/* ==========================================================================
   乐竞体育赛场 — 共享样式表 /assets/site.css
   赛场深蓝打底 · 荧光青动线 · 暖橙关键点 · L 形框架导航
   ========================================================================== */

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

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

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

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

a { color: inherit; }

button { font: inherit; color: inherit; background: none; border: 0; padding: 0; }

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

h1, h2, h3, h4 { line-height: 1.22; font-weight: 700; }

/* ---------- 2. 变量 ---------- */
:root {
  color-scheme: dark;

  --arena: #061224;
  --night: #0C2038;
  --line: #1B3552;
  --glass: rgba(122, 190, 255, 0.10);
  --glass-line: rgba(122, 190, 255, 0.18);
  --neon: #2FF3D0;
  --neon-soft: #8DF8E4;
  --ember: #FF8A2B;
  --amber: #FFC24B;
  --paper: #F2F7FF;
  --mist: #9FB3CC;
  --ink: #04201b;

  --sans: system-ui, -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --mono: ui-monospace, 'JetBrains Mono', 'SF Mono', 'Cascadia Mono', Menlo, Consolas, 'Courier New', monospace;

  --top-h: 62px;
  --rail-w: 252px;
  --pad-x: clamp(18px, 4vw, 56px);

  --radius-s: 10px;
  --radius-m: 16px;
  --radius-l: 24px;

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --dur: 320ms;
}

/* ---------- 3. 基础排版 ---------- */
html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

body {
  min-height: 100vh;
  padding-top: var(--top-h);
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.85;
  color: var(--paper);
  background-color: var(--arena);
  background-image:
    radial-gradient(circle at 84% -8%, rgba(47, 243, 208, 0.10), transparent 46%),
    radial-gradient(circle at 4% 106%, rgba(255, 138, 43, 0.08), transparent 44%),
    radial-gradient(rgba(122, 190, 255, 0.055) 1px, transparent 1px);
  background-size: auto, auto, 22px 22px;
  background-repeat: no-repeat, no-repeat, repeat;
}

#main-content { scroll-margin-top: calc(var(--top-h) + 24px); }

:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: rgba(47, 243, 208, 0.28);
  color: var(--paper);
}

/* ---------- 4. 工具类 ---------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: 8px;
  z-index: 200;
  padding: 10px 18px;
  border-radius: var(--radius-s);
  background: var(--neon);
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
  transform: translateY(-180%);
  transition: transform 0.2s var(--ease);
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding-inline: var(--pad-x);
}

.prose {
  max-width: 42rem;
  font-size: 16.5px;
  line-height: 1.85;
}

.prose p {
  margin-bottom: 1.1em;
  color: #cfdcee;
}

.prose p:last-child { margin-bottom: 0; }

.prose a {
  color: var(--neon);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 243, 208, 0.4);
}

.prose a:hover { color: var(--neon-soft); border-bottom-color: currentColor; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--neon);
}

.clock {
  font-family: var(--mono);
  font-weight: 700;
  font-size: clamp(3.5rem, 13vw, 9rem);
  line-height: 0.86;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  color: var(--paper);
}

.mono { font-family: var(--mono); font-variant-numeric: tabular-nums; }

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

.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 258px), 1fr)); }

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5em;
  min-height: 42px;
  padding: 0 18px;
  border-radius: var(--radius-s);
  border: 1px solid transparent;
  font-family: var(--sans);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.02em;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease),
              border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

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

.btn--primary {
  background: var(--ember);
  color: #1c0d02;
  box-shadow: 0 8px 24px rgba(255, 138, 43, 0.22);
}

.btn--primary:hover { background: #ffa254; }

.btn--ghost {
  background: var(--glass);
  border-color: var(--line);
  color: var(--paper);
}

.btn--ghost:hover {
  border-color: rgba(47, 243, 208, 0.55);
  color: var(--neon);
}

.btn--neon {
  background: var(--neon);
  color: var(--ink);
  box-shadow: 0 8px 24px rgba(47, 243, 208, 0.2);
}

.btn--neon:hover { background: var(--neon-soft); }

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

/* ---------- 6. 品牌标记 ---------- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  text-decoration: none;
  color: var(--paper);
}

