/* =====================================================================
   乐竞赛场 · /assets/site.css
   共享外壳样式：reset / 变量 / 中文排版 / 框架头 / 页脚 / 通用组件
   ===================================================================== */

/* ---------- 0. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  background: #06080F;
}

body {
  margin: 0;
  min-height: 100%;
  background: transparent;
  color: #EAF2FF;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 17px;
  font-weight: 400;
  line-height: 1.75;
  letter-spacing: 0.012em;
  overflow-x: hidden;
  padding-top: var(--header-h);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
img, svg, video, canvas { display: block; max-width: 100%; height: auto; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
table { border-collapse: collapse; width: 100%; }
hr { border: 0; }

:focus-visible {
  outline: 2px solid #FFC93C;
  outline-offset: 3px;
  border-radius: 6px;
}

::selection { background: rgba(34, 230, 210, 0.32); color: #EAF2FF; }

/* ---------- 1. 设计变量 ---------- */
:root {
  --ink-900: #06080F;
  --ink-800: #0C1425;
  --ink-700: #16233F;
  --neon: #22E6D2;
  --neon-soft: rgba(34, 230, 210, 0.12);
  --neon-deep: #0E8F84;
  --flame: #FF6A2B;
  --gold: #FFC93C;
  --frost: #EAF2FF;
  --mist: #8FA3C4;
  --green: #3ED598;
  --alert: #FF4D6A;

  --line-soft: rgba(143, 163, 196, 0.20);
  --line-neon: rgba(34, 230, 210, 0.34);

  --font-num: ui-monospace, "SFMono-Regular", "DIN Alternate", "Roboto Mono", Menlo, Consolas, monospace;

  --radius-lg: 26px;
  --radius-md: 16px;
  --radius-sm: 11px;
  --notch: 8px;

  --header-h: 78px;
  --rail-w: 8px;
  --shell: 1240px;
  --shell-wide: 1440px;

  --ease: ease-out;
  --dur-fast: 160ms;
  --dur-block: 420ms;
  --dur-page: 600ms;
}

/* ---------- 2. 环境氛围层 ---------- */
body::before {
  content: "";
  position: fixed;
  inset: -10% -10% -10% -10%;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(58% 46% at 12% 8%, rgba(34, 230, 210, 0.10), transparent 70%),
    radial-gradient(48% 42% at 88% 2%, rgba(255, 106, 43, 0.09), transparent 72%),
    radial-gradient(70% 60% at 50% 110%, rgba(22, 35, 63, 0.9), transparent 70%);
}

body::after {
  content: "";
  position: fixed;
  inset: -30% -30% -30% -30%;
  z-index: -1;
  pointer-events: none;
  opacity: 0.9;
  background-image: repeating-linear-gradient(112deg, rgba(34, 230, 210, 0.055) 0 1px, transparent 1px 104px);
  animation: flow-drift 34s linear infinite;
}

@keyframes flow-drift {
  from { transform: translate3d(0, 0, 0); }
  to { transform: translate3d(-104px, -208px, 0); }
}

/* ---------- 3. 中文排版 ---------- */
h1, h2, h3, h4 {
  color: var(--frost);
  font-weight: 800;
  letter-spacing: -0.015em;
  line-height: 1.2;
}

h1 { font-size: clamp(38px, 6vw, 84px); font-weight: 900; letter-spacing: -0.03em; }
h2 { font-size: clamp(28px, 3.4vw, 46px); font-weight: 900; letter-spacing: -0.02em; }
h3 { font-size: clamp(20px, 2vw, 26px); font-weight: 800; }

p { margin-bottom: 1.05em; }
p:last-child { margin-bottom: 0; }
strong { font-weight: 700; color: var(--frost); }
small { font-size: 13px; color: var(--mist); }

.num,
.mono {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
}

/* ---------- 4. 工具类 ---------- */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 50%;
  top: 6px;
  z-index: 130;
  padding: 11px 20px;
  border-radius: 0 0 14px 14px;
  background: var(--gold);
  color: #1A1200;
  font-size: 15px;
  font-weight: 800;
  letter-spacing: 0.02em;
  transform: translate(-50%, -180%);
  transition: transform var(--dur-fast) var(--ease);
}
.skip-link:focus {
  transform: translate(-50%, 0);
  outline: 2px solid var(--frost);
  outline-offset: 2px;
}

