/* ============================================================
   华体汇体育 · 全站共享样式 /assets/site.css
   色彩：深墨绿 · 炭黑 · 深青灰 · 苔绿 · 岩灰 · 冷灰绿 · 米白
        荧光青柠 · 暖橙 · 陶土
   ============================================================ */

/* ---------- reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--top-h) + 16px);
}

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

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

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

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

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

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

/* ---------- tokens ---------- */
:root {
  --ink: #081C15;
  --carbon: #111714;
  --slate: #1A2B27;
  --moss: #2F4A3B;
  --stone: #738079;
  --mist: #A7B3AA;
  --bone: #F4EFE2;
  --lime: #C9FF4A;
  --orange: #FF8A3D;
  --clay: #B96A4C;

  --rail-w: 104px;
  --top-h: 72px;
  --quick-h: 64px;

  --shell: 1440px;
  --gutter: clamp(20px, 4vw, 56px);

  --line: rgba(167, 179, 170, 0.18);
  --line-strong: rgba(167, 179, 170, 0.36);

  --font-display: "HarmonyOS Sans SC Condensed", "Alibaba PuHuiTi 3.0 85S",
    "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei",
    system-ui, -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", "JetBrains Mono", ui-monospace,
    SFMono-Regular, Menlo, Consolas, monospace;

  --dur: 200ms;
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
  --radius: 14px;
}

/* ---------- base ---------- */
body {
  min-height: 100vh;
  padding-left: var(--rail-w);
  background-color: var(--ink);
  background-image:
    linear-gradient(90deg, rgba(167, 179, 170, 0.045) 1px, transparent 1px),
    linear-gradient(180deg, rgba(167, 179, 170, 0.045) 1px, transparent 1px);
  background-size: 96px 96px;
  background-attachment: fixed;
  color: var(--bone);
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--bone);
}

h1 { font-size: clamp(2.4rem, 5.4vw, 5.2rem); }
h2 { font-size: clamp(1.6rem, 3vw, 2.6rem); }
h3 { font-size: clamp(1.15rem, 1.8vw, 1.5rem); letter-spacing: 0; }

p { max-width: 68ch; }

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

::selection {
  background: var(--lime);
  color: var(--carbon);
}

:focus-visible {
  outline: 2px solid var(--lime);
  outline-offset: 2px;
  box-shadow: 0 0 0 4px rgba(8, 28, 21, 0.92);
  border-radius: 3px;
}

#main-content {
  display: block;
  padding-top: var(--top-h);
}

/* ---------- layout helpers ---------- */
.shell {
  width: min(100% - var(--gutter) * 2, var(--shell));
  margin-inline: auto;
}

.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 28px);
}
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-7-5 { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }

.divider {
  height: 1px;
  border: 0;
  background: var(--line);
  margin-block: clamp(28px, 4.5vw, 52px);
}

.visually-hidden {
  position: absolute !important;
  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 ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: 16px;
  z-index: 300;
  padding: 0.7em 1.2em;
  background: var(--lime);
  color: var(--carbon);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: 0 0 8px 8px;
  transition: top 180ms var(--ease);
}
.skip-link:focus-visible {
  top: 0;
  outline-offset: 4px;
}

/* ---------- header shell ---------- */
.site-header {
  position: fixed;
  inset: 0;
  z-index: 90;
  pointer-events: none;
}

.read-progress {
  position: fixed;
  top: 0;
  left: var(--rail-w);
  right: 0;
  height: 2px;
  z-index: 120;
  pointer-events: none;
  background: rgba(167, 179, 170, 0.12);
}
.read-progress-bar {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--lime), var(--orange));
  will-change: transform;
}

/* ---------- 左侧品牌轨道 ---------- */
.brand-rail {
  position: fixed;
  inset: 0 auto 0 0;
  width: var(--rail-w);
  z-index: 92;
  pointer-events: auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  padding: 20px 8px 18px;
  background-color: var(--carbon);
  background-image: linear-gradient(180deg, rgba(201, 255, 74, 0.1), transparent 46%);
  border-right: 1px solid var(--line);
}

