/* =========================================================
   新世纪体育赛 · /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 头部 / 页脚 / 基础组件
   ========================================================= */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 128px;
}

body,
h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd, address {
  margin: 0;
}

ul, ol { padding: 0; list-style: none; }

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

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

button { background: none; border: 0; padding: 0; }

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

/* ---------- 2. 变量 ---------- */
:root {
  --ink-900: #04091a;
  --ink-800: #070e22;
  --ink-700: #0c1730;
  --ink-600: #132241;

  --text-hi: #f1f5ff;
  --text-mid: #a7b6d4;
  --text-low: #6d7d9c;

  --cyan: #2ff0d6;
  --cyan-soft: rgba(47, 240, 214, 0.12);
  --cyan-line: rgba(47, 240, 214, 0.34);
  --blue: #3c7cff;
  --orange: #ff6a3d;

  --line: rgba(122, 176, 255, 0.16);
  --line-strong: rgba(122, 216, 255, 0.34);

  --radius-lg: 28px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --radius-pill: 999px;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC",
    system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  --wrap: 1200px;
  --shadow-card: 0 22px 48px rgba(2, 6, 18, 0.55);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100%;
  background-color: var(--ink-900);
  background-image:
    radial-gradient(1100px 620px at 10% -10%, rgba(60, 124, 255, 0.22), transparent 62%),
    radial-gradient(900px 520px at 92% 2%, rgba(47, 240, 214, 0.14), transparent 60%),
    linear-gradient(180deg, var(--ink-800), var(--ink-900) 42%);
  background-repeat: no-repeat;
  color: var(--text-mid);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  color: var(--text-hi);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(30px, 5vw, 52px); }
h2 { font-size: clamp(24px, 3.4vw, 36px); }
h3 { font-size: clamp(18px, 2.2vw, 24px); }
h4 { font-size: 17px; }

p { line-height: 1.9; }

strong { color: var(--text-hi); font-weight: 700; }

::selection { background: rgba(47, 240, 214, 0.28); color: #ffffff; }

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

/* ---------- 4. 布局 ---------- */
.container {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 40px);
}

.section { padding-block: clamp(40px, 6vw, 88px); }
.section-tight { padding-block: clamp(26px, 3.6vw, 52px); }

.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 28px);
}

.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-split {
  grid-template-columns: minmax(230px, 0.82fr) minmax(0, 1.68fr);
  align-items: start;
}

.divider {
  height: 1px;
  border: 0;
  margin-block: clamp(28px, 4vw, 56px);
  background: linear-gradient(90deg, var(--cyan-line), rgba(255, 106, 61, 0.28) 55%, transparent);
}

.measure { max-width: 68ch; }

/* ---------- 5. 文字工具 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan), transparent);
}

.display {
  font-size: clamp(32px, 6vw, 66px);
  font-weight: 800;
  line-height: 1.04;
  letter-spacing: -0.03em;
  color: var(--text-hi);
}

.lede {
  max-width: 64ch;
  font-size: clamp(15.5px, 1.6vw, 18px);
  line-height: 1.95;
  color: var(--text-mid);
}

.mono { font-family: var(--font-mono); letter-spacing: 0.06em; }
.text-cyan { color: var(--cyan); }
.text-accent { color: var(--orange); }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 18px;
  padding-bottom: 18px;
  margin-bottom: clamp(22px, 3vw, 36px);
  border-bottom: 1px solid var(--line);
}

.section-title {
  font-size: clamp(22px, 3vw, 34px);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-hi);
}

.section-lede {
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.9;
  color: var(--text-mid);
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---------- 6. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: -90px;
  left: 16px;
  z-index: 140;
  padding: 11px 20px;
  border-radius: var(--radius-pill);
  background: var(--cyan);
  color: #04231f;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.02em;
  transition: top 0.2s ease;
}

