/* ==========================================================================
   大红鹰官网 · 共享样式 /assets/site.css
   框架式页头 · 封底式页脚 · 硬阴影粗边框 · 等宽索引
   ========================================================================== */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

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

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

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

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

a { color: inherit; }

/* ---------- 2. 设计变量 ---------- */
:root {
  --paper: #F4EFE5;
  --paper-deep: #EAE2D3;
  --surface: #FBF7EF;
  --ink: #191410;
  --bark: #2B1F17;
  --gold: #A8782A;
  --amber: #D99A3D;
  --cinnabar: #C84630;
  --cinnabar-deep: #9C2F20;
  --gold-pale: #E7D2A8;
  --mist: #6C6257;

  --line: rgba(25, 20, 16, 0.14);
  --line-strong: rgba(25, 20, 16, 0.38);
  --line-light: rgba(231, 210, 168, 0.30);

  --font-display: "Noto Serif SC", "Songti SC", "Source Han Serif SC", "Songti TC", serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "IBM Plex Mono", "SFMono-Regular", ui-monospace, "Courier New", monospace;

  --shadow-hard: 6px 6px 0 var(--bark);
  --shadow-soft: 0 16px 34px -26px rgba(43, 31, 23, 0.78);

  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
  --wrap: 1400px;
  --header-h: 82px;
}

/* ---------- 3. 基础排版 ---------- */
body {
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.01em;
  color: var(--bark);
  text-wrap: balance;
}

h1 { font-size: clamp(2.6rem, 7vw, 6rem); }
h2 { font-size: clamp(1.6rem, 3.4vw, 2.6rem); }
h3 { font-size: clamp(1.1rem, 1.8vw, 1.35rem); }
h4 { font-size: 1.02rem; }

p { text-wrap: pretty; }

::selection { background: var(--gold-pale); color: var(--bark); }

/* ---------- 4. 可访问焦点 ---------- */
:where(a, button, [tabindex]):focus-visible {
  outline: 3px solid var(--cinnabar);
  outline-offset: 3px;
  border-radius: 2px;
}

.site-footer :where(a, button):focus-visible {
  outline-color: var(--amber);
}

/* ---------- 5. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: 0.6rem;
  left: 0.6rem;
  z-index: 300;
  transform: translateY(-180%);
  padding: 0.7rem 1.1rem;
  background: var(--bark);
  color: var(--gold-pale);
  border: 2px solid var(--gold);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  text-decoration: none;
  transition: transform 0.2s var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible { transform: translateY(0); }

/* ---------- 6. 布局容器 ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: clamp(1.1rem, 3vw, 2.75rem);
}

.section { padding-block: clamp(2.25rem, 5vw, 4.5rem); }
.section--tight { padding-block: clamp(1.4rem, 3vw, 2.5rem); }

#main-content { scroll-margin-top: calc(var(--header-h) + 1.5rem); }

[id] { scroll-margin-top: calc(var(--header-h) + 1.25rem); }

/* ---------- 7. 页头：装订脊 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background-color: var(--paper);
  border-bottom: 3px solid var(--bark);
  box-shadow: 0 12px 26px -24px rgba(43, 31, 23, 0.95);
}

.site-header::before {
  content: "";
  display: block;
  height: 6px;
  background-image: linear-gradient(
    90deg,
    var(--bark) 0 58%,
    var(--gold) 58% 84%,
    var(--cinnabar) 84% 100%
  );
}

.site-header__inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: clamp(0.6rem, 1.6vw, 1.5rem);
  width: 100%;
  max-width: var(--wrap);
  min-height: calc(var(--header-h) - 9px);
  margin-inline: auto;
  padding-inline: clamp(1.1rem, 3vw, 2.75rem);
}

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -3px;
  height: 3px;
  background-image: linear-gradient(90deg, var(--gold), var(--amber) 55%, var(--cinnabar));
  transform: scaleX(0);
  transform-origin: 0 50%;
  pointer-events: none;
  z-index: 3;
}

