/* ============================================================
   活力酷（库） · 设计系统
   设计语言参考 Apple：流体动效、半透明材质、光学排版、克制配色
   ============================================================ */

/* ---------- 设计变量 ---------- */
:root {
  color-scheme: light;
  --bg: #f5f5f7;
  --surface: #ffffff;
  --surface-2: #f0f0f3;
  --text: #1d1d1f;
  --text-2: #6e6e73;
  --text-3: #8e8e93;
  --hairline: rgba(0, 0, 0, 0.08);
  --accent: #0071e3;

  /* 难度色 */
  --lv0: #248a3d;  /* 入门 · 绿 */
  --lv1: #0a84ff;  /* 基础 · 蓝 */
  --lv2: #c93400;  /* 进阶 · 橙 */

  /* Apple 流体曲线：cubic-bezier 近似的弹簧感 */
  --ease-spring: cubic-bezier(0.32, 0.72, 0, 1);
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);

  --radius-lg: 24px;
  --radius-md: 20px;
  --radius-sm: 14px;

  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.04), 0 8px 24px rgba(0, 0, 0, 0.05);
  --shadow-lift: 0 2px 4px rgba(0, 0, 0, 0.05), 0 20px 48px rgba(0, 0, 0, 0.1);
  --shadow-sheet: 0 24px 80px rgba(0, 0, 0, 0.28);

  --nav-h: 60px;
}

/* ---------- 暗黑主题 ---------- */
[data-theme="dark"] {
  color-scheme: dark;
  --bg: #000000;
  --surface: #1c1c1e;
  --surface-2: #2c2c2e;
  --text: #f5f5f7;
  --text-2: #a1a1a6;
  --text-3: #6e6e73;
  --hairline: rgba(255, 255, 255, 0.12);
  --accent: #0a84ff;

  --lv0: #30d158;
  --lv1: #0a84ff;
  --lv2: #ff9f0a;

  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.42);
  --shadow-lift: 0 2px 4px rgba(0, 0, 0, 0.45), 0 20px 48px rgba(0, 0, 0, 0.55);
}

[data-theme="dark"] .nav { background: rgba(22, 22, 24, 0.72); }
[data-theme="dark"] .nav-badge { background: rgba(10, 132, 255, 0.18); }
[data-theme="dark"] .home-eyebrow { box-shadow: 0 1px 4px rgba(0, 0, 0, 0.4); }
[data-theme="dark"] .home::before {
  background: radial-gradient(circle, rgba(10, 132, 255, 0.22), transparent 65%);
}
[data-theme="dark"] .home::after {
  background: radial-gradient(circle, rgba(48, 209, 88, 0.17), transparent 65%);
}
[data-theme="dark"] .hcard-head:hover { background: rgba(255, 255, 255, 0.05); }
[data-theme="dark"] .hsub:hover { background: rgba(255, 255, 255, 0.06); }
[data-theme="dark"] .back-btn:hover { background: rgba(10, 132, 255, 0.15); }
[data-theme="dark"] .thumb-badge { background: rgba(20, 20, 22, 0.75); }
[data-theme="dark"] .chip.lv-0 { background: rgba(48, 209, 88, 0.16); }
[data-theme="dark"] .chip.lv-1 { background: rgba(10, 132, 255, 0.18); }
[data-theme="dark"] .chip.lv-2 { background: rgba(255, 159, 10, 0.16); }
[data-theme="dark"] .points-list li::before { background: rgba(10, 132, 255, 0.2); }
[data-theme="dark"] .play-media { box-shadow: 0 24px 64px rgba(0, 0, 0, 0.6); }
[data-theme="dark"] .theme-toggle { box-shadow: 0 1px 4px rgba(0, 0, 0, 0.4); }

/* 主题切换过渡：全元素短暂缓动，避免亮度突变 */
.theme-anim, .theme-anim *, .theme-anim *::before, .theme-anim *::after {
  transition: background-color 0.38s ease, border-color 0.38s ease,
    color 0.38s ease, box-shadow 0.38s ease, fill 0.38s ease !important;
}

/* ---------- 基础 ---------- */
*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

::selection { background: rgba(10, 132, 255, 0.18); }

a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; padding: 0; }
h1, h2, h3, h4, p { margin: 0; }
ol, ul { margin: 0; padding: 0; list-style: none; }

.container { max-width: 1080px; margin-inline: auto; padding-inline: 24px; }

.ic { width: 1.25em; height: 1.25em; flex: none; display: inline-block; vertical-align: -0.28em; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

