/* ==========================================================================
   经典指南 · 全站共享样式 /assets/site.css
   原点墨蓝为底 · 纸层米白为面 · 琥珀金编号 · 信号橙状态点
   ========================================================================== */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 96px;
  scroll-behavior: smooth;
}

body, h1, h2, h3, h4, h5, p, ul, ol, dl, dd, dt, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { width: 100%; border-collapse: collapse; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  /* 色彩 */
  --ink: #0B1B2B;
  --ink-2: #12293D;
  --paper: #F2EDE3;
  --paper-2: #E4DCCB;
  --amber: #C9A227;
  --signal: #E2703A;
  --moss: #7E8C7A;
  --moss-lift: #9DAF97;
  --clay: #A9714F;
  --clay-lift: #C08A66;
  --stone: #9AA7B1;
  --white: #FFFFFF;

  /* 描边 */
  --line-dark: rgba(201, 162, 39, 0.30);
  --line-stone: rgba(154, 167, 177, 0.22);
  --line-ink: rgba(11, 27, 43, 0.16);

  /* 尺度 */
  --max: 1280px;
  --gutter: clamp(20px, 4vw, 64px);
  --aside: 273px;
  --grid-unit: 32px;

  /* 字体 */
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", Georgia, serif;
  --sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --mono: ui-monospace, "JetBrains Mono", "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;

  /* 动效 */
  --ease: cubic-bezier(0.16, 1, 0.3, 1);

  /* 纸层阴影 */
  --shadow-paper:
    0 1px 0 rgba(11, 27, 43, 0.08),
    0 10px 20px -14px rgba(11, 27, 43, 0.45),
    0 28px 52px -34px rgba(11, 27, 43, 0.55);
}

/* ---------- 3. 基础排版 ---------- */
body {
  background-color: var(--ink);
  color: var(--paper);
  font-family: var(--sans);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.8;
  letter-spacing: 0.01em;
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

p { text-wrap: pretty; }

strong, b { font-weight: 600; }

::selection { background: var(--amber); color: var(--ink); }

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

/* ---------- 4. 通用工具 ---------- */
.wrap {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(64px, 9vw, 140px); }
.section--tight { padding-block: clamp(40px, 5vw, 68px); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.2em;
  color: var(--amber);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: currentColor;
  flex: 0 0 auto;
}

.rule {
  height: 0;
  border: 0;
  border-top: 1px solid var(--line-dark);
}

.rule--paper { border-top-color: var(--line-ink); }

.data {
  font-family: var(--mono);
  font-size: 0.82em;
  letter-spacing: 0.08em;
  color: var(--amber);
}

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

.grid-bg {
  background-image:
    linear-gradient(rgba(154, 167, 177, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(154, 167, 177, 0.07) 1px, transparent 1px);
  background-size: var(--grid-unit) var(--grid-unit);
}

.on-paper {
  background-color: var(--paper);
  color: var(--ink);
}

.on-paper .rule { border-top-color: var(--line-ink); }
.on-paper .eyebrow { color: var(--clay); }
.on-paper .data { color: var(--clay); }
.on-paper .media { border-color: var(--line-ink); background: var(--paper-2); }
.on-paper .media-caption { color: rgba(11, 27, 43, 0.55); }

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 14px 24px;
  font-family: var(--sans);
  font-size: 14.5px;
  font-weight: 500;
  line-height: 1.2;
  letter-spacing: 0.06em;
  border: 1px solid transparent;
  transition:
    background-color 0.18s var(--ease),
    color 0.18s var(--ease),
    border-color 0.18s var(--ease),
    transform 0.18s var(--ease);
}

.btn--primary {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--ink);
  font-weight: 600;
}

.btn--primary:hover {
  background: var(--amber);
  border-color: var(--amber);
  transform: translateY(-2px);
}

.btn--ghost {
  border-color: rgba(201, 162, 39, 0.5);
  color: var(--paper);
}

.btn--ghost:hover {
  border-color: var(--amber);
  color: var(--amber);
  transform: translateY(-2px);
}

.on-paper .btn--ghost {
  border-color: rgba(11, 27, 43, 0.35);
  color: var(--ink);
}

