/* ============================================================
   OG视讯厅 · 共享站点样式 /assets/site.css
   视觉母题：夜间直播控制台 / 通道指示灯 / 雾面玻璃层叠面板
   ============================================================ */

/* ---------- 1. 变量 ---------- */
:root {
  /* 色彩 */
  --abyss: #061626;
  --panel: #0B2338;
  --panel-2: #12405F;
  --cyan: #34E2D4;
  --cyan-deep: #1FA9C9;
  --coral: #FF6B4A;
  --green: #57D68A;
  --amber: #FFB547;
  --text: #E9F2F8;
  --muted: #93AEC2;
  --line: #1D4A63;
  --glass: rgba(233, 242, 248, 0.08);
  --glass-strong: rgba(233, 242, 248, 0.14);

  /* 字体 */
  --font-sans: "Inter", "Source Han Sans SC", "Noto Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas,
    "Liberation Mono", monospace;

  /* 字号阶梯 13 / 15 / 17 / 21 / 28 / 40 / 56 */
  --fs-13: 13px;
  --fs-15: 15px;
  --fs-17: 17px;
  --fs-21: 21px;
  --fs-28: clamp(22px, 2.6vw, 28px);
  --fs-40: clamp(27px, 4vw, 40px);
  --fs-56: clamp(32px, 5.4vw, 56px);

  /* 尺度 */
  --wrap-max: 1240px;
  --rail-w: 220px;
  --radius-s: 10px;
  --radius-m: 14px;
  --radius-l: 18px;
  --radius-xl: 22px;
  --header-h: 148px;
}

/* ---------- 2. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 160px;
}

body {
  margin: 0;
  min-height: 100vh;
  background-color: var(--abyss);
  background-image:
    radial-gradient(120% 80% at 50% -10%, rgba(31, 169, 201, 0.14), rgba(6, 22, 38, 0) 62%);
  background-repeat: no-repeat;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: var(--fs-17);
  line-height: 1.75;
  letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

h1, h2, h3, h4, h5 {
  margin: 0 0 0.6em;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.3;
  color: var(--text);
}
h1 { font-size: var(--fs-56); }
h2 { font-size: var(--fs-40); }
h3 { font-size: var(--fs-28); }
h4 { font-size: var(--fs-21); }
h5 { font-size: var(--fs-17); }

p { margin: 0 0 1em; }
ul, ol { margin: 0 0 1em; padding-left: 1.25em; }
li { margin-bottom: 0.35em; }

a {
  color: var(--cyan);
  text-decoration: none;
  transition: color 180ms ease-out, opacity 180ms ease-out;
}
a:hover { color: #74F1E6; }

strong, b { font-weight: 600; }
small { font-size: var(--fs-13); }
hr { border: 0; border-top: 1px solid var(--line); margin: 40px 0; }

::selection {
  background: rgba(52, 226, 212, 0.28);
  color: #FFFFFF;
}

/* ---------- 3. 字体工具 ---------- */
.mono {
  font-family: var(--font-mono);
  font-size: 0.88em;
  letter-spacing: 0.04em;
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
}

/* ---------- 4. 焦点与可达性 ---------- */
:where(a, button, summary, input, select, textarea, [tabindex]):focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  left: 20px;
  top: -72px;
  z-index: 200;
  padding: 10px 20px;
  border-radius: 0 0 var(--radius-s) var(--radius-s);
  background: var(--cyan);
  color: var(--abyss);
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  transition: top 180ms ease-out;
}
.skip-link:hover,
.skip-link:focus { top: 0; color: var(--abyss); }

/* ---------- 5. 布局容器 ---------- */
.wrap {
  width: min(100% - 48px, var(--wrap-max));
  margin-inline: auto;
}

.with-rail {
  display: grid;
  grid-template-columns: var(--rail-w) minmax(0, 1fr);
  gap: 40px;
  width: min(100% - 48px, calc(var(--wrap-max) + var(--rail-w) + 40px));
  margin-inline: auto;
}

