/* =====================================================================
   银河主页 WELCOME「CN」品牌站 · 共享样式表 /assets/site.css
   深空银河底色 · 左侧星轨导航 · Bento 信息板 · 锐利直角与精密网格
   ===================================================================== */

/* ---------- 1. 设计令牌 ---------- */
:root {
  --ink: #0B1026;
  --ink-deep: #05070F;
  --nebula: #4A3A8C;
  --cyan: #35E0D0;
  --silver: #E8ECF5;
  --gold: #F2A33C;
  --slate: #6E7A9B;
  --fog: #F4F6FA;
  --mint: #3FBF8F;

  --line: rgba(232, 236, 245, 0.12);
  --line-strong: rgba(232, 236, 245, 0.26);
  --grid-line: rgba(232, 236, 245, 0.055);

  --rail: 0px;
  --header-h: 60px;
  --shell: 1240px;
  --ease-track: cubic-bezier(0.22, 0.61, 0.36, 1);
  --dur-fast: 240ms;
  --dur: 320ms;
  --dur-slow: 420ms;

  --font-sans: "PingFang SC", "HarmonyOS Sans SC", "Source Han Sans SC",
    "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-narrow: "PingFang SC", "HarmonyOS Sans SC", "Source Han Sans SC",
    "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", "Cascadia Mono", "JetBrains Mono",
    Consolas, "Liberation Mono", "Courier New", monospace;
}

/* ---------- 2. 重置与基础排版 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  padding-left: var(--rail);
  min-height: 100vh;
  background-color: var(--ink-deep);
  background-image:
    radial-gradient(1200px 640px at 78% -8%, rgba(74, 58, 140, 0.34), transparent 68%),
    radial-gradient(760px 420px at 8% 14%, rgba(53, 224, 208, 0.07), transparent 70%);
  background-repeat: no-repeat;
  color: var(--silver);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.8;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  margin: 0;
  font-family: var(--font-narrow);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: 0.05em;
  color: var(--silver);
}

h1 { font-size: clamp(1.9rem, 5vw, 3rem); }
h2 { font-size: clamp(1.45rem, 3.6vw, 2.15rem); }
h3 { font-size: clamp(1.1rem, 2.4vw, 1.35rem); }

p { margin: 0; }

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

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

a {
  color: var(--cyan);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-track);
}
a:hover { color: #86f2e7; }

button, input, select, textarea { font: inherit; color: inherit; }

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

hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: 40px 0;
}

::selection { background: rgba(53, 224, 208, 0.28); color: #ffffff; }

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

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
}

/* ---------- 3. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: -80px;
  left: 16px;
  z-index: 200;
  display: inline-block;
  padding: 11px 20px;
  background: var(--gold);
  color: #1B1206;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  border-radius: 2px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  transition: top var(--dur-fast) var(--ease-track);
}
.skip-link:focus,
.skip-link:focus-visible {
  top: 14px;
  color: #1B1206;
  outline-offset: 4px;
}

/* ---------- 4. 通用容器与章节节奏 ---------- */
.container {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: 20px;
}

@media (min-width: 768px) {
  .container { padding-inline: 32px; }
}

@media (min-width: 1440px) {
  :root { --shell: 1320px; }
}

.section {
  position: relative;
  padding: 64px 0;
}

@media (min-width: 1024px) {
  .section { padding: 96px 0; }
}

.section--deep {
  background:
    radial-gradient(900px 420px at 88% 0%, rgba(74, 58, 140, 0.24), transparent 70%),
    var(--ink-deep);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.section--ink {
  background: linear-gradient(180deg, var(--ink) 0%, #080D1E 100%);
  border-top: 1px solid var(--line);
}

.section--fog {
  background: var(--fog);
  color: #141A2E;
}

.section--fog h1,
.section--fog h2,
.section--fog h3 { color: #0B1026; }

.section--fog p { color: #2B3350; }

.section--fog a { color: #1F6E66; }

.section--fog a:hover { color: #0B1026; }

.section--fog .eyebrow { color: var(--nebula); }

.section--fog .section__lead { color: #3A4467; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 26px;
  height: 1px;
  background: currentColor;
  opacity: 0.75;
}

.section__title {
  letter-spacing: 0.05em;
}

.section__lead {
  max-width: 62ch;
  margin-top: 16px;
  font-size: 1rem;
  color: #B9C2D8;
}

/* ---------- 5. 头部 · 品牌 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: rgba(5, 7, 15, 0.94);
  border-bottom: 1px solid var(--line);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
}

.site-header::after {
  content: "";
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, transparent, rgba(53, 224, 208, 0.5), rgba(74, 58, 140, 0.6), transparent);
  pointer-events: none;
  opacity: 0.8;
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--silver);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-track);
}

