/* ============================================================
   银河信誉官网 · 共享样式 /assets/site.css
   夜航导航台视觉体系：深空蓝黑基底 + 银河紫/青金轨道 + 暖金刻度
   ============================================================ */

/* ---------- 1. 变量 ---------- */
:root {
  --gt-void: #060A18;
  --gt-nebula: #0D1530;
  --gt-orbit: #1C2545;
  --gt-violet: #6C4CF1;
  --gt-cyan: #22D3C5;
  --gt-gold: #E8B961;
  --gt-rock: #9AA6C4;
  --gt-paper: #F2F4FA;
  --gt-moss: #5E8C6A;
  --gt-clay: #C4744F;

  --gt-ff: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  --gt-ff-mono: ui-monospace, SFMono-Regular, "JetBrains Mono", "Roboto Mono", Menlo, Consolas, monospace;

  --gt-shell: 1240px;
  --gt-gutter: 24px;
  --gt-header-h: 76px;
  --gt-radius: 3px;
  --gt-ease: cubic-bezier(.22, .61, .36, 1);
}

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

html {
  background: var(--gt-void);
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--gt-header-h) + 24px);
}

body {
  margin: 0;
  padding-top: var(--gt-header-h);
  background: transparent;
  color: var(--gt-paper);
  font-family: var(--gt-ff);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: .01em;
  overflow-x: hidden;
}

/* 星野背景：径向光晕 + 细密星点，全站统一，不铺在任何内容块之上 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  pointer-events: none;
  background:
    radial-gradient(1100px 640px at 78% -10%, rgba(108, 76, 241, .22), transparent 62%),
    radial-gradient(820px 520px at 4% 10%, rgba(34, 211, 197, .12), transparent 60%),
    radial-gradient(760px 720px at 94% 86%, rgba(108, 76, 241, .15), transparent 66%),
    linear-gradient(180deg, #070B1B 0%, #060A18 46%, #050813 100%);
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: .3;
  background-image:
    radial-gradient(rgba(242, 244, 250, .55) 0.6px, transparent 0.8px),
    radial-gradient(rgba(154, 166, 196, .4) 0.6px, transparent 0.8px);
  background-size: 220px 220px, 340px 340px;
  background-position: 0 0, 92px 134px;
}

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

/* ---------- 3. 中文排版 ---------- */
h1, h2, h3, h4, h5 {
  margin: 0 0 .62em;
  font-weight: 700;
  line-height: 1.28;
  letter-spacing: .04em;
  color: var(--gt-paper);
}
h1 { font-size: clamp(32px, 5vw, 60px); line-height: 1.14; letter-spacing: .06em; }
h2 { font-size: clamp(25px, 3.2vw, 36px); }
h3 { font-size: clamp(19px, 2vw, 24px); }
h4 { font-size: 17px; letter-spacing: .05em; }

p { margin: 0 0 1.1em; }
p:last-child { margin-bottom: 0; }

a {
  color: var(--gt-cyan);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color .18s var(--gt-ease);
}
a:hover { color: #74EDE3; }

strong { color: var(--gt-paper); font-weight: 600; }
small { font-size: 13px; line-height: 1.7; color: var(--gt-rock); }

code, kbd, samp { font-family: var(--gt-ff-mono); font-size: .86em; letter-spacing: .06em; }

.gt-mono {
  font-family: var(--gt-ff-mono);
  font-size: .88em;
  letter-spacing: .08em;
  font-variant-numeric: tabular-nums;
}

.gt-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--gt-ff-mono);
  font-size: 12px;
  letter-spacing: .2em;
  color: var(--gt-rock);
  text-transform: uppercase;
}
.gt-eyebrow::before {
  content: "";
  width: 18px;
  height: 1px;
  background: linear-gradient(90deg, var(--gt-violet), var(--gt-cyan));
}

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

/* ---------- 4. 布局容器与网格 ---------- */
.gt-wrap {
  width: min(100% - 40px, var(--gt-shell));
  margin-inline: auto;
}
.gt-wrap--narrow { width: min(100% - 40px, 840px); }