/* ---------- 顶部导航：半透明浮动材质 ---------- */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: var(--nav-h);
  background: rgba(245, 245, 247, 0.72);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid transparent;
  transition: border-color 0.35s ease, background 0.35s ease, transform 0.5s var(--ease-spring);
}
.nav.scrolled { border-bottom-color: var(--hairline); }

.nav-inner { height: var(--nav-h); display: flex; align-items: center; justify-content: space-between; }

.brand { display: inline-flex; align-items: center; gap: 10px; }
.brand:active { opacity: 0.7; }
.brand-mark {
  width: 30px; height: 30px; border-radius: 9px;
  background: linear-gradient(135deg, #0a84ff, #30d158);
  display: grid; place-items: center;
  box-shadow: 0 4px 12px rgba(10, 132, 255, 0.35);
}
.brand-mark svg { width: 15px; height: 15px; }
.brand-name { font-size: 17px; font-weight: 600; letter-spacing: -0.01em; }

.nav-side { display: flex; align-items: center; gap: 12px; }
.nav-crumb { font-size: 13px; color: var(--text-3); letter-spacing: 0.01em; }
.nav-badge {
  font-size: 12px; font-weight: 600; letter-spacing: 0.02em;
  color: var(--accent);
  background: rgba(0, 113, 227, 0.1);
  padding: 4px 10px; border-radius: 999px;
}

/* 版本更新按钮：品牌渐变 + 呼吸光晕提示 */
.update-btn {
  padding: 6px 14px; border: none; border-radius: 999px;
  background: linear-gradient(135deg, #0A84FF, #30D158);
  color: #fff; font-size: 12px; font-weight: 600; letter-spacing: 0.03em;
  cursor: pointer;
  animation: updatePulse 2s ease-in-out infinite;
}
.update-btn:hover { filter: brightness(1.12); }
.update-btn[hidden] { display: none; }

/* 导航栏版本号 */
.nav-ver {
  font-size: 11px; color: var(--text-3); letter-spacing: 0.04em;
  font-variant-numeric: tabular-nums;
}
@keyframes updatePulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(10, 132, 255, 0.45); }
  50% { box-shadow: 0 0 0 7px rgba(10, 132, 255, 0); }
}

.theme-toggle {
  width: 34px; height: 34px; border-radius: 50%;
  display: grid; place-items: center;
  background: var(--surface);
  border: 1px solid var(--hairline);
  color: var(--text-2);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.05);
  transition: transform 0.15s ease, color 0.25s ease, border-color 0.25s ease;
}
.theme-toggle:hover { color: var(--text); }
.theme-toggle:active { transform: scale(0.9); }
.theme-toggle .ic { width: 16px; height: 16px; }
.theme-toggle .ic-sun { display: none; }
[data-theme="dark"] .theme-toggle .ic-sun { display: inline-block; }
[data-theme="dark"] .theme-toggle .ic-moon { display: none; }

/* ---------- 视图切换动效（iOS 式推入 / 返回） ---------- */
.app { min-height: 60vh; transition: transform 0.5s var(--ease-spring); }

.view-enter-fwd { animation: viewFwd 0.55s var(--ease-spring) both; }
.view-enter-back { animation: viewBack 0.55s var(--ease-spring) both; }

@keyframes viewFwd {
  from { opacity: 0; transform: translateX(48px); }
  to { opacity: 1; transform: translateX(0); }
}
@keyframes viewBack {
  from { opacity: 0; transform: translateX(-48px); }
  to { opacity: 1; transform: translateX(0); }
}

/* 列表逐项浮现 */
[data-stagger] > * {
  animation: rise 0.7s var(--ease-out) both;
  animation-delay: calc(var(--i, 0) * 65ms);
}
@keyframes rise {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- 首页（单屏课程仪表盘，无滚动） ---------- */
.home {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: calc(var(--nav-h) + 12px);
  padding-bottom: 32px;
  overflow: hidden;
}
.home::before, .home::after {
  content: ""; position: absolute; border-radius: 50%;
  filter: blur(90px); pointer-events: none; z-index: -1;
}
.home::before {
  width: 460px; height: 460px; top: -140px; left: 6%;
  background: radial-gradient(circle, rgba(10, 132, 255, 0.15), transparent 65%);
}
.home::after {
  width: 400px; height: 400px; bottom: -120px; right: 5%;
  background: radial-gradient(circle, rgba(48, 209, 88, 0.13), transparent 65%);
}