.skip-link:focus,
.skip-link:focus-visible { top: 14px; }

/* ---------- 7. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  color: var(--text-mid);
  background: linear-gradient(180deg, rgba(5, 10, 24, 0.97), rgba(5, 10, 24, 0.88));
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--cyan), var(--blue) 55%, var(--orange));
  will-change: transform;
}

.header-inner { position: relative; }

.header-tier {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
}

.header-tier-top {
  padding-block: 14px;
  border-bottom: 1px solid var(--line);
}

.header-tier-nav { padding-block: 8px 10px; }

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

.brand-mark {
  position: relative;
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  border: 1px solid var(--line-strong);
  background: linear-gradient(145deg, rgba(47, 240, 214, 0.22), rgba(60, 124, 255, 0.28));
}

.brand-mark::before {
  content: "";
  width: 15px;
  height: 15px;
  border: 2px solid var(--cyan);
  border-radius: 50%;
}

.brand-mark-dot {
  position: absolute;
  right: 8px;
  bottom: 8px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 12px rgba(255, 106, 61, 0.85);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.24;
}

.brand-name {
  color: var(--text-hi);
  font-size: 19px;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.brand-note {
  flex: 1 1 auto;
  min-width: 0;
  padding-left: clamp(14px, 2.4vw, 30px);
  border-left: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: 0.04em;
  color: var(--text-low);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 在线状态胶囊（头部与页脚共用） */
.header-status,
.footer-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--cyan-line);
  background: var(--cyan-soft);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.12em;
  color: var(--cyan);
  white-space: nowrap;
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
  animation: status-pulse 2.4s ease-out infinite;
}

@keyframes status-pulse {
  0% { box-shadow: 0 0 0 0 rgba(47, 240, 214, 0.55); }
  70% { box-shadow: 0 0 0 9px rgba(47, 240, 214, 0); }
  100% { box-shadow: 0 0 0 0 rgba(47, 240, 214, 0); }
}

.status-text { color: inherit; }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 16px 10px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line-strong);
  background: rgba(47, 240, 214, 0.06);
  color: var(--cyan);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.nav-toggle:hover { border-color: var(--cyan); background: rgba(47, 240, 214, 0.14); }

.nav-toggle-bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
  transition: transform 0.22s ease, opacity 0.22s ease;
}

.nav-toggle-bars::before { top: -6px; }
.nav-toggle-bars::after { top: 6px; }

.site-header[data-open] .nav-toggle-bars { background: transparent; }
.site-header[data-open] .nav-toggle-bars::before { transform: translateY(6px) rotate(45deg); }
.site-header[data-open] .nav-toggle-bars::after { transform: translateY(-6px) rotate(-45deg); }

.nav-toggle-label { font-family: var(--font-mono); font-size: 12px; }

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(10px, 2vw, 26px);
  width: 100%;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: clamp(2px, 0.9vw, 8px);
}

.nav-link {
  position: relative;
  display: inline-block;
  padding: 8px 12px;
  border-radius: 10px;
  font-size: 14.5px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--text-mid);
  transition: color 0.18s ease, background-color 0.18s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 0.22s ease, background-color 0.22s ease;
}

.nav-link:hover {
  color: var(--text-hi);
  background: rgba(122, 176, 255, 0.09);
}

.nav-link:hover::after { transform: scaleX(1); }

.nav-link[aria-current="page"] { color: var(--text-hi); }
.nav-link[aria-current="page"]::after { transform: scaleX(1); background: var(--orange); }

.nav-cta { margin-left: auto; flex: 0 0 auto; }

/* ---------- 8. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: transform 0.16s ease, background-color 0.18s ease, color 0.18s ease,
    border-color 0.18s ease, box-shadow 0.18s ease;
}

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

.btn-primary {
  background: var(--cyan);
  color: #04231f;
  box-shadow: 0 10px 28px rgba(47, 240, 214, 0.22);
}