/* 品牌印章 */
.brand {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  flex: 0 0 auto;
  padding-block: 0.7rem;
  text-decoration: none;
  color: var(--bark);
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 2.7rem;
  height: 2.7rem;
  background-color: var(--bark);
  color: var(--gold-pale);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.12rem;
  line-height: 1;
  border: 2px solid var(--bark);
  box-shadow: 4px 4px 0 var(--gold);
  transform: rotate(-4deg);
  transition: transform 0.22s var(--ease), box-shadow 0.22s var(--ease);
}

.brand:hover .brand__mark {
  transform: rotate(0deg) translate(-1px, -1px);
  box-shadow: 6px 6px 0 var(--cinnabar);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  line-height: 1.1;
}

.brand__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.02rem, 1.35vw, 1.28rem);
  letter-spacing: 0.02em;
  color: var(--bark);
}

.brand__line {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
}

/* 移动端菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.55rem;
  margin-inline-start: auto;
  padding: 0.6rem 0.85rem;
  background-color: var(--surface);
  color: var(--bark);
  border: 2px solid var(--bark);
  box-shadow: 3px 3px 0 var(--gold-pale);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.nav-toggle:active { box-shadow: 1px 1px 0 var(--gold-pale); }

.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 18px;
}

.nav-toggle__bar {
  display: block;
  height: 2px;
  background-color: var(--bark);
  transition: transform 0.22s var(--ease), opacity 0.22s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) { opacity: 0; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  margin-inline-start: auto;
}

.nav-list {
  display: flex;
  align-items: stretch;
  border-left: 1px solid var(--line);
}

.nav-list__item { display: flex; }

.nav-link {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.18rem;
  padding: 0.62rem clamp(0.45rem, 1vw, 0.95rem);
  border-right: 1px solid var(--line);
  text-decoration: none;
  color: var(--ink);
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease);
}

.nav-link__index {
  font-family: var(--font-mono);
  font-size: 0.56rem;
  letter-spacing: 0.16em;
  color: var(--gold);
  transition: color 0.2s var(--ease);
}

.nav-link__label {
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
}

.nav-link:hover {
  background-color: var(--paper-deep);
  color: var(--bark);
}

.nav-link[aria-current="page"] {
  background-color: var(--bark);
  color: var(--surface);
}

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

.nav-link[aria-current="page"]::after {
  content: "";
  position: absolute;
  inset-inline: 0;
  bottom: 0;
  height: 4px;
  background-color: var(--cinnabar);
}

/* 页头藏书签 CTA */
.header-bookmark {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-inline-start: 0.55rem;
  padding: 0.6rem 0.95rem;
  background-color: var(--cinnabar-deep);
  color: #FFFFFF;
  border: 2px solid var(--cinnabar-deep);
  box-shadow: 4px 4px 0 var(--bark);
  font-size: 0.85rem;
  font-weight: 600;
  white-space: nowrap;
  text-decoration: none;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease),
              background-color 0.18s var(--ease), color 0.18s var(--ease);
}

.header-bookmark:hover {
  background-color: var(--bark);
  border-color: var(--bark);
  color: var(--gold-pale);
  transform: translate(-1px, -1px);
  box-shadow: 5px 5px 0 var(--gold);
}

.header-bookmark:active {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--bark);
}

.header-bookmark__pin,
.nav-bookmark__pin {
  display: block;
  flex: none;
  width: 0.5rem;
  height: 0.5rem;
  background-color: var(--gold-pale);
  transform: rotate(45deg);
}

/* 抽屉中的书签（仅移动端可见） */
.nav-bookmark { display: none; }

/* ---------- 8. 页脚：封底 ---------- */
.site-footer {
  position: relative;
  background-color: var(--bark);
  color: var(--surface);
  border-top: 6px solid var(--gold);
}

.site-footer__inner {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding: clamp(2.5rem, 5vw, 4.2rem) clamp(1.1rem, 3vw, 2.75rem) 1.6rem;
}

.site-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.75fr);
  gap: clamp(2rem, 4vw, 3.5rem);
  align-items: start;
}