.home-head { margin-bottom: 30px; }
.home-eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 12.5px; font-weight: 500; color: var(--text-2); letter-spacing: 0.02em;
  background: var(--surface);
  border: 1px solid var(--hairline);
  padding: 6px 13px; border-radius: 999px;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.04);
}
.home-eyebrow .dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: linear-gradient(135deg, #0a84ff, #30d158);
}
.home-head h1 {
  margin-top: 16px;
  font-size: clamp(1.75rem, 3.2vw, 2.3rem);
  font-weight: 700; letter-spacing: -0.026em;
}
.home-sub { margin-top: 8px; font-size: 14px; color: var(--text-2); }

.home-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }

/* 单屏页（首页 / 播放页）：隐藏页脚；桌面足够高时锁定滚动 */
body.home-view .footer,
body.play-view .footer { display: none; }
@media (min-width: 961px) and (min-height: 730px) {
  body.home-view { overflow: hidden; }
}
@media (min-width: 961px) and (min-height: 780px) {
  body.play-view { overflow: hidden; }
}

/* ---------- 通用卡片 ---------- */
.card {
  position: relative;
  display: block;
  background: var(--surface);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  transition: transform 0.5s var(--ease-spring), box-shadow 0.5s var(--ease-spring);
  will-change: transform;
}
.card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lift); }
.card:active { transform: scale(0.98); transition-duration: 0.12s; }

/* ---------- 渐变图标块（首页 / 板块页共用） ---------- */
.cat-icon {
  position: relative;
  width: 54px; height: 54px; border-radius: 16px;
  background: linear-gradient(135deg, var(--c1), var(--c2));
  color: #fff;
  display: grid; place-items: center;
  box-shadow: 0 10px 22px color-mix(in srgb, var(--c1) 38%, transparent);
}
.cat-icon .ic { width: 27px; height: 27px; }

/* ---------- 首页课程卡片（仪表盘式，直达板块） ---------- */
.hcard { padding: 20px; }

.hcard-head {
  display: flex; align-items: center; gap: 13px;
  margin: -6px -6px 0; padding: 6px;
  border-radius: 14px;
  transition: background 0.25s ease;
}
.hcard-head:hover { background: rgba(0, 0, 0, 0.03); }
.hcard-head .cat-icon { width: 46px; height: 46px; border-radius: 13px; flex: none; }
.hcard-head .cat-icon .ic { width: 23px; height: 23px; }
.hcard-title { flex: 1; min-width: 0; }
.hcard-title .en {
  display: block;
  font-size: 10.5px; font-weight: 700; letter-spacing: 0.13em;
  color: var(--text-3);
}
.hcard-title h3 { margin-top: 2px; font-size: 18.5px; font-weight: 700; letter-spacing: -0.018em; }
.hcard-total {
  font-size: 12px; color: var(--text-3);
  font-variant-numeric: tabular-nums; white-space: nowrap;
}

.hcard-subs {
  margin-top: 14px; padding-top: 8px;
  border-top: 1px solid var(--hairline);
  display: flex; flex-direction: column;
}
.hsub {
  display: flex; align-items: center; gap: 11px;
  padding: 7.5px 9px; border-radius: 12px;
  transition: background 0.25s ease, transform 0.15s ease;
}
.hsub:hover { background: rgba(0, 0, 0, 0.035); }
.hsub:active { transform: scale(0.98); }
.hsub-icon {
  width: 30px; height: 30px; border-radius: 9px; flex: none;
  background: linear-gradient(135deg, var(--c1), var(--c2));
  color: #fff;
  display: grid; place-items: center;
}
.hsub-icon .ic { width: 15px; height: 15px; }
.hsub-name { flex: 1; font-size: 14px; font-weight: 550; letter-spacing: -0.01em; }
.hsub-count { font-size: 12px; color: var(--text-3); font-variant-numeric: tabular-nums; }
.hsub > .chev {
  width: 14px; height: 14px; color: var(--text-3);
  opacity: 0; transform: translateX(-4px);
  transition: opacity 0.3s ease, transform 0.35s var(--ease-spring);
}
.hsub:hover > .chev { opacity: 1; transform: translateX(0); }

/* ---------- 内页头部 ---------- */
.page-head { padding-top: calc(var(--nav-h) + 44px); }