/* ---------- 6. 页头 · 居中刊头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background:
    linear-gradient(180deg, rgba(6, 22, 38, 0.97), rgba(6, 22, 38, 0.9));
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: linear-gradient(90deg, var(--cyan-deep), var(--cyan));
  transform: scaleX(var(--scroll-progress, 0));
  transform-origin: 0 50%;
  pointer-events: none;
}

.masthead__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 16px 24px;
  padding: 22px 0 0;
}

.signal {
  margin: 0;
  justify-self: start;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.signal__dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 4px rgba(87, 214, 138, 0.16);
  flex: none;
}

.signal__text { white-space: nowrap; }

@keyframes signal-breathe {
  0%, 100% {
    opacity: 1;
    box-shadow: 0 0 0 4px rgba(87, 214, 138, 0.18);
  }
  50% {
    opacity: 0.62;
    box-shadow: 0 0 0 9px rgba(87, 214, 138, 0.04);
  }
}

.signal__dot--pulse { animation: signal-breathe 3.6s ease-in-out infinite; }

.masthead__brand {
  justify-self: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
  color: var(--text);
  text-align: center;
}
.masthead__brand:hover { color: var(--text); }

.masthead__name {
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.1;
}

.masthead__tag {
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.18em;
  color: var(--cyan);
  opacity: 0.86;
}

.masthead__actions {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 10px;
}

.masthead__region {
  border-bottom: 1px solid var(--line);
  padding: 10px 0 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.06em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.masthead__region > .wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
}
.masthead__sep { color: var(--line); }

/* 收拢态 */
.site-header[data-condensed] .masthead__region { display: none; }
.site-header[data-condensed] .masthead__inner { padding: 12px 0; }
.site-header[data-condensed] .masthead__tag { display: none; }
.site-header[data-condensed] .masthead__name { font-size: 22px; }
.site-header[data-condensed] .primary-nav__list a { padding-block: 9px; }

/* ---------- 7. 主导航 ---------- */
.primary-nav {
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(11, 35, 56, 0.5), rgba(6, 22, 38, 0));
}

.primary-nav__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: stretch;
  gap: 2px;
}
.primary-nav__list > li { margin: 0; }

.primary-nav__list a {
  position: relative;
  display: block;
  padding: 13px 20px;
  font-size: var(--fs-15);
  letter-spacing: 0.02em;
  color: var(--muted);
  white-space: nowrap;
}

.primary-nav__list a::after {
  content: "";
  position: absolute;
  left: 20px;
  right: 20px;
  bottom: 5px;
  height: 2px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: 50% 50%;
  transition: transform 180ms ease-out;
}

.primary-nav__list a:hover { color: var(--text); }
.primary-nav__list a:hover::after { transform: scaleX(1); }

.primary-nav__list a[aria-current="page"] { color: var(--text); }
.primary-nav__list a[aria-current="page"]::after { transform: scaleX(1); }

/* ---------- 8. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--glass);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  line-height: 1.4;
  cursor: pointer;
  transition: background 180ms ease-out, border-color 180ms ease-out,
    color 180ms ease-out, transform 180ms ease-out;
}
.btn:hover {
  background: var(--glass-strong);
  border-color: var(--cyan);
  color: var(--cyan);
}
.btn:active { transform: translateY(1px); }

.btn--coral {
  background: var(--coral);
  border-color: var(--coral);
  color: var(--abyss);
  font-weight: 500;
}
.btn--coral:hover {
  background: #FF8163;
  border-color: #FF8163;
  color: var(--abyss);
}

.btn--ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--muted);
}
.btn--ghost:hover {
  background: var(--glass);
  border-color: var(--cyan);
  color: var(--cyan);
}

/* ---------- 9. 移动端栏目开关 ---------- */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-s);
  background: var(--glass);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: border-color 180ms ease-out, color 180ms ease-out;
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: var(--cyan);
  flex: none;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: var(--cyan);
}
.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }

