/* ==========================================================================
   完美体育入口 — 共享样式 /assets/site.css
   1 重置  2 变量  3 基础与中文排版  4 头部  5 页脚  6 通用组件  7 动效无障碍
   ========================================================================== */

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

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

body,
h1, h2, h3, h4, h5, h6,
p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }

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

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

button, input, select, textarea {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
}

button { cursor: pointer; }

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

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

[hidden] { display: none !important; }

/* ---------- 2. 变量 ---------- */
:root {
  /* 色板 */
  --ink: #04170F;
  --ink-2: #0A2A22;
  --ink-3: #0F3B33;
  --night: #061E1A;
  --cyan: #14E0C0;
  --cyan-soft: #7CF7E4;
  --pulse: #FF5A2E;
  --amber: #FFB020;
  --paper: #EAF7F4;
  --muted: #8FB3AC;
  --line: #1E3A34;
  --glass: rgba(20, 224, 192, 0.08);
  --glass-strong: rgba(20, 224, 192, 0.16);
  --glass-line: rgba(20, 224, 192, 0.18);
  --shadow-cyan: 0 18px 44px -26px rgba(20, 224, 192, 0.75);
  --shadow-pulse: 0 14px 32px -18px rgba(255, 90, 46, 0.9);

  /* 字体 */
  --font-display: "HarmonyOS Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-body: "PingFang SC", "HarmonyOS Sans SC", "Noto Sans SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --font-serif: "Noto Serif SC", "Songti SC", "Source Han Serif SC", Georgia, "Times New Roman", serif;

  /* 尺度 */
  --shell-max: 1240px;
  --gutter: 20px;
  --header-h: 72px;
  --radius-s: 10px;
  --radius: 16px;
  --radius-l: 24px;
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
}

/* ---------- 3. 基础与中文排版 ---------- */
body {
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.8;
  color: var(--paper);
  background-color: var(--ink);
  background-image:
    radial-gradient(1200px 620px at 84% -12%, rgba(20, 224, 192, 0.11), transparent 62%),
    radial-gradient(900px 520px at 6% 6%, rgba(255, 90, 46, 0.07), transparent 60%),
    linear-gradient(180deg, #04170F 0%, #061E1A 100%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--paper);
}

p { text-wrap: pretty; }

strong { font-weight: 700; }

::selection {
  background: var(--cyan);
  color: var(--ink);
}

#main-content {
  display: block;
  scroll-margin-top: 96px;
}

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

/* ---------- 4. 头部 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 200;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan), var(--cyan-soft));
  box-shadow: 0 0 12px rgba(20, 224, 192, 0.6);
  pointer-events: none;
}

.skip-link {
  position: fixed;
  top: -80px;
  left: var(--gutter);
  z-index: 220;
  padding: 10px 20px;
  border-radius: 999px;
  background: var(--cyan);
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
  transition: top 0.2s var(--ease);
}

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

.site-header {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 150;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background 0.28s var(--ease), border-color 0.28s var(--ease),
    backdrop-filter 0.28s var(--ease);
}

.site-header[data-scrolled="true"] {
  background: rgba(4, 23, 15, 0.93);
  border-bottom-color: var(--line);
  backdrop-filter: blur(16px) saturate(150%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 22px;
  width: min(100% - (var(--gutter) * 2), var(--shell-max));
  min-height: var(--header-h);
  margin-inline: auto;
  transition: min-height 0.28s var(--ease);
}

.site-header[data-scrolled="true"] .header-inner {
  min-height: 56px;
}

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

.brand-mark {
  display: grid;
  flex: none;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 11px;
  background: linear-gradient(140deg, var(--cyan), var(--cyan-soft));
  box-shadow: 0 0 0 1px rgba(124, 247, 228, 0.35), 0 10px 26px -16px var(--cyan);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  line-height: 1.15;
}

.brand-name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.brand--footer .brand-name { font-size: 16px; }
.brand--footer .brand-mark { width: 34px; height: 34px; border-radius: 10px; font-size: 12px; }

/* 主导航 */
.nav {
  flex: 1 1 auto;
  min-width: 0;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-item { display: flex; }

.nav-link {
  display: inline-block;
  padding: 9px 13px;
  border-radius: 999px;
  color: rgba(234, 247, 244, 0.82);
  font-size: 14.5px;
  font-weight: 500;
  white-space: nowrap;
  transition: color 0.18s var(--ease), background 0.18s var(--ease);
}

.nav-link:hover {
  color: var(--paper);
  background: var(--glass);
}

.nav-link[aria-current="page"] {
  color: var(--cyan);
  background: var(--glass-strong);
  box-shadow: inset 0 0 0 1px var(--glass-line);
}

.nav-extra { display: none; }

.nav-extra-note {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

/* 右侧工具区 */
.header-actions {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 10px;
  margin-left: auto;
}

