/* ============================================================
   皇家8828 · 共享样式表 /assets/site.css
   分层：reset → 变量 → 排版 → 外壳 → 组件 → 响应式 → 动效降级
   ============================================================ */

/* ---------- 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, ul, ol, li, figure, blockquote, dl, dd, fieldset {
  margin: 0;
}

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

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

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

button { background: none; border: 0; cursor: pointer; }

a { color: inherit; text-decoration: none; }

table { border-collapse: collapse; width: 100%; }

/* ---------- 2. 变量 ---------- */
:root {
  /* 品牌色 */
  --royal: #1E3A8A;
  --navy: #14245C;
  --gold: #C9A227;
  --gold-hi: #F0D87A;
  --magenta: #D6246E;
  --teal: #0E9F8E;
  --brick: #B23A2F;
  --ink: #23262B;
  --gray: #6B7280;
  --ivory: #F7F5EF;
  --white: #FFFFFF;

  /* 结构语汇 */
  --line: 2px solid var(--navy);
  --shadow: 4px 4px 0 var(--navy);
  --shadow-lg: 6px 6px 0 var(--navy);
  --shadow-gold: 4px 4px 0 var(--gold);
  --t-fast: .14s;
  --t-base: .22s;
  --ease: linear;

  /* 字体 */
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", serif;
  --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", Menlo, Consolas, monospace;

  /* 尺寸 */
  --pad: clamp(1rem, 4vw, 2.5rem);
  --gutter: clamp(1rem, 2.6vw, 1.75rem);
  --stack-gap: 1rem;
}

/* ---------- 3. 基础排版 ---------- */
body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background: var(--ivory);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.85;
  overflow-x: hidden;
}

main { flex: 1 1 auto; }

h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--navy);
}

h1 {
  font-size: clamp(2.2rem, 5vw, 4rem);
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.12;
}

h2 { font-size: clamp(1.55rem, 3.4vw, 2.4rem); }
h3 { font-size: clamp(1.18rem, 2.2vw, 1.55rem); }
h4 { font-size: 1.05rem; font-weight: 700; }

p { text-wrap: pretty; }

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

:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 2px;
  box-shadow: 0 0 0 5px rgba(30, 58, 138, .3);
}

/* ---------- 4. 骨架元素 ---------- */
.skip-link {
  position: absolute;
  top: -6rem;
  left: .75rem;
  z-index: 200;
  padding: .75rem 1.15rem;
  background: var(--royal);
  color: var(--ivory);
  border: 2px solid var(--gold);
  font-family: var(--font-mono);
  font-size: .78rem;
  font-weight: 700;
  letter-spacing: .08em;
  transition: top var(--t-base) var(--ease);
}

.skip-link:focus { top: .75rem; }

.container {
  width: min(1240px, 100%);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.section { padding-block: clamp(2.5rem, 6vw, 4.75rem); }
.section--tight { padding-block: clamp(1.5rem, 3vw, 2.5rem); }

.grid { display: grid; gap: var(--gutter); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(270px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.grid--4 { grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); }

.stack > * + * { margin-top: var(--stack-gap); }

.rule--full {
  width: 100%;
  height: 6px;
  border: 0;
  margin-block: clamp(2rem, 4.5vw, 3.25rem);
  background: linear-gradient(90deg,
    var(--royal) 0 58%,
    var(--gold) 58% 88%,
    var(--magenta) 88% 92%,
    var(--teal) 92% 100%);
}

/* ---------- 5. 站头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--ivory);
  border-bottom: 2px solid var(--navy);
  transition: background-color var(--t-base) var(--ease),
              box-shadow var(--t-base) var(--ease);
}

.site-header[data-stuck] {
  background: var(--white);
  box-shadow: 0 5px 0 rgba(20, 36, 92, .16);
}

.site-header__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: min(1240px, 100%);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.masthead {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: .5rem;
  width: 100%;
  padding: 1.65rem 0 1rem;
  text-align: center;
}

.masthead__eyebrow {
  font-family: var(--font-mono);
  font-size: .7rem;
  font-weight: 500;
  letter-spacing: .22em;
  color: var(--gray);
}

.masthead__brand {
  display: inline-flex;
  align-items: center;
  gap: .7rem;
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(2.35rem, 6.4vw, 3.5rem);
  line-height: 1;
  letter-spacing: .02em;
  color: var(--royal);
  transition: color var(--t-fast) var(--ease);
}

