/* ============================================================
   半岛赛场 / PENINSULA ARENA  —  /assets/site.css
   共享外壳：reset / 变量 / 排版 / 头部轨道 / 页脚 / 基础组件
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--topbar) + 18px);
}

body {
  margin: 0;
  background: #071523;
  color: #F7F1E6;
  font-family: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  font-size: 16px;
  line-height: 1.65;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  padding-left: var(--rail);
  min-height: 100vh;
}

img, svg, picture, video { display: block; max-width: 100%; }
button { font: inherit; }
ul, ol { margin: 0; padding: 0; }
a { color: inherit; }

:focus-visible {
  outline: 2px solid #3AF2C4;
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 2. 变量 ---------- */
:root {
  /* 色彩 */
  --deep: #071523;
  --ink2: #0D2137;
  --tactic: #16324F;
  --sand: #D9B46A;
  --sandpale: #F2E3BE;
  --paper: #F7F1E6;
  --mint: #3AF2C4;
  --mintdark: #1C9B82;
  --coral: #FF6F4E;
  --coraldark: #B84B36;
  --mist: #8FA6BD;
  --steel: #2B4058;
  --night: #030A12;

  /* 字体 */
  --font-head: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-data: 'JetBrains Mono', 'Roboto Mono', ui-monospace, monospace;

  /* 尺寸 */
  --rail: 108px;
  --topbar: 62px;
  --maxw: 1280px;
  --gap: clamp(16px, 2.4vw, 28px);
}

@media (min-width: 900px) {
  html { scroll-padding-top: 34px; }
}

/* ---------- 3. 中文排版基线 ---------- */
h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 900;
  letter-spacing: 0.05em;
  line-height: 1.14;
  color: var(--paper);
  margin: 0 0 0.62em;
}

h1 { font-size: clamp(2.2rem, 5vw, 4.2rem); }
h2 { font-size: clamp(1.6rem, 3.2vw, 2.5rem); }
h3 { font-size: clamp(1.1rem, 1.7vw, 1.35rem); letter-spacing: 0.06em; }
h4 { font-size: 1rem; letter-spacing: 0.1em; }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

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

::selection { background: var(--sand); color: #08131F; }

/* ---------- 4. 布局工具 ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: clamp(18px, 4vw, 56px);
}

.section { padding-block: clamp(44px, 6.5vw, 92px); }

.grid { display: grid; gap: var(--gap); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--auto { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

.rule {
  height: 1px;
  border: 0;
  margin-block: clamp(28px, 4.5vw, 60px);
  background: linear-gradient(90deg, var(--steel) 0%, rgba(43, 64, 88, 0) 100%);
}

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 0.9em;
  font-family: var(--font-data);
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--sand);
}
.eyebrow::before {
  content: "";
  display: block;
  width: 26px;
  height: 2px;
  background: var(--sand);
}

.notice {
  background: var(--sandpale);
  color: #0B1B2A;
  padding: clamp(14px, 2vw, 22px);
  border-radius: 2px;
  font-weight: 500;
  line-height: 1.68;
}
.notice a { color: #8A3A22; text-decoration: underline; }

.prose {
  max-width: 68ch;
  font-size: 1.02rem;
  line-height: 1.78;
  color: #DCE4EC;
}
.prose h2 { margin-top: 1.9em; }
.prose h3 { margin-top: 1.6em; color: var(--sandpale); }
.prose ul, .prose ol { padding-left: 1.25em; margin-bottom: 1em; }
.prose li { margin-bottom: 0.45em; }
.prose a { color: var(--mint); text-decoration: none; border-bottom: 1px solid rgba(58, 242, 196, 0.35); }
.prose a:hover { border-color: var(--mint); }
.prose blockquote {
  margin: 1.6em 0;
  padding: 14px 18px;
  border-left: 2px solid var(--sand);
  background: rgba(13, 33, 55, 0.72);
  color: var(--sandpale);
}

/* ---------- 5. Skip link ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 400;
  transform: translateY(-180%);
  background: var(--sand);
  color: #08131F;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.86rem;
  letter-spacing: 0.1em;
  padding: 0.72em 1.2em;
  border-radius: 2px;
  text-decoration: none;
  transition: transform 0.18s ease;
}
.skip-link:focus { transform: translateY(0); }

