px, 2.2vw, 32px); display: flex; flex-direction: column; flex: 1; }
.course-card.is-featured .cc-body { justify-content: center; padding: clamp(28px, 3.4vw, 54px); }
.cc-kicker { display: flex; align-items: center; gap: 12px; font-family: var(--mono); font-size: 10.5px; letter-spacing: .18em; color: var(--muted); text-transform: uppercase; }
.cc-kicker span { opacity: .5; }
.cc-title {
    margin: 14px 0 0;
    font-size: clamp(20px, 2vw, 27px);
    line-height: 1.22;
    letter-spacing: -.02em;
    font-weight: 600;
}
.course-card.is-featured .cc-title { font-size: clamp(28px, 3.2vw, 44px); }
.cc-sub { margin: 10px 0 0; font-size: 13.5px; line-height: 1.8; color: var(--muted); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.course-card.is-featured .cc-sub { -webkit-line-clamp: 3; font-size: 14.5px; max-width: 42ch; }
.cc-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 6px 16px;
    margin-top: auto;
    padding-top: 22px;
    font-size: 12px;
    color: var(--muted);
}
.cc-meta b { color: var(--ink); font-weight: 600; }
.cc-foot { display: flex; align-items: center; justify-content: space-between; margin-top: 18px; padding-top: 16px; border-top: 1px solid var(--line-soft); }
.cc-go { display: inline-flex; align-items: center; gap: 8px; font-size: 12.5px; font-weight: 600; letter-spacing: .04em; }
.cc-go svg { width: 15px; height: 15px; transition: transform .3s var(--ease); }
.course-card:hover .cc-go svg { transform: translateX(4px); }
.cc-tags { display: flex; gap: 6px; flex-wrap: wrap; }
.cc-tags i { font-style: normal; font-size: 10.5px; letter-spacing: .06em; color: var(--muted); border: 1px solid var(--line); padding: 2px 8px; border-radius: 999px; }
.course-cta {
    grid-column: span 4;
    text-align: left;
    border: 1px dashed var(--line);
    background: rgba(255, 255, 255, .22);
    padding: 26px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    min-height: 260px;
    transition: background .3s, border-color .3s;
}
.course-cta:hover { background: rgba(255, 255, 255, .6); border-color: var(--ink); }
.course-cta.span8 { grid-column: span 8; }
.course-cta b { font-size: clamp(19px, 1.8vw, 23px); letter-spacing: -.02em; line-height: 1.35; }
.course-cta em { display: block; margin-top: 10px; font-style: normal; font-size: 12.5px; line-height: 1.8; color: var(--muted); }
.course-cta > span:first-child { display: block; }
.course-cta > span:last-child { display: inline-flex; align-items: center; gap: 8px; font-size: 12.5px; font-weight: 600; margin-top: 20px; }
.course-cta svg { width: 15px; height: 15px; }

/* ---------- 学习成果 / 图集 ---------- */
.gallery-tools { display: flex; align-items: center; gap: 16px; }
.gallery { columns: 3; column-gap: clamp(12px, 1.6vw, 20px); }
.gal-item {
    position: relative;
    break-inside: avoid;
    margin-bottom: clamp(12px, 1.6vw, 20px);
    overflow: hidden;
    background: var(--paper-3);
    cursor: zoom-in;
}
.gal-item img {
    width: 100%;
    height: auto;
    min-height: 120px;
    transition: transform .9s var(--ease), filter .4s;
    filter: saturate(.96);
}
.gal-item:hover img { transform: scale(1.035); filter: saturate(1.05); }
.gal-item .gal-cap {
    position: absolute;
    left: 0; right: 0; bottom: 0;
    padding: 34px 14px 12px;
    background: linear-gradient(transparent, rgba(14, 11, 8, .72));
    color: var(--paper);
    font-size: 12px;
    opacity: 0;
    transform: translateY(6px);
    transition: all .35s var(--ease);
}
.gal-item:hover .gal-cap { opacity: 1; transform: none; }
.gal-item.is-video::after {
    content: "";
    position: absolute;
    top: 12px; right: 12px;
    width: 30px; height: 30px;
    border-radius: 50%;
    background: rgba(246, 242, 234, .92) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 20 20'%3E%3Cpath d='M8 6.4 14 10l-6 3.6z' fill='%2317130F'/%3E%3C/svg%3E") center/16px no-repeat;
    -webkit-backdrop-filter: blur(6px);
    backdrop-filter: blur(6px);
}
.gal-video-ph {
    width: 100%;
    aspect-ratio: 16 / 11;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background:
        repeating-linear-gradient(135deg, rgba(246, 242, 234, .05) 0 1px, transparent 1px 10px),
        linear-gradient(160deg, #2A231C, #17130F);
    color: rgba(246, 242, 234, .82);
}
.gal-video-ph svg { width: 34px; height: 34px; }
.gal-video-ph b { font-size: 11px; letter-spacing: .2em; font-weight: 500; }
.gal-item .gal-video-badge {
    position: absolute;
    left: 12px; bottom: 12px;
    display: inline-flex;
    align-items: center;
    height: 22px;
    padding: 0 9px;
    border-radius: 999px;
    background: rgba(14, 11, 8, .55);
    color: #fff;
    font-size: 10px;
    letter-spacing: .1em;
}
.gallery-more { display: flex; justify-content: center; margin-top: 34px; }