.gt-main { display: block; }

.gt-section { padding: 72px 0; }
.gt-section--tight { padding: 44px 0; }

.gt-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 28px var(--gt-gutter);
}
.gt-w-4 { grid-column: span 4; }
.gt-w-6 { grid-column: span 6; }
.gt-w-8 { grid-column: span 8; }
.gt-w-9 { grid-column: span 9; }
.gt-w-12 { grid-column: span 12; }

/* ---------- 5. 通用按钮 ---------- */
.gt-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 24px;
  font-size: 14px;
  letter-spacing: .08em;
  line-height: 1.3;
  border: 1px solid var(--gt-orbit);
  border-radius: var(--gt-radius);
  background: rgba(13, 21, 48, .62);
  color: var(--gt-paper);
  text-decoration: none;
  cursor: pointer;
  transition: transform .16s var(--gt-ease), border-color .2s var(--gt-ease),
              background .2s var(--gt-ease), box-shadow .2s var(--gt-ease), color .2s var(--gt-ease);
}
.gt-btn:hover {
  transform: translateY(-2px);
  border-color: var(--gt-cyan);
  box-shadow: 0 12px 28px rgba(34, 211, 197, .16);
  color: var(--gt-paper);
}
.gt-btn--primary {
  background: linear-gradient(120deg, var(--gt-violet) 0%, #4A2FC4 100%);
  border-color: rgba(108, 76, 241, .72);
  color: #FFFFFF;
}
.gt-btn--primary:hover {
  border-color: var(--gt-cyan);
  box-shadow: 0 16px 34px rgba(108, 76, 241, .36);
  color: #FFFFFF;
}
.gt-btn--ghost {
  background: transparent;
  border-color: rgba(154, 166, 196, .42);
  color: var(--gt-rock);
}
.gt-btn--ghost:hover { color: var(--gt-paper); border-color: var(--gt-cyan); }

/* ---------- 6. 标签 / 状态 ---------- */
.gt-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  font-family: var(--gt-ff-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  border: 1px solid var(--gt-rock);
  border-radius: 2px;
  background: rgba(28, 37, 69, .35);
  color: var(--gt-rock);
  white-space: nowrap;
}
.gt-tag--ok { color: var(--gt-moss); border-color: rgba(94, 140, 106, .78); background: rgba(94, 140, 106, .12); }
.gt-tag--warn { color: var(--gt-clay); border-color: rgba(196, 116, 79, .78); background: rgba(196, 116, 79, .12); }
.gt-tag--key { color: var(--gt-gold); border-color: rgba(232, 185, 97, .72); background: rgba(232, 185, 97, .1); }
.gt-tag--live { color: var(--gt-cyan); border-color: rgba(34, 211, 197, .6); background: rgba(34, 211, 197, .1); }

/* ---------- 7. 卡片与纸张叠层 ---------- */
.gt-card {
  position: relative;
  padding: 26px 24px;
  background: linear-gradient(180deg, rgba(13, 21, 48, .94), rgba(6, 10, 24, .88));
  border: 1px solid var(--gt-orbit);
  border-radius: var(--gt-radius);
  transition: transform .16s var(--gt-ease), border-color .2s var(--gt-ease),
              box-shadow .2s var(--gt-ease);
}
.gt-card:hover,
.gt-card:focus-within {
  transform: translateY(-2px);
  border-color: rgba(34, 211, 197, .62);
  box-shadow: 0 18px 40px rgba(3, 5, 14, .55);
}
.gt-card--rail { padding-left: 28px; }
.gt-card--rail::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  bottom: 18px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--gt-violet), var(--gt-cyan));
}

.gt-sheet {
  position: relative;
  padding: 28px;
  background: rgba(13, 21, 48, .74);
  border: 1px solid var(--gt-orbit);
  border-radius: var(--gt-radius);
  box-shadow:
    6px 6px 0 -1px rgba(13, 21, 48, .9),
    7px 7px 0 0 var(--gt-orbit),
    12px 12px 0 -1px rgba(13, 21, 48, .55),
    13px 13px 0 0 rgba(28, 37, 69, .45);
}

