/* =========================================================================
   B体育旧版主站 · 共享样式 /assets/site.css
   深空蓝基底 · 荧光青主强调 · 活力橙决策点 · 暗金点缀
   ========================================================================= */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 132px;
}

body,
h1, h2, h3, h4, p, ul, ol, li, figure, blockquote {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

img, svg, video {
  display: block;
  max-width: 100%;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

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

table { border-collapse: collapse; width: 100%; }

/* ---------- 2. Design tokens ---------- */
:root {
  --bg: #0A1A2F;
  --bg-2: #0E2138;
  --card: #132B45;
  --line: #1E3E5C;

  --cyan: #00E5C7;
  --cyan-soft: #7DF3E3;
  --orange: #FF6B35;
  --orange-soft: #FFA07D;
  --gold: #D4AF37;

  --ink: #E8EEF5;
  --muted: #8FA3B8;
  --danger: #E45757;

  --font-display: "Inter", "PingFang SC", "Noto Sans SC", system-ui, -apple-system, sans-serif;
  --font-text: "PingFang SC", "Noto Sans SC", "Inter", system-ui, -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --r-card: 22px;
  --r-pill: 999px;
  --w-max: 1440px;
  --pad: clamp(16px, 4vw, 44px);
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 基础排版（中文长文优先） ---------- */
body {
  min-height: 100vh;
  background-color: var(--bg);
  background-image:
    radial-gradient(1100px 560px at 88% -8%, rgba(0, 229, 199, .10), transparent 62%),
    radial-gradient(860px 500px at -6% 16%, rgba(255, 107, 53, .07), transparent 66%),
    linear-gradient(180deg, #0A1A2F 0%, #08152a 100%);
  color: var(--ink);
  font-family: var(--font-text);
  font-size: 16.5px;
  font-weight: 400;
  line-height: 1.75;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 200;
  line-height: 1.14;
  letter-spacing: -.02em;
  color: var(--ink);
}

h1 { font-size: clamp(2.5rem, 6.2vw, 5.4rem); }
h2 { font-size: clamp(1.7rem, 2.6vw, 2.25rem); }
h3 { font-size: clamp(1.1rem, 1.5vw, 1.3rem); font-weight: 400; letter-spacing: -.01em; }
h4 { font-size: 1rem; font-weight: 500; letter-spacing: 0; }

p { max-width: 74ch; }

strong { font-weight: 600; color: #fff; }

a:not([class]) { color: var(--cyan); border-bottom: 1px solid rgba(0, 229, 199, .35); }
a:not([class]):hover { border-bottom-color: var(--cyan); }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 8px;
}

::selection { background: rgba(0, 229, 199, .35); color: #fff; }

.mono { font-family: var(--font-mono); }
.muted { color: var(--muted); }

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ---------- 4. 布局原语 ---------- */
.container {
  width: 100%;
  max-width: var(--w-max);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.container--narrow { max-width: 960px; }

.section { padding-block: clamp(44px, 7vw, 96px); }

.split {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
  gap: clamp(24px, 3.4vw, 56px);
  align-items: start;
}

.split--flip { grid-template-columns: minmax(0, 9fr) minmax(0, 3fr); }

.grid { display: grid; gap: clamp(14px, 1.8vw, 24px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--auto { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

.section__title { margin-bottom: .4em; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: var(--cyan);
  display: block;
}

.lede {
  font-size: clamp(1rem, 1.3vw, 1.12rem);
  color: #C6D4E2;
  max-width: 64ch;
}

.weave {
  height: clamp(36px, 5vw, 64px);
  border-radius: var(--r-card);
  background-image:
    repeating-linear-gradient(108deg, rgba(0, 229, 199, .16) 0 1px, transparent 1px 14px),
    repeating-linear-gradient(108deg, rgba(255, 107, 53, .10) 0 1px, transparent 1px 34px),
    linear-gradient(120deg, rgba(19, 43, 69, .9), rgba(14, 33, 56, .6));
  border: 1px solid var(--line);
}

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  border: 1px solid transparent;
  border-radius: var(--r-pill);
  background: transparent;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: .02em;
  line-height: 1.2;
  cursor: pointer;
  text-align: center;
  transition: background-color .18s var(--ease), color .18s var(--ease),
              border-color .18s var(--ease), box-shadow .18s var(--ease),
              transform .16s var(--ease);
}

.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--cyan);
  color: #08152a;
  font-weight: 600;
  box-shadow: 0 8px 22px rgba(0, 229, 199, .22);
}
.btn--primary:hover { background: var(--cyan-soft); }