/* ---------- 系列视频 ---------- */
.video-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: clamp(16px, 2vw, 28px); }
.video-card { display: flex; flex-direction: column; }
.video-cover {
    position: relative;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: var(--paper-3);
    cursor: pointer;
}
.video-cover img { width: 100%; height: 100%; object-fit: cover; transition: transform .9s var(--ease); }
.video-card:hover .video-cover img { transform: scale(1.04); }
.video-cover .play {
    position: absolute;
    left: 50%; top: 50%;
    transform: translate(-50%, -50%);
    width: 54px; height: 54px;
    border-radius: 50%;
    border: 1px solid rgba(246, 242, 234, .7);
    background: rgba(14, 11, 8, .28);
    -webkit-backdrop-filter: blur(6px);
    backdrop-filter: blur(6px);
    display: flex; align-items: center; justify-content: center;
    transition: background .25s, transform .35s var(--ease);
}
.video-cover .play svg { width: 18px; height: 18px; fill: #fff; margin-left: 3px; }
.video-card:hover .play { background: var(--accent); border-color: var(--accent); transform: translate(-50%, -50%) scale(1.06); }
.video-cover .vid-dur {
    position: absolute;
    right: 10px; bottom: 10px;
    padding: 2px 8px;
    border-radius: 3px;
    background: rgba(14, 11, 8, .68);
    color: #fff;
    font-family: var(--mono);
    font-size: 10.5px;
    letter-spacing: .06em;
}
.video-body { padding-top: 14px; }
.video-series { font-family: var(--mono); font-size: 10px; letter-spacing: .18em; text-transform: uppercase; color: var(--accent); }
.video-title { margin: 8px 0 0; font-size: 16px; font-weight: 600; line-height: 1.4; letter-spacing: -.01em; }
.video-sum { margin: 6px 0 0; font-size: 12.5px; line-height: 1.75; color: var(--muted); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.video-empty {
    border: 1px dashed var(--line);
    padding: clamp(30px, 5vw, 56px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 30px;
    background: rgba(255, 255, 255, .28);
}
.video-empty b { font-size: clamp(19px, 2vw, 24px); letter-spacing: -.01em; }
.video-empty p { margin: 8px 0 0; font-size: 13px; color: var(--muted); }
.video-empty .stamp {
    flex: 0 0 auto;
    width: 92px; height: 92px;
    border: 1px solid var(--accent);
    border-radius: 50%;
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    font-family: var(--mono);
    font-size: 10px;
    letter-spacing: .16em;
    line-height: 1.6;
    transform: rotate(-8deg);
}

/* ---------- 关于 / FAQ ---------- */
.about-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(30px, 6vw, 90px); align-items: start; }
.about-statement {
    font-size: clamp(22px, 2.7vw, 34px);
    line-height: 1.55;
    letter-spacing: -.015em;
    font-weight: 500;
    margin: 0;
    text-wrap: pretty;
}
.about-statement em { font-family: var(--serif); font-style: italic; color: var(--accent); font-weight: 400; }
.about-points { margin: 34px 0 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
.about-points li { display: flex; gap: 18px; padding: 16px 0; border-bottom: 1px solid var(--line-soft); font-size: 13.5px; color: var(--ink-2); }
.about-points li span { font-family: var(--mono); font-size: 10.5px; color: var(--muted); padding-top: 3px; }
.faq-list { border-top: 1px solid var(--line); }
.faq-item { border-bottom: 1px solid var(--line-soft); }
.faq-item summary {
    list-style: none;
    cursor: pointer;
    padding: 18px 34px 18px 0;
    position: relative;
    font-size: 14.5px;
    font-weight: 500;
    line-height: 1.6;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
    content: "";
    position: absolute;
    right: 4px; top: 50%;
    width: 12px; height: 12px;
    margin-top: -6px;
    background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12'%3E%3Cpath d='M2 6h8M6 2v8' stroke='%2317130F' stroke-width='1.2' stroke-linecap='round'/%3E%3C/svg%3E") center/12px no-repeat;
    transition: transform .3s var(--ease);
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { margin: 0; padding: 0 34px 20px 0; font-size: 13.5px; line-height: 1.85; color: var(--muted); }
.contact-card {
    margin-top: 28px;
    border: 1px solid var(--line);
    padding: 22px;
    background: rgba(255, 255, 255, .34);
    display: grid;
    gap: 12px;
}
.contact-row { display: flex; gap: 14px; font-size: 13px; }
.contact-row b { flex: 0 0 60px; font-weight: 500; color: var(--muted); font-size: 12px; letter-spacing: .08em; }
.contact-row span { color: var(--ink-2); }

/* ---------- 页脚 ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--paper-2); padding: 46px 0 40px; }
.footer-inner {
    max-width: var(--max);
    margin: 0 auto;
    padding-inline: var(--pad);
    display: flex;
    flex-wrap: wrap;
    align-items: flex-start;
    justify-content: space-between;
    gap: 26px;
}
.footer-brand b { font-size: 15px; letter-spacing: .05em; }
.footer-brand p { margin: 8px 0 0; font-size: 12px; color: var(--muted); }
.footer-links { display: flex; gap: 22px; font-size: 12.5px; color: var(--ink-2); }
.footer-links a:hover { color: var(--accent); }
.footer-legal { display: flex; flex-direction: column; gap: 4px; font-size: 11.5px; color: var(--muted-2); text-align: right; }