#main-content:focus { outline: none; }

/* ---------- 6. 头部：侧边轨道 ---------- */
.site-header {
  position: fixed;
  inset: 0 auto 0 0;
  width: var(--rail);
  z-index: 120;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  padding: 20px 0 18px;
  background: linear-gradient(180deg, #0D2137 0%, #071523 54%, #0A1A2A 100%);
  border-right: 1px solid var(--steel);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: none;
}
.site-header::-webkit-scrollbar { display: none; }

/* 滚动进度 */
.scroll-progress {
  position: absolute;
  top: 0;
  right: -1px;
  width: 2px;
  height: 100%;
  background: linear-gradient(180deg, var(--sand) 0%, var(--coral) 55%, var(--mint) 100%);
  transform: scaleY(var(--progress, 0));
  transform-origin: top center;
  transition: transform 0.12s linear;
  pointer-events: none;
}

/* 品牌脊标 */
.brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  padding: 0 10px;
  text-decoration: none;
  color: var(--paper);
}
.brand__rule {
  display: block;
  width: 2px;
  height: 28px;
  background: linear-gradient(180deg, var(--sand) 0%, rgba(217, 180, 106, 0) 100%);
}
.brand__cn {
  writing-mode: vertical-rl;
  text-orientation: upright;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 0.95rem;
  letter-spacing: 0.26em;
  line-height: 1.05;
  color: var(--paper);
  transition: color 0.2s ease;
}
.brand__en {
  writing-mode: vertical-rl;
  text-orientation: upright;
  font-family: var(--font-data);
  font-size: 0.5rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  line-height: 1.2;
  color: var(--mist);
}
.brand:hover .brand__cn { color: var(--sand); }

/* 移动按钮（桌面隐藏） */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  background: transparent;
  border: 1px solid var(--steel);
  border-radius: 2px;
  color: var(--paper);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease;
}
.nav-toggle:hover { border-color: var(--sand); color: var(--sand); }
.nav-toggle__bars { display: grid; gap: 4px; width: 18px; }
.nav-toggle__bars span {
  display: block;
  height: 2px;
  background: var(--sand);
  transition: transform 0.26s ease, opacity 0.2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* 导航主体 */
.site-nav {
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  margin-top: 22px;
}

.nav-kicker {
  margin: 0 0 8px;
  padding: 0 10px;
  font-family: var(--font-data);
  font-size: 0.52rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-align: center;
  color: #4A678A;
  text-transform: uppercase;
}

.nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 0 8px;
}

.nav-link {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
  padding: 9px 4px;
  text-decoration: none;
  color: var(--mist);
  border-radius: 2px;
  transition: color 0.2s ease, background 0.2s ease;
}
.nav-link__num {
  font-family: var(--font-data);
  font-size: 0.54rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: #4A678A;
  transition: color 0.2s ease;
}
.nav-link__label {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  white-space: nowrap;
  line-height: 1.2;
}
.nav-link:hover { color: var(--paper); background: rgba(22, 50, 79, 0.55); }
.nav-link:hover .nav-link__num { color: var(--sand); }

.nav-link[aria-current="page"] {
  color: var(--sand);
  background: rgba(217, 180, 106, 0.09);
}
.nav-link[aria-current="page"] .nav-link__num { color: var(--sand); }
.nav-link[aria-current="page"]::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 50%;
  transform: translateY(-50%);
  width: 2px;
  height: 22px;
  background: var(--sand);
}

/* 快捷入口 */
.nav-shortcuts {
  margin-top: 20px;
  padding: 16px 8px 0;
  border-top: 1px solid var(--steel);
}
.shortcut-list {
  list-style: none;
  display: grid;
  gap: 6px;
}
.shortcut {
  display: block;
  padding: 8px 4px;
  text-align: center;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.64rem;
  letter-spacing: 0.1em;
  line-height: 1.3;
  text-decoration: none;
  color: var(--sandpale);
  background: var(--tactic);
  border: 1px solid rgba(43, 64, 88, 0.9);
  border-radius: 2px;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.shortcut:hover {
  background: var(--sand);
  border-color: var(--sand);
  color: #08131F;
}