.brand__mark {
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: linear-gradient(150deg, var(--neon), var(--neon-soft));
  color: var(--ink);
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  box-shadow: 0 0 0 1px rgba(47, 243, 208, 0.35), 0 6px 18px rgba(47, 243, 208, 0.18);
}

.brand__text {
  display: flex;
  flex-direction: column;
  min-width: 0;
  line-height: 1.18;
}

.brand__name {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.brand__line {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--mist);
}

/* ---------- 7. 头部：L 形框架 ---------- */
.site-header { position: relative; z-index: 70; }

.topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 80;
  display: flex;
  align-items: center;
  gap: clamp(10px, 2vw, 28px);
  height: var(--top-h);
  padding-inline: var(--pad-x);
  background: rgba(6, 18, 36, 0.86);
  backdrop-filter: blur(18px) saturate(140%);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  border-bottom: 1px solid var(--line);
  transition: background-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.topbar::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg, var(--neon), rgba(47, 243, 208, 0) 46%);
  pointer-events: none;
}

.site-header[data-scrolled] .topbar {
  background: rgba(6, 18, 36, 0.96);
  box-shadow: 0 12px 34px rgba(0, 0, 0, 0.36);
}

.topbar__status {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1 1 auto;
  min-width: 0;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.05em;
  color: var(--mist);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.status-dot {
  flex: 0 0 auto;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--neon);
  box-shadow: 0 0 0 3px rgba(47, 243, 208, 0.16);
  animation: status-pulse 2s ease-in-out infinite;
}

@keyframes status-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.35; }
}

.topbar__actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.topbar__progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  display: block;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--neon), var(--ember));
  box-shadow: 0 0 12px rgba(47, 243, 208, 0.45);
  pointer-events: none;
}

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  flex: 0 0 auto;
  margin-left: auto;
  padding: 8px 14px 8px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--glass);
  color: var(--paper);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.nav-toggle:hover { border-color: rgba(47, 243, 208, 0.5); }

.nav-toggle__bars {
  display: grid;
  gap: 4px;
  width: 16px;
}

.nav-toggle__bars i {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--neon);
  transition: transform 0.24s var(--ease), opacity 0.2s var(--ease);
}

.site-header[data-open] .nav-toggle__bars i:first-child { transform: translateY(3px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars i:last-child { transform: translateY(-3px) rotate(-45deg); }

/* 左侧竖栏 */
.sidenav {
  position: fixed;
  top: var(--top-h);
  left: 0;
  bottom: 0;
  z-index: 75;
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: min(84vw, var(--rail-w));
  padding: 22px 16px 26px;
  overflow-y: auto;
  overscroll-behavior: contain;
  background: linear-gradient(180deg, rgba(12, 32, 56, 0.96), rgba(6, 18, 36, 0.99));
  border-right: 1px solid var(--line);
  box-shadow: 26px 0 60px rgba(0, 0, 0, 0.42);
  transform: translateX(-104%);
  opacity: 0;
  visibility: hidden;
  transition: transform 0.28s var(--ease), opacity 0.28s var(--ease), visibility 0.28s;
}

.site-header[data-open] .sidenav {
  transform: none;
  opacity: 1;
  visibility: visible;
}

.sidenav__caption {
  padding: 0 10px 12px;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--mist);
}

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

.sidenav__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 11px 14px 11px 16px;
  border-left: 3px solid transparent;
  border-radius: 0 var(--radius-s) var(--radius-s) 0;
  color: var(--mist);
  font-size: 15px;
  text-decoration: none;
  transition: color 0.2s var(--ease), background-color 0.2s var(--ease),
              border-color 0.2s var(--ease);
}

.sidenav__index {
  flex: 0 0 auto;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: rgba(159, 179, 204, 0.62);
  transition: color 0.2s var(--ease);
}

.sidenav__label { min-width: 0; }

.sidenav__link:hover,
.sidenav__link:focus-visible {
  color: var(--paper);
  background: var(--glass);
  border-left-color: rgba(47, 243, 208, 0.5);
}

.sidenav__link:hover .sidenav__index { color: var(--neon); }

.sidenav__link[aria-current="page"] {
  color: var(--paper);
  background: linear-gradient(90deg, rgba(47, 243, 208, 0.16), rgba(47, 243, 208, 0));
  border-left-color: var(--neon);
  font-weight: 600;
}