.rail-brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}

.rail-mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  background: var(--lime);
  color: var(--carbon);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 20px;
  border-radius: 14px 4px 14px 4px;
  transition: border-radius var(--dur) var(--ease), background var(--dur) var(--ease);
}
.rail-brand:hover .rail-mark,
.rail-brand:focus-visible .rail-mark {
  border-radius: 4px 14px 4px 14px;
  background: var(--orange);
}

.rail-word {
  writing-mode: vertical-rl;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.26em;
  color: var(--bone);
}

.rail-tagline {
  writing-mode: vertical-rl;
  font-size: 10px;
  letter-spacing: 0.34em;
  color: var(--stone);
}

.rail-nav {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  width: 100%;
  margin-top: auto;
  margin-bottom: auto;
}

.rail-link {
  position: relative;
  display: grid;
  place-items: center;
  width: 34px;
  height: 32px;
  border-radius: 8px;
  border: 1px solid transparent;
  color: var(--mist);
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}
.rail-link:hover {
  color: var(--bone);
  border-color: var(--line-strong);
  background: rgba(47, 74, 59, 0.5);
}
.rail-link[aria-current="page"] {
  background: var(--lime);
  border-color: var(--lime);
  color: var(--carbon);
}

.rail-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.02em;
  font-variant-numeric: tabular-nums;
}

.rail-name {
  position: absolute;
  left: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%) translateX(-6px);
  white-space: nowrap;
  padding: 4px 10px;
  background: var(--slate);
  border: 1px solid var(--line-strong);
  border-radius: 4px;
  color: var(--bone);
  font-size: 12px;
  letter-spacing: 0.08em;
  opacity: 0;
  pointer-events: none;
  transition: opacity 160ms var(--ease), transform 160ms var(--ease);
  z-index: 96;
}
.rail-link:hover .rail-name,
.rail-link:focus-visible .rail-name {
  opacity: 1;
  transform: translateY(-50%) translateX(0);
}

.rail-foot {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.28em;
  color: var(--stone);
  opacity: 0.75;
}

/* ---------- 顶部条 ---------- */
.top-bar {
  position: fixed;
  top: 0;
  left: var(--rail-w);
  right: 0;
  height: var(--top-h);
  z-index: 91;
  pointer-events: auto;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 18px;
  padding: 0 var(--gutter);
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background 240ms var(--ease), border-color 240ms var(--ease);
}
.site-header[data-scrolled="true"] .top-bar {
  background: rgba(8, 28, 21, 0.94);
  border-bottom-color: var(--line);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
}

/* 移动端品牌条（桌面隐藏） */
.brand-mini {
  display: none;
  align-items: center;
  gap: 10px;
  margin-right: auto;
}
.brand-mini-mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  background: var(--lime);
  color: var(--carbon);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 16px;
  border-radius: 10px 3px 10px 3px;
}
.brand-mini-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}
.brand-mini-text strong {
  font-size: 0.94rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--bone);
}
.brand-mini-text em {
  font-style: normal;
  font-size: 0.6rem;
  letter-spacing: 0.3em;
  color: var(--stone);
}

/* 移动端菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 14px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--bone);
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.nav-toggle:hover,
.nav-toggle:focus-visible {
  border-color: var(--lime);
  color: var(--lime);
}
.nav-toggle-bars {
  display: inline-flex;
  flex-direction: column;
  gap: 4px;
  width: 16px;
}
.nav-toggle-bars i {
  display: block;
  height: 1.5px;
  background: currentColor;
  border-radius: 2px;
  transition: transform var(--dur) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:first-child {
  transform: translateY(2.75px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:last-child {
  transform: translateY(-2.75px) rotate(-45deg);
}

/* ---------- 主导航（桌面横向） ---------- */
.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2vw, 30px);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: clamp(12px, 1.8vw, 26px);
  counter-reset: nav;
}
.nav-list li { counter-increment: nav; }