.btn--ghost {
  border-color: rgba(0, 229, 199, .42);
  color: var(--cyan);
  background: rgba(0, 229, 199, .05);
}
.btn--ghost:hover { background: rgba(0, 229, 199, .14); }

.btn--warm {
  border-color: rgba(255, 107, 53, .45);
  color: var(--orange-soft);
  background: rgba(255, 107, 53, .09);
}
.btn--warm:hover { background: rgba(255, 107, 53, .18); }

.btn--quiet {
  border-color: var(--line);
  color: var(--muted);
}
.btn--quiet:hover { color: var(--ink); border-color: rgba(0, 229, 199, .5); }

.btn.is-copied {
  border-color: var(--cyan);
  color: var(--cyan);
}

/* ---------- 6. 卡片 · 数字 · 标签 ---------- */
.card {
  position: relative;
  padding: clamp(18px, 2.3vw, 28px);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background: linear-gradient(158deg, rgba(19, 43, 69, .94), rgba(14, 33, 56, .94));
  transition: border-color .2s var(--ease), box-shadow .2s var(--ease), transform .2s var(--ease);
}

.card:hover {
  border-color: rgba(0, 229, 199, .45);
  box-shadow: 0 18px 44px rgba(3, 10, 20, .55);
  transform: translateY(-2px);
}

.card--tint { background: linear-gradient(150deg, rgba(0, 229, 199, .13), rgba(14, 33, 56, .95) 58%); }
.card--warm { background: linear-gradient(150deg, rgba(255, 107, 53, .14), rgba(14, 33, 56, .95) 58%); }

.stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 3.4vw, 2.9rem);
  font-weight: 600;
  letter-spacing: -.02em;
  line-height: 1;
  color: var(--cyan);
}

.stat__label {
  display: block;
  margin-top: 8px;
  font-size: 12.5px;
  letter-spacing: .1em;
  color: var(--muted);
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: rgba(19, 43, 69, .6);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--muted);
}
.pill--cyan { color: var(--cyan); border-color: rgba(0, 229, 199, .35); background: rgba(0, 229, 199, .08); }
.pill--orange { color: var(--orange-soft); border-color: rgba(255, 107, 53, .4); background: rgba(255, 107, 53, .1); }
.pill--gold { color: var(--gold); border-color: rgba(212, 175, 55, .42); background: rgba(212, 175, 55, .08); }

/* ---------- 7. 数据表格 ---------- */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background: rgba(14, 33, 56, .72);
}

.table { min-width: 560px; font-size: 14px; }

.table th,
.table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid rgba(30, 62, 92, .75);
}

.table th {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
}

.table tbody tr:hover { background: rgba(0, 229, 199, .05); }
.table tbody tr:last-child td { border-bottom: 0; }
.table .num { font-family: var(--font-mono); text-align: right; color: var(--cyan); }

/* ---------- 8. 图片容器（页面阶段放置图片/SVG） ---------- */
.figure {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background: linear-gradient(150deg, #132B45 0%, #0E2138 72%);
}

.figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(180deg, rgba(255, 255, 255, .035) 0 1px, transparent 1px 4px);
  mix-blend-mode: overlay;
  pointer-events: none;
}

.figure img,
.figure svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure--16x9 { aspect-ratio: 16 / 9; }
.figure--4x3 { aspect-ratio: 4 / 3; }
.figure--3x2 { aspect-ratio: 3 / 2; }
.figure--1x1 { aspect-ratio: 1 / 1; }
.figure--tall { aspect-ratio: 3 / 4; }

.figure__caption {
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 14px;
  font-size: 12.5px;
  color: var(--muted);
  letter-spacing: .02em;
}

/* ---------- 9. 面包屑与章节索引 ---------- */
.crumb { margin-top: clamp(18px, 3vw, 30px); }

.crumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 12.5px;
  color: var(--muted);
}

.crumb__link { color: var(--muted); transition: color .16s var(--ease); }
.crumb__link:hover { color: var(--cyan); }
.crumb__sep { font-family: var(--font-mono); color: rgba(143, 163, 184, .55); }
.crumb__item[aria-current="page"] { color: var(--ink); }

.toc__list { display: flex; flex-direction: column; gap: 2px; }

.toc__link {
  display: block;
  padding: 8px 12px;
  border-left: 2px solid var(--line);
  font-size: 13.5px;
  color: var(--muted);
  transition: color .18s var(--ease), border-color .18s var(--ease), background-color .18s var(--ease);
}

.toc__link:hover { color: var(--ink); border-left-color: rgba(0, 229, 199, .5); }