.utility-chip {
  padding: 5px 11px;
  border: 1px solid rgba(255, 176, 32, 0.32);
  border-radius: 999px;
  background: rgba(255, 176, 32, 0.07);
  color: var(--amber);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

.utility-chip--lang {
  border-color: var(--line);
  background: transparent;
  color: var(--muted);
}

/* 汉堡按钮 */
.nav-toggle {
  position: relative;
  z-index: 170;
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 14px;
  border: 1px solid rgba(20, 224, 192, 0.35);
  border-radius: 999px;
  background: var(--glass);
  color: var(--paper);
  font-size: 13px;
  font-weight: 600;
}

.nav-toggle-bars {
  display: grid;
  gap: 4px;
  width: 18px;
}

.nav-toggle-bar {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform 0.22s var(--ease), opacity 0.18s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

body.is-nav-open { overflow: hidden; }

/* ---------- 5. 页脚 ---------- */
.site-footer {
  margin-top: 96px;
  padding: 64px 0 28px;
  background: linear-gradient(180deg, #061E1A 0%, #03110B 100%);
  border-top: 1px solid var(--line);
  color: var(--muted);
}

.footer-inner {
  width: min(100% - (var(--gutter) * 2), var(--shell-max));
  margin-inline: auto;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(220px, 1.05fr) minmax(0, 1.9fr) minmax(230px, 1.2fr);
  gap: 48px;
  align-items: start;
}

.footer-brand {
  display: grid;
  gap: 16px;
}

.footer-tagline {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: rgba(234, 247, 244, 0.72);
}

.footer-update {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--amber);
  font-size: 13px;
}

.footer-update::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--amber);
  animation: fw-pulse 2.4s var(--ease) infinite;
}

@keyframes fw-pulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(255, 176, 32, 0.5); }
  50% { opacity: 0.55; box-shadow: 0 0 0 7px rgba(255, 176, 32, 0); }
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
}

.footer-col { display: grid; gap: 14px; align-content: start; }

.footer-col-title {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cyan);
}

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

.footer-links a {
  display: inline-block;
  color: rgba(234, 247, 244, 0.78);
  font-size: 14.5px;
  transition: color 0.18s var(--ease), transform 0.18s var(--ease);
}

.footer-links a:hover {
  color: var(--cyan);
  transform: translateX(3px);
}

.footer-contact {
  display: grid;
  gap: 12px;
  align-content: start;
}

.contact-line {
  display: grid;
  gap: 3px;
}

.contact-label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(143, 179, 172, 0.68);
}

.contact-value {
  font-family: var(--font-mono);
  font-size: 13.5px;
  letter-spacing: 0.01em;
  color: var(--paper);
  word-break: break-word;
}

.contact-note {
  margin-top: 4px;
  font-size: 12.5px;
  line-height: 1.75;
  color: rgba(143, 179, 172, 0.9);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
  align-items: center;
  justify-content: space-between;
  margin-top: 48px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(143, 179, 172, 0.88);
}

.legal-item { letter-spacing: 0.02em; }

.legal-item--update {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--amber);
}

.legal-item--update::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--amber);
  animation: fw-pulse 2.4s var(--ease) infinite;
}

/* ---------- 6. 通用组件 ---------- */
.shell {
  width: min(100% - (var(--gutter) * 2), var(--shell-max));
  margin-inline: auto;
}

.page-offset { padding-top: calc(var(--header-h) + 24px); }

.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;
}

.section { padding: 72px 0; }
.section--tight { padding: 44px 0; }

.section-head {
  display: grid;
  gap: 14px;
  max-width: 780px;
  margin-bottom: 34px;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow--amber { color: var(--amber); }
.eyebrow--pulse { color: var(--pulse); }

.section-title {
  font-size: clamp(1.7rem, 3.4vw, 2.7rem);
}

.section-lead {
  max-width: 62ch;
  color: var(--muted);
  font-size: 16.5px;
}

.serif-note {
  font-family: var(--font-serif);
  font-size: 17px;
  line-height: 1.75;
  color: var(--cyan-soft);
}

.divider {
  height: 1px;
  border: 0;
  background: linear-gradient(90deg, transparent, var(--line), transparent);
}

.canvas { position: relative; }

.canvas--alt {
  background: linear-gradient(180deg, transparent, rgba(10, 42, 34, 0.75) 10%, rgba(10, 42, 34, 0.75) 90%, transparent);
}

/* 栅格 */
.grid { display: grid; gap: 20px; }
.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)); }

/* 层级面板：实色内容层 */
.panel {
  position: relative;
  padding: 24px;
  border-radius: var(--radius);
  background: var(--ink-2);
}

.panel--deep { background: var(--ink-3); }

/* 玻璃功能层 */
.glass-panel {
  position: relative;
  padding: 22px;
  border: 1px solid var(--glass-line);
  border-radius: var(--radius);
  background: var(--glass);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
}