.nav-toggle[aria-expanded="true"] {
  border-color: var(--coral);
  color: var(--coral);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars,
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before,
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after {
  background: var(--coral);
}

/* ---------- 10. 通用内容区块 ---------- */
.panel {
  border: 1px solid var(--line);
  border-radius: var(--radius-l);
  padding: 26px 26px 20px;
  background:
    linear-gradient(180deg, rgba(11, 35, 56, 0.92), rgba(6, 22, 38, 0.68));
}
.panel > :last-child { margin-bottom: 0; }

.slab {
  border-top: 1px solid var(--line);
  padding: 34px 0;
}
.slab > :last-child { margin-bottom: 0; }

.band {
  border-block: 1px solid var(--line);
  background-color: var(--panel);
  background-image:
    radial-gradient(90% 140% at 10% 0%, rgba(31, 169, 201, 0.2), rgba(6, 22, 38, 0) 62%),
    radial-gradient(70% 120% at 94% 6%, rgba(52, 226, 212, 0.12), rgba(6, 22, 38, 0) 58%);
  padding: 56px 0;
}

.grid {
  display: grid;
  gap: 24px;
}
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--5-7 { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); }
.grid--7-5 { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.grid--index {
  grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
  gap: 0 24px;
}

/* ---------- 11. 章节标题 / 状态条 / 元信息 ---------- */
.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px 24px;
  padding-bottom: 14px;
  margin-bottom: 30px;
  border-bottom: 1px solid var(--line);
}
.section-head__title { margin: 0; }
.section-head__note {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.06em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.signal-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 28px;
  padding: 13px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: linear-gradient(90deg, rgba(18, 64, 95, 0.55), rgba(6, 22, 38, 0.3));
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.signal-bar > span { display: inline-flex; align-items: center; gap: 8px; }

.meta-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 18px;
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

/* ---------- 12. 细线清单 ---------- */
.line-list {
  list-style: none;
  margin: 0;
  padding: 0;
}
.line-list > li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding: 14px 0;
  margin: 0;
  border-top: 1px solid var(--line);
}
.line-list > li:last-child { border-bottom: 1px solid var(--line); }

/* ---------- 13. 标签与状态灯 ---------- */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--glass);
  color: var(--muted);
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  text-decoration: none;
  font-variant-numeric: tabular-nums;
  transition: color 180ms ease-out, border-color 180ms ease-out,
    background 180ms ease-out;
}
.pill:hover {
  color: var(--cyan);
  border-color: var(--cyan);
  background: var(--glass-strong);
}
.pill--on {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--abyss);
}
.pill--on:hover { color: var(--abyss); }

.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--green);
  flex: none;
  box-shadow: 0 0 0 3px rgba(87, 214, 138, 0.14);
}
.status-dot--busy {
  background: var(--amber);
  box-shadow: 0 0 0 3px rgba(255, 181, 71, 0.14);
}
.status-dot--off {
  background: var(--muted);
  box-shadow: 0 0 0 3px rgba(147, 174, 194, 0.12);
}
.status-dot--pulse { animation: signal-breathe 3.6s ease-in-out infinite; }

/* ---------- 14. 图片容器基础规则 ---------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-l);
  background-color: var(--panel);
  background-image:
    radial-gradient(120% 110% at 14% 0%, rgba(52, 226, 212, 0.16), rgba(6, 22, 38, 0) 62%),
    radial-gradient(90% 120% at 96% 94%, rgba(255, 107, 74, 0.1), rgba(6, 22, 38, 0) 58%);
  aspect-ratio: var(--frame-ratio, 16 / 9);
}

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

.media-frame--tall { --frame-ratio: 4 / 5; }
.media-frame--wide { --frame-ratio: 21 / 9; }
.media-frame--phone {
  --frame-ratio: 9 / 19.5;
  width: 100%;
  max-width: 300px;
}

.media-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  margin: 0;
  padding: 30px 16px 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--text);
  background: linear-gradient(180deg, rgba(6, 22, 38, 0), rgba(6, 22, 38, 0.88));
}