#if-main-content,
#main-content { display: block; }
#main-content { scroll-margin-top: calc(var(--header-h) + 18px); }

.divider {
  height: 1px;
  margin: 0;
  border: 0;
  background: linear-gradient(90deg, transparent, rgba(143, 163, 196, 0.36), transparent);
}

.link-neon {
  color: var(--neon);
  border-bottom: 1px solid rgba(34, 230, 210, 0.42);
  transition: color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}
.link-neon:hover { color: #7CF6EC; border-color: currentColor; }

.tag-row { display: flex; flex-wrap: wrap; gap: 10px; }

/* ---------- 5. 框架式头部 ---------- */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 90;
  background: rgba(6, 8, 15, 0.90);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  border-bottom: 1px solid var(--line-neon);
  transition: background-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}
.site-header[data-scrolled="true"] {
  background: rgba(6, 8, 15, 0.97);
  box-shadow: 0 20px 44px rgba(0, 0, 0, 0.58);
}

.frame-bar {
  position: relative;
  max-width: var(--shell-wide);
  margin: 0 auto;
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 0 20px;
  border-left: 1px solid rgba(34, 230, 210, 0.16);
  border-right: 1px solid rgba(34, 230, 210, 0.16);
}
.frame-bar::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 1px;
  pointer-events: none;
  background: linear-gradient(90deg, transparent, rgba(34, 230, 210, 0.55) 16%, rgba(255, 106, 43, 0.45) 66%, transparent);
}

.frame-rail { display: none; }

/* 品牌 */
.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  color: var(--frost);
}
.wordmark-mark {
  position: relative;
  flex: 0 0 auto;
  width: 40px;
  height: 40px;
  border-radius: 14px 14px 14px 5px;
  background: linear-gradient(145deg, var(--neon), #0B6E67 78%);
  box-shadow: 0 0 0 1px rgba(34, 230, 210, 0.45), 0 12px 26px rgba(34, 230, 210, 0.20);
}
.wordmark-mark::before {
  content: "";
  position: absolute;
  inset: 0;
  margin: auto;
  width: 14px;
  height: 14px;
  border-radius: 4px;
  background: var(--ink-900);
  transform: rotate(-8deg);
}
.wordmark-mark::after {
  content: "";
  position: absolute;
  left: 8px;
  bottom: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--flame);
}
.wordmark-text { display: flex; flex-direction: column; line-height: 1.15; min-width: 0; }
.wordmark-name { font-size: 19px; font-weight: 900; letter-spacing: -0.01em; white-space: nowrap; }
.wordmark-tag { font-size: 12px; font-weight: 500; letter-spacing: 0.14em; color: var(--mist); white-space: nowrap; }

/* 导航 */
.frame-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: center;
  min-width: 0;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.frame-nav::-webkit-scrollbar { width: 0; height: 0; display: none; }

.nav-list { display: flex; align-items: center; gap: 2px; padding: 6px 0; }
.nav-item { display: block; }

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 9px 13px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 600;
  color: var(--mist);
  white-space: nowrap;
  transition: color var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}
.nav-link::after {
  content: "";
  position: absolute;
  left: 13px; right: 13px; bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--neon);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 220ms var(--ease);
}
.nav-link:hover { color: var(--frost); background: rgba(34, 230, 210, 0.07); }
.nav-link:hover::after { transform: scaleX(1); }
.nav-link[aria-current="page"] { color: var(--frost); background: rgba(34, 230, 210, 0.12); }
.nav-link[aria-current="page"]::after { transform: scaleX(1); }

.nav-foot { display: none; }

/* 右侧动作区 */
.frame-actions { display: flex; align-items: center; gap: 10px; flex: 0 0 auto; margin-left: auto; }