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border-radius: 999px;
  background: var(--glass-strong);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  white-space: nowrap;
}

.tag--pulse { background: rgba(255, 90, 46, 0.15); color: #FF8A66; }
.tag--amber { background: rgba(255, 176, 32, 0.13); color: var(--amber); }
.tag--quiet { background: rgba(143, 179, 172, 0.1); color: var(--muted); }

/* 数据 */
.stat-value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3vw, 2.3rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.stat-value--cyan { color: var(--cyan); }
.stat-value--pulse { color: #FF8A66; }
.stat-value--amber { color: var(--amber); }

.stat-label {
  margin-top: 8px;
  font-size: 12.5px;
  letter-spacing: 0.02em;
  color: var(--muted);
}

/* 编辑部目录 */
.index-list {
  display: grid;
  gap: 2px;
}

.index-row {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: 18px;
  align-items: baseline;
  padding: 16px 6px;
  border-bottom: 1px solid var(--line);
  transition: background 0.18s var(--ease), padding-left 0.18s var(--ease);
}

.index-row:hover {
  background: linear-gradient(90deg, var(--glass), transparent);
  padding-left: 14px;
}

.index-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.index-title {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--paper);
}

.index-meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
  white-space: nowrap;
}

/* 横向滚动带 */
.rail { position: relative; overflow: hidden; }

.rail-track {
  display: flex;
  gap: 20px;
  padding: 4px 4px 20px;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  cursor: grab;
  scrollbar-width: thin;
  scrollbar-color: rgba(20, 224, 192, 0.4) transparent;
}

.rail-track.is-dragging { cursor: grabbing; scroll-snap-type: none; }

.rail-track::-webkit-scrollbar { height: 6px; }
.rail-track::-webkit-scrollbar-track { background: transparent; }
.rail-track::-webkit-scrollbar-thumb {
  border-radius: 999px;
  background: rgba(20, 224, 192, 0.35);
}

.rail-item {
  flex: 0 0 320px;
  min-width: 0;
  scroll-snap-align: start;
}

.rail--bleed {
  width: 100vw;
  margin-left: calc(50% - 50vw);
  padding-inline: clamp(20px, (100vw - var(--shell-max)) / 2, 240px);
}

/* 图片容器基础规则 */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border-radius: var(--radius);
  background: linear-gradient(140deg, #0F3B33 0%, #061E1A 100%);
}

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

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(4, 23, 15, 0) 42%, rgba(4, 23, 15, 0.74) 100%);
  pointer-events: none;
}

.media-frame--bare::after { display: none; }
.media-frame--thumb { aspect-ratio: 4 / 3; border-radius: var(--radius-s); }
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--portrait { aspect-ratio: 3 / 4; }

.media-frame-cap {
  position: absolute;
  right: 16px;
  bottom: 14px;
  left: 16px;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--paper);
}

/* 筛选 */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.filter-btn {
  padding: 8px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  transition: color 0.18s var(--ease), background 0.18s var(--ease),
    border-color 0.18s var(--ease);
}

.filter-btn:hover {
  border-color: rgba(20, 224, 192, 0.5);
  color: var(--paper);
}

.filter-btn[aria-pressed="true"] {
  border-color: var(--cyan);
  background: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  padding: 20px 0;
}

.breadcrumb-item {
  display: flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin: 0 10px;
  color: rgba(143, 179, 172, 0.45);
}

.breadcrumb-item a { transition: color 0.16s var(--ease); }
.breadcrumb-item a:hover { color: var(--cyan); }
.breadcrumb-item [aria-current="page"] { color: var(--paper); }

/* 正文 */
.prose {
  display: grid;
  gap: 18px;
  max-width: 70ch;
}

.prose h2 {
  margin-top: 14px;
  font-size: clamp(1.3rem, 2.4vw, 1.7rem);
}

.prose h3 {
  margin-top: 8px;
  font-size: 1.12rem;
}

.prose p { color: rgba(234, 247, 244, 0.86); }

.prose a {
  color: var(--cyan);
  text-decoration: underline;
  text-decoration-color: rgba(20, 224, 192, 0.4);
  text-underline-offset: 3px;
}

.prose a:hover { text-decoration-color: var(--cyan); }

.prose ul, .prose ol {
  display: grid;
  gap: 10px;
  padding-left: 20px;
  list-style: disc;
  color: rgba(234, 247, 244, 0.86);
}

.callout {
  padding: 16px 20px;
  border-left: 2px solid var(--cyan);
  border-radius: 0 12px 12px 0;
  background: linear-gradient(90deg, var(--glass), transparent);
  font-family: var(--font-serif);
  font-size: 16.5px;
  line-height: 1.75;
  color: var(--cyan-soft);
}