.back-btn {
  display: inline-flex; align-items: center; gap: 3px;
  font-size: 14.5px; font-weight: 500; color: var(--accent);
  padding: 8px 16px 8px 10px; margin-left: -10px;
  border-radius: 999px;
  transition: background 0.25s ease, transform 0.15s ease;
}
.back-btn:hover { background: rgba(0, 113, 227, 0.08); }
.back-btn:active { transform: scale(0.96); }

.page-eyebrow {
  margin-top: 26px;
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 12px; font-weight: 700; letter-spacing: 0.12em;
  color: var(--c1, var(--text-3));
}
.page-eyebrow::before {
  content: ""; width: 18px; height: 3px; border-radius: 2px;
  background: linear-gradient(90deg, var(--c1), var(--c2));
}

.page-head h1 {
  margin-top: 10px;
  font-size: clamp(2rem, 4.4vw, 2.9rem);
  font-weight: 700; letter-spacing: -0.028em; line-height: 1.12;
}
.page-desc { margin-top: 14px; max-width: 660px; font-size: 15.5px; line-height: 1.7; color: var(--text-2); }

.page-meta { margin-top: 20px; display: flex; flex-wrap: wrap; gap: 10px; }
.meta-chip {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13px; color: var(--text-2);
  background: var(--surface); border: 1px solid var(--hairline);
  padding: 7px 13px; border-radius: 999px;
  font-variant-numeric: tabular-nums;
}
.meta-chip .ic { width: 15px; height: 15px; color: var(--text-3); }

/* ---------- 板块卡片（二级） ---------- */
.sub-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; padding: 36px 0 8px; }

.sub-card { display: flex; align-items: center; gap: 18px; padding: 20px; border-radius: var(--radius-md); }

.sub-thumb {
  position: relative; flex: none;
  width: 96px; height: 96px; border-radius: 16px;
  background: linear-gradient(135deg, var(--c1), var(--c2));
  color: rgba(255, 255, 255, 0.95);
  display: grid; place-items: center;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.25), 0 8px 18px color-mix(in srgb, var(--c1) 30%, transparent);
}
.sub-thumb .ic { width: 38px; height: 38px; }

.sub-body { flex: 1; min-width: 0; }
.sub-body h3 { font-size: 17.5px; font-weight: 650; letter-spacing: -0.015em; }
.sub-body .desc {
  margin-top: 5px; font-size: 13.5px; line-height: 1.55; color: var(--text-2);
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}
.sub-meta { margin-top: 9px; display: flex; align-items: center; gap: 12px; font-size: 12.5px; color: var(--text-3); }
.sub-meta .ic { width: 14px; height: 14px; margin-right: 3px; }

.sub-card > .chev { color: var(--text-3); flex: none; transition: transform 0.4s var(--ease-spring), color 0.3s; }
.sub-card:hover > .chev { transform: translateX(4px); color: var(--accent); }

/* ---------- 视频卡片（三级） ---------- */
.video-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; padding: 36px 0 8px; }

.video-card { overflow: hidden; cursor: pointer; border-radius: var(--radius-md); }

.video-thumb {
  position: relative; aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--c1), var(--c2));
  overflow: hidden;
}
/* 视频封面（七牛抽帧图）：铺满缩略图，加载失败由 onerror 移除自动回退渐变 */
.thumb-cover, .rel-cover {
  position: absolute; inset: 0; width: 100%; height: 100%;
  object-fit: cover;
}
.video-thumb:has(.thumb-cover)::before {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(0,0,0,.08), rgba(0,0,0,.30));
}
.video-thumb:has(.thumb-cover) .thumb-watermark { display: none; }
.rel-thumb:has(.rel-cover) > .ic { display: none; }
.video-thumb::after { /* 顶部受光边缘，模拟材质 */
  content: ""; position: absolute; inset: 0;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.22);
}
.thumb-watermark {
  position: absolute; right: -14px; bottom: -20px;
  width: 108px; height: 108px;
  color: rgba(255, 255, 255, 0.2);
  transform: rotate(-10deg);
}
.thumb-play {
  position: absolute; left: 50%; top: 50%;
  width: 54px; height: 54px; border-radius: 50%;
  transform: translate(-50%, -50%) scale(0.82);
  background: rgba(255, 255, 255, 0.94);
  color: #1d1d1f;
  display: grid; place-items: center;
  opacity: 0;
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.25);
  transition: opacity 0.35s ease, transform 0.45s var(--ease-spring);
}
.thumb-play .ic { width: 22px; height: 22px; margin-left: 2px; }
.video-card:hover .thumb-play { opacity: 1; transform: translate(-50%, -50%) scale(1); }
@media (hover: none) { .thumb-play { opacity: 0.92; transform: translate(-50%, -50%) scale(1); } }