/* 移动菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 14px 14px 14px 5px;
  border: 1px solid var(--line-neon);
  background: rgba(22, 35, 63, 0.60);
  color: var(--frost);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  transition: border-color var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease);
}
.nav-toggle:hover { border-color: var(--neon); background: rgba(34, 230, 210, 0.10); }
.nav-toggle-label { white-space: nowrap; }
.nav-toggle-bars { display: grid; gap: 4px; width: 18px; }
.nav-toggle-bars i {
  display: block;
  width: 18px;
  height: 2px;
  border-radius: 2px;
  background: var(--neon);
  transition: transform 200ms var(--ease), opacity 160ms var(--ease), width 200ms var(--ease);
}
.nav-toggle-bars i:nth-child(3) { width: 12px; margin-left: auto; }

.frame-nav[data-open] ~ .frame-actions .nav-toggle-bars i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.frame-nav[data-open] ~ .frame-actions .nav-toggle-bars i:nth-child(2) { opacity: 0; }
.frame-nav[data-open] ~ .frame-actions .nav-toggle-bars i:nth-child(3) { width: 18px; margin-left: 0; transform: translateY(-6px) rotate(-45deg); }

/* 阅读进度 */
.progress-track {
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 2px;
  overflow: hidden;
  pointer-events: none;
  background: rgba(143, 163, 196, 0.14);
}
.progress-fill {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--neon), var(--flame));
  transition: width 120ms linear;
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 22px;
  border: 1px solid transparent;
  border-radius: 14px 14px 14px 5px;
  font-family: inherit;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1.2;
  text-align: center;
  cursor: pointer;
  transition: transform var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}
.btn:active { transform: translateY(1px); }
.btn-sm { padding: 10px 16px; font-size: 14px; border-radius: 12px 12px 12px 4px; }
.btn-block { width: 100%; }

.btn-primary {
  background: var(--neon);
  color: #031513;
  box-shadow: 0 12px 28px rgba(34, 230, 210, 0.24);
}
.btn-primary:hover {
  background: #5BF1E3;
  transform: translateY(-2px);
  box-shadow: 0 16px 32px rgba(34, 230, 210, 0.32);
}

.btn-ghost {
  background: rgba(22, 35, 63, 0.55);
  color: var(--frost);
  border-color: rgba(143, 163, 196, 0.42);
}
.btn-ghost:hover {
  border-color: var(--flame);
  box-shadow: 0 0 0 1px rgba(255, 106, 43, 0.35);
  transform: translateY(-2px);
}

/* ---------- 7. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: 96px;
  overflow: hidden;
  color: var(--mist);
  font-size: 15px;
  background: linear-gradient(180deg, var(--ink-800) 0%, var(--ink-900) 62%);
  border-top: 1px solid var(--line-neon);
}
.site-footer::before {
  content: "";
  position: absolute;
  top: 0; right: 0;
  width: min(48%, 540px);
  height: 100%;
  pointer-events: none;
  background: linear-gradient(215deg, rgba(34, 230, 210, 0.12), rgba(255, 106, 43, 0.07) 42%, transparent 74%);
  clip-path: polygon(20% 0, 100% 0, 100% 100%, 0 100%);
}
.site-footer::after {
  content: "";
  position: absolute;
  left: 0; top: 0;
  width: 128px;
  height: 2px;
  pointer-events: none;
  background: var(--flame);
}

.footer-inner {
  position: relative;
  z-index: 1;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 76px 24px 32px;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(240px, 1fr) minmax(0, 1.9fr);
  gap: 48px;
  align-items: start;
}

.footer-brand { display: flex; flex-direction: column; gap: 22px; }
.wordmark--footer .wordmark-mark { width: 34px; height: 34px; border-radius: 12px 12px 12px 4px; }
.wordmark--footer .wordmark-name { font-size: 18px; }

.footer-slogan {
  margin: 0;
  padding-left: 16px;
  border-left: 3px solid var(--neon);
  color: var(--frost);
  font-size: clamp(20px, 2.2vw, 26px);
  font-weight: 900;
  line-height: 1.4;
  letter-spacing: -0.01em;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 32px;
}

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

.footer-col-title {
  position: relative;
  margin: 0 0 16px;
  padding-left: 16px;
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0.16em;
  color: var(--frost);
}
.footer-col-title::before {
  content: "";
  position: absolute;
  left: 0; top: 50%;
  width: 8px; height: 8px;
  margin-top: -4px;
  border-radius: 3px;
  background: var(--gold);
  transform: rotate(-8deg);
  box-shadow: 0 0 12px rgba(255, 201, 60, 0.5);
}