.callout--amber {
  border-left-color: var(--amber);
  background: linear-gradient(90deg, rgba(255, 176, 32, 0.1), transparent);
  color: #FFD48A;
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: var(--font-body);
  font-size: 14.5px;
  font-weight: 700;
  letter-spacing: 0.01em;
  white-space: nowrap;
  transition: transform 0.16s var(--ease), background 0.16s var(--ease),
    color 0.16s var(--ease), border-color 0.16s var(--ease), box-shadow 0.16s var(--ease);
}

.btn--primary {
  background: var(--pulse);
  color: #1A0A04;
  box-shadow: var(--shadow-pulse);
}

.btn--primary:hover {
  transform: translateY(-1px);
  background: #FF7346;
}

.btn--ghost {
  border-color: rgba(20, 224, 192, 0.42);
  background: var(--glass);
  color: var(--cyan);
}

.btn--ghost:hover {
  background: var(--glass-strong);
  color: var(--cyan-soft);
}

.btn--quiet {
  border-color: var(--line);
  color: var(--muted);
}

.btn--quiet:hover {
  border-color: rgba(20, 224, 192, 0.42);
  color: var(--paper);
}

.btn--block {
  display: flex;
  width: 100%;
}

/* 悬浮快捷坞（由 JS 注入） */
.dock {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 130;
  display: grid;
  gap: 10px;
  justify-items: end;
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity 0.24s var(--ease), transform 0.24s var(--ease);
}

.dock[data-visible="true"] {
  opacity: 1;
  transform: none;
  pointer-events: auto;
}

.dock-btn {
  display: inline-grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border: 1px solid rgba(20, 224, 192, 0.32);
  border-radius: 50%;
  background: rgba(6, 30, 26, 0.88);
  color: var(--cyan);
  font-size: 17px;
  line-height: 1;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: background 0.18s var(--ease), transform 0.18s var(--ease);
}

.dock-btn:hover {
  background: rgba(20, 224, 192, 0.18);
  transform: translateY(-2px);
}

.dock-btn--label {
  width: auto;
  height: 42px;
  padding: 0 18px;
  border-radius: 999px;
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 700;
}

/* 入场动效（仅在 JS 标记 data-motion="on" 时隐藏初始态） */
html[data-motion="on"] [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
}

html[data-motion="on"] [data-reveal][data-shown="true"] {
  opacity: 1;
  transform: none;
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
}

/* ---------- 7. 响应式 ---------- */
@media (max-width: 1280px) {
  .utility-chip { display: none; }
}

@media (max-width: 1024px) {
  .header-cta { display: none; }
  .nav-toggle { display: inline-flex; }

  .nav {
    position: fixed;
    inset: 0;
    z-index: 160;
    display: flex;
    flex-direction: column;
    padding: 96px var(--gutter) 40px;
    overflow-y: auto;
    background: linear-gradient(180deg, #04170F 0%, #061E1A 100%);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-3%);
    transition: opacity 0.24s var(--ease), transform 0.3s var(--ease), visibility 0.3s;
  }

  .nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-item { display: block; }

  .nav-link {
    display: block;
    padding: 16px 2px;
    border-bottom: 1px solid var(--line);
    border-radius: 0;
    font-family: var(--font-display);
    font-size: 21px;
    font-weight: 800;
    letter-spacing: -0.01em;
    background: none;
  }

  .nav-link[aria-current="page"] {
    color: var(--cyan);
    background: none;
    box-shadow: none;
  }

  .nav-extra {
    display: grid;
    gap: 12px;
    margin-top: 28px;
  }

  .footer-top {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 36px;
  }

  .footer-contact { grid-column: 1 / -1; }
}

@media (max-width: 980px) {
  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 760px) {
  body { font-size: 16px; }
  :root { --gutter: 16px; --header-h: 64px; }
  .section { padding: 56px 0; }
  .section--tight { padding: 36px 0; }
  .brand-sub { display: none; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid .footer-col:last-child { grid-column: 1 / -1; }
  .footer-legal { justify-content: flex-start; }
  .dock { right: 14px; bottom: 14px; }
}

@media (max-width: 640px) {
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .rail-item { flex-basis: 78vw; }
  .footer-top { grid-template-columns: minmax(0, 1fr); gap: 30px; }
  .footer-contact { grid-column: auto; }
  .index-row { grid-template-columns: auto minmax(0, 1fr); }
  .index-meta { grid-column: 2; }
}

@media (max-width: 420px) {
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-grid .footer-col:last-child { grid-column: auto; }
}

/* ---------- 8. 动效无障碍 ---------- */
@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;
  }

  html[data-motion="on"] [data-reveal],
  html[data-motion="on"] [data-reveal][data-shown="true"] {
    opacity: 1;
    transform: none;
  }

  .dock { transform: none; }
}