.thumb-badge {
  position: absolute; top: 10px; left: 10px;
  font-size: 11.5px; font-weight: 600; letter-spacing: 0.02em;
  padding: 4px 10px; border-radius: 999px;
  background: rgba(255, 255, 255, 0.92);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
}
.thumb-badge.lv-0 { color: var(--lv0); }
.thumb-badge.lv-1 { color: var(--lv1); }
.thumb-badge.lv-2 { color: var(--lv2); }

.thumb-duration {
  position: absolute; right: 10px; bottom: 10px;
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 12px; font-weight: 500; color: #fff;
  background: rgba(0, 0, 0, 0.55);
  -webkit-backdrop-filter: blur(8px); backdrop-filter: blur(8px);
  padding: 3px 8px; border-radius: 8px;
  font-variant-numeric: tabular-nums;
}
.thumb-duration .ic { width: 12px; height: 12px; }

.video-body { padding: 16px 18px 18px; }
.video-body h3 { font-size: 16px; font-weight: 650; letter-spacing: -0.012em; }
.video-body .desc {
  margin-top: 6px; font-size: 13px; line-height: 1.55; color: var(--text-2);
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
  min-height: calc(13px * 1.55 * 2);
}
.video-meta {
  margin-top: 12px; padding-top: 12px;
  border-top: 1px solid var(--hairline);
  display: flex; align-items: center; gap: 14px;
  font-size: 12.5px; color: var(--text-3);
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.video-meta .ic { width: 14px; height: 14px; margin-right: 4px; }

/* ---------- 页脚 ---------- */
.footer { margin-top: 104px; border-top: 1px solid var(--hairline); transition: transform 0.5s var(--ease-spring); }
.footer-inner {
  padding: 30px 24px 44px;
  display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap;
  font-size: 13px; color: var(--text-3);
}

/* ---------- 播放页（独立路由，单屏无滚动） ---------- */
.play-page {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: calc(var(--nav-h) + 14px);
  padding-bottom: 24px;
}

.play-grid {
  margin-top: 20px;
  display: grid;
  grid-template-columns: 7fr 5fr;
  gap: 30px;
  align-items: start;
}

.play-media {
  position: relative;
  aspect-ratio: 16 / 9;
  background: #000;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.28);
}
.play-media video { width: 100%; height: 100%; display: block; }

/* 受保护播放：授权验证中 / 失败遮罩 */
.play-loading {
  position: absolute; inset: 0; z-index: 2;
  display: flex; align-items: center; justify-content: center; gap: 10px;
  background: rgba(10, 10, 12, 0.92); color: rgba(255, 255, 255, 0.85);
  font-size: 14px; border-radius: inherit; text-align: center; padding: 24px;
}
.play-loading.error { color: #ff9f0a; }
.browser-play-login { display: flex; flex-direction: column; gap: 10px; width: min(300px, 100%); }
.browser-play-login strong { font-size: 17px; color: #fff; }
.browser-play-login input { width: 100%; padding: 10px 12px; border: 1px solid #777; border-radius: 8px; background: #fff; color: #1d1d1f; }
.browser-play-login button { padding: 10px 12px; border: 0; border-radius: 8px; background: #0a84ff; color: #fff; cursor: pointer; }
.browser-play-login button:disabled { opacity: .6; cursor: wait; }
.browser-play-message { min-height: 1em; color: #ff9f0a; }
.play-loading .spinner {
  width: 18px; height: 18px; border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.25); border-top-color: #fff;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.play-info .page-eyebrow { margin-top: 2px; }
.play-info h1 {
  margin-top: 8px;
  font-size: clamp(1.45rem, 2.4vw, 1.85rem);
  font-weight: 700; letter-spacing: -0.022em; line-height: 1.2;
}

.chips-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.chip {
  display: inline-flex; align-items: center; gap: 5px;
  font-size: 12.5px; font-weight: 500;
  background: var(--surface-2); color: var(--text-2);
  padding: 6px 12px; border-radius: 999px;
  font-variant-numeric: tabular-nums;
}
.chip .ic { width: 14px; height: 14px; }
.chip.lv-0 { color: var(--lv0); background: color-mix(in srgb, var(--lv0) 10%, #fff); }
.chip.lv-1 { color: var(--lv1); background: color-mix(in srgb, var(--lv1) 10%, #fff); }
.chip.lv-2 { color: var(--lv2); background: color-mix(in srgb, var(--lv2) 10%, #fff); }