.toc__link[aria-current="true"] {
  color: var(--cyan);
  border-left-color: var(--cyan);
  background: linear-gradient(90deg, rgba(0, 229, 199, .12), transparent 85%);
}

/* ---------- 10. 页头：紧凑命令栏 ---------- */
.skip-link {
  position: fixed;
  top: -80px;
  left: 16px;
  z-index: 120;
  padding: 10px 20px;
  border-radius: var(--r-pill);
  background: var(--cyan);
  color: #08152a;
  font-size: 14px;
  font-weight: 600;
  transition: top .2s var(--ease);
}
.skip-link:focus { top: 12px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(10, 26, 47, .9);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
}

.site-header__strip {
  border-bottom: 1px solid rgba(30, 62, 92, .6);
  background: linear-gradient(90deg, rgba(0, 229, 199, .07), transparent 58%);
}

.strip-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  max-width: var(--w-max);
  margin-inline: auto;
  padding: 8px var(--pad);
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  scrollbar-width: none;
}
.chip-row::-webkit-scrollbar { display: none; }

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 3px 12px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: rgba(19, 43, 69, .7);
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--muted);
  white-space: nowrap;
}

.chip--cyan {
  color: var(--cyan);
  border-color: rgba(0, 229, 199, .35);
  background: rgba(0, 229, 199, .08);
}

.chip__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(0, 229, 199, .16);
  animation: chipPulse 2.6s var(--ease) infinite;
}

@keyframes chipPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: .35; }
}

.strip-meta {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
  white-space: nowrap;
}

.site-header__main {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  max-width: var(--w-max);
  margin-inline: auto;
  padding: 12px var(--pad);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  flex: 0 0 auto;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--cyan) 0%, #0BB99F 52%, var(--orange) 100%);
  color: #08152a;
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  box-shadow: 0 6px 20px rgba(0, 229, 199, .25);
}

.brand--footer .brand__mark { width: 46px; height: 46px; }

.brand__lines { display: flex; flex-direction: column; line-height: 1.3; }

.brand__title {
  font-family: var(--font-display);
  font-size: 15.5px;
  font-weight: 600;
  letter-spacing: .02em;
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--muted);
}

/* 导航 */
.nav { margin-left: auto; }

.nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav__item { display: flex; }

.nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 13px;
  border-radius: var(--r-pill);
  font-size: 14px;
  color: var(--muted);
  transition: color .18s var(--ease), background-color .18s var(--ease), box-shadow .18s var(--ease);
}

.nav__link:hover { color: var(--ink); background: rgba(30, 62, 92, .5); }

.nav__idx {
  font-family: var(--font-mono);
  font-size: 10px;
  color: rgba(143, 163, 184, .7);
  transition: color .18s var(--ease);
}

.nav__link:hover .nav__idx { color: var(--cyan); }

.nav__link[aria-current="page"] {
  color: var(--cyan);
  background: rgba(0, 229, 199, .08);
  box-shadow: inset 0 0 0 1px rgba(0, 229, 199, .38);
}
.nav__link[aria-current="page"] .nav__idx { color: var(--cyan); }

.nav__actions { display: none; }

/* 行动按钮组 */
.header-cta {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 16px;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  background: rgba(19, 43, 69, .72);
  color: var(--ink);
  font-family: var(--font-display);
  font-size: 13.5px;
  cursor: pointer;
}

.nav-toggle__bars {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 18px;
}

.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  border-radius: 2px;
  background: var(--cyan);
  transition: transform .2s var(--ease), opacity .2s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

.nav-toggle__text { letter-spacing: .08em; }

/* ---------- 11. 左侧悬浮索引胶囊 ---------- */
.dock {
  position: fixed;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 55;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 12px 10px;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: rgba(14, 33, 56, .88);
  box-shadow: 0 18px 40px rgba(3, 10, 20, .6);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.dock__hint {
  margin-inline: auto;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .22em;
  color: var(--muted);
  writing-mode: vertical-rl;
}

.dock__list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.dock__link {
  display: flex;
  align-items: center;
  padding: 8px;
  border-radius: 14px;
  color: var(--muted);
  transition: background-color .2s var(--ease), color .2s var(--ease);
}

.dock__dot {
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: 1px solid var(--cyan);
  transition: background-color .2s var(--ease), box-shadow .2s var(--ease);
}

.dock__label {
  max-width: 0;
  overflow: hidden;
  white-space: nowrap;
  font-size: 12.5px;
  opacity: 0;
  transition: max-width .26s var(--ease), opacity .2s var(--ease), margin-left .26s var(--ease);
}

.dock:hover .dock__label,
.dock:focus-within .dock__label {
  max-width: 170px;
  margin-left: 10px;
  opacity: 1;
}