/* ---------- 8. 图片容器（供页面阶段放置图片） ---------- */
.gt-media {
  position: relative;
  display: block;
  overflow: hidden;
  border: 1px solid var(--gt-orbit);
  border-radius: var(--gt-radius);
  background:
    linear-gradient(135deg, rgba(108, 76, 241, .2), rgba(34, 211, 197, .08) 55%, rgba(6, 10, 24, .92)),
    var(--gt-nebula);
}
.gt-media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .45;
  background-image:
    linear-gradient(rgba(154, 166, 196, .13) 1px, transparent 1px),
    linear-gradient(90deg, rgba(154, 166, 196, .13) 1px, transparent 1px);
  background-size: 48px 48px;
}
.gt-media > img,
.gt-media > svg {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.gt-media--21x9 { aspect-ratio: 21 / 9; }
.gt-media--16x9 { aspect-ratio: 16 / 9; }
.gt-media--3x2 { aspect-ratio: 3 / 2; }
.gt-media--4x5 { aspect-ratio: 4 / 5; }
.gt-media--1x1 { aspect-ratio: 1 / 1; }
.gt-media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1;
  padding: 14px 16px 12px;
  font-family: var(--gt-ff-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--gt-rock);
  background: linear-gradient(180deg, transparent, rgba(6, 10, 24, .9));
}

/* ---------- 9. 面包屑 ---------- */
.gt-crumbs { padding: 30px 0 0; }
.gt-crumbs ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
  font-family: var(--gt-ff-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gt-rock);
}
.gt-crumbs li { display: inline-flex; align-items: center; gap: 6px; }
.gt-crumbs li + li::before { content: "/"; color: var(--gt-orbit); }
.gt-crumbs a { color: var(--gt-rock); text-decoration: none; }
.gt-crumbs a:hover { color: var(--gt-cyan); }
.gt-crumbs [aria-current="page"] { color: var(--gt-gold); }

/* ---------- 10. 章节目录 ---------- */
.gt-toc {
  position: sticky;
  top: calc(var(--gt-header-h) + 32px);
  padding-bottom: 24px;
}
.gt-toc__title {
  margin: 0 0 16px;
  font-family: var(--gt-ff-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .22em;
  color: var(--gt-rock);
}
.gt-toc__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--gt-orbit);
}
.gt-toc__link {
  display: block;
  padding: 9px 0 9px 16px;
  margin-left: -1px;
  border-left: 2px solid transparent;
  color: var(--gt-rock);
  font-size: 14px;
  line-height: 1.6;
  text-decoration: none;
  transition: color .18s var(--gt-ease), border-color .18s var(--gt-ease);
}
.gt-toc__link:hover { color: var(--gt-paper); }
.gt-toc__link[aria-current="true"] {
  color: var(--gt-cyan);
  border-left-color: var(--gt-cyan);
}
.gt-toc__index {
  margin-right: 8px;
  font-family: var(--gt-ff-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--gt-gold);
}

/* ---------- 11. 头部 ---------- */
.gt-skip {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 200;
  padding: 10px 18px;
  background: var(--gt-violet);
  color: #FFFFFF;
  font-size: 13px;
  letter-spacing: .08em;
  text-decoration: none;
  border-radius: 2px;
  transform: translateY(-180%);
  transition: transform .22s var(--gt-ease);
}
.gt-skip:focus { transform: none; color: #FFFFFF; }

.gt-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 90;
  background: linear-gradient(180deg, rgba(6, 10, 24, .92) 0%, rgba(6, 10, 24, .38) 100%);
  border-bottom: 1px solid transparent;
  transition: background .3s var(--gt-ease), border-color .3s var(--gt-ease),
              box-shadow .3s var(--gt-ease), backdrop-filter .3s var(--gt-ease);
}
.gt-header[data-scrolled] {
  background: rgba(13, 21, 48, .96);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom-color: var(--gt-orbit);
  box-shadow: 0 16px 42px rgba(3, 5, 14, .62);
}