.play-desc { margin-top: 12px; font-size: 14px; line-height: 1.65; color: var(--text-2); }

.play-section { margin-top: 18px; }
.play-section h3 {
  display: flex; align-items: center; gap: 8px;
  font-size: 14px; font-weight: 650; letter-spacing: -0.01em;
}
.play-section h3 .ic { width: 16px; height: 16px; color: var(--accent); }

.points-list { margin-top: 12px; display: grid; gap: 9px; counter-reset: pt; }
.points-list li {
  position: relative; padding-left: 34px;
  font-size: 13.5px; line-height: 1.55; color: var(--text);
  counter-increment: pt;
}
.points-list li::before {
  content: counter(pt);
  position: absolute; left: 0; top: 0;
  width: 22px; height: 22px; border-radius: 50%;
  background: rgba(0, 113, 227, 0.1); color: var(--accent);
  font-size: 12px; font-weight: 650;
  display: grid; place-items: center;
  font-variant-numeric: tabular-nums;
}

.dose-card {
  margin-top: 16px;
  display: flex; align-items: center; gap: 12px;
  background: var(--surface-2); border-radius: var(--radius-sm);
  padding: 12px 16px;
  font-size: 13.5px; font-weight: 500;
}
.dose-card .ic { width: 17px; height: 17px; color: var(--accent); flex: none; }

.play-related { margin-top: 26px; }
.play-related .play-section { margin-top: 0; }
.rel-row { margin-top: 12px; display: flex; gap: 12px; }

.rel-card {
  flex: none; width: 190px;
  border-radius: var(--radius-sm); overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--hairline);
  box-shadow: var(--shadow-card);
  transition: transform 0.4s var(--ease-spring), box-shadow 0.4s var(--ease-spring);
}
.rel-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-lift); }
.rel-card:active { transform: scale(0.97); transition-duration: 0.1s; }
.rel-thumb {
  position: relative; aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, var(--c1), var(--c2));
  display: grid; place-items: center;
  color: rgba(255, 255, 255, 0.9);
}
.rel-thumb .ic { width: 26px; height: 26px; }
.rel-thumb .dur {
  position: absolute; right: 6px; bottom: 6px;
  font-size: 10.5px; font-weight: 500; color: #fff;
  background: rgba(0, 0, 0, 0.55); padding: 2px 6px; border-radius: 6px;
  font-variant-numeric: tabular-nums;
}
.rel-card p {
  padding: 9px 11px 11px;
  font-size: 12.5px; font-weight: 550; line-height: 1.4;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .home { justify-content: flex-start; padding-top: calc(var(--nav-h) + 30px); }
  .home-grid { grid-template-columns: 1fr; }
  .hcard-subs { display: grid; grid-template-columns: 1fr 1fr; gap: 0 6px; }
  .hsub-count, .hsub > .chev { display: none; }
  .sub-grid { grid-template-columns: 1fr; }
  .video-grid { grid-template-columns: repeat(2, 1fr); }
  .play-page { justify-content: flex-start; padding-top: calc(var(--nav-h) + 24px); }
  .play-grid { grid-template-columns: 1fr; gap: 20px; }
  .rel-row { overflow-x: auto; padding-bottom: 4px; scrollbar-width: none; }
  .rel-row::-webkit-scrollbar { display: none; }
  .rel-card { width: 172px; }
}

@media (max-width: 640px) {
  .video-grid { grid-template-columns: 1fr; }
  .nav-crumb { display: none; }
}

/* ---------- 无障碍：减弱动态效果 ---------- */
@media (prefers-reduced-motion: reduce) {
  .view-enter-fwd, .view-enter-back { animation-name: fadeOnly; }
  [data-stagger] > * { animation-name: fadeOnly; animation-delay: 0s; }
  .card, .card:hover { transform: none; transition: box-shadow 0.3s ease; }
  .card:active { transform: none; }
  .thumb-play { transition: opacity 0.2s ease; }
}
@keyframes fadeOnly { from { opacity: 0; } to { opacity: 1; } }

/* ---------- 无障碍：降低透明度 ---------- */
@media (prefers-reduced-transparency: reduce) {
  .nav { background: var(--bg); -webkit-backdrop-filter: none; backdrop-filter: none; }
  .scrim { -webkit-backdrop-filter: none; backdrop-filter: none; }
  .thumb-badge, .thumb-duration { -webkit-backdrop-filter: none; backdrop-filter: none; }
}