/* 轨道状态 */
.rail-status {
  margin-top: auto;
  padding: 20px 8px 0;
  display: grid;
  gap: 8px;
  border-top: 1px solid rgba(43, 64, 88, 0.65);
  margin-top: 22px;
}
.rail-status__item {
  display: flex;
  align-items: center;
  gap: 6px;
  margin: 0;
  font-family: var(--font-data);
  font-size: 0.55rem;
  letter-spacing: 0.04em;
  line-height: 1.4;
  color: var(--mist);
}
.dot {
  flex: 0 0 auto;
  width: 5px;
  height: 5px;
  border-radius: 50%;
}
.dot--mint { background: var(--mint); box-shadow: 0 0 8px rgba(58, 242, 196, 0.7); }
.dot--sand { background: var(--sand); }

/* ---------- 7. 页脚 ---------- */
.site-footer {
  position: relative;
  background: var(--ink2);
  border-top: 1px solid var(--steel);
  padding-block: clamp(38px, 6vw, 74px) 26px;
}
.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  height: 2px;
  width: min(42%, 360px);
  background: linear-gradient(90deg, var(--sand) 0%, var(--coral) 58%, rgba(255, 111, 78, 0) 100%);
  pointer-events: none;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, minmax(0, 1fr));
  gap: clamp(22px, 3.4vw, 46px);
  align-items: start;
}

.footer-logo {
  display: inline-block;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1.35rem;
  letter-spacing: 0.16em;
  color: var(--paper);
  text-decoration: none;
  transition: color 0.2s ease;
}
.footer-logo:hover { color: var(--sand); }
.footer-logo__en {
  margin: 0.55em 0 1em;
  font-family: var(--font-data);
  font-size: 0.6rem;
  font-weight: 600;
  letter-spacing: 0.32em;
  color: var(--sand);
}
.footer-tagline {
  max-width: 24ch;
  font-size: 0.86rem;
  line-height: 1.75;
  color: var(--mist);
}
.footer-domain {
  margin: 1em 0 0;
  font-family: var(--font-data);
  font-size: 0.64rem;
  letter-spacing: 0.16em;
  color: #4E6B87;
}

.footer-col__title {
  margin: 0 0 1.1em;
  font-family: var(--font-head);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.26em;
  color: var(--sand);
  text-transform: uppercase;
}
.footer-links { list-style: none; display: grid; gap: 0.62em; }
.footer-links a {
  display: inline-block;
  font-size: 0.9rem;
  letter-spacing: 0.04em;
  color: #C6D4E2;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, transform 0.18s ease, border-color 0.18s ease;
}
.footer-links a:hover {
  color: var(--mint);
  transform: translateX(3px);
  border-bottom-color: rgba(58, 242, 196, 0.5);
}

.footer-contact {
  margin-top: clamp(28px, 4vw, 50px);
  padding-top: clamp(20px, 3vw, 30px);
  border-top: 1px solid var(--steel);
  display: grid;
  gap: 10px;
}
.footer-contact__label {
  margin: 0;
  font-family: var(--font-data);
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.26em;
  color: var(--sand);
}
.footer-contact__list { list-style: none; display: grid; gap: 9px; }
.footer-contact__list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.4em 1em;
  font-size: 0.88rem;
  color: #C6D4E2;
}
.footer-contact__key {
  min-width: 3.2em;
  font-family: var(--font-data);
  font-size: 0.64rem;
  letter-spacing: 0.16em;
  color: var(--mist);
}
.footer-contact__val { word-break: break-word; }
.footer-contact__note {
  margin: 0.2em 0 0;
  font-size: 0.76rem;
  line-height: 1.7;
  color: var(--mist);
}

.copy-btn {
  padding: 0 0 2px;
  background: transparent;
  border: 0;
  border-bottom: 1px dashed var(--steel);
  color: var(--mist);
  font: inherit;
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: color 0.18s ease, border-color 0.18s ease;
}
.copy-btn:hover { color: var(--mint); border-bottom-color: var(--mint); }

.footer-base {
  margin-top: clamp(24px, 3.6vw, 42px);
  padding-top: 18px;
  border-top: 1px solid var(--steel);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 28px;
  font-size: 0.76rem;
  color: var(--mist);
}
.footer-copy { margin: 0; }
.footer-legal { list-style: none; display: flex; flex-wrap: wrap; gap: 18px; }
.footer-legal a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s ease, border-color 0.18s ease;
}
.footer-legal a:hover { color: var(--sand); border-bottom-color: var(--sand); }
.footer-icp {
  margin: 0;
  font-family: var(--font-data);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: #5A7793;
}