.masthead__brand:hover { color: var(--navy); }

.masthead__seal {
  display: grid;
  place-items: center;
  width: 2.1rem;
  height: 2.1rem;
  background: var(--gold);
  color: var(--navy);
  border: 2px solid var(--navy);
  box-shadow: 2px 2px 0 var(--navy);
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0;
}

.masthead__icp {
  padding: .18rem .5rem;
  font-family: var(--font-mono);
  font-size: .68rem;
  font-weight: 500;
  letter-spacing: .1em;
  color: var(--navy);
  background: rgba(201, 162, 39, .1);
  border: 2px solid var(--gold);
}

/* 导航 */
.site-nav { width: 100%; }

.site-nav__list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  border-top: 2px solid var(--navy);
}

.site-nav__item { display: flex; }

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: .85rem clamp(.85rem, 2.2vw, 1.5rem);
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1rem;
  color: var(--navy);
  transition: background-color var(--t-fast) var(--ease),
              color var(--t-fast) var(--ease);
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: clamp(.85rem, 2.2vw, 1.5rem);
  right: clamp(.85rem, 2.2vw, 1.5rem);
  bottom: .5rem;
  height: 3px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--t-base) var(--ease);
}

.site-nav__link:hover { background: rgba(30, 58, 138, .07); }

.site-nav__link:hover::after,
.site-nav__link:focus-visible::after { transform: scaleX(1); }

.site-nav__link[aria-current="page"] {
  background: var(--royal);
  color: var(--ivory);
}

.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--gold-hi);
}

/* 移动端开合按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: .65rem;
  width: 100%;
  min-height: 48px;
  padding: .65rem .9rem;
  background: var(--white);
  color: var(--navy);
  border: 2px solid var(--navy);
  border-bottom: 0;
  font-family: var(--font-mono);
  font-size: .76rem;
  font-weight: 700;
  letter-spacing: .12em;
}

.nav-toggle__bars {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 18px;
}

.nav-toggle__bars i {
  display: block;
  height: 2px;
  background: var(--navy);
  transition: transform var(--t-base) var(--ease),
              opacity var(--t-fast) var(--ease);
}

.site-header[data-open] .nav-toggle__bars i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars i:nth-child(2) { opacity: 0; }
.site-header[data-open] .nav-toggle__bars i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* 滚动进度 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 3px;
  overflow: hidden;
  pointer-events: none;
}

.scroll-progress__bar {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg,
    var(--gold) 0,
    var(--gold-hi) 55%,
    var(--magenta) 100%);
}

/* ---------- 6. 站脚 ---------- */
.site-footer {
  margin-top: auto;
  background-color: var(--navy);
  background-image: repeating-linear-gradient(135deg,
    rgba(201, 162, 39, .06) 0 2px,
    transparent 2px 9px);
  color: var(--ivory);
  border-top: 5px solid var(--gold);
}

.site-footer__inner {
  display: grid;
  gap: 2.25rem;
  width: min(1240px, 100%);
  margin-inline: auto;
  padding: clamp(2.25rem, 5vw, 3.5rem) var(--pad) clamp(1.5rem, 3vw, 2.25rem);
}

.footer-brand__line {
  font-family: var(--font-serif);
  font-weight: 900;
  font-size: clamp(1.3rem, 2.6vw, 1.65rem);
  line-height: 1.3;
  color: var(--gold-hi);
}

.footer-brand__note {
  margin-top: .7rem;
  max-width: 34ch;
  font-size: .92rem;
  line-height: 1.8;
  color: rgba(247, 245, 239, .74);
}

.footer-brand__mark {
  display: inline-block;
  margin-top: 1.1rem;
  padding: .22rem .55rem;
  background: var(--gold);
  color: var(--navy);
  border: 2px solid var(--navy);
  box-shadow: 3px 3px 0 rgba(0, 0, 0, .35);
  font-family: var(--font-mono);
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .3em;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1.5rem;
}

.footer-col__title {
  display: flex;
  align-items: center;
  gap: .45rem;
  margin-bottom: .5rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid rgba(201, 162, 39, .34);
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--gold-hi);
}

.footer-col__title::before {
  content: "";
  display: block;
  width: 8px;
  height: 8px;
  background: var(--gold);
}

.footer-col__link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: .95rem;
  color: rgba(247, 245, 239, .86);
  transition: color var(--t-fast) var(--ease),
              padding-left var(--t-fast) var(--ease);
}