.footer-brand__kicker {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--amber);
}

.footer-brand__name {
  margin-top: 0.55rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.9rem, 3.6vw, 2.8rem);
  line-height: 1.05;
  color: var(--surface);
}

.footer-brand__note {
  margin-top: 0.9rem;
  max-width: 24ch;
  font-size: 0.95rem;
  line-height: 1.8;
  color: rgba(251, 247, 239, 0.78);
}

.footer-brand__marks {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin-top: 1.15rem;
}

.footer-brand__marks li {
  padding: 0.24rem 0.5rem;
  border: 1px solid var(--line-light);
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  color: var(--gold-pale);
}

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

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.25rem, 3vw, 2.5rem);
}

.footer-col__title {
  padding-bottom: 0.6rem;
  margin-bottom: 0.85rem;
  border-bottom: 1px solid var(--line-light);
  font-family: var(--font-mono);
  font-size: 0.66rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--amber);
}

.footer-col__list { display: grid; gap: 0.55rem; }

.footer-col__link {
  display: inline-block;
  font-size: 0.94rem;
  color: var(--gold-pale);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.footer-col__link:hover {
  color: #FFFFFF;
  border-bottom-color: var(--amber);
}

/* 联系与反馈带 */
.footer-contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 1.25rem 2rem;
  align-items: start;
  margin-top: clamp(2rem, 4vw, 3rem);
  padding-top: clamp(1.4rem, 3vw, 2rem);
  border-top: 1px solid var(--line-light);
}

.footer-contact__title {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--amber);
}

.footer-contact__list { display: grid; gap: 0.5rem; }

.footer-contact__item {
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem 0.7rem;
  font-size: 0.9rem;
}

.footer-contact__key {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(251, 247, 239, 0.55);
  min-width: 4.4rem;
  padding-top: 0.28rem;
}

.footer-contact__value {
  color: var(--surface);
  word-break: break-word;
}

.footer-contact__note {
  font-size: 0.82rem;
  line-height: 1.75;
  color: rgba(251, 247, 239, 0.62);
}

.footer-contact__cta {
  justify-self: start;
  align-self: start;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.68rem 1.1rem;
  background-color: var(--cinnabar);
  color: #FFFFFF;
  border: 2px solid var(--cinnabar);
  box-shadow: 4px 4px 0 rgba(25, 20, 16, 0.45);
  font-size: 0.86rem;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease),
              background-color 0.18s var(--ease);
}

.footer-contact__cta:hover {
  background-color: #FFFFFF;
  color: var(--cinnabar-deep);
  border-color: #FFFFFF;
  transform: translate(-1px, -1px);
  box-shadow: 5px 5px 0 rgba(25, 20, 16, 0.6);
}

/* 底栏 */
.site-footer__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.7rem 1.5rem;
  margin-top: clamp(1.8rem, 3.5vw, 2.6rem);
  padding-top: 1.2rem;
  border-top: 1px solid var(--line-light);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.07em;
  color: rgba(251, 247, 239, 0.6);
}

.footer-legal-icp { color: rgba(251, 247, 239, 0.6); }
.footer-copy { color: rgba(251, 247, 239, 0.6); }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-inline-start: auto;
}

.footer-legal__link {
  color: var(--gold-pale);
  text-decoration: none;
}

.footer-legal__link:hover {
  color: #FFFFFF;
  text-decoration: underline;
  text-underline-offset: 0.28em;
}

/* 返回顶部 */
.back-top {
  position: fixed;
  right: clamp(0.9rem, 2.4vw, 1.9rem);
  bottom: clamp(0.9rem, 2.4vw, 1.9rem);
  z-index: 110;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.62rem 0.95rem;
  background-color: var(--bark);
  color: var(--gold-pale);
  border: 2px solid var(--gold);
  box-shadow: 4px 4px 0 rgba(25, 20, 16, 0.4);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  transition: transform 0.18s var(--ease), background-color 0.18s var(--ease),
              color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.back-top[hidden] { display: none; }