.btn-primary:hover { background: #63f6e4; }

.btn-ghost {
  border-color: var(--line-strong);
  background: rgba(122, 176, 255, 0.05);
  color: var(--text-hi);
}

.btn-ghost:hover { border-color: var(--cyan); color: var(--cyan); }

.btn-quiet {
  background: var(--cyan-soft);
  color: var(--cyan);
}

.btn-quiet:hover { background: rgba(47, 240, 214, 0.2); }

/* ---------- 9. 页脚 ---------- */
.site-footer {
  margin-top: clamp(48px, 8vw, 110px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(7, 14, 34, 0.72), rgba(3, 7, 16, 0.97));
  color: var(--text-mid);
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(250px, 1.4fr) repeat(2, minmax(150px, 1fr)) minmax(220px, 1.2fr);
  gap: clamp(24px, 3vw, 44px);
  padding-block: clamp(38px, 5vw, 66px);
}

.footer-brand { max-width: 36ch; }

.brand-footer { margin-bottom: 4px; }

.footer-tagline {
  margin-top: 16px;
  font-size: 14px;
  line-height: 1.85;
  color: var(--text-mid);
}

.footer-status { margin-top: 18px; }

.footer-col { min-width: 0; }

.footer-title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.18em;
  color: var(--cyan);
}

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

.footer-link {
  display: inline-block;
  font-size: 14.5px;
  color: var(--text-mid);
  transition: color 0.18s ease, padding-left 0.2s ease;
}

.footer-link:hover { color: var(--cyan); padding-left: 4px; }

.footer-link[aria-current="page"] { color: var(--text-hi); }

.footer-address {
  display: grid;
  gap: 10px;
  font-style: normal;
  font-size: 14px;
  line-height: 1.75;
}

.contact-line {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 10px;
  align-items: start;
}

.contact-label {
  padding-top: 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--text-low);
  white-space: nowrap;
}

.contact-value { color: var(--text-mid); overflow-wrap: anywhere; }

.footer-note {
  margin-top: 16px;
  padding-left: 12px;
  border-left: 2px solid var(--cyan-line);
  font-size: 12.5px;
  line-height: 1.8;
  color: var(--text-low);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 28px;
  padding-block: 20px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--text-low);
}

.footer-copy { color: var(--text-low); }
.footer-icp { color: var(--text-mid); }
.footer-meta { color: var(--text-low); }

/* ---------- 10. 基础组件 ---------- */
/* 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--text-low);
}

.breadcrumbs a { color: var(--text-low); transition: color 0.18s ease; }
.breadcrumbs a:hover { color: var(--cyan); }

.crumb { color: var(--text-low); }
.crumb[aria-current="page"] { color: var(--cyan); }
.crumb-sep { color: rgba(122, 176, 255, 0.42); }

/* 徽标 */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 6px 13px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: rgba(122, 176, 255, 0.06);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--text-mid);
}

.pill-accent {
  border-color: rgba(255, 106, 61, 0.42);
  background: rgba(255, 106, 61, 0.12);
  color: #ffb69c;
}

/* 卡片 */
.card {
  position: relative;
  padding: clamp(18px, 2.4vw, 28px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(19, 34, 65, 0.92), rgba(7, 14, 34, 0.88));
  transition: border-color 0.2s ease, transform 0.2s ease, box-shadow 0.25s ease;
}

.card:hover {
  border-color: var(--line-strong);
  transform: translateY(-3px);
  box-shadow: var(--shadow-card);
}

.card-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 14px;
}

.card-title {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--text-hi);
}

.card-body {
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-mid);
}

/* 数据 */
.stat { display: grid; gap: 6px; }

.stat-value {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.4vw, 40px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--text-hi);
}

.unit {
  margin-left: 6px;
  font-family: var(--font-mono);
  font-size: 0.5em;
  letter-spacing: 0.02em;
  color: var(--cyan);
}

.stat-label {
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--text-low);
}