.brand:hover { color: #ffffff; }

.brand__mark {
  position: relative;
  flex: none;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: radial-gradient(circle at 34% 32%,
    #E8ECF5 0 16%, var(--cyan) 22% 34%, var(--nebula) 58%, #05070F 100%);
  box-shadow:
    0 0 0 1px rgba(53, 224, 208, 0.32),
    0 0 18px rgba(53, 224, 208, 0.22);
}

.brand__mark::after {
  content: "";
  position: absolute;
  inset: -6px -10px;
  border: 1px solid rgba(53, 224, 208, 0.42);
  border-radius: 50%;
  transform: rotate(-24deg);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.15;
}

.brand__name {
  font-family: var(--font-narrow);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.14em;
  color: currentColor;
}

.brand__meta {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--slate);
}

.brand--footer .brand__mark { width: 22px; height: 22px; }
.brand--footer .brand__name { font-size: 16px; }

/* ---------- 6. 头部 · 移动端开关 ---------- */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 13px;
  background: transparent;
  border: 1px solid var(--line-strong);
  border-radius: 2px;
  color: var(--silver);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.18em;
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease-track),
    color var(--dur-fast) var(--ease-track),
    background var(--dur-fast) var(--ease-track);
}

.nav-toggle:hover {
  border-color: rgba(53, 224, 208, 0.6);
  color: var(--cyan);
  background: rgba(53, 224, 208, 0.08);
}

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 10px;
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 1.5px;
  background: currentColor;
  transition: transform var(--dur-fast) var(--ease-track);
}

.nav-toggle__bars::before { top: 0; }
.nav-toggle__bars::after { bottom: 0; }

.site-header[data-open] .nav-toggle__bars::before { transform: translateY(4px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars::after { transform: translateY(-4px) rotate(-45deg); }

.nav-toggle__label { white-space: nowrap; }

/* ---------- 7. 头部 · 轨道导航（移动抽屉） ---------- */
.site-nav {
  position: fixed;
  top: var(--header-h);
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 79;
  display: flex;
  flex-direction: column;
  padding: 22px 20px 36px;
  overflow-y: auto;
  overscroll-behavior: contain;
  background: linear-gradient(180deg, #05070F 0%, #0B1026 58%, #05070F 100%);
  border-top: 1px solid var(--line);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition:
    opacity var(--dur) var(--ease-track),
    transform var(--dur) var(--ease-track),
    visibility var(--dur) linear;
}

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

.site-nav__caption {
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--slate);
}

.site-nav__list {
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin-top: 14px;
}

.site-nav__item { min-width: 0; }

.site-nav__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 13px 14px 13px 18px;
  border-radius: 2px;
  color: var(--silver);
  transition:
    background var(--dur-fast) var(--ease-track),
    color var(--dur-fast) var(--ease-track);
}

.site-nav__link::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 2px;
  height: 0;
  background: var(--cyan);
  transform: translateY(-50%);
  transition: height var(--dur) var(--ease-track);
}

.site-nav__link:hover {
  background: rgba(74, 58, 140, 0.3);
  color: #ffffff;
}

.site-nav__link:hover::before { height: 58%; }

.site-nav__code {
  min-width: 22px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate);
  transition: color var(--dur-fast) var(--ease-track);
}

.site-nav__label {
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.site-nav__link[aria-current="page"] {
  background: rgba(53, 224, 208, 0.09);
  color: #ffffff;
}

.site-nav__link[aria-current="page"]::before { height: 100%; }

.site-nav__link[aria-current="page"] .site-nav__code { color: var(--cyan); }

.site-nav__link[aria-current="page"] .site-nav__label { font-weight: 800; }

.site-nav__foot {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: auto;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.site-nav__note {
  font-size: 12px;
  line-height: 1.7;
  color: var(--slate);
}

/* ---------- 8. 按钮体系 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 2px;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.4;
  text-decoration: none;
  cursor: pointer;
  transition:
    background var(--dur-fast) var(--ease-track),
    color var(--dur-fast) var(--ease-track),
    border-color var(--dur-fast) var(--ease-track),
    box-shadow var(--dur-fast) var(--ease-track),
    transform var(--dur-fast) var(--ease-track);
}

.btn--gold {
  background: var(--gold);
  color: #1B1206;
  box-shadow: 0 0 0 1px rgba(242, 163, 60, 0.35);
}

.btn--gold:hover {
  background: #FFB454;
  color: #1B1206;
  transform: translateY(-1px);
  box-shadow: 0 10px 26px rgba(242, 163, 60, 0.26);
}

.btn--cyan {
  color: var(--cyan);
  border-color: rgba(53, 224, 208, 0.5);
}

.btn--cyan:hover {
  background: rgba(53, 224, 208, 0.12);
  color: #8BF3E8;
  border-color: rgba(53, 224, 208, 0.8);
}