/* ---------- 8. 基础组件 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6em;
  padding: 0.85em 1.6em;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.88rem;
  letter-spacing: 0.12em;
  line-height: 1.2;
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 2px;
  cursor: pointer;
  background: var(--tactic);
  color: var(--paper);
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary { background: var(--sand); border-color: var(--sand); color: #08131F; }
.btn--primary:hover { background: var(--sandpale); border-color: var(--sandpale); }

.btn--ghost { background: transparent; border-color: var(--steel); color: var(--paper); }
.btn--ghost:hover { border-color: var(--sand); color: var(--sand); }

.btn--quiet {
  padding: 0.3em 0.1em;
  background: transparent;
  border: 0;
  border-bottom: 1px solid rgba(58, 242, 196, 0.45);
  border-radius: 0;
  color: var(--mint);
}
.btn--quiet:hover { border-bottom-color: var(--mint); transform: none; }

.tag {
  display: inline-block;
  padding: 0.32em 0.72em;
  font-family: var(--font-data);
  font-size: 0.64rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  line-height: 1.3;
  color: var(--sandpale);
  background: rgba(22, 50, 79, 0.9);
  border: 1px solid var(--steel);
  border-radius: 2px;
}
.tag--coral { color: var(--coral); border-color: rgba(255, 111, 78, 0.42); background: rgba(184, 75, 54, 0.14); }
.tag--mint { color: var(--mint); border-color: rgba(58, 242, 196, 0.36); background: rgba(28, 155, 130, 0.14); }

.stat { display: flex; flex-direction: column; gap: 4px; }
.stat__num {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: clamp(1.8rem, 3.4vw, 2.9rem);
  letter-spacing: 0.02em;
  line-height: 1;
  color: var(--mint);
  font-variant-numeric: tabular-nums;
}
.stat__label {
  font-family: var(--font-data);
  font-size: 0.66rem;
  letter-spacing: 0.18em;
  color: var(--mist);
}

.card {
  position: relative;
  padding: clamp(16px, 2vw, 26px);
  background: linear-gradient(158deg, #0D2137 0%, #0A1A2A 100%);
  border: 1px solid var(--steel);
  border-radius: 2px;
  overflow: hidden;
  transition: border-color 0.24s ease, transform 0.24s ease;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 2px;
  background: var(--sand);
  transform: scaleY(0);
  transform-origin: top center;
  transition: transform 0.3s cubic-bezier(0.22, 0.9, 0.24, 1);
}
.card:hover { border-color: rgba(217, 180, 106, 0.55); transform: translateY(-3px); }
.card:hover::before { transform: scaleY(1); }

.breadcrumb { padding-block: 20px 4px; }
.breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  color: var(--mist);
}
.breadcrumb li { display: flex; align-items: center; gap: 8px; }
.breadcrumb li + li::before { content: "/"; color: var(--steel); }
.breadcrumb a { color: var(--mist); text-decoration: none; transition: color 0.18s ease; }
.breadcrumb a:hover { color: var(--sand); }
.breadcrumb [aria-current="page"] { color: var(--sandpale); }

.filter-bar { display: flex; flex-wrap: wrap; gap: 10px; }
.filter-btn {
  padding: 0.55em 1.05em;
  background: transparent;
  border: 1px solid var(--steel);
  border-radius: 999px;
  color: var(--mist);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.76rem;
  letter-spacing: 0.12em;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.filter-btn:hover { color: var(--paper); border-color: var(--sand); }
.filter-btn[aria-pressed="true"] {
  background: var(--coral);
  border-color: var(--coral);
  color: #180A06;
}
[data-filter-item].is-filtered { display: none; }

/* ---------- 9. 图片容器基础 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  isolation: isolate;
  background: var(--tactic);
  border: 1px solid var(--steel);
  border-radius: 2px;
}
.media > img,
.media > picture > img,
.media > video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.82) contrast(1.06) brightness(0.86);
}
.media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(7, 21, 35, 0.08) 0%, rgba(7, 21, 35, 0.55) 62%, rgba(3, 10, 18, 0.88) 100%);
  pointer-events: none;
}
.media--wide { aspect-ratio: 16 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media--slant { clip-path: polygon(0 0, 100% 0, 100% 90%, 0 100%); }
.media--slant-x { clip-path: polygon(5% 0, 100% 0, 95% 100%, 0 100%); }
.media__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 2;
  padding: 14px 16px;
  font-family: var(--font-data);
  font-size: 0.64rem;
  letter-spacing: 0.14em;
  color: var(--sandpale);
}