.nav-list a {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  padding: 6px 2px;
  font-size: 0.86rem;
  letter-spacing: 0.05em;
  color: var(--mist);
  transition: color var(--dur) var(--ease);
}
.nav-list a::before {
  content: counter(nav, decimal-leading-zero);
  margin-right: 0.5em;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0;
  color: var(--stone);
  transition: color var(--dur) var(--ease);
}
.nav-list a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--lime);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur) var(--ease);
}
.nav-list a:hover { color: var(--bone); }
.nav-list a:hover::before { color: var(--lime); }
.nav-list a:hover::after { transform: scaleX(1); }
.nav-list a[aria-current="page"] { color: var(--lime); }
.nav-list a[aria-current="page"]::before { color: var(--lime); }
.nav-list a[aria-current="page"]::after { transform: scaleX(1); }

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5em;
  padding: 0.62em 1.15em;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: var(--font-body);
  font-size: 0.84rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  line-height: 1.4;
  white-space: nowrap;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease),
    background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.btn:active { transform: translateY(1px); }

.btn-signal {
  color: var(--carbon);
  background-color: var(--lime);
  background-image: linear-gradient(90deg, var(--bone), var(--bone));
  background-repeat: no-repeat;
  background-position: 0 0;
  background-size: 0% 100%;
  transition: background-size 260ms var(--ease), color var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}
.btn-signal:hover,
.btn-signal:focus-visible {
  background-size: 100% 100%;
  color: var(--carbon);
}

.btn-ghost {
  color: var(--bone);
  border-color: var(--line-strong);
  background-color: transparent;
}
.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--lime);
  color: var(--lime);
  background-color: rgba(201, 255, 74, 0.08);
}

/* ---------- 移动端底部快捷条 ---------- */
.quick-bar {
  display: none;
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  height: var(--quick-h);
  z-index: 95;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  background: var(--carbon);
  border-top: 1px solid var(--line-strong);
  padding-bottom: env(safe-area-inset-bottom);
}
.quick-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  border-right: 1px solid var(--line);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--mist);
  transition: color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.quick-link:last-child { border-right: 0; }
.quick-link span {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.16em;
  color: var(--stone);
  transition: color var(--dur) var(--ease);
}
.quick-link:hover,
.quick-link:focus-visible {
  color: var(--bone);
  background: rgba(201, 255, 74, 0.08);
}
.quick-link:hover span { color: var(--lime); }
.quick-link[aria-current="page"] { color: var(--lime); }
.quick-link[aria-current="page"] span { color: var(--lime); }

/* ---------- 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 110px);
  background: var(--carbon);
  border-top: 1px solid var(--line-strong);
  color: var(--mist);
  overflow: hidden;
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--lime) 22%, var(--orange) 78%, transparent);
  opacity: 0.55;
}
.site-footer .shell {
  padding-block: clamp(44px, 6vw, 76px) 26px;
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.9fr);
  gap: clamp(30px, 5vw, 72px);
}

.footer-logo {
  display: inline-block;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.5rem, 2.6vw, 2.05rem);
  letter-spacing: 0.02em;
  color: var(--bone);
  transition: color var(--dur) var(--ease);
}
.footer-logo:hover { color: var(--lime); }

.footer-tagline {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.28em;
  color: var(--lime);
}

.footer-summary {
  margin-top: 18px;
  max-width: 36ch;
  font-size: 0.93rem;
  line-height: 1.78;
  color: var(--mist);
}

.footer-cta { margin-top: 22px; }

.footer-nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}

.footer-col-title {
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.22em;
  color: var(--stone);
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 11px;
}
.footer-col a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.92rem;
  color: var(--mist);
  transition: color var(--dur) var(--ease);
}
.footer-col a::before {
  content: "";
  width: 14px;
  height: 1px;
  background: var(--stone);
  transition: width var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.footer-col a:hover,
.footer-col a:focus-visible { color: var(--lime); }
.footer-col a:hover::before,
.footer-col a:focus-visible::before {
  width: 24px;
  background: var(--lime);
}

.footer-contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 16px 32px;
  margin-top: clamp(32px, 5vw, 56px);
  padding-top: 26px;
  border-top: 1px solid var(--line);
}
.contact-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  max-width: none;
}
.contact-key {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--stone);
}
.contact-val {
  font-size: 0.9rem;
  letter-spacing: 0.01em;
  color: var(--bone);
  word-break: break-word;
}