.btn--ghost {
  color: var(--silver);
  border-color: var(--line-strong);
}

.btn--ghost:hover {
  color: var(--cyan);
  border-color: rgba(53, 224, 208, 0.6);
  background: rgba(53, 224, 208, 0.06);
}

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

/* ---------- 9. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 22px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--slate);
}

.breadcrumb__separator,
.breadcrumb__sep {
  color: rgba(110, 122, 155, 0.6);
}

.breadcrumb__link {
  color: var(--slate);
}

.breadcrumb__link:hover { color: var(--cyan); }

.breadcrumb__current {
  color: var(--cyan);
  letter-spacing: 0.14em;
}

/* ---------- 10. 12 列栅格与 Bento 拼块 ---------- */
.grid-12 {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

@media (min-width: 768px) {
  .grid-12 {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 20px;
  }
  .span-3 { grid-column: span 3; }
  .span-4 { grid-column: span 4; }
  .span-5 { grid-column: span 5; }
  .span-6 { grid-column: span 6; }
  .span-7 { grid-column: span 7; }
  .span-8 { grid-column: span 8; }
  .span-12 { grid-column: span 12; }
}

.bento {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.bento__cell {
  position: relative;
  padding: 26px 24px;
  background: linear-gradient(160deg, rgba(74, 58, 140, 0.22), rgba(5, 7, 15, 0.62));
  border: 1px solid var(--line);
  border-radius: 2px;
  overflow: hidden;
}

.bento__cell::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 100% 0%, rgba(53, 224, 208, 0.14), transparent 62%);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur) var(--ease-track);
}

.bento__cell:hover::after { opacity: 1; }

.bento__code {
  display: block;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--slate);
}

@media (min-width: 900px) {
  .bento {
    grid-template-columns: repeat(12, minmax(0, 1fr));
    gap: 18px;
  }
  .bento__cell { grid-column: span 12; }
  .bento__cell--focus { grid-column: span 7; }
  .bento__cell--aux { grid-column: span 5; }
  .bento__cell--half { grid-column: span 6; }
  .bento__cell--third { grid-column: span 4; }
}

/* ---------- 11. 卡片 / 标签 / 数据条 ---------- */
.card {
  padding: 24px;
  background: rgba(5, 7, 15, 0.55);
  border: 1px solid var(--line);
  border-radius: 2px;
  transition: border-color var(--dur) var(--ease-track),
    background var(--dur) var(--ease-track);
}

.card:hover {
  border-color: rgba(53, 224, 208, 0.35);
  background: rgba(11, 16, 38, 0.72);
}

.card__meta {
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--slate);
}

.card__title {
  margin-bottom: 10px;
  font-size: 17px;
  letter-spacing: 0.05em;
  color: var(--silver);
}

.card__body {
  font-size: 15px;
  line-height: 1.75;
  color: #B9C2D8;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border: 1px solid rgba(53, 224, 208, 0.4);
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.tag--mint {
  border-color: rgba(63, 191, 143, 0.5);
  color: var(--mint);
}

.tag--gold {
  border-color: rgba(242, 163, 60, 0.5);
  color: var(--gold);
}

.stat-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

@media (min-width: 768px) {
  .stat-row { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

.stat__value {
  font-family: var(--font-mono);
  font-size: 1.7rem;
  letter-spacing: 0.02em;
  color: var(--silver);
}

.stat__label {
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--slate);
}

/* ---------- 12. 可访问分段切换 ---------- */
.tablist {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  border-bottom: 1px solid var(--line);
}

.tab {
  position: relative;
  padding: 11px 18px;
  background: transparent;
  border: 1px solid transparent;
  border-bottom: 2px solid transparent;
  border-radius: 2px 2px 0 0;
  color: var(--slate);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition:
    color var(--dur-fast) var(--ease-track),
    background var(--dur-fast) var(--ease-track),
    border-color var(--dur-fast) var(--ease-track);
}

.tab:hover {
  color: var(--silver);
  background: rgba(74, 58, 140, 0.22);
}

.tab[aria-selected="true"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.tabpanel {
  padding-top: 22px;
}

.tabpanel[hidden] { display: none; }

/* ---------- 13. 复制按钮 ---------- */
.copy-btn {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 11px;
  background: transparent;
  border: 1px solid var(--line-strong);
  border-radius: 2px;
  color: var(--slate);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  cursor: pointer;
  transition:
    color var(--dur-fast) var(--ease-track),
    border-color var(--dur-fast) var(--ease-track),
    background var(--dur-fast) var(--ease-track);
}

.copy-btn:hover {
  color: var(--cyan);
  border-color: rgba(53, 224, 208, 0.5);
  background: rgba(53, 224, 208, 0.08);
}

.copy-btn[data-copied="true"] {
  color: var(--mint);
  border-color: rgba(63, 191, 143, 0.55);
  background: rgba(63, 191, 143, 0.1);
}