/* ---------- 详情页 ---------- */
.detail-hero { position: relative; min-height: 74svh; display: flex; align-items: flex-end; background: #191410; color: var(--paper); overflow: hidden; }
.detail-hero .hero-media img { animation-duration: 22s; }
.detail-hero .hero-inner { padding-top: 120px; }
.detail-hero .crumbs { display: flex; align-items: center; gap: 10px; font-size: 11.5px; letter-spacing: .12em; opacity: .68; margin-bottom: 26px; }
.detail-hero .crumbs a:hover { opacity: 1; text-decoration: underline; text-underline-offset: 4px; }
.detail-hero h1 { font-size: clamp(34px, 5.4vw, 76px); line-height: 1.04; letter-spacing: -.03em; margin: 0; font-weight: 600; max-width: 20ch; text-wrap: balance; }
.detail-hero .dh-sub { margin: 20px 0 0; max-width: 54ch; font-size: 15px; line-height: 1.85; color: rgba(246, 242, 234, .8); }
.detail-facts { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.detail-facts span {
    display: inline-flex; align-items: center; gap: 8px;
    height: 34px; padding: 0 14px;
    border: 1px solid rgba(246, 242, 234, .26);
    border-radius: 999px;
    font-size: 12px;
    letter-spacing: .04em;
}
.detail-facts b { font-weight: 600; }
.detail-body { display: grid; grid-template-columns: 1.4fr .6fr; gap: clamp(30px, 5vw, 80px); align-items: start; }
.prose p { margin: 0 0 18px; font-size: 15.5px; line-height: 1.95; color: var(--ink-2); }
.prose p:last-child { margin-bottom: 0; }
.detail-aside { position: sticky; top: 96px; display: grid; gap: 22px; }
.aside-card { border: 1px solid var(--line); padding: 24px; background: rgba(255, 255, 255, .34); }
.aside-card h4 { margin: 0 0 16px; font-size: 12px; letter-spacing: .18em; text-transform: uppercase; color: var(--muted); font-weight: 500; }
.aside-list { margin: 0; padding: 0; list-style: none; display: grid; gap: 14px; }
.aside-list li { display: flex; justify-content: space-between; gap: 12px; font-size: 13px; border-bottom: 1px solid var(--line-soft); padding-bottom: 12px; }
.aside-list li:last-child { border-bottom: 0; padding-bottom: 0; }
.aside-list span { color: var(--muted); }
.highlight-list { counter-reset: hl; display: grid; gap: 0; border-top: 1px solid var(--line); }
.highlight-list li { counter-increment: hl; display: grid; grid-template-columns: 56px 1fr; gap: 18px; padding: 20px 0; border-bottom: 1px solid var(--line-soft); list-style: none; }
.highlight-list li::before { content: counter(hl, decimal-leading-zero); font-family: var(--mono); font-size: 12px; color: var(--accent); padding-top: 3px; }
.highlight-list b { display: block; font-size: 15px; font-weight: 600; }
.highlight-list span { display: block; margin-top: 5px; font-size: 13px; line-height: 1.8; color: var(--muted); }
.outcome-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.outcome-item { border: 1px solid var(--line); padding: 20px; background: rgba(255, 255, 255, .3); }
.outcome-item b { display: block; font-size: 14.5px; margin-bottom: 7px; }
.outcome-item p { margin: 0; font-size: 12.5px; line-height: 1.8; color: var(--muted); }
.chapter-list { display: grid; gap: 10px; }
.chapter-item { display: flex; align-items: center; gap: 14px; padding: 12px; border: 1px solid var(--line); background: rgba(255, 255, 255, .3); }
.chapter-item img { width: 66px; height: 48px; object-fit: cover; flex: 0 0 auto; }
.chapter-item span { font-size: 13px; }
.chapter-item i { margin-left: auto; font-style: normal; font-family: var(--mono); font-size: 10.5px; color: var(--muted); }
.detail-cta { display: flex; gap: 12px; }
.detail-bar { display: none; }
@media (max-width: 860px) {
    .detail-bar {
        display: flex;
        position: fixed;
        left: 0; right: 0; bottom: 0;
        z-index: 96;
        gap: 8px;
        padding: 10px 14px calc(10px + env(safe-area-inset-bottom));
        background: rgba(246, 242, 234, .96);
        -webkit-backdrop-filter: blur(12px);
        backdrop-filter: blur(12px);
        border-top: 1px solid var(--line);
    }
    .detail-bar .btn { flex: 1; height: 44px; }
    body.has-detail-bar .chat-dock { bottom: calc(86px + env(safe-area-inset-bottom)); }
    body.has-detail-bar #view { padding-bottom: 78px; }
    body.has-detail-bar .site-footer { padding-bottom: 84px; }
}
.reading-line { position: fixed; left: 0; top: 0; bottom: 0; width: 3px; background: var(--accent); transform-origin: top; transform: scaleY(0); z-index: 70; opacity: .7; }