/* ---------- 10. 进入动效 ---------- */
.reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.55s ease, transform 0.55s cubic-bezier(0.22, 0.9, 0.24, 1);
  transition-delay: var(--reveal-delay, 0ms);
}
.reveal-ready [data-reveal].is-in {
  opacity: 1;
  transform: none;
}

/* 目录高亮 */
[data-scroll-spy] a.is-active {
  color: var(--sand);
  border-bottom-color: var(--sand);
}

/* ---------- 11. 轻提示 ---------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: 26px;
  z-index: 300;
  transform: translate(-50%, 14px);
  padding: 0.72em 1.3em;
  background: var(--sandpale);
  color: #08131F;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 0.82rem;
  letter-spacing: 0.1em;
  border-radius: 2px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
}
.toast.is-visible { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 12. 响应式 ---------- */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 899px) {
  body {
    padding-left: 0;
    padding-top: var(--topbar);
  }

  .site-header {
    inset: 0 0 auto 0;
    width: auto;
    height: var(--topbar);
    flex-direction: row;
    align-items: center;
    gap: 12px;
    padding: 0 clamp(14px, 4vw, 22px);
    border-right: 0;
    border-bottom: 1px solid var(--steel);
    overflow: visible;
    backdrop-filter: blur(6px);
  }

  .brand {
    flex-direction: row;
    align-items: center;
    gap: 10px;
    padding: 0;
    margin-right: auto;
  }
  .brand__rule { width: 22px; height: 2px; background: var(--sand); }
  .brand__cn {
    writing-mode: horizontal-tb;
    font-size: 1rem;
    letter-spacing: 0.2em;
    line-height: 1;
  }
  .brand__en { display: none; }

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

  .site-nav {
    position: fixed;
    top: var(--topbar);
    left: 0;
    bottom: 0;
    width: min(84vw, 340px);
    flex: initial;
    margin-top: 0;
    padding: 22px 18px 28px;
    background: linear-gradient(180deg, #0D2137 0%, #081A2B 100%);
    border-right: 1px solid var(--steel);
    box-shadow: 24px 0 60px rgba(3, 10, 18, 0.55);
    overflow-y: auto;
    overscroll-behavior: contain;
    transform: translateX(-102%);
    transition: transform 0.36s cubic-bezier(0.22, 0.9, 0.24, 1);
    z-index: 130;
  }
  .site-nav[data-open="true"] { transform: translateX(0); }

  .nav-kicker { text-align: left; padding: 0 8px; }

  .nav-list { padding: 0; gap: 0; }
  .nav-link {
    flex-direction: row;
    align-items: baseline;
    gap: 12px;
    padding: 13px 8px;
    border-bottom: 1px solid rgba(43, 64, 88, 0.55);
  }
  .nav-link__num { font-size: 0.68rem; }
  .nav-link__label { font-size: 1rem; letter-spacing: 0.1em; }
  .nav-link[aria-current="page"]::before {
    left: 0;
    top: 0;
    transform: none;
    width: 2px;
    height: 100%;
  }

  .nav-shortcuts { padding: 16px 0 0; }
  .shortcut-list { grid-template-columns: 1fr; }
  .shortcut {
    padding: 11px 12px;
    text-align: left;
    font-size: 0.82rem;
    letter-spacing: 0.1em;
  }

  .rail-status { margin-top: 22px; padding: 16px 0 0; }
  .rail-status__item { font-size: 0.64rem; }

  .scroll-progress {
    top: auto;
    bottom: -1px;
    left: 0;
    right: 0;
    width: 100%;
    height: 2px;
    transform: scaleX(var(--progress, 0));
    transform-origin: left center;
  }

  .grid--2,
  .grid--3 { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer-base { flex-direction: column; align-items: flex-start; gap: 14px; }
  .footer-legal { gap: 14px; }
  .toast { left: 16px; right: 16px; bottom: 16px; transform: translateY(14px); text-align: center; }
  .toast.is-visible { transform: translateY(0); }
}

/* ---------- 13. 减少动效 ---------- */
@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;
  }
  [data-reveal],
  .reveal-ready [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
  }
  .btn:hover,
  .card:hover,
  .footer-links a:hover { transform: none; }
}