.gt-header__inner {
  position: relative;
  width: min(100% - 40px, var(--gt-shell));
  margin-inline: auto;
  min-height: var(--gt-header-h);
  display: flex;
  align-items: center;
  gap: 24px;
}

.gt-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-right: auto;
  color: var(--gt-paper);
  text-decoration: none;
  flex: none;
}
.gt-brand:hover { color: var(--gt-paper); }

.gt-brand__mark {
  position: relative;
  flex: none;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  border: 1px solid var(--gt-orbit);
  background: radial-gradient(circle at 50% 50%, rgba(108, 76, 241, .55), transparent 64%);
}
.gt-brand__mark::before {
  content: "";
  position: absolute;
  inset: 6px;
  border-radius: 50%;
  border: 1px solid rgba(34, 211, 197, .5);
}
.gt-brand__mark::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 6px;
  height: 6px;
  margin: -3px 0 0 -3px;
  border-radius: 50%;
  background: var(--gt-gold);
  box-shadow: 0 0 10px rgba(232, 185, 97, .85);
}

.gt-brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}
.gt-brand__name {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .12em;
  color: var(--gt-paper);
}
.gt-brand__sub {
  margin-top: 2px;
  font-family: var(--gt-ff-mono);
  font-size: 10px;
  letter-spacing: .22em;
  color: var(--gt-rock);
}

/* 桌面导航 */
.gt-nav { display: block; }
.gt-nav__list {
  display: flex;
  align-items: center;
  gap: 26px;
  list-style: none;
}
.gt-nav__link {
  position: relative;
  display: inline-block;
  padding: 6px 0;
  font-size: 14px;
  letter-spacing: .06em;
  color: var(--gt-rock);
  text-decoration: none;
  transition: color .2s var(--gt-ease);
}
.gt-nav__link:hover { color: var(--gt-paper); }
.gt-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: linear-gradient(90deg, var(--gt-gold), rgba(232, 185, 97, .18));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .26s var(--gt-ease);
}
.gt-nav__link:hover::after { transform: scaleX(.55); }
.gt-nav__link[aria-current="page"] {
  color: var(--gt-paper);
  font-weight: 600;
}
.gt-nav__link[aria-current="page"]::after { transform: scaleX(1); }

.gt-header__cta {
  flex: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 16px;
  border: 1px solid rgba(34, 211, 197, .42);
  border-radius: var(--gt-radius);
  color: var(--gt-cyan);
  font-size: 13px;
  letter-spacing: .08em;
  text-decoration: none;
  background: rgba(34, 211, 197, .05);
  transition: background .2s var(--gt-ease), border-color .2s var(--gt-ease), color .2s var(--gt-ease);
}
.gt-header__cta:hover {
  background: rgba(34, 211, 197, .13);
  border-color: var(--gt-cyan);
  color: #8DF2E8;
}

.gt-burger {
  display: none;
  position: relative;
  flex: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--gt-orbit);
  border-radius: var(--gt-radius);
  background: rgba(13, 21, 48, .78);
  cursor: pointer;
  transition: border-color .2s var(--gt-ease), background .2s var(--gt-ease);
}
.gt-burger:hover { border-color: var(--gt-cyan); }
.gt-burger span {
  position: absolute;
  left: 11px;
  right: 11px;
  height: 1.5px;
  background: var(--gt-paper);
  border-radius: 2px;
  transition: transform .26s var(--gt-ease), opacity .2s var(--gt-ease);
}
.gt-burger span:nth-child(1) { top: 14px; }
.gt-burger span:nth-child(2) { top: 20px; }
.gt-burger span:nth-child(3) { top: 26px; }
.gt-burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.gt-burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.gt-burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

.gt-header__scan {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  overflow: hidden;
}
.gt-header__scan-fill {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--gt-violet), var(--gt-cyan) 62%, var(--gt-gold));
}