/* 时间线 */
.timeline {
  position: relative;
  display: grid;
  gap: clamp(18px, 2.6vw, 30px);
  padding-left: clamp(22px, 3vw, 34px);
}

.timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan), rgba(255, 106, 61, 0.5) 70%, transparent);
}

.timeline-item { position: relative; }

.timeline-marker {
  position: absolute;
  left: calc(-1 * clamp(22px, 3vw, 34px) + 0px);
  top: 8px;
  width: 11px;
  height: 11px;
  border: 2px solid var(--cyan);
  border-radius: 50%;
  background: var(--ink-900);
}

/* 展开组 */
.accordion { display: grid; gap: 12px; }

.accordion-item {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(12, 23, 48, 0.72);
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.accordion-item[data-open] {
  border-color: var(--line-strong);
  background: rgba(19, 34, 65, 0.92);
}

.accordion-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 16px clamp(16px, 2vw, 22px);
  text-align: left;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-hi);
  cursor: pointer;
  transition: color 0.18s ease;
}

.accordion-trigger:hover { color: var(--cyan); }

.accordion-icon {
  position: relative;
  flex: 0 0 auto;
  width: 22px;
  height: 22px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
}

.accordion-icon::before,
.accordion-icon::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  background: var(--cyan);
  border-radius: 2px;
}

.accordion-icon::before { width: 10px; height: 2px; }

.accordion-icon::after {
  width: 2px;
  height: 10px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.accordion-trigger[aria-expanded="true"] .accordion-icon::after {
  transform: translate(-50%, -50%) scaleY(0);
  opacity: 0;
}

.accordion-panel {
  padding: 0 clamp(16px, 2vw, 22px) 20px;
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--text-mid);
}

.accordion-panel[hidden] { display: none; }

/* 图片容器 */
.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, rgba(47, 240, 214, 0.14), rgba(60, 124, 255, 0.18) 48%, rgba(255, 106, 61, 0.14));
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: radial-gradient(120% 90% at 14% 8%, rgba(47, 240, 214, 0.18), transparent 56%);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-wide { aspect-ratio: 16 / 9; }
.media-square { aspect-ratio: 1 / 1; }
.media-portrait { aspect-ratio: 4 / 5; }

.media-caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--text-low);
}

/* 显现节奏 */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

html.js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 11. 响应式 ---------- */
@media (max-width: 1079px) {
  .brand-note { display: none; }
}

@media (max-width: 1023px) {
  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(24px, 5vw, 40px);
  }
}

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

  .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 899px) {
  html { scroll-padding-top: 150px; }

  .header-tier-top { padding-block: 12px; }
  .header-status { display: none; }
  .nav-toggle { display: inline-flex; margin-left: auto; }

  .header-tier-nav {
    padding-block: 0;
    border: 0;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
    padding: 18px clamp(18px, 4vw, 40px) 24px;
    background: #070e22;
    border-bottom: 1px solid var(--line-strong);
    box-shadow: 0 26px 54px rgba(2, 6, 16, 0.62);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 0.2s ease, transform 0.22s ease, visibility 0.2s ease;
  }

  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }

  .nav-link {
    display: block;
    padding: 12px 14px;
    border-radius: var(--radius-sm);
    font-size: 16px;
  }

  .nav-link::after { left: 14px; right: 14px; bottom: 6px; }

  .nav-cta {
    width: 100%;
    margin: 16px 0 0;
  }
}

@media (max-width: 640px) {
  body { font-size: 15.5px; }

  .grid-4 { grid-template-columns: minmax(0, 1fr); }

  .brand-name { font-size: 17px; }
  .brand-mark { width: 38px; height: 38px; border-radius: 12px; }

  .media-wide { aspect-ratio: 4 / 3; }

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

  .footer-base {
    justify-content: flex-start;
    gap: 8px 18px;
  }
}

/* ---------- 12. 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .status-dot { animation: none; }

  html.js [data-reveal] {
    opacity: 1;
    transform: none;
  }
}