/* ---------- 灯箱 ---------- */
.lightbox {
    position: fixed;
    inset: 0;
    z-index: 120;
    background: rgba(12, 10, 8, .96);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 4vh 6vw;
    color: var(--paper);
}
.lightbox[hidden] { display: none; }
.lb-stage { margin: 0; max-width: 100%; max-height: 100%; display: flex; flex-direction: column; align-items: center; gap: 14px; }
.lb-stage img { max-width: 90vw; max-height: 78vh; width: auto; height: auto; object-fit: contain; }
.lb-stage video { max-width: 90vw; max-height: 78vh; background: #000; }
.lb-stage figcaption { font-size: 12.5px; color: rgba(246, 242, 234, .7); text-align: center; max-width: 70ch; }
.lb-close, .lb-nav {
    position: absolute;
    background: transparent;
    border: 1px solid rgba(246, 242, 234, .28);
    border-radius: 50%;
    width: 44px; height: 44px;
    display: flex; align-items: center; justify-content: center;
    color: var(--paper);
    transition: background .2s, border-color .2s;
}
.lb-close:hover, .lb-nav:hover { background: rgba(246, 242, 234, .12); border-color: rgba(246, 242, 234, .6); }
.lb-close { top: 22px; right: 22px; }
.lb-close svg, .lb-nav svg { width: 18px; height: 18px; }
.lb-prev { left: 18px; top: 50%; transform: translateY(-50%); }
.lb-next { right: 18px; top: 50%; transform: translateY(-50%); }
.lb-meta { position: absolute; left: 24px; bottom: 20px; right: 24px; display: flex; justify-content: space-between; gap: 20px; font-family: var(--mono); font-size: 11px; letter-spacing: .1em; color: rgba(246, 242, 234, .55); }

/* ---------- 弹层 / 表单 ---------- */
.sheet { position: fixed; inset: 0; z-index: 130; display: flex; align-items: center; justify-content: center; padding: 20px; }
.sheet[hidden] { display: none; }
.sheet-mask { position: absolute; inset: 0; background: rgba(14, 11, 8, .55); -webkit-backdrop-filter: blur(4px); backdrop-filter: blur(4px); animation: fadeIn .25s var(--ease); }
@keyframes fadeIn { from { opacity: 0; } }
.sheet-card {
    position: relative;
    width: min(980px, 100%);
    max-height: 92svh;
    overflow: auto;
    background: var(--paper);
    display: grid;
    grid-template-columns: .88fr 1.12fr;
    gap: 0;
    box-shadow: 0 40px 120px -40px rgba(0, 0, 0, .6);
    animation: sheetUp .35s var(--ease);
    -webkit-overflow-scrolling: touch;
}
.sheet-card-narrow { width: min(560px, 100%); grid-template-columns: 1fr; }
@keyframes sheetUp { from { opacity: 0; transform: translateY(18px); } }
.sheet-close {
    position: absolute;
    right: 14px; top: 14px;
    width: 38px; height: 38px;
    border: 0;
    background: transparent;
    color: var(--muted);
    display: flex; align-items: center; justify-content: center;
    z-index: 2;
}
.sheet-close svg { width: 18px; height: 18px; }
.sheet-copy {
    padding: clamp(30px, 3.4vw, 50px);
    background: var(--ink);
    color: var(--paper);
    display: flex;
    flex-direction: column;
}
.sheet-copy .eyebrow { color: rgba(246, 242, 234, .5); }
.sheet-copy h2 { margin: 0 0 18px; font-size: clamp(24px, 2.6vw, 34px); line-height: 1.28; letter-spacing: -.02em; font-weight: 600; }
.sheet-note { margin: 0; font-size: 13px; line-height: 1.85; color: rgba(246, 242, 234, .62); }
.join-points { margin: 34px 0 0; padding: 0; list-style: none; display: grid; gap: 16px; }
.join-points li { display: flex; gap: 14px; font-size: 12.5px; line-height: 1.7; color: rgba(246, 242, 234, .76); }
.join-points li span { font-family: var(--mono); font-size: 10px; color: #D99279; padding-top: 3px; }
.sheet-form { padding: clamp(30px, 3.4vw, 46px); }
.need-title { margin: 0 0 12px; font-size: clamp(23px, 2.4vw, 30px); line-height: 1.3; letter-spacing: -.02em; font-weight: 600; }
.tabs { display: flex; gap: 26px; border-bottom: 1px solid var(--line); margin-bottom: 26px; }
.tab { position: relative; background: none; border: 0; padding: 0 0 12px; font-size: 13.5px; color: var(--muted); }
.tab.active { color: var(--ink); font-weight: 600; }
.tab.active::after { content: ""; position: absolute; left: 0; right: 0; bottom: -1px; height: 2px; background: var(--ink); }
.field { display: block; margin-bottom: 16px; }
.field > span { display: block; font-size: 11.5px; letter-spacing: .1em; color: var(--muted); margin-bottom: 7px; }
.field input, .field textarea {
    width: 100%;
    border: 1px solid var(--line);
    background: #FCFAF5;
    border-radius: 2px;
    padding: 11px 13px;
    font-size: 14px;
    line-height: 1.5;
    transition: border-color .2s, background .2s, box-shadow .2s;
}
.field textarea { resize: vertical; min-height: 82px; }
.field input:focus, .field textarea:focus {
    outline: none;
    border-color: var(--ink);
    background: #fff;
    box-shadow: 0 0 0 3px rgba(23, 19, 15, .06);
}
.field input::placeholder, .field textarea::placeholder { color: #B4A999; }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
    height: 34px;
    padding: 0 14px;
    border: 1px solid var(--line);
    background: transparent;
    border-radius: 999px;
    font-size: 12.5px;
    color: var(--ink-2);
    transition: all .2s;
}
.chip.on { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.agree { display: flex; gap: 10px; align-items: flex-start; font-size: 12px; color: var(--muted); line-height: 1.7; margin: 6px 0 18px; }
.agree input { margin-top: 3px; width: 15px; height: 15px; accent-color: var(--accent); flex: 0 0 auto; }
.agree a { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }
.form-error { min-height: 18px; font-size: 12px; color: #B23B1E; margin-bottom: 8px; }
.form-tip { margin: 14px 0 0; font-size: 11.5px; line-height: 1.7; color: var(--muted-2); }
.form-success { text-align: center; padding: 28px 0 8px; }
.form-success .ok-mark { width: 54px; height: 54px; border-radius: 50%; border: 1px solid var(--accent); color: var(--accent); display: flex; align-items: center; justify-content: center; margin: 0 auto 20px; }
.form-success .ok-mark svg { width: 24px; height: 24px; }
.form-success h3 { margin: 0 0 10px; font-size: 22px; letter-spacing: -.01em; }
.form-success p { margin: 0 0 22px; font-size: 13px; line-height: 1.8; color: var(--muted); }
.form-success .btn + .btn { margin-top: 10px; }