.footer-col__link:hover {
  color: var(--gold-hi);
  padding-left: .35rem;
}

.footer-contact {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem 2rem;
  padding-top: 1.6rem;
  border-top: 1px solid rgba(201, 162, 39, .3);
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .06em;
  color: rgba(247, 245, 239, .82);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: .4rem 1.5rem;
  padding: 1.1rem var(--pad) 1.4rem;
  background: rgba(0, 0, 0, .26);
  border-top: 1px solid rgba(201, 162, 39, .3);
  text-align: center;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .05em;
  color: rgba(247, 245, 239, .72);
}

/* ---------- 7. 通用组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--royal);
}

.eyebrow::before {
  content: "";
  display: block;
  width: 22px;
  height: 3px;
  background: var(--gold);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  min-height: 48px;
  padding: .7rem 1.4rem;
  background: var(--gold);
  color: var(--navy);
  border: 2px solid var(--navy);
  box-shadow: var(--shadow);
  font-family: var(--font-mono);
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .1em;
  cursor: pointer;
  transition: transform var(--t-fast) var(--ease),
              box-shadow var(--t-fast) var(--ease),
              background-color var(--t-fast) var(--ease);
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-lg);
  background: var(--gold-hi);
}

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

.btn--ghost {
  background: var(--white);
  color: var(--navy);
}

.btn--ghost:hover { background: var(--ivory); }

.btn--dark {
  background: var(--royal);
  color: var(--ivory);
  box-shadow: 4px 4px 0 var(--gold);
}

.btn--dark:hover {
  background: var(--navy);
  box-shadow: 6px 6px 0 var(--gold);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .32rem .5rem;
  background: var(--white);
  color: var(--navy);
  border: 2px solid var(--navy);
  font-family: var(--font-mono);
  font-size: .68rem;
  font-weight: 700;
  letter-spacing: .08em;
  line-height: 1;
  white-space: nowrap;
}

.tag--magenta { background: var(--magenta); color: var(--white); }
.tag--teal { background: var(--teal); color: var(--white); }
.tag--brick { background: var(--brick); color: var(--white); }
.tag--gold { background: var(--gold); color: var(--navy); }

.stamp {
  display: inline-block;
  padding: .2rem .5rem;
  background: var(--gold);
  color: var(--navy);
  border: 2px solid var(--navy);
  box-shadow: 2px 2px 0 var(--navy);
  font-family: var(--font-mono);
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .1em;
  line-height: 1.5;
}

.card {
  padding: clamp(1.1rem, 3vw, 1.75rem);
  background: var(--white);
  border: 2px solid var(--navy);
  box-shadow: var(--shadow);
  transition: transform .16s var(--ease), box-shadow .16s var(--ease);
}

.card:hover {
  transform: translate(-4px, -4px);
  box-shadow: var(--shadow-lg);
}

.panel {
  padding: clamp(1rem, 2.6vw, 1.6rem);
  background: var(--white);
  border: 2px solid var(--navy);
}

.panel--ivory { background: var(--ivory); }

.panel--dark {
  background: var(--navy);
  color: var(--ivory);
  border-color: var(--gold);
}

.panel--dark h2,
.panel--dark h3 { color: var(--gold-hi); }

.count {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.9rem, 4.4vw, 3rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.02em;
  color: var(--royal);
}

/* 正文 */
.prose {
  max-width: 68ch;
  font-size: 1.02rem;
  line-height: 1.9;
  color: var(--ink);
}

.prose > * + * { margin-top: 1.05em; }
.prose h2 { margin-top: 2.1em; }
.prose h3 { margin-top: 1.7em; }

.prose a {
  color: var(--royal);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}

.prose a:hover { color: var(--magenta); }

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

.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: .45em; }

.prose strong { font-weight: 700; color: var(--navy); }

.prose blockquote {
  padding: .85rem 1.1rem;
  border-left: 4px solid var(--gold);
  background: var(--white);
  color: var(--gray);
}

/* 面包屑 */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--gray);
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
  align-items: center;
}

.breadcrumb__list li {
  display: flex;
  align-items: center;
  gap: .4rem;
}

.breadcrumb__list li + li::before {
  content: "/";
  color: var(--gold);
  font-weight: 700;
}

.breadcrumb__link {
  color: var(--royal);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

/* 图片容器 */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 2px solid var(--navy);
  box-shadow: var(--shadow);
  background: linear-gradient(135deg, var(--royal) 0%, var(--navy) 55%, #0B1636 100%);
  isolation: isolate;
}

.media-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .7;
  mix-blend-mode: screen;
  background-image: repeating-linear-gradient(118deg,
    rgba(240, 216, 122, .14) 0 1px,
    transparent 1px 6px);
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--bare { box-shadow: none; }