/* ---------- 15. 面包屑与正文容器 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 22px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--muted);
}
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--cyan); }
.breadcrumb__sep { color: var(--line); }
.breadcrumb [aria-current="page"] { color: var(--text); }

.prose {
  max-width: 68ch;
  font-size: var(--fs-17);
  line-height: 1.75;
}
.prose > :last-child { margin-bottom: 0; }
.prose h2 { margin-top: 1.8em; }
.prose h3 { margin-top: 1.5em; }
.prose ul,
.prose ol { padding-left: 1.3em; }
.prose li { margin-bottom: 0.5em; }

/* ---------- 16. 折叠说明 ---------- */
.fold {
  border-top: 1px solid var(--line);
}
.fold:last-of-type { border-bottom: 1px solid var(--line); }

.fold__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-sans);
  font-size: var(--fs-17);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
  transition: color 180ms ease-out;
}
.fold__head::-webkit-details-marker { display: none; }
.fold__head:hover { color: var(--cyan); }

.fold__mark {
  font-family: var(--font-mono);
  font-size: var(--fs-17);
  color: var(--cyan);
  transition: transform 260ms ease-out;
  flex: none;
}
.fold[open] .fold__mark { transform: rotate(45deg); }

.fold__body {
  padding: 0 0 22px;
  font-size: var(--fs-15);
  color: var(--muted);
  line-height: 1.75;
}
.fold__body > :last-child { margin-bottom: 0; }

/* ---------- 17. 左侧纵向标签轨道 ---------- */
.rail {
  align-self: start;
  position: sticky;
  top: calc(var(--header-h) + 20px);
  border-left: 1px solid var(--line);
}

.rail__title {
  margin: 0;
  padding: 0 0 12px 16px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  font-weight: 400;
  letter-spacing: 0.16em;
  color: var(--muted);
  border-bottom: 1px solid var(--line);
}

.rail__link {
  position: relative;
  display: block;
  padding: 11px 14px 11px 16px;
  border-bottom: 1px solid rgba(29, 74, 99, 0.55);
  font-size: var(--fs-15);
  color: var(--muted);
  transition: color 180ms ease-out, background 180ms ease-out;
}
.rail__link::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: transparent;
  transition: background 180ms ease-out;
}
.rail__link:hover {
  color: var(--text);
  background: var(--glass);
}
.rail__link[aria-current="true"] {
  color: var(--cyan);
  background: var(--glass);
}
.rail__link[aria-current="true"]::before { background: var(--cyan); }

/* ---------- 18. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 88;
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: rgba(11, 35, 56, 0.9);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: var(--fs-15);
  line-height: 1;
  cursor: pointer;
  transition: border-color 180ms ease-out, color 180ms ease-out;
}
.to-top[data-visible] { display: grid; place-items: center; }
.to-top:hover { border-color: var(--cyan); color: var(--text); }

/* ---------- 19. 页脚 ---------- */
.site-footer {
  margin-top: 96px;
  padding: 64px 0 32px;
  border-top: 1px solid var(--line);
  background-color: var(--panel);
  background-image:
    radial-gradient(80% 130% at 6% 0%, rgba(31, 169, 201, 0.16), rgba(6, 22, 38, 0) 60%),
    radial-gradient(60% 120% at 96% 10%, rgba(52, 226, 212, 0.08), rgba(6, 22, 38, 0) 58%);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr 1fr;
  gap: 32px 28px;
}

.footer-brand__name {
  margin: 0 0 8px;
  font-size: var(--fs-21);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
}
.footer-brand__line {
  margin: 0 0 12px;
  max-width: 30ch;
  font-size: var(--fs-15);
  color: var(--muted);
  line-height: 1.7;
}
.footer-brand__meta {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.06em;
  color: var(--cyan);
  font-variant-numeric: tabular-nums;
}

.footer-col__title {
  margin: 0 0 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  font-weight: 400;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.footer-col__list {
  list-style: none;
  margin: 0;
  padding: 0;
}
.footer-col__list > li { margin: 0 0 8px; }
.footer-col__list a {
  font-size: var(--fs-15);
  color: var(--muted);
}
.footer-col__list a:hover { color: var(--cyan); }