/* ---------- 课程小助手 ---------- */
.chat-dock { position: fixed; right: 22px; bottom: 22px; z-index: 100; }
.chat-fab {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    height: 50px;
    padding: 0 20px 0 12px;
    border-radius: 999px;
    border: 1px solid rgba(246, 242, 234, .18);
    background: var(--ink);
    color: var(--paper);
    box-shadow: 0 14px 34px -16px rgba(23, 19, 15, .8);
    transition: transform .25s var(--ease), background .25s;
}
.chat-fab:hover { transform: translateY(-2px); background: #2B241D; }
.chat-fab-ic { display: flex; width: 28px; height: 28px; align-items: center; justify-content: center; }
.chat-fab-ic svg { width: 21px; height: 21px; }
.chat-fab-text { font-size: 13.5px; letter-spacing: .04em; }
.chat-fab-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }
.chat-fab-dot[hidden] { display: none; }
.chat-panel {
    position: absolute;
    right: 0;
    bottom: 64px;
    width: 392px;
    max-width: calc(100vw - 44px);
    height: min(620px, calc(100svh - 110px));
    background: var(--paper);
    border: 1px solid var(--line);
    box-shadow: 0 30px 80px -30px rgba(23, 19, 15, .55);
    display: flex;
    flex-direction: column;
    animation: sheetUp .28s var(--ease);
}
.chat-panel[hidden] { display: none; }
.chat-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 14px 16px;
    background: var(--ink);
    color: var(--paper);
    flex: 0 0 auto;
}
.chat-who { display: flex; align-items: center; gap: 11px; min-width: 0; }
.chat-avatar { width: 34px; height: 34px; border-radius: 50%; border: 1px solid rgba(246, 242, 234, .3); display: flex; align-items: center; justify-content: center; flex: 0 0 auto; }
.chat-avatar svg { width: 20px; height: 20px; }
.chat-who b { display: block; font-size: 13.5px; font-weight: 600; }
.chat-who i { display: block; font-style: normal; font-size: 10.5px; letter-spacing: .08em; color: rgba(246, 242, 234, .55); margin-top: 2px; }
.chat-close { background: none; border: 0; color: rgba(246, 242, 234, .7); width: 30px; height: 30px; display: flex; align-items: center; justify-content: center; }
.chat-close svg { width: 16px; height: 16px; }
.chat-body { flex: 1; overflow-y: auto; padding: 16px; -webkit-overflow-scrolling: touch; }
.chat-intro { border: 1px solid var(--line); padding: 13px 14px; margin-bottom: 12px; font-size: 12.5px; line-height: 1.75; color: var(--ink-2); background: rgba(255, 255, 255, .4); }
.chat-intro b { color: var(--ink); }
.chat-need-row { margin-top: 10px; }
.chat-need-row button {
    height: 30px;
    padding: 0 12px;
    border: 1px solid var(--ink);
    background: transparent;
    border-radius: 999px;
    font-size: 11.5px;
    color: var(--ink);
}
.chat-need-row button:hover { background: var(--ink); color: var(--paper); }
.chat-quick { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 14px; }
.chat-quick button {
    border: 1px solid var(--line);
    background: transparent;
    border-radius: 999px;
    padding: 5px 11px;
    font-size: 11.5px;
    color: var(--ink-2);
    transition: all .2s;
    text-align: left;
}
.chat-quick button:hover { border-color: var(--ink); background: #fff; }
.chat-log { display: flex; flex-direction: column; gap: 12px; }
.msg { max-width: 86%; font-size: 13px; line-height: 1.75; padding: 10px 13px; white-space: pre-wrap; word-break: break-word; }
.msg.user { align-self: flex-end; background: var(--ink); color: var(--paper); border-radius: 10px 10px 2px 10px; }
.msg.bot { align-self: flex-start; background: #fff; border: 1px solid var(--line); border-radius: 10px 10px 10px 2px; }
.msg.typing { color: var(--muted); }
.msg.typing i { display: inline-block; width: 5px; height: 5px; border-radius: 50%; background: var(--muted); margin-right: 3px; animation: blink 1.2s infinite; }
.msg.typing i:nth-child(2) { animation-delay: .2s; }
.msg.typing i:nth-child(3) { animation-delay: .4s; }
@keyframes blink { 0%, 60%, 100% { opacity: .25; } 30% { opacity: 1; } }
.chat-input { display: flex; gap: 8px; padding: 10px 12px; border-top: 1px solid var(--line); background: #FCFAF5; flex: 0 0 auto; }
.chat-input input { flex: 1; border: 1px solid var(--line); background: #fff; padding: 9px 12px; font-size: 13px; min-width: 0; }
.chat-input input:focus { outline: none; border-color: var(--ink); }
.chat-input button { width: 40px; height: 40px; border: 0; background: var(--ink); color: var(--paper); display: flex; align-items: center; justify-content: center; flex: 0 0 auto; }
.chat-input button svg { width: 18px; height: 18px; }