/* ---------- 14. 正文长阅读 ---------- */
.prose {
  max-width: 72ch;
  font-size: 17px;
  line-height: 1.8;
  color: #B9C2D8;
}

.prose h2 {
  margin: 36px 0 14px;
  font-size: 1.35rem;
  color: var(--silver);
}

.prose h3 {
  margin: 26px 0 10px;
  font-size: 1.1rem;
  color: var(--silver);
}

.prose p + p { margin-top: 16px; }

.prose ul { margin: 16px 0; }

.prose li {
  position: relative;
  margin-top: 8px;
  padding-left: 20px;
}

.prose li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 0.78em;
  width: 6px;
  height: 1px;
  background: var(--cyan);
}

.prose a {
  color: var(--cyan);
  border-bottom: 1px solid rgba(53, 224, 208, 0.4);
}

.prose a:hover { border-bottom-color: var(--cyan); }

.section--fog .prose { color: #2B3350; }
.section--fog .prose h2,
.section--fog .prose h3 { color: #0B1026; }

/* ---------- 15. 图片容器 ---------- */
.media {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 2px;
  background:
    radial-gradient(120% 90% at 82% 8%, rgba(74, 58, 140, 0.5), transparent 62%),
    linear-gradient(150deg, #05070F 0%, #0B1026 46%, #171436 100%);
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(5, 7, 15, 0) 42%, rgba(5, 7, 15, 0.62) 100%);
  pointer-events: none;
}

.media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.85) contrast(1.06) hue-rotate(-6deg);
}

.media--wide { aspect-ratio: 21 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }

.media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate);
}

/* ---------- 16. 滚动显现 ---------- */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition:
    opacity var(--dur-slow) var(--ease-track),
    transform var(--dur-slow) var(--ease-track);
}

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

/* ---------- 17. 页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background: var(--ink);
  border-top: 1px solid var(--line);
  color: var(--silver);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 68px 68px;
  pointer-events: none;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent 86%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent 86%);
}

.site-footer > .container {
  position: relative;
  z-index: 1;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  padding: 48px 0 36px;
}

@media (min-width: 640px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1.5fr 1fr 1fr 1.15fr;
    gap: 36px;
    padding: 56px 0 44px;
  }
}

.footer-col {
  min-width: 0;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 14px;
}

.footer-col__title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.footer-col__desc {
  max-width: 36ch;
  font-size: 14px;
  line-height: 1.75;
  color: #A9B3CC;
}

.footer-coord {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate);
}

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-link {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  color: var(--silver);
  font-size: 14px;
  letter-spacing: 0.03em;
  transition: color var(--dur-fast) var(--ease-track);
}

.footer-link:hover { color: var(--cyan); }

.footer-link__code {
  min-width: 22px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--slate);
}

.footer-link:hover .footer-link__code { color: var(--cyan); }

.footer-contact {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  padding: 28px 0;
  border-top: 1px solid var(--line);
}

@media (min-width: 900px) {
  .footer-contact {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
    align-items: start;
  }
}

.footer-contact__item {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
  min-width: 0;
}

.footer-contact__label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--slate);
}

.footer-contact__value {
  font-size: 14px;
  line-height: 1.7;
  color: var(--silver);
  word-break: break-word;
  overflow-wrap: anywhere;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 18px;
  padding: 20px 0 34px;
  border-top: 1px solid var(--line);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--slate);
}

.footer-legal a {
  color: var(--slate);
  transition: color var(--dur-fast) var(--ease-track);
}

.footer-legal a:hover { color: var(--cyan); }

.footer-legal__copy { color: var(--slate); }

.footer-legal__sep {
  display: inline-block;
  width: 1px;
  height: 12px;
  background: var(--line-strong);
}

/* ---------- 18. 桌面端 · 左侧星轨导航 ---------- */
@media (min-width: 1024px) {
  :root {
    --rail: 272px;
    --header-h: 0px;
  }

  body { padding-left: var(--rail); }

  html { scroll-padding-top: 24px; }

  .site-header {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: var(--rail);
    border-bottom: 0;
    border-right: 1px solid var(--line);
    background: linear-gradient(180deg, #05070F 0%, #0B1026 46%, #05070F 100%);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }

  .site-header__inner {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    height: 100%;
    padding: 30px 22px 24px;
    gap: 26px;
  }

  .nav-toggle { display: none; }

  .site-nav {
    position: static;
    flex: 1 1 auto;
    min-height: 0;
    padding: 0;
    background: none;
    border-top: 0;
    overflow: visible;
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .site-nav__list {
    margin-top: 12px;
    overflow-y: auto;
  }

  .site-nav__foot { margin-top: auto; }
}

/* ---------- 19. 无障碍与动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  html { scroll-behavior: auto; }

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