/* ---------- 12. 页脚 ---------- */
.gt-footer {
  position: relative;
  margin-top: 96px;
  background: linear-gradient(180deg, rgba(13, 21, 48, .58) 0%, rgba(6, 10, 24, .98) 62%);
  border-top: 1px solid var(--gt-orbit);
}
.gt-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(38%, 420px);
  height: 1px;
  background: linear-gradient(90deg, var(--gt-violet), var(--gt-cyan));
}

.gt-footer__grid {
  width: min(100% - 40px, var(--gt-shell));
  margin-inline: auto;
  padding: 64px 0 44px;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.4fr;
  gap: 40px 32px;
}
.gt-footer__col { min-width: 0; }

.gt-footer__brand {
  display: flex;
  align-items: center;
  gap: 12px;
}
.gt-footer__slogan {
  margin: 18px 0 6px;
  font-size: 21px;
  font-weight: 700;
  letter-spacing: .32em;
  color: var(--gt-paper);
}
.gt-footer__note {
  margin: 0;
  font-family: var(--gt-ff-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--gt-rock);
}

.gt-footer__title {
  margin: 0 0 16px;
  font-family: var(--gt-ff-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .18em;
  color: var(--gt-rock);
}

.gt-footer__list {
  list-style: none;
  display: grid;
  gap: 10px;
}
.gt-footer__link {
  color: var(--gt-paper);
  opacity: .82;
  font-size: 14px;
  text-decoration: none;
  transition: color .18s var(--gt-ease), opacity .18s var(--gt-ease);
}
.gt-footer__link:hover { color: var(--gt-cyan); opacity: 1; }

.gt-footer__meta {
  list-style: none;
  display: grid;
  gap: 12px;
  font-size: 13.5px;
  line-height: 1.7;
}
.gt-footer__key {
  display: block;
  margin-bottom: 3px;
  font-family: var(--gt-ff-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--gt-rock);
}
.gt-footer__val { color: rgba(242, 244, 250, .86); word-break: break-word; }

.gt-footer__base { border-top: 1px solid rgba(28, 37, 69, .85); }
.gt-footer__base-inner {
  width: min(100% - 40px, var(--gt-shell));
  margin-inline: auto;
  padding: 20px 0 28px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  font-family: var(--gt-ff-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--gt-rock);
}
.gt-footer__base-inner p { margin: 0; }

/* ---------- 13. 返回顶部 ---------- */
.gt-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 80;
  display: grid;
  place-items: center;
  width: 52px;
  height: 52px;
  padding: 0;
  border: 1px solid var(--gt-orbit);
  border-radius: 50%;
  background: rgba(13, 21, 48, .92);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .24s var(--gt-ease), transform .24s var(--gt-ease),
              visibility .24s var(--gt-ease), border-color .2s var(--gt-ease);
}
.gt-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: none;
}
.gt-top:hover { border-color: var(--gt-cyan); }
.gt-top__ring {
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  background: conic-gradient(
    var(--gt-cyan) calc(var(--gt-top-progress, 0) * 1%),
    rgba(154, 166, 196, .16) 0
  );
  -webkit-mask: radial-gradient(farthest-side, transparent calc(100% - 2px), #000 calc(100% - 2px));
  mask: radial-gradient(farthest-side, transparent calc(100% - 2px), #000 calc(100% - 2px));
}
.gt-top__arrow {
  position: relative;
  width: 10px;
  height: 10px;
  border-left: 1.5px solid var(--gt-paper);
  border-top: 1.5px solid var(--gt-paper);
  transform: translateY(3px) rotate(45deg);
}

/* ---------- 14. 进入视口显现 ---------- */
[data-reveal-state="out"] {
  opacity: 0;
  transform: translateY(12px);
}
[data-reveal-state="in"] {
  opacity: 1;
  transform: none;
  transition: opacity .5s var(--gt-ease), transform .5s var(--gt-ease);
}