/* ---------- Toast ---------- */
.toast {
    position: fixed;
    left: 50%;
    top: 88px;
    bottom: auto;
    transform: translate(-50%, -12px);
    z-index: 140;
    background: var(--ink);
    color: var(--paper);
    font-size: 13px;
    padding: 11px 20px;
    border-radius: 999px;
    opacity: 0;
    pointer-events: none;
    transition: opacity .25s, transform .25s var(--ease);
    max-width: calc(100vw - 40px);
    text-align: center;
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 入场动画 ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.reveal.in { opacity: 1; transform: none; }
.reveal-d1 { transition-delay: .08s; }
.reveal-d2 { transition-delay: .16s; }
.reveal-d3 { transition-delay: .24s; }

/* ---------- 每周更新：栏目 + 周报 ---------- */
.weekly-feature {
    display: grid;
    grid-template-columns: 1.15fr 1fr;
    gap: 0;
    border: 1px solid var(--line);
    background: var(--paper-2);
    margin-bottom: 26px;
    transition: transform .35s var(--ease), box-shadow .35s var(--ease);
}
.weekly-feature:hover { transform: translateY(-2px); box-shadow: var(--shadow-1); }
.wf-media { position: relative; min-height: 320px; overflow: hidden; background: var(--paper-3); }
.wf-media img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.wf-body { padding: clamp(24px, 3.4vw, 44px); display: flex; flex-direction: column; justify-content: center; }
.wf-kicker { font-family: var(--mono); font-size: 11px; letter-spacing: .2em; text-transform: uppercase; color: var(--accent); margin: 0 0 14px; }
.wf-body h3 { margin: 0 0 14px; font-size: clamp(22px, 2.4vw, 32px); line-height: 1.35; font-weight: 700; }
.wf-sum { margin: 0 0 20px; color: var(--muted); font-size: 14px; line-height: 1.85; }
.wf-meta { margin: 0; font-family: var(--mono); font-size: 12px; color: var(--muted-2); display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.wf-go { display: inline-flex; align-items: center; gap: 6px; color: var(--ink); }
.wf-go svg { width: 15px; height: 15px; }

.channel-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.channel-card { border: 1px solid var(--line); background: #FBF8F2; display: flex; flex-direction: column; transition: transform .35s var(--ease), border-color .35s var(--ease); }
.channel-card:hover { transform: translateY(-3px); border-color: var(--ink); }
.ch-cover { position: relative; aspect-ratio: 16/10; overflow: hidden; background: var(--paper-3); }
.ch-cover img { width: 100%; height: 100%; object-fit: cover; transition: transform .6s var(--ease); }
.channel-card:hover .ch-cover img { transform: scale(1.04); }
.ch-ph { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; font-family: var(--mono); font-size: 11px; letter-spacing: .2em; color: var(--muted-2); }
.ch-badge { position: absolute; left: 12px; top: 12px; padding: 4px 10px; background: rgba(23,19,15,.78); color: var(--paper); font-family: var(--mono); font-size: 10.5px; letter-spacing: .08em; }
.ch-body { padding: 20px 20px 22px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.ch-body b { font-size: 18px; line-height: 1.4; }
.ch-body p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.75; }
.ch-count { margin-top: auto; padding-top: 10px; font-family: var(--mono); font-size: 11.5px; color: var(--muted-2); display: inline-flex; align-items: center; gap: 5px; }
.ch-count svg { width: 13px; height: 13px; }

.report-list { margin-top: 30px; border-top: 1px solid var(--line); padding-top: 18px; }
.report-row { display: flex; align-items: baseline; gap: 18px; padding: 14px 4px; border-bottom: 1px solid var(--line-soft); transition: padding-left .3s var(--ease), color .3s var(--ease); }
.report-row:hover { padding-left: 12px; color: var(--accent); }
.rr-week { flex: 0 0 auto; font-family: var(--mono); font-size: 11.5px; color: var(--muted-2); min-width: 150px; }
.report-row b { font-size: 15px; font-weight: 600; line-height: 1.6; }
.rr-go { margin-left: auto; display: inline-flex; }
.rr-go svg { width: 14px; height: 14px; }