.footer-links { display: grid; gap: 11px; }
.footer-links a {
  display: inline-block;
  color: var(--mist);
  font-size: 15px;
  transition: color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.footer-links a:hover { color: var(--neon); transform: translateX(3px); }

.footer-contact {
  margin-top: 52px;
  padding-top: 36px;
  border-top: 1px solid rgba(143, 163, 196, 0.20);
}

.contact-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(258px, 1fr));
  gap: 16px 24px;
}

.contact-line {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-rows: auto auto;
  gap: 4px 14px;
  padding: 14px 16px;
  background: rgba(22, 35, 63, 0.55);
  border: 1px solid var(--line-soft);
  border-radius: 16px 16px 16px 5px;
  transition: border-color var(--dur-fast) var(--ease);
}
.contact-line:hover { border-color: rgba(34, 230, 210, 0.42); }

.contact-label {
  grid-column: 1 / 2;
  grid-row: 1 / 2;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--mist);
}
.contact-value {
  grid-column: 1 / 2;
  grid-row: 2 / 3;
  color: var(--frost);
  font-size: 15px;
  line-height: 1.6;
  word-break: break-word;
}

.copy-btn {
  grid-column: 2 / 3;
  grid-row: 1 / 3;
  align-self: center;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 62px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line-neon);
  background: rgba(34, 230, 210, 0.08);
  color: var(--neon);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  transition: background-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}
.copy-btn:hover { background: rgba(34, 230, 210, 0.18); border-color: var(--neon); }
.copy-btn.is-copied { background: var(--neon); border-color: var(--neon); color: #031513; }

.footer-note {
  margin: 18px 0 0;
  max-width: 64ch;
  color: var(--mist);
  font-size: 13px;
  line-height: 1.75;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 28px;
  margin-top: 44px;
  padding-top: 22px;
  border-top: 1px solid rgba(143, 163, 196, 0.20);
}

.footer-credit { margin: 0; font-size: 13px; letter-spacing: 0.04em; color: var(--mist); }
.footer-legal { display: flex; flex-wrap: wrap; gap: 8px 20px; margin: 0; }
.footer-legal a { font-size: 13px; color: var(--mist); transition: color var(--dur-fast) var(--ease); }
.footer-legal a:hover { color: var(--neon); }
.footer-icp {
  margin: 0 0 0 auto;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--mist);
}

/* ---------- 8. 容器 · 章节 · 栅格 ---------- */
.container {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: 24px;
}
.container-wide { max-width: var(--shell-wide); }
.container-narrow { max-width: 760px; }

.section { padding: 96px 0; }
.section--tight { padding: 56px 0; }
.section--deep { background: var(--ink-800); }
.section--panel { background: linear-gradient(180deg, var(--ink-900), var(--ink-800)); }

.section-head { display: grid; gap: 14px; max-width: 760px; margin-bottom: 40px; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--neon);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.18em;
}
.eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  border-radius: 2px;
  background: var(--neon);
}

.section-title { margin: 0; }
.lede {
  max-width: 62ch;
  margin: 0;
  color: var(--mist);
  font-size: clamp(16px, 1.4vw, 19px);
  line-height: 1.85;
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}
.col-3 { grid-column: span 3; }
.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-9 { grid-column: span 9; }
.col-12 { grid-column: span 12; }

/* ---------- 9. 面包屑 ---------- */
.breadcrumbs {
  padding-top: 22px;
  color: var(--mist);
  font-size: 13px;
  letter-spacing: 0.04em;
}
.breadcrumb-list { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.breadcrumb-list li { display: inline-flex; align-items: center; gap: 8px; }
.breadcrumb-list li + li::before {
  content: "";
  width: 7px;
  height: 1px;
  background: var(--mist);
  opacity: 0.7;
}
.breadcrumb-list a { color: var(--mist); transition: color var(--dur-fast) var(--ease); }
.breadcrumb-list a:hover { color: var(--neon); }
.breadcrumb-list [aria-current="page"] { color: var(--frost); font-weight: 600; }