.back-top:hover {
  background-color: var(--cinnabar-deep);
  border-color: var(--cinnabar-deep);
  color: #FFFFFF;
  transform: translateY(-2px);
}

/* ---------- 9. 通用文本组件 ---------- */
.kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--cinnabar-deep);
}

.kicker::before {
  content: "";
  width: 1.8rem;
  height: 2px;
  background-color: currentColor;
}

.lead {
  max-width: 62ch;
  font-size: clamp(1.02rem, 1.1vw, 1.18rem);
  line-height: 1.85;
  color: var(--bark);
}

.prose { max-width: 68ch; }
.prose p { line-height: 1.92; }
.prose p + p { margin-top: 1em; }
.prose a {
  color: var(--cinnabar-deep);
  text-decoration: underline;
  text-underline-offset: 0.22em;
  text-decoration-thickness: 1px;
}

.rule {
  height: 1px;
  border: 0;
  background-color: var(--line);
}

.index-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.22rem 0.5rem;
  background-color: var(--gold-pale);
  border: 1px solid var(--gold);
  font-family: var(--font-mono);
  font-size: 0.64rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--bark);
}

.panel {
  padding: clamp(1.25rem, 3vw, 2rem);
  background-color: var(--surface);
  border: 2px solid var(--bark);
  box-shadow: var(--shadow-soft);
}

.panel__title {
  margin-bottom: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cinnabar-deep);
}

/* ---------- 10. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  padding: 0.8rem 1.4rem;
  background-color: var(--surface);
  color: var(--bark);
  border: 2px solid var(--bark);
  box-shadow: 4px 4px 0 var(--gold-pale);
  font-family: var(--font-body);
  font-size: 0.92rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease),
              background-color 0.18s var(--ease), color 0.18s var(--ease),
              border-color 0.18s var(--ease);
}

.btn:hover {
  background-color: var(--bark);
  color: var(--surface);
  box-shadow: 6px 6px 0 var(--gold);
  transform: translate(-1px, -1px);
}

.btn:active {
  transform: translate(2px, 2px);
  box-shadow: 2px 2px 0 var(--gold-pale);
}

.btn--primary {
  background-color: var(--cinnabar-deep);
  border-color: var(--cinnabar-deep);
  color: #FFFFFF;
  box-shadow: 4px 4px 0 var(--bark);
}

.btn--primary:hover {
  background-color: var(--bark);
  border-color: var(--bark);
  color: var(--gold-pale);
  box-shadow: 6px 6px 0 var(--cinnabar-deep);
}

.btn--ghost {
  background-color: transparent;
  border-color: var(--line-strong);
  box-shadow: none;
}

.btn--ghost:hover {
  background-color: var(--paper-deep);
  border-color: var(--bark);
  color: var(--bark);
  box-shadow: none;
  transform: none;
}

/* ---------- 11. 面包屑 ---------- */
.breadcrumbs {
  padding-block: 1.1rem 0;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--mist);
}

.breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumbs__item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.breadcrumbs__item:not(:last-child)::after {
  content: "/";
  color: var(--gold);
}

.breadcrumbs__link {
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.breadcrumbs__link:hover {
  color: var(--cinnabar-deep);
  border-bottom-color: var(--cinnabar);
}

.breadcrumbs__current {
  color: var(--bark);
  font-weight: 600;
}

/* ---------- 12. 网格 ---------- */
.grid {
  display: grid;
  gap: clamp(1.25rem, 3vw, 2.5rem);
}

.grid--split { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.grid--main-aside { grid-template-columns: minmax(0, 8fr) minmax(0, 4fr); }
.grid--thirds { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--halves { grid-template-columns: repeat(2, minmax(0, 1fr)); }

/* ---------- 13. 响应式图片容器 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background-color: var(--paper-deep);
  border: 2px solid var(--bark);
  box-shadow: var(--shadow-hard);
}

.media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 4 / 3;
}

.media--wide .media__img { aspect-ratio: 16 / 9; }
.media--tall .media__img { aspect-ratio: 3 / 4; }
.media--square .media__img { aspect-ratio: 1 / 1; }