.sidenav__link[aria-current="page"] .sidenav__index { color: var(--ember); }

.sidenav__foot {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 20px 10px 4px;
  border-top: 1px solid var(--line);
}

.sidenav__note {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

@media (min-width: 1024px) {
  body { padding-left: var(--rail-w); }

  .sidenav {
    width: var(--rail-w);
    padding: 34px 18px 30px;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    background: linear-gradient(180deg, rgba(12, 32, 56, 0.72), rgba(6, 18, 36, 0.9));
  }

  .site-header[data-scrolled] .sidenav {
    background: linear-gradient(180deg, rgba(12, 32, 56, 0.94), rgba(6, 18, 36, 0.99));
  }

  .sidenav__link { padding-inline: 18px 14px; }
}

@media (max-width: 1023px) {
  .nav-toggle { display: inline-flex; }
}

@media (max-width: 1100px) {
  .topbar__status { display: none; }
}

@media (max-width: 720px) {
  .topbar__actions .btn--ghost { display: none; }
  .brand__line { display: none; }
  .topbar__actions .btn { padding: 0 14px; font-size: 13px; }
}

@media (max-width: 400px) {
  .nav-toggle__label { display: none; }
  .nav-toggle { padding: 9px 12px; }
}

/* ---------- 8. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 9vw, 120px);
  background: linear-gradient(180deg, rgba(12, 32, 56, 0.46), rgba(6, 18, 36, 0.98) 34%);
  border-top: 1px solid var(--line);
}

.site-footer::before {
  content: '';
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--neon) 20%, var(--ember) 62%, transparent);
  opacity: 0.7;
  pointer-events: none;
}

.site-footer__inner {
  max-width: 1240px;
  margin-inline: auto;
  padding: clamp(40px, 6vw, 78px) var(--pad-x) 26px;
}

.footer-main {
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 2.2fr);
  align-items: start;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.footer-motto {
  max-width: 30ch;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--mist);
}

.footer-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.footer-nav {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
}

.footer-col__title {
  margin-bottom: 12px;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--neon);
}

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

.footer-col__list a {
  display: inline-flex;
  padding-block: 5px;
  font-size: 14.5px;
  color: var(--mist);
  text-decoration: none;
  transition: color 0.18s var(--ease), transform 0.18s var(--ease);
}

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

.footer-service {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr));
  margin-top: clamp(32px, 4vw, 54px);
  padding-top: clamp(24px, 3vw, 34px);
  border-top: 1px solid var(--line);
}

.service-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.service-list li {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  font-size: 14px;
}

.service-list__key {
  flex: 0 0 auto;
  min-width: 5.2em;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--mist);
  padding-top: 2px;
}

.service-list__val {
  color: var(--paper);
  font-family: var(--mono);
  font-size: 13.5px;
  word-break: break-all;
}

.service-note {
  max-width: 46ch;
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--mist);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 24px;
  margin-top: clamp(28px, 4vw, 44px);
  padding-top: 22px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--mist);
}

.legal-copy { font-family: var(--mono); letter-spacing: 0.03em; }

.legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin-left: auto;
}

.legal-links a {
  color: var(--mist);
  text-decoration: none;
  transition: color 0.18s var(--ease);
}

.legal-links a:hover { color: var(--neon); }

.legal-icp {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: rgba(159, 179, 204, 0.72);
  width: 100%;
}

@media (min-width: 1024px) {
  .legal-icp { width: auto; }
}

@media (max-width: 900px) {
  .footer-main { grid-template-columns: 1fr; }
  .legal-links { margin-left: 0; }
}

/* ---------- 9. 通用内容组件 ---------- */
/* 玻璃层 */
.glass {
  background: var(--glass);
  border: 1px solid var(--glass-line);
  border-radius: var(--radius-m);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
}

/* 实色内容层 */
.card-solid {
  padding: clamp(18px, 2.6vw, 28px);
  background: var(--night);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
}

/* 章节色带 */
.section-band {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px 18px;
  min-height: 58px;
  padding: 12px 20px;
  margin-bottom: clamp(24px, 3.5vw, 40px);
  background: linear-gradient(90deg, rgba(47, 243, 208, 0.13), rgba(12, 32, 56, 0.5) 56%, rgba(6, 18, 36, 0));
  border-left: 3px solid var(--neon);
  border-radius: 0 var(--radius-s) var(--radius-s) 0;
}