/* ---------- 10. 卡片 · 面板 · 标签 · 指标 ---------- */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 26px;
  background: rgba(22, 35, 63, 0.82);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg) var(--radius-lg) var(--radius-lg) var(--notch);
  transition: transform var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), background-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}
.card:hover {
  transform: translateY(-4px);
  border-color: rgba(34, 230, 210, 0.62);
  background: rgba(22, 35, 63, 0.95);
  box-shadow: 0 22px 46px rgba(3, 6, 14, 0.62);
}
.card--flame:hover { border-color: rgba(255, 106, 43, 0.72); }
.card--gold:hover { border-color: rgba(255, 201, 60, 0.76); }

.card-title { margin: 0; font-size: 20px; font-weight: 800; }
.card-text { margin: 0; color: var(--mist); font-size: 15px; line-height: 1.75; }

.panel {
  padding: 30px;
  background: rgba(12, 20, 37, 0.86);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg) var(--radius-lg) var(--radius-lg) var(--notch);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 13px;
  border: 1px solid rgba(34, 230, 210, 0.35);
  border-radius: 999px;
  background: rgba(34, 230, 210, 0.09);
  color: var(--neon);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: 0.1em;
  white-space: nowrap;
}
.chip--flame {
  color: var(--frost);
  border-color: rgba(255, 106, 43, 0.55);
  background: rgba(255, 106, 43, 0.12);
}
.chip--flame::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--flame);
  box-shadow: 0 0 10px rgba(255, 106, 43, 0.85);
}
.chip--gold {
  color: var(--gold);
  border-color: rgba(255, 201, 60, 0.5);
  background: rgba(255, 201, 60, 0.10);
}
.chip--mute {
  color: var(--mist);
  border-color: var(--line-soft);
  background: rgba(143, 163, 196, 0.10);
}

.dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 3px rgba(62, 213, 152, 0.16);
}
.dot--warn { background: var(--alert); box-shadow: 0 0 0 3px rgba(255, 77, 106, 0.16); }
.dot--live { animation: dot-pulse 2.4s ease-out infinite; }

@keyframes dot-pulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(62, 213, 152, 0.16); }
  50% { box-shadow: 0 0 0 8px rgba(62, 213, 152, 0.03); }
}

.stat { display: flex; flex-direction: column; gap: 6px; }
.stat-value {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-weight: 800;
  font-size: clamp(34px, 4.4vw, 64px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--frost);
}
.stat-value--neon { color: var(--neon); }
.stat-value--flame { color: var(--flame); }
.stat-value--gold { color: var(--gold); }
.stat-label { font-size: 13px; font-weight: 600; letter-spacing: 0.1em; color: var(--mist); }

/* ---------- 11. 图文容器 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-lg) var(--radius-lg) var(--radius-lg) var(--notch);
  background:
    radial-gradient(70% 60% at 20% 12%, rgba(34, 230, 210, 0.14), transparent 66%),
    linear-gradient(150deg, var(--ink-700), var(--ink-800) 72%);
}
.media > img,
.media > video,
.media > svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.media::after {
  content: "";
  position: absolute;
  left: 0; top: 0;
  width: 58px;
  height: 58px;
  pointer-events: none;
  background: linear-gradient(135deg, rgba(34, 230, 210, 0.55), transparent 62%);
  clip-path: polygon(0 0, 100% 0, 0 100%);
}
.media--wide { aspect-ratio: 21 / 9; }
.media--square { aspect-ratio: 1 / 1; }
.media--portrait { aspect-ratio: 3 / 4; }
.media--tall { aspect-ratio: 9 / 16; }

.media-frame {
  padding: 12px;
  border: 1px solid var(--line-soft);
  border-radius: 30px 30px 30px 12px;
  background: rgba(22, 35, 63, 0.48);
}

.media-caption {
  margin: 10px 0 0;
  color: var(--mist);
  font-size: 13px;
  letter-spacing: 0.04em;
  line-height: 1.7;
}