.dock__link:hover,
.dock__link:focus-visible { background: rgba(0, 229, 199, .1); color: var(--cyan); }

.dock__link:hover .dock__dot,
.dock__link:focus-visible .dock__dot {
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(0, 229, 199, .2);
}

/* ---------- 12. 顶部阅读进度 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  z-index: 80;
  background: rgba(30, 62, 92, .5);
  pointer-events: none;
}

.scroll-progress__fill {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--gold) 55%, var(--orange));
  box-shadow: 0 0 14px rgba(0, 229, 199, .55);
  transition: width .12s linear;
}

/* ---------- 13. 页脚 ---------- */
.site-footer {
  position: relative;
  z-index: 1;
  margin-top: clamp(56px, 9vw, 120px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, #0E2138 0%, #08152a 68%);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(700px 300px at 10% 0%, rgba(0, 229, 199, .10), transparent 66%),
    radial-gradient(520px 260px at 88% 8%, rgba(255, 107, 53, .08), transparent 70%);
}

.site-footer::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--cyan), var(--gold) 46%, var(--orange));
  opacity: .85;
}

.footer__grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1.9fr) minmax(0, 1.25fr);
  gap: clamp(24px, 4vw, 56px);
  padding-top: clamp(44px, 6vw, 76px);
  padding-bottom: clamp(30px, 4vw, 52px);
}

.footer__brand .brand { margin-bottom: 16px; }

.footer__tagline {
  font-size: 15px;
  color: #C6D4E2;
  max-width: 34ch;
}

.footer__note {
  margin-top: 10px;
  font-size: 13px;
  color: var(--muted);
  max-width: 40ch;
}

.footer__cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.footer__title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer__link {
  display: inline-block;
  padding-bottom: 1px;
  border-bottom: 1px solid transparent;
  font-size: 14.5px;
  color: var(--muted);
  transition: color .16s var(--ease), border-color .16s var(--ease);
}

.footer__link:hover { color: var(--cyan-soft); border-bottom-color: rgba(0, 229, 199, .55); }

.footer__contact {
  padding: clamp(16px, 2vw, 22px);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background: rgba(19, 43, 69, .6);
}

.footer__row {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer__key {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--muted);
}

.footer__val {
  font-size: 14.5px;
  color: var(--ink);
  word-break: break-word;
}

.footer__service {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid rgba(30, 62, 92, .8);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
  max-width: none;
}

.footer__bottom {
  position: relative;
  border-top: 1px solid rgba(30, 62, 92, .75);
  background: rgba(8, 21, 42, .72);
}

.footer__bottom-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  padding-block: 18px;
  font-size: 12.5px;
  color: var(--muted);
}

.footer__legal,
.footer__copy { max-width: none; }

.footer__quick {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.footer__quick .footer__link { font-size: 12.5px; }

/* ---------- 14. 滚动显现 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .5s var(--ease), transform .5s var(--ease);
}

[data-reveal].is-in {
  opacity: 1;
  transform: none;
}

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1200px) {
  .dock { display: none; }
}

@media (max-width: 1080px) {
  .strip-meta { display: none; }

  .chip-row {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  .nav-toggle { display: inline-flex; margin-left: auto; }

  .nav {
    order: 9;
    flex: 1 1 100%;
    margin-left: 0;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height .3s var(--ease), opacity .2s var(--ease);
  }

  .nav[data-open] {
    max-height: 680px;
    opacity: 1;
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 8px 0 6px;
    border-top: 1px solid var(--line);
  }

  .nav__link {
    padding: 12px 14px;
    border-radius: 14px;
    font-size: 15px;
  }

  .nav__actions {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding-bottom: 14px;
  }

  .nav__actions .btn { width: 100%; }

  .header-cta { display: none; }

  .split,
  .split--flip { grid-template-columns: 1fr; }
  .split--flip > .rail { order: 2; }
}

@media (max-width: 980px) {
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer__contact { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  .grid--3,
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 620px) {
  body { font-size: 16px; }

  .site-header__main { gap: 12px; padding-block: 10px; }
  .brand__mark { width: 38px; height: 38px; border-radius: 12px; font-size: 18px; }
  .brand__title { font-size: 14.5px; }
  .brand__sub { font-size: 10px; }

  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }

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

  .footer__bottom-inner { flex-direction: column; align-items: flex-start; }

  .figure--tall { aspect-ratio: 4 / 5; }
}

/* ---------- 16. 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  [data-reveal] { opacity: 1; transform: none; }
  .scroll-progress__fill { transition: none; }
}