.section-band__index {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--neon);
}

.section-band__meta {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist);
}

/* 斜切过渡带 */
.cut-band {
  height: clamp(28px, 5vw, 58px);
  margin-block: clamp(28px, 5vw, 60px);
  background: linear-gradient(90deg, rgba(47, 243, 208, 0.12), rgba(255, 138, 43, 0.08) 70%, transparent);
  clip-path: polygon(0 0, 100% 22%, 100% 100%, 0 78%);
}

/* 高密度索引网格 */
.index-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 268px), 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.index-cell {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(18px, 2.4vw, 24px);
  background: var(--night);
  color: inherit;
  text-decoration: none;
  transition: background-color 0.22s var(--ease);
}

a.index-cell:hover { background: #12294a; }

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  align-self: flex-start;
  padding: 4px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--mist);
}

.tag--neon {
  color: var(--neon);
  border-color: rgba(47, 243, 208, 0.42);
  background: rgba(47, 243, 208, 0.08);
}

.tag--amber {
  color: var(--amber);
  border-color: rgba(255, 194, 75, 0.42);
  background: rgba(255, 194, 75, 0.09);
}

.tag--live {
  color: #1c0d02;
  background: var(--ember);
  border-color: transparent;
}

/* 纵向时间轴 */
.rail {
  position: relative;
  padding-left: 30px;
}

.rail::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--line);
}

.rail__item {
  position: relative;
  padding-block: 12px;
}

.rail__item::before {
  content: '';
  position: absolute;
  left: -30px;
  top: 18px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: var(--arena);
  transition: border-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.rail__item[data-live]::before,
.rail__item:hover::before {
  border-color: var(--neon);
  box-shadow: 0 0 0 4px rgba(47, 243, 208, 0.14);
}

/* 折叠组 */
.accordion {
  border-radius: var(--radius-s);
  overflow: hidden;
}

.accordion__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-s);
  background: var(--night);
  color: var(--paper);
  font-size: 15px;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.accordion__trigger:hover { border-color: rgba(47, 243, 208, 0.5); }

.accordion__trigger[aria-expanded="true"] {
  border-color: var(--neon);
  background: rgba(47, 243, 208, 0.06);
  border-bottom-left-radius: 0;
  border-bottom-right-radius: 0;
}

.accordion__trigger::after {
  content: '';
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg) translate(-2px, -2px);
  transition: transform 0.24s var(--ease);
}

.accordion__trigger[aria-expanded="true"]::after {
  transform: rotate(-135deg) translate(-2px, -2px);
}

.accordion__panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.24s var(--ease);
}

.accordion__panel[data-open] { grid-template-rows: 1fr; }

.accordion__inner {
  overflow: hidden;
  opacity: 0;
  transition: opacity 0.24s var(--ease);
}

.accordion__panel[data-open] .accordion__inner { opacity: 1; }

/* 图片容器 */
.img-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: linear-gradient(150deg, rgba(47, 243, 208, 0.10), rgba(12, 32, 56, 0.55) 48%, rgba(255, 138, 43, 0.10));
  isolation: isolate;
}

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

.img-frame--wide { aspect-ratio: 16 / 9; }
.img-frame--tall { aspect-ratio: 3 / 4; }
.img-frame--square { aspect-ratio: 1 / 1; }

.img-frame--cut {
  clip-path: polygon(0 0, 100% 0, 100% 90%, 0 100%);
  border-radius: var(--radius-m) var(--radius-m) 0 0;
}

.img-frame__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 30px 16px 12px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--paper);
  background: linear-gradient(transparent, rgba(4, 12, 24, 0.9));
}

/* 面包屑 */
.breadcrumb {
  padding-block: 6px;
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb li + li::before {
  content: '/';
  color: var(--line);
}

.breadcrumb a {
  color: var(--mist);
  text-decoration: none;
  transition: color 0.18s var(--ease);
}

.breadcrumb a:hover { color: var(--neon); }

.breadcrumb [aria-current="page"] { color: var(--paper); }

/* ---------- 10. 动效协议 ---------- */
[data-reveal] { opacity: 1; transform: none; }

html.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
}

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

@media (prefers-reduced-motion: reduce) {
  html.js [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}