.footer-contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 16px 32px;
  margin-top: 48px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.footer-contact__item {
  margin: 0;
  font-size: var(--fs-15);
  color: var(--muted);
  line-height: 1.7;
}

.footer-contact__key {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.1em;
  color: var(--cyan);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  margin-top: 32px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.04em;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}
.footer-legal__item {
  margin: 0;
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}
.footer-legal a { color: var(--muted); }
.footer-legal a:hover { color: var(--cyan); }

/* ---------- 20. 平板 ---------- */
@media (max-width: 1080px) {
  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 32px 24px;
  }
  .footer-brand { grid-column: 1 / -1; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* ---------- 21. 移动端 ---------- */
@media (max-width: 900px) {
  :root { --header-h: 118px; }

  html { scroll-padding-top: 128px; }

  .wrap,
  .with-rail { width: min(100% - 32px, var(--wrap-max)); }

  .with-rail {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .rail {
    position: static;
    top: auto;
    border-left: 0;
    border-top: 1px solid var(--line);
  }
  .rail__title { padding: 14px 0 10px; border-bottom: 1px solid var(--line); }
  .rail__link { padding: 10px 0 10px 14px; }
  .rail__link::before { left: 0; top: 10px; bottom: 10px; }

  /* 刊头 */
  .masthead__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-areas:
      "brand actions"
      "signal signal";
    gap: 4px 12px;
    padding: 14px 0 0;
  }
  .masthead__brand {
    grid-area: brand;
    justify-self: start;
    align-items: flex-start;
    text-align: left;
  }
  .masthead__name { font-size: 22px; }
  .masthead__tag { letter-spacing: 0.12em; }
  .masthead__actions { grid-area: actions; }
  .signal {
    grid-area: signal;
    justify-self: start;
    padding-bottom: 4px;
  }

  .masthead__actions .btn--coral {
    padding: 9px 14px;
    font-size: var(--fs-13);
  }

  .nav-toggle { display: inline-flex; }

  /* 导航 */
  .primary-nav { display: none; }
  .primary-nav[data-open] { display: block; }

  .primary-nav__list {
    flex-direction: column;
    justify-content: flex-start;
    gap: 0;
    padding: 6px 0 14px;
  }
  .primary-nav__list > li { border-bottom: 1px solid rgba(29, 74, 99, 0.6); }
  .primary-nav__list a {
    padding: 15px 4px;
    font-size: var(--fs-17);
  }
  .primary-nav__list a::after { display: none; }
  .primary-nav__list a[aria-current="page"] {
    color: var(--cyan);
    padding-left: 16px;
  }
  .primary-nav__list a[aria-current="page"]::before {
    content: "";
    position: absolute;
    left: 0;
    top: 18px;
    bottom: 18px;
    width: 2px;
    background: var(--cyan);
  }

  /* 网格塌陷 */
  .grid--2,
  .grid--3,
  .grid--5-7,
  .grid--7-5 { grid-template-columns: minmax(0, 1fr); }

  .panel { padding: 20px 18px 16px; }
  .band { padding: 40px 0; }
  .slab { padding: 26px 0; }
  .site-footer { margin-top: 64px; padding: 44px 0 26px; }
  .footer-legal { flex-direction: column; align-items: flex-start; }
  .to-top { right: 14px; bottom: 14px; }
}

@media (max-width: 560px) {
  body { font-size: var(--fs-15); }
  .masthead__actions .btn--coral { display: none; }
  .masthead__region { font-size: 12px; }
  .signal-bar { gap: 8px 18px; padding: 12px 14px; }
  .media-frame--phone { max-width: 100%; }
}

/* ---------- 22. 动效降级 ---------- */
@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;
    scroll-behavior: auto !important;
  }

  .signal__dot--pulse,
  .status-dot--pulse { animation: none; }
}