.on-paper .btn--ghost:hover {
  border-color: var(--clay);
  color: var(--clay);
}

/* ---------- 6. 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 500;
  line-height: 1.5;
  letter-spacing: 0.14em;
  border: 1px solid var(--line-stone);
  color: var(--stone);
  background: transparent;
}

.tag--amber { border-color: rgba(201, 162, 39, 0.55); color: var(--amber); }
.tag--moss { border-color: rgba(126, 140, 122, 0.62); color: var(--moss-lift); }
.tag--clay { border-color: rgba(169, 113, 79, 0.62); color: var(--clay-lift); }
.tag--signal { border-color: var(--signal); color: var(--signal); }

.on-paper .tag { border-color: rgba(11, 27, 43, 0.28); color: rgba(11, 27, 43, 0.66); }

/* ---------- 7. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px;
  padding-block: 22px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  color: var(--stone);
}

.breadcrumb li::after {
  content: "/";
  margin-inline: 8px;
  color: rgba(154, 167, 177, 0.45);
}

.breadcrumb li:last-child::after { content: none; }

.breadcrumb a {
  color: rgba(242, 237, 227, 0.7);
  border-bottom: 1px solid transparent;
  transition: color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.breadcrumb a:hover {
  color: var(--amber);
  border-bottom-color: rgba(201, 162, 39, 0.5);
}

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

.on-paper .breadcrumb a { color: rgba(11, 27, 43, 0.62); }
.on-paper .breadcrumb li::after { color: rgba(11, 27, 43, 0.3); }
.on-paper .breadcrumb [aria-current="page"] { color: var(--ink); }

/* ---------- 8. 正文 ---------- */
.prose {
  max-width: 68ch;
  font-size: 17px;
  line-height: 1.85;
  color: inherit;
}

.prose > * + * { margin-top: 1.05em; }

.prose h2 {
  font-size: clamp(22px, 2.4vw, 27px);
  margin-top: 2em;
  letter-spacing: -0.005em;
}

.prose h3 {
  font-size: clamp(18px, 1.8vw, 21px);
  margin-top: 1.7em;
}

.prose ul,
.prose ol { padding-left: 1.35em; }

.prose ul { list-style: none; }
.prose ul > li { position: relative; padding-left: 0.2em; }
.prose ul > li::before {
  content: "";
  position: absolute;
  left: -1em;
  top: 0.85em;
  width: 6px;
  height: 1px;
  background: var(--clay);
}

.prose ol { list-style: decimal; }
.prose ol::marker { font-family: var(--mono); color: var(--amber); }

.prose a {
  color: var(--amber);
  border-bottom: 1px solid rgba(201, 162, 39, 0.45);
}

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

.on-paper .prose a { color: var(--clay); border-bottom-color: rgba(169, 113, 79, 0.45); }

/* ---------- 9. 网格 ---------- */
.grid {
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
}

.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-12 { grid-column: span 12; }

/* ---------- 10. 图像容器 ---------- */
.media {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  background-color: var(--ink-2);
  border: 1px solid var(--line-stone);
}

.media img,
.media svg,
.media video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media--4x3 { aspect-ratio: 4 / 3; }
.media--3x2 { aspect-ratio: 3 / 2; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--16x9 { aspect-ratio: 16 / 9; }

.media-frame {
  position: relative;
  padding: 8px;
  background: rgba(201, 162, 39, 0.10);
  border: 1px solid rgba(201, 162, 39, 0.35);
}

.media-frame .media { border-color: rgba(201, 162, 39, 0.2); }

.media-caption {
  margin-top: 10px;
  font-family: var(--mono);
  font-size: 11px;
  line-height: 1.7;
  letter-spacing: 0.1em;
  color: var(--stone);
}

/* ---------- 11. 纸层卡片与刻印 ---------- */
.paper-card {
  position: relative;
  isolation: isolate;
  background: var(--paper);
  color: var(--ink);
  border: 1px solid var(--paper-2);
  box-shadow: var(--shadow-paper);
  padding: clamp(20px, 2.6vw, 34px);
}