/* ---------- 周报详情 ---------- */
.report-view, .channel-view { padding: 118px 0 90px; }
.rv-wrap { max-width: 820px; }
.rv-back { display: inline-flex; margin-bottom: 30px; font-family: var(--mono); font-size: 12px; color: var(--muted); }
.rv-back:hover { color: var(--accent); }
.rv-kicker { font-family: var(--mono); font-size: 11px; letter-spacing: .2em; text-transform: uppercase; color: var(--accent); margin: 0 0 16px; }
.rv-title { margin: 0 0 14px; font-size: clamp(26px, 3.6vw, 40px); line-height: 1.3; font-weight: 700; letter-spacing: -.01em; }
.rv-meta { margin: 0 0 26px; font-family: var(--mono); font-size: 12px; color: var(--muted-2); }
.rv-cover { margin: 0 0 26px; }
.rv-cover img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
.rv-sum { margin: 0 0 30px; padding-left: 16px; border-left: 2px solid var(--accent); color: var(--ink-2); font-size: 15px; line-height: 1.9; }
.rp-body { margin-top: 8px; }
.rp-p { margin: 0 0 20px; font-size: 15.5px; line-height: 2; color: var(--ink-2); }
.rp-h2 { margin: 40px 0 16px; font-size: 21px; line-height: 1.5; padding-left: 12px; border-left: 3px solid var(--accent); }
.rp-quote { margin: 0 0 22px; padding: 16px 18px; background: var(--paper-2); color: var(--muted); font-size: 15px; line-height: 1.9; border: 0; }
.rp-ul { margin: 0 0 22px; padding-left: 20px; }
.rp-ul li { margin: 6px 0; font-size: 15.5px; line-height: 1.95; color: var(--ink-2); }
.rp-fig { margin: 0 0 18px; }
.rp-fig img { width: 100%; }
.rp-fig figcaption { margin-top: 8px; text-align: center; font-size: 12px; color: var(--muted-2); }
.rp-video { margin: 0 0 22px; }
.rp-video video { width: 100%; background: #000; }
.rp-video figcaption { margin-top: 8px; text-align: center; font-size: 12px; color: var(--muted-2); }
.rp-video-ph {
    margin: 0 0 22px;
    padding: 34px 20px;
    border: 1px dashed var(--line);
    background: var(--paper-2);
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}
.rp-video-ph span { font-family: var(--mono); font-size: 10.5px; letter-spacing: .24em; color: var(--muted-2); }
.rp-video-ph b { font-size: 16px; line-height: 1.6; }
.rp-video-ph i { font-style: normal; font-size: 12.5px; color: var(--muted); }
.rv-nav { display: flex; justify-content: space-between; gap: 20px; margin-top: 48px; padding-top: 22px; border-top: 1px solid var(--line); }
.rv-nav a { display: flex; flex-direction: column; gap: 6px; max-width: 45%; }
.rv-nav a.is-next { text-align: right; margin-left: auto; }
.rv-nav a span { font-family: var(--mono); font-size: 11px; color: var(--muted-2); }
.rv-nav a b { font-size: 14px; font-weight: 600; line-height: 1.6; }
.rv-nav a:hover b { color: var(--accent); }
.rv-cta { margin-top: 44px; padding: 26px; background: var(--paper-2); border: 1px solid var(--line); display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap; }
.rv-cta b { font-size: 16px; }
.rv-cta p { margin: 6px 0 0; color: var(--muted); font-size: 13px; }

/* ---------- 栏目详情 ---------- */
.chv-head { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; align-items: center; margin-bottom: 40px; }
.chv-cover { aspect-ratio: 16/10; overflow: hidden; background: var(--paper-3); }
.chv-cover img { width: 100%; height: 100%; object-fit: cover; }
.chv-copy .rv-title { font-size: clamp(26px, 3.2vw, 36px); }
.chv-stat { margin: 18px 0 0; font-family: var(--mono); font-size: 12px; color: var(--muted-2); }
.chv-grid { columns: 3; column-gap: 14px; }
.chv-grid .gal-item { margin-bottom: 14px; }
.chv-videos { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.chv-video { border: 1px solid var(--line); background: #FBF8F2; padding: 0; text-align: left; display: flex; flex-direction: column; }
.chv-video img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
.chv-video .gal-video-ph { aspect-ratio: 16/9; }
.chv-video-name { padding: 10px 12px 12px; font-size: 13px; line-height: 1.6; }