/* ---------- 15. 平板 ---------- */
@media (max-width: 1079px) {
  .gt-header__inner { gap: 14px; }
  .gt-header__cta { display: none; }
  .gt-burger { display: block; }

  .gt-nav {
    position: absolute;
    top: calc(100% + 1px);
    left: 0;
    right: 0;
    max-height: calc(100vh - var(--gt-header-h) - 24px);
    overflow-y: auto;
    padding: 12px 20px 18px;
    background: rgba(10, 17, 38, .985);
    border: 1px solid var(--gt-orbit);
    border-radius: 0 0 var(--gt-radius) var(--gt-radius);
    box-shadow: 0 30px 64px rgba(3, 5, 14, .72);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-10px);
    transition: opacity .26s var(--gt-ease), transform .26s var(--gt-ease), visibility .26s;
  }
  .gt-nav[data-open] {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: none;
  }
  .gt-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .gt-nav__list li + li { border-top: 1px solid rgba(28, 37, 69, .72); }
  .gt-nav__link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 2px;
    font-size: 15px;
  }
  .gt-nav__link::before {
    content: "";
    flex: none;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    border: 1px solid var(--gt-rock);
    transition: background .2s var(--gt-ease), border-color .2s var(--gt-ease),
                box-shadow .2s var(--gt-ease);
  }
  .gt-nav__link::after { display: none; }
  .gt-nav__link[aria-current="page"] { color: var(--gt-gold); }
  .gt-nav__link[aria-current="page"]::before {
    background: var(--gt-gold);
    border-color: var(--gt-gold);
    box-shadow: 0 0 10px rgba(232, 185, 97, .8);
  }

  .gt-footer__grid { grid-template-columns: 1fr 1fr; }
}

/* ---------- 16. 手机 ---------- */
@media (max-width: 900px) {
  .gt-grid { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .gt-w-4, .gt-w-6, .gt-w-8, .gt-w-9 { grid-column: span 6; }

  .gt-toc {
    position: sticky;
    top: var(--gt-header-h);
    z-index: 40;
    margin-inline: -20px;
    padding: 10px 20px;
    background: rgba(10, 17, 38, .96);
    border-bottom: 1px solid var(--gt-orbit);
    -webkit-backdrop-filter: blur(8px);
    backdrop-filter: blur(8px);
  }
  .gt-toc__title { margin-bottom: 8px; }
  .gt-toc__list {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    border-left: 0;
    padding-bottom: 4px;
    scrollbar-width: thin;
  }
  .gt-toc__link {
    flex: none;
    padding: 7px 14px;
    margin-left: 0;
    border: 1px solid var(--gt-orbit);
    border-left: 1px solid var(--gt-orbit);
    border-radius: 999px;
    font-size: 13px;
    white-space: nowrap;
  }
  .gt-toc__link[aria-current="true"] {
    border-color: rgba(34, 211, 197, .7);
    background: rgba(34, 211, 197, .1);
  }
}

@media (max-width: 640px) {
  :root {
    --gt-gutter: 16px;
    --gt-header-h: 64px;
  }
  .gt-brand__mark { width: 26px; height: 26px; }
  .gt-brand__name { font-size: 15.5px; letter-spacing: .1em; }
  .gt-brand__sub { font-size: 9px; letter-spacing: .16em; }

  .gt-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px 16px; }
  .gt-w-4, .gt-w-6, .gt-w-8, .gt-w-9 { grid-column: span 4; }

  .gt-section { padding: 48px 0; }
  .gt-section--tight { padding: 32px 0; }
  .gt-sheet { padding: 22px 18px; box-shadow: 4px 4px 0 -1px rgba(13, 21, 48, .9), 5px 5px 0 0 var(--gt-orbit); }

  .gt-footer { margin-top: 64px; }
  .gt-footer__grid {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 44px 0 32px;
  }
  .gt-footer__base-inner { padding: 18px 0 24px; }

  .gt-top { right: 16px; bottom: 16px; width: 46px; height: 46px; }
}

/* ---------- 17. 减弱动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  body::after { opacity: .22; }
}