.paper-card::before {
  content: "";
  position: absolute;
  inset: 7px -7px -7px 7px;
  border: 1px solid rgba(201, 162, 39, 0.45);
  z-index: -1;
  pointer-events: none;
}

.paper-card--dark {
  background: var(--ink-2);
  color: var(--paper);
  border-color: var(--line-stone);
}

.stamp {
  display: inline-grid;
  place-items: center;
  width: 68px;
  height: 68px;
  flex: 0 0 auto;
  border: 1px solid var(--amber);
  border-radius: 50%;
  color: var(--amber);
  font-family: var(--mono);
  font-size: 10px;
  line-height: 1.35;
  letter-spacing: 0.1em;
  text-align: center;
  padding: 6px;
}

/* ---------- 12. 可展开内容组 ---------- */
.disclosure { border-top: 1px solid var(--line-stone); }

.disclosure-trigger {
  display: flex;
  width: 100%;
  align-items: center;
  gap: 14px;
  padding: 18px 0;
  text-align: left;
  font-size: 16.5px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--paper);
  transition: color 0.16s var(--ease);
}

.disclosure-trigger::before {
  content: "";
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-right: 1.5px solid var(--amber);
  border-bottom: 1.5px solid var(--amber);
  transform: rotate(-45deg);
  transition: transform 0.2s var(--ease), border-color 0.16s var(--ease);
}

.disclosure-trigger:hover { color: var(--amber); }

.disclosure[data-open] > .disclosure-trigger::before {
  transform: rotate(45deg);
  border-color: var(--signal);
}

.disclosure-body {
  display: none;
  padding: 0 0 22px 22px;
  max-width: 68ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(242, 237, 227, 0.76);
}

.disclosure[data-open] > .disclosure-body { display: block; }

.on-paper .disclosure { border-top-color: var(--line-ink); }
.on-paper .disclosure-trigger { color: var(--ink); }
.on-paper .disclosure-trigger:hover { color: var(--clay); }
.on-paper .disclosure-body { color: rgba(11, 27, 43, 0.76); }

/* ==========================================================================
   13. 页头 · 紧凑命令栏
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background-color: var(--ink);
  background-image:
    linear-gradient(rgba(154, 167, 177, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(154, 167, 177, 0.055) 1px, transparent 1px);
  background-size: var(--grid-unit) var(--grid-unit);
  border-bottom: 1px solid var(--line-dark);
}

.scroll-meter {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--signal);
  z-index: 120;
  pointer-events: none;
  transition: width 0.1s linear;
}

.skip-link {
  position: fixed;
  top: 10px;
  left: 12px;
  z-index: 200;
  padding: 12px 18px;
  background: var(--signal);
  color: var(--ink);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  border: 1px solid var(--ink);
  transform: translateY(-180%);
  transition: transform 0.18s var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  transform: translateY(0);
  outline: 2px solid var(--paper);
  outline-offset: 2px;
}

.header-inner {
  display: flex;
  align-items: center;
  flex-wrap: nowrap;
  gap: clamp(14px, 2.2vw, 36px);
  width: 100%;
  max-width: var(--max);
  min-height: 64px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: 0 0 auto;
  padding-block: 14px;
}

.brand::after {
  content: "";
  width: 1px;
  height: 22px;
  background: var(--line-dark);
  flex: 0 0 auto;
}

.brand-mark {
  font-family: var(--serif);
  font-size: clamp(17px, 1.6vw, 20px);
  font-weight: 700;
  letter-spacing: 0.14em;
  line-height: 1;
  color: var(--paper);
}

.brand-tag {
  font-family: var(--mono);
  font-size: 10px;
  line-height: 1;
  letter-spacing: 0.2em;
  color: var(--stone);
  white-space: nowrap;
}

.command-bar {
  margin-left: auto;
  min-width: 0;
}

.command-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.command-link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 9px 11px;
  border: 1px solid transparent;
  color: rgba(242, 237, 227, 0.72);
  transition:
    background-color 0.16s var(--ease),
    color 0.16s var(--ease),
    border-color 0.16s var(--ease);
}

.command-index {
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--stone);
  transition: color 0.16s var(--ease);
}

.command-label {
  font-size: 13.5px;
  line-height: 1.4;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