/* ---------- 12. 滚动显现协议 ---------- */
html.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur-block) var(--ease), transform var(--dur-block) var(--ease);
}
html.has-js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 13. 响应式 ---------- */
@media (max-width: 1279px) {
  :root { --shell-wide: 1200px; }
}

@media (max-width: 1199px) {
  .frame-actions .btn-ghost { display: none; }
  .nav-link { padding: 9px 11px; font-size: 14px; }
  .nav-link::after { left: 11px; right: 11px; }
}

@media (max-width: 1023px) {
  :root { --header-h: 66px; }

  .frame-nav {
    position: fixed;
    left: 0;
    right: 0;
    top: var(--header-h);
    z-index: 89;
    display: block;
    padding: 16px 18px 24px;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    overflow-x: hidden;
    background: linear-gradient(180deg, rgba(12, 20, 37, 0.99), rgba(6, 8, 15, 0.99));
    border-top: 1px solid rgba(34, 230, 210, 0.20);
    border-bottom: 1px solid rgba(34, 230, 210, 0.35);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.62);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-14px);
    transition: opacity 220ms var(--ease), transform 280ms var(--ease), visibility 280ms var(--ease);
  }
  .frame-nav[data-open] {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 4px; padding: 0; }
  .nav-item { width: 100%; }
  .nav-link {
    width: 100%;
    padding: 14px 15px;
    border-radius: 14px 14px 14px 5px;
    font-size: 17px;
  }
  .nav-link::after { display: none; }
  .nav-link:hover { box-shadow: inset 3px 0 0 rgba(255, 106, 43, 0.85); }
  .nav-link[aria-current="page"] { box-shadow: inset 3px 0 0 var(--neon); }

  .nav-foot {
    display: grid;
    gap: 10px;
    margin-top: 18px;
    padding-top: 18px;
    border-top: 1px dashed rgba(143, 163, 196, 0.28);
  }

  .frame-actions .btn { display: none; }
  .nav-toggle { display: inline-flex; }
  .wordmark-tag { display: none; }

  .footer-top { grid-template-columns: 1fr; gap: 36px; }
  .footer-inner { padding: 60px 20px 28px; }
}

@media (max-width: 960px) {
  body { font-size: 16px; line-height: 1.72; }
  .section { padding: 68px 0; }
  .section--tight { padding: 42px 0; }
  .grid { gap: 18px; }
  .col-3, .col-4, .col-5, .col-6 { grid-column: span 6; }
  .col-7, .col-8, .col-9 { grid-column: span 12; }
  .panel { padding: 24px; }
}

@media (max-width: 720px) {
  .frame-bar { padding: 0 16px; gap: 14px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 26px; }
  .footer-contact { margin-top: 40px; padding-top: 28px; }
  .contact-list { grid-template-columns: 1fr; }
  .site-footer { margin-top: 64px; }
  .footer-icp { margin-left: 0; }
  .media--wide { aspect-ratio: 16 / 9; }
}

@media (max-width: 640px) {
  :root { --header-h: 60px; }
  .frame-bar { padding: 0 14px; }
  .wordmark-mark { width: 34px; height: 34px; border-radius: 12px 12px 12px 4px; }
  .wordmark-name { font-size: 17px; }
  .nav-toggle-label { display: none; }

  .container { padding-inline: 18px; }
  .grid { grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
  .col-3, .col-4, .col-5, .col-6,
  .col-7, .col-8, .col-9, .col-12 { grid-column: span 4; }

  .card { padding: 22px; }
  .footer-grid { grid-template-columns: 1fr; gap: 24px; }
}

@media (min-width: 1280px) {
  .frame-rail {
    display: block;
    position: fixed;
    top: 0; bottom: 0; left: 0;
    width: var(--rail-w);
    z-index: 88;
    pointer-events: none;
    opacity: 0.85;
    background:
      repeating-linear-gradient(180deg, rgba(234, 242, 255, 0.16) 0 1px, transparent 1px 48px),
      linear-gradient(180deg, rgba(34, 230, 210, 0.75), rgba(34, 230, 210, 0.05) 46%, rgba(255, 106, 43, 0.55));
  }
}

/* ---------- 14. 无障碍降级 ---------- */
@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;
  }

  body::after { animation: none; }

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