.footer-note {
  margin-top: 18px;
  max-width: 60ch;
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--stone);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 22px;
  margin-top: clamp(24px, 4vw, 40px);
  padding-top: 20px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--stone);
}
.footer-base-link {
  color: var(--mist);
  transition: color var(--dur) var(--ease);
}
.footer-base-link:hover,
.footer-base-link:focus-visible { color: var(--lime); }
.footer-sign {
  margin-left: auto;
  color: var(--stone);
  opacity: 0.7;
  letter-spacing: 0.16em;
}

/* ---------- 面包屑 ---------- */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 18px 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--stone);
}
.breadcrumbs li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.breadcrumbs li:not(:last-child)::after {
  content: "/";
  color: var(--stone);
  opacity: 0.6;
}
.breadcrumbs a {
  color: var(--mist);
  transition: color var(--dur) var(--ease);
}
.breadcrumbs a:hover,
.breadcrumbs a:focus-visible { color: var(--lime); }
.breadcrumbs [aria-current="page"] { color: var(--bone); }

/* ---------- 正文 ---------- */
.prose {
  max-width: 66ch;
  font-size: 1.02rem;
  line-height: 1.78;
  color: var(--mist);
}
.prose h2,
.prose h3 {
  margin-top: 1.8em;
  margin-bottom: 0.6em;
  color: var(--bone);
}
.prose p + p { margin-top: 1.05em; }
.prose ul,
.prose ol {
  margin-top: 1em;
  padding-left: 1.1em;
  list-style: none;
}
.prose ul li,
.prose ol li {
  position: relative;
  padding-left: 1.1em;
  margin-top: 0.5em;
}
.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.85em;
  width: 12px;
  height: 1px;
  background: var(--lime);
}
.prose ol { counter-reset: prose-ol; }
.prose ol li {
  counter-increment: prose-ol;
  padding-left: 2em;
}
.prose ol li::before {
  content: counter(prose-ol, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0.1em;
  font-family: var(--font-mono);
  font-size: 0.78em;
  color: var(--lime);
}
.prose strong { color: var(--bone); }
.prose a {
  color: var(--lime);
  border-bottom: 1px solid rgba(201, 255, 74, 0.4);
  transition: border-color var(--dur) var(--ease);
}
.prose a:hover { border-color: var(--lime); }

/* ---------- 章节头 ---------- */
.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: 10px 24px;
  margin-bottom: clamp(20px, 3vw, 36px);
}
.section-num {
  display: inline-flex;
  align-items: center;
  padding: 2px 9px;
  border: 1px solid rgba(201, 255, 74, 0.55);
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.16em;
  color: var(--lime);
  font-variant-numeric: tabular-nums;
}
.section-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.5rem, 2.8vw, 2.3rem);
  line-height: 1.14;
  letter-spacing: -0.01em;
  color: var(--bone);
}
.section-dek {
  flex-basis: 100%;
  max-width: 54ch;
  font-size: 0.95rem;
  line-height: 1.72;
  color: var(--mist);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--stone);
}
.eyebrow::before {
  content: "";
  width: 18px;
  height: 1px;
  background: var(--lime);
}

/* ---------- 卡片 ---------- */
.card {
  position: relative;
  padding: clamp(18px, 2.4vw, 28px);
  background: var(--slate);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease),
    background-color var(--dur) var(--ease);
}
.card:hover,
.card:focus-within {
  transform: translateY(-3px);
  border-color: rgba(201, 255, 74, 0.42);
  background: var(--moss);
}

.card-reveal {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  margin-top: 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--bone);
  transition: max-height 240ms var(--ease), opacity 240ms var(--ease),
    margin-top 240ms var(--ease);
}
.card:hover .card-reveal,
.card:focus-within .card-reveal {
  max-height: 14rem;
  opacity: 1;
  margin-top: 12px;
}