.command-link:hover {
  background: var(--ink-2);
  border-color: rgba(201, 162, 39, 0.32);
  color: var(--white);
}

.command-link:hover .command-index { color: var(--amber); }

.command-link:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

.command-link[aria-current="page"] {
  background: rgba(226, 112, 58, 0.10);
  color: var(--white);
  font-weight: 600;
}

.command-link[aria-current="page"] .command-index { color: var(--amber); }

.command-link[aria-current="page"]::after {
  content: "";
  width: 5px;
  height: 5px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 3px rgba(226, 112, 58, 0.18);
}

.header-act {
  flex: 0 0 auto;
  padding: 9px 15px;
  border: 1px solid rgba(201, 162, 39, 0.55);
  color: var(--amber);
  font-size: 12.5px;
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: 0.1em;
  white-space: nowrap;
  transition:
    background-color 0.16s var(--ease),
    color 0.16s var(--ease),
    border-color 0.16s var(--ease);
}

.header-act:hover {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--ink);
  font-weight: 600;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  padding: 9px 13px;
  border: 1px solid rgba(201, 162, 39, 0.5);
  color: var(--paper);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  transition: background-color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.nav-toggle-bars {
  position: relative;
  display: block;
  width: 16px;
  height: 9px;
  flex: 0 0 auto;
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 1.5px;
  background: currentColor;
  transition: transform 0.2s var(--ease), top 0.2s var(--ease);
}

.nav-toggle-bars::before { top: 0; }
.nav-toggle-bars::after { top: 7.5px; }

.nav-toggle[aria-expanded="true"] {
  background: rgba(226, 112, 58, 0.14);
  border-color: var(--signal);
  color: var(--white);
}

.site-header[data-open] .nav-toggle-bars::before {
  top: 3.75px;
  transform: rotate(45deg);
}

.site-header[data-open] .nav-toggle-bars::after {
  top: 3.75px;
  transform: rotate(-45deg);
}

/* ==========================================================================
   14. 页脚 · 档案盒层次
   ========================================================================== */
.site-footer {
  position: relative;
  background-color: var(--ink);
  background-image:
    linear-gradient(rgba(154, 167, 177, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(154, 167, 177, 0.05) 1px, transparent 1px);
  background-size: var(--grid-unit) var(--grid-unit);
  border-top: 1px solid var(--amber);
  color: rgba(242, 237, 227, 0.78);
}

.footer-inner {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding: clamp(48px, 6vw, 84px) var(--gutter) 26px;
}

.footer-top {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px 20px;
  padding-bottom: 26px;
  border-bottom: 1px solid var(--line-stone);
}

.footer-brand {
  display: inline-flex;
  align-items: baseline;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-mark {
  font-family: var(--serif);
  font-size: clamp(20px, 2.2vw, 24px);
  font-weight: 700;
  letter-spacing: 0.16em;
  line-height: 1.2;
  color: var(--paper);
}

.footer-tag {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--stone);
}

.footer-code {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  color: var(--amber);
  white-space: nowrap;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.35fr 0.85fr 1.15fr;
  gap: clamp(28px, 4vw, 64px);
  padding-block: 40px 34px;
}

.footer-col { min-width: 0; }

.footer-title {
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.14em;
  line-height: 1.4;
  color: var(--amber);
  margin-bottom: 16px;
}

.footer-title::before {
  content: "";
  display: block;
  width: 22px;
  height: 1px;
  margin-bottom: 11px;
  background: var(--amber);
}

.footer-text {
  max-width: 34ch;
  font-size: 14px;
  line-height: 1.9;
  color: rgba(242, 237, 227, 0.72);
}

.footer-links {
  display: grid;
  gap: 1px;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 5px 0;
  font-size: 14.5px;
  line-height: 1.6;
  color: rgba(242, 237, 227, 0.8);
  transition: color 0.16s var(--ease);
}

.footer-links a::before {
  content: "";
  width: 14px;
  height: 1px;
  flex: 0 0 auto;
  background: var(--clay);
  transition: width 0.16s var(--ease), background-color 0.16s var(--ease);
}

.footer-links a:hover { color: var(--white); }
.footer-links a:hover::before { width: 22px; background: var(--signal); }