/* ---------- 状态页面 ---------- */
.state-block { padding: clamp(70px, 12vw, 140px) 0; text-align: center; }
.state-block b { display: block; font-size: 20px; margin-bottom: 10px; }
.state-block p { margin: 0 0 22px; color: var(--muted); font-size: 13.5px; }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1080px) {
    .nav { gap: 22px; }
    .dims { grid-template-columns: repeat(3, 1fr); }
    .dim:nth-child(3n) { border-right: 0; }
    .dim { border-bottom: 1px solid var(--line); min-height: 190px; }
    .dim:nth-last-child(-n+2) { border-bottom: 0; }
    .course-card { grid-column: span 6; }
    .course-card.is-featured { grid-template-columns: 1fr; }
    .course-card.is-featured .cc-media { min-height: 320px; aspect-ratio: 16/9; }
    .course-card.is-featured .cc-body { padding: 30px; }
    .video-grid { grid-template-columns: repeat(2, 1fr); }
    .detail-body { grid-template-columns: 1fr; }
    .detail-aside { position: static; }
    .gallery { columns: 2; }
    .weekly-feature { grid-template-columns: 1fr; }
    .wf-media { min-height: 260px; }
    .channel-grid { grid-template-columns: repeat(2, 1fr); }
    .chv-head { grid-template-columns: 1fr; }
    .chv-grid { columns: 2; }
    .chv-videos { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 860px) {
    .nav { display: none; }
    .topbar { height: 62px; }
    .topbar.solid { height: 58px; }
    .brand-mark { width: 26px; height: 26px; }
    .brand-text b { font-size: 14px; }
    .brand-text i { font-size: 9.5px; letter-spacing: .18em; }
    .top-actions .ghost-link { display: none; }
    .top-actions .ghost-link.is-user { display: inline-flex; padding: 6px 11px; font-size: 11.5px; }
    .top-actions #btnMy { display: none !important; }
    .top-actions #btnJoinTop2 { display: none !important; }
    .brand-text i { display: none; }
    .brand-text b { font-size: 14px; }
    .top-actions .btn { height: 38px; padding: 0 16px; font-size: 12.5px; }
    .hero { min-height: 92svh; }
    .hero-title { font-size: clamp(36px, 10.4vw, 56px); }
    .hero-sub { font-size: 13.5px; margin-top: 20px; }
    .hero-side { display: none; }
    .hero-stats { gap: 22px; margin-top: 34px; }
    .hero-stat b { font-size: 22px; }
    .hero-stat span { font-size: 10px; letter-spacing: .1em; }
    .section-head { flex-direction: column; align-items: flex-start; gap: 20px; }
    .section-head-right { align-items: flex-start; width: 100%; }
    .section-head > .section-index { order: 2; }
    .section-head-right .section-index { order: 0; }
    .dims { grid-template-columns: repeat(2, 1fr); }
    .dim:nth-child(3n) { border-right: 1px solid var(--line); }
    .dim:nth-child(2n) { border-right: 0; }
    .dim { min-height: 168px; padding: 22px 16px; }
    .dim:nth-last-child(-n+2) { border-bottom: 1px solid var(--line); }
    .dim:last-child { border-bottom: 0; }
    .dim-name { font-size: 22px; }
    .dim-desc { margin-top: 12px; font-size: 12px; }
    .course-card, .course-card.is-featured, .course-cta, .course-cta.span8 { grid-column: span 12; }
    .course-cta { min-height: 0; }
    .course-card.is-featured .cc-media { min-height: 0; aspect-ratio: 4/3; }
    .gallery { columns: 2; column-gap: 10px; }
    .gal-item { margin-bottom: 10px; }
    .video-grid { grid-template-columns: 1fr; }
    .about-grid { grid-template-columns: 1fr; gap: 34px; }
    .about-statement { font-size: 23px; }
    .footer-inner { flex-direction: column; }
    .footer-legal { text-align: left; }
    .sheet { padding: 0; align-items: flex-end; }
    .sheet-card { grid-template-columns: 1fr; max-height: 94svh; width: 100%; }
    .sheet-copy { padding: 26px 22px; }
    .sheet-copy h2 { font-size: 24px; }
    .join-points { display: none; }
    .sheet-form { padding: 24px 22px calc(26px + env(safe-area-inset-bottom)); }
    .chat-dock { right: 12px; bottom: calc(12px + env(safe-area-inset-bottom)); }
    .chat-fab { height: 46px; padding: 0 16px 0 10px; }
    .chat-fab-text { font-size: 12.5px; }
    .chat-panel {
        position: fixed;
        left: 0; right: 0; bottom: 0;
        width: 100%;
        max-width: none;
        height: 82svh;
        border-left: 0; border-right: 0; border-bottom: 0;
        padding-bottom: env(safe-area-inset-bottom);
    }
    .lb-prev, .lb-next { width: 38px; height: 38px; }
    .lb-prev { left: 8px; }
    .lb-next { right: 8px; }
    .detail-hero { min-height: 78svh; }
    .detail-hero .hero-inner { padding-top: 100px; }
    .outcome-grid { grid-template-columns: 1fr; }
    .detail-body { gap: 32px; }
    .prose p { font-size: 14.5px; line-height: 1.9; }
}

@media (max-width: 430px) {
    body { font-size: 15px; }
    .wrap { padding-inline: 18px; }
    .hero-inner { padding-inline: 18px; }
    .hero-title { font-size: clamp(34px, 11vw, 46px); }
    .hero-meta { flex-direction: column; align-items: stretch; }
    .hero-meta .btn { width: 100%; }
    .dims { grid-template-columns: 1fr; }
    .dim { border-right: 0; min-height: 0; padding: 20px 0; }
    .dim:last-child { border-bottom: 0; }
    .dim-name { margin-top: 8px; font-size: 23px; }
    .dim-desc { margin-top: 8px; }
    .dim-count { margin-top: 10px; }
    .gallery { columns: 2; }
    .section { padding: 62px 0; }
    .section-head h2 { font-size: 29px; }
    .cc-body { padding: 18px; }
    .cc-title { font-size: 21px; }
    .field-row { grid-template-columns: 1fr; gap: 0; }
    .chat-fab-text { display: none; }
    .chat-fab { width: 48px; padding: 0; justify-content: center; }
    .chat-fab-dot { position: absolute; top: 10px; right: 10px; }
    .video-empty { flex-direction: column; align-items: flex-start; }
    .stamp { display: none; }
    .footer-links { flex-wrap: wrap; }
    .channel-grid { grid-template-columns: 1fr; }
    .wf-media { min-height: 210px; }
    .report-row { flex-wrap: wrap; gap: 4px 12px; }
    .rr-week { min-width: 0; }
    .chv-grid { columns: 2; }
    .chv-videos { grid-template-columns: 1fr; }
    .report-view, .channel-view { padding: 92px 0 60px; }
    .rv-nav { flex-direction: column; }
    .rv-nav a, .rv-nav a.is-next { max-width: 100%; text-align: left; margin-left: 0; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
    .reveal { opacity: 1; transform: none; }
}