.media__placeholder {
  display: grid;
  place-items: center;
  aspect-ratio: 4 / 3;
  padding: 1rem;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--bark);
  background-image:
    repeating-linear-gradient(135deg, rgba(168, 120, 42, 0.22) 0 10px, transparent 10px 20px),
    linear-gradient(160deg, var(--paper-deep), var(--gold-pale));
}

.media--wide .media__placeholder { aspect-ratio: 16 / 9; }
.media--tall .media__placeholder { aspect-ratio: 3 / 4; }
.media--square .media__placeholder { aspect-ratio: 1 / 1; }

.media__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  max-width: 100%;
  margin: 0;
  padding: 0.45rem 0.7rem;
  background-color: rgba(43, 31, 23, 0.88);
  color: var(--gold-pale);
  font-family: var(--font-mono);
  font-size: 0.62rem;
  letter-spacing: 0.12em;
}

/* ---------- 14. 滚动浮现 ---------- */
[data-reveal] {
  transition: opacity 0.32s var(--ease), transform 0.32s var(--ease);
}

[data-reveal].is-reveal-init {
  opacity: 0;
  transform: translateY(16px);
}

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

/* ---------- 15. 平板 ---------- */
@media (max-width: 1080px) {
  .site-footer__top { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 1040px) {
  .nav-toggle { display: inline-flex; }

  .header-bookmark { display: none; }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    margin-inline-start: 0;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    padding: 0.4rem clamp(1.1rem, 3vw, 2.75rem) 1.4rem;
    background-color: var(--surface);
    border-bottom: 3px solid var(--bark);
    box-shadow: 0 26px 42px -30px rgba(43, 31, 23, 0.95);
  }

  .site-nav[data-open="true"] { display: block; }
  .site-nav[data-open="false"] { display: none; }

  .nav-list {
    flex-direction: column;
    border-left: 0;
  }

  .nav-list__item { border-bottom: 1px dashed var(--line); }

  .nav-link {
    flex-direction: row;
    align-items: baseline;
    justify-content: flex-start;
    gap: 0.9rem;
    padding: 0.95rem 0.2rem;
    border-right: 0;
  }

  .nav-link__label { font-size: 1.04rem; }
  .nav-link__index { font-size: 0.62rem; }

  .nav-link[aria-current="page"] {
    background-color: transparent;
    color: var(--cinnabar-deep);
  }

  .nav-link[aria-current="page"] .nav-link__index { color: var(--gold); }

  .nav-link[aria-current="page"]::after {
    inset: auto auto 0.35rem 2.2rem;
    width: 2rem;
    height: 3px;
  }

  .nav-bookmark {
    display: flex;
    align-items: center;
    gap: 0.55rem;
    margin-top: 1.1rem;
    padding: 0.85rem 1rem;
    background-color: var(--cinnabar-deep);
    border: 2px solid var(--cinnabar-deep);
    box-shadow: 4px 4px 0 var(--gold-pale);
    color: #FFFFFF;
    font-weight: 600;
    text-decoration: none;
  }
}

/* ---------- 16. 手机 ---------- */
@media (max-width: 900px) {
  .grid--split,
  .grid--main-aside,
  .grid--thirds,
  .grid--halves { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 760px) {
  body { font-size: 16px; }

  :root { --header-h: 72px; }

  .brand__mark { width: 2.4rem; height: 2.4rem; font-size: 1rem; }
  .brand__line { display: none; }

  .footer-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .footer-legal { margin-inline-start: 0; }

  .site-footer__base { flex-direction: column; align-items: flex-start; }

  .back-top { padding: 0.55rem 0.8rem; font-size: 0.62rem; }
}

@media (max-width: 460px) {
  .footer-cols { grid-template-columns: minmax(0, 1fr); }
  .nav-toggle__label { display: none; }
}

/* ---------- 17. 减少动态效果 ---------- */
@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;
    scroll-behavior: auto !important;
  }

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