.footer-facts {
  display: grid;
  gap: 10px;
}

.footer-facts > div {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
}

.footer-facts dt {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: var(--stone);
}

.footer-facts dd {
  font-size: 13.5px;
  line-height: 1.7;
  color: rgba(242, 237, 227, 0.92);
  overflow-wrap: anywhere;
}

.footer-legal {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px 28px;
  padding-top: 22px;
  border-top: 1px solid var(--line-stone);
}

.footer-copy {
  font-family: var(--mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  line-height: 1.7;
  color: var(--stone);
}

.footer-legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 22px;
}

.footer-legal-links a {
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: rgba(242, 237, 227, 0.72);
  border-bottom: 1px solid rgba(201, 162, 39, 0.35);
  padding-bottom: 2px;
  transition: color 0.16s var(--ease), border-color 0.16s var(--ease);
}

.footer-legal-links a:hover {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

/* ---------- 回到原点 ---------- */
.origin-btn {
  position: fixed;
  right: clamp(14px, 2.4vw, 28px);
  bottom: clamp(14px, 2.4vw, 28px);
  z-index: 70;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 11px 15px;
  background: var(--ink-2);
  border: 1px solid var(--line-dark);
  color: var(--paper);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition:
    opacity 0.24s var(--ease),
    transform 0.24s var(--ease),
    visibility 0.24s linear,
    border-color 0.16s var(--ease),
    color 0.16s var(--ease);
}

.origin-btn::before {
  content: "↑";
  color: var(--signal);
  font-size: 13px;
  line-height: 1;
}

.origin-btn.is-on {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.origin-btn:hover {
  border-color: var(--signal);
  color: var(--white);
}

/* ---------- 15. 动效 ---------- */
[data-reveal] {
  transition:
    opacity 0.32s var(--ease),
    transform 0.32s var(--ease);
  transition-delay: calc(var(--reveal-delay, 0) * 60ms);
}

[data-reveal].is-concealed {
  opacity: 0;
  transform: translateY(12px);
}

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1180px) {
  .command-link { padding: 9px 8px; gap: 5px; }
  .command-label { font-size: 13px; }
  .brand-tag { display: none; }
  .brand::after { display: none; }
}

@media (max-width: 1000px) {
  html { scroll-padding-top: 78px; }

  .header-inner {
    flex-wrap: wrap;
    gap: 0;
    min-height: 0;
    padding-block: 0;
  }

  .brand {
    padding-block: 14px;
    margin-right: auto;
  }

  .brand-tag { display: none; }
  .brand::after { display: none; }
  .header-act { display: none; }
  .nav-toggle { display: inline-flex; }

  .command-bar {
    display: none;
    flex: 1 0 100%;
    margin-left: 0;
    margin-bottom: 14px;
    padding-top: 6px;
    border-top: 1px solid var(--line-dark);
  }

  .site-header[data-open] .command-bar { display: block; }

  .command-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .command-link {
    display: flex;
    padding: 13px 6px;
    gap: 12px;
    border-bottom: 1px solid var(--line-stone);
  }

  .command-index { width: 26px; }

  .command-link[aria-current="page"] {
    background: rgba(226, 112, 58, 0.08);
    padding-left: 12px;
  }

  .grid-12 { grid-template-columns: minmax(0, 1fr); }

  .col-4, .col-5, .col-6, .col-7, .col-8, .col-12 {
    grid-column: 1 / -1;
  }
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 34px;
  }

  .footer-text { max-width: 46ch; }
}

@media (max-width: 640px) {
  body { font-size: 16px; }

  .footer-top {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .footer-code { margin-left: 0; }

  .footer-facts > div {
    grid-template-columns: 54px minmax(0, 1fr);
  }

  .footer-legal {
    flex-direction: column;
    align-items: flex-start;
  }

  .prose { font-size: 16px; }
}

/* ---------- 17. 降低动效 ---------- */
@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;
  }

  [data-reveal],
  [data-reveal].is-concealed {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .origin-btn {
    transform: none;
    transition: opacity 0.01ms linear, visibility 0.01ms linear;
  }
}