/* ---------- 图片容器 ---------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--line);
  border-radius: 16px;
  background-color: var(--slate);
  background-image: linear-gradient(135deg, rgba(47, 74, 59, 0.7), rgba(8, 28, 21, 0.9));
}
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 46%;
  background: linear-gradient(180deg, transparent, rgba(8, 28, 21, 0.88));
  pointer-events: none;
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--portrait { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame-caption {
  position: absolute;
  left: 14px;
  bottom: 12px;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--bone);
}

/* ---------- 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--mist);
  white-space: nowrap;
}
.tag--lime {
  border-color: rgba(201, 255, 74, 0.5);
  color: var(--lime);
}
.tag--orange {
  border-color: rgba(255, 138, 61, 0.5);
  color: var(--orange);
}

/* ---------- 数据指标 ---------- */
.stat {
  display: flex;
  flex-direction: column;
  gap: 5px;
}
.stat-value {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(1.6rem, 3vw, 2.6rem);
  line-height: 1;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
  color: var(--bone);
}
.stat-label {
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  color: var(--stone);
}

/* ---------- 注释 ---------- */
.note {
  max-width: 60ch;
  font-size: 0.78rem;
  line-height: 1.65;
  letter-spacing: 0.02em;
  color: var(--stone);
}

/* ---------- 响应式：平板与手机 ---------- */
@media (max-width: 1180px) {
  .nav-list { gap: 14px; }
  .nav-list a::before { display: none; }
  .nav-list a { font-size: 0.82rem; }
}

@media (max-width: 1023px) {
  :root {
    --top-h: 64px;
    --rail-w: 0px;
  }

  body {
    padding-left: 0;
    background-attachment: scroll;
  }

  #main-content { padding-top: var(--top-h); }

  .read-progress { left: 0; }

  .brand-rail { display: none; }

  .top-bar {
    left: 0;
    justify-content: space-between;
    background: var(--carbon);
    border-bottom-color: var(--line);
  }
  .site-header[data-scrolled="true"] .top-bar {
    background: var(--carbon);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }

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

  .site-nav {
    position: fixed;
    top: var(--top-h);
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 94;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 20px var(--gutter) calc(var(--quick-h) + 32px);
    background: var(--carbon);
    border-top: 1px solid var(--line);
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 200ms var(--ease), transform 200ms var(--ease),
      visibility 200ms linear;
  }
  .site-nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    counter-reset: nav;
  }
  .nav-list a {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 15px 0;
    font-size: 1.05rem;
    letter-spacing: 0.04em;
    color: var(--bone);
    border-bottom: 1px solid var(--line);
  }
  .nav-list a::before {
    display: inline-block;
    font-size: 0.7rem;
    color: var(--stone);
    margin-right: 0;
  }
  .nav-list a::after { display: none; }
  .nav-list a[aria-current="page"] { color: var(--lime); }

  .nav-actions {
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    margin-top: 22px;
  }
  .nav-actions .btn {
    width: 100%;
    padding: 0.95em 1.2em;
    font-size: 0.92rem;
  }

  .quick-bar { display: grid; }

  .site-footer .shell {
    padding-bottom: calc(var(--quick-h) + 32px);
  }

  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-sign { margin-left: 0; flex-basis: 100%; }

  .skip-link { left: 12px; }
}

@media (max-width: 900px) {
  .grid-2,
  .grid-3,
  .grid-7-5 { grid-template-columns: minmax(0, 1fr); }

  .section-head { gap: 8px 16px; }
}

@media (max-width: 560px) {
  .footer-nav { grid-template-columns: minmax(0, 1fr); }
  .footer-contact { grid-template-columns: minmax(0, 1fr); }
  .nav-toggle-text { display: none; }
  .nav-toggle { padding: 9px 12px; }
}

@media (max-height: 720px) and (min-width: 1024px) {
  .rail-foot { display: none; }
  .rail-tagline { display: none; }
  .rail-nav { gap: 4px; }
  .rail-link { height: 28px; }
}

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

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

  .card:hover,
  .card:focus-within { transform: none; }

  .btn:active { transform: none; }

  .card-reveal { max-height: none; }
  .card:hover .card-reveal,
  .card:focus-within .card-reveal { max-height: none; }
}