/* 标签页（纯 CSS，最多五组） */
.tabs { position: relative; display: block; }

.tabs__input {
  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;
}

.tabs__nav {
  display: flex;
  flex-wrap: wrap;
  border-bottom: 3px solid var(--navy);
}

.tabs__label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  margin: 0 3px -3px 0;
  padding: .7rem 1.15rem;
  background: var(--ivory);
  color: var(--navy);
  border: 2px solid var(--navy);
  border-bottom: 0;
  font-family: var(--font-mono);
  font-size: .74rem;
  font-weight: 700;
  letter-spacing: .1em;
  cursor: pointer;
  transition: background-color var(--t-fast) var(--ease),
              color var(--t-fast) var(--ease),
              transform var(--t-fast) var(--ease);
}

.tabs__label:hover {
  background: var(--white);
  transform: translateY(-2px);
}

.tabs__panels { padding-top: 1.25rem; }
.tabs__panel { display: none; }

.tabs__input:nth-of-type(1):checked ~ .tabs__nav .tabs__label:nth-child(1),
.tabs__input:nth-of-type(2):checked ~ .tabs__nav .tabs__label:nth-child(2),
.tabs__input:nth-of-type(3):checked ~ .tabs__nav .tabs__label:nth-child(3),
.tabs__input:nth-of-type(4):checked ~ .tabs__nav .tabs__label:nth-child(4),
.tabs__input:nth-of-type(5):checked ~ .tabs__nav .tabs__label:nth-child(5) {
  background: var(--royal);
  color: var(--ivory);
  box-shadow: inset 0 -4px 0 var(--gold);
}

.tabs__input:nth-of-type(1):checked ~ .tabs__panels > .tabs__panel:nth-child(1),
.tabs__input:nth-of-type(2):checked ~ .tabs__panels > .tabs__panel:nth-child(2),
.tabs__input:nth-of-type(3):checked ~ .tabs__panels > .tabs__panel:nth-child(3),
.tabs__input:nth-of-type(4):checked ~ .tabs__panels > .tabs__panel:nth-child(4),
.tabs__input:nth-of-type(5):checked ~ .tabs__panels > .tabs__panel:nth-child(5) {
  display: block;
}

.tabs__input:focus-visible ~ .tabs__nav .tabs__label {
  outline: 3px solid var(--gold);
  outline-offset: 2px;
}

/* 折叠问答 */
.faq { border-top: 2px solid var(--navy); }

.faq__item {
  background: var(--white);
  border-bottom: 2px solid var(--navy);
}

.faq__q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 56px;
  padding: .9rem 1rem;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--navy);
  cursor: pointer;
  list-style: none;
}

.faq__q::-webkit-details-marker { display: none; }

.faq__q::after {
  content: "+";
  flex: none;
  font-family: var(--font-mono);
  font-size: 1.2rem;
  color: var(--gold);
}

.faq__item[open] .faq__q { background: var(--ivory); }
.faq__item[open] .faq__q::after { content: "\2212"; }

.faq__a {
  padding: .2rem 1rem 1.2rem;
  font-size: .98rem;
  line-height: 1.85;
  color: var(--ink);
}

/* 显现 */
.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .45s var(--ease), transform .45s var(--ease);
}

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

/* ---------- 8. 响应式 ---------- */
@media (max-width: 900px) {
  .nav-toggle { display: flex; }

  .masthead {
    gap: .4rem;
    padding: 1.1rem 0 .85rem;
  }

  .masthead__eyebrow { display: none; }
  .masthead__brand { font-size: clamp(1.9rem, 8vw, 2.6rem); }

  .masthead__seal {
    width: 1.7rem;
    height: 1.7rem;
    font-size: .85rem;
  }

  .site-nav {
    width: 100%;
    visibility: hidden;
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height var(--t-base) var(--ease),
                opacity var(--t-fast) var(--ease);
  }

  .site-header[data-open] .site-nav {
    visibility: visible;
    max-height: 72vh;
    overflow-y: auto;
    opacity: 1;
    background: var(--white);
    border: 2px solid var(--navy);
    border-top: 0;
  }

  .site-nav__list {
    flex-direction: column;
    border-top: 0;
  }

  .site-nav__item { border-top: 1px solid rgba(30, 58, 138, .16); }
  .site-nav__item:first-child { border-top: 0; }

  .site-nav__link {
    justify-content: flex-start;
    width: 100%;
    padding: 1rem .9rem;
    font-size: 1.02rem;
  }

  .site-nav__link::after {
    left: .9rem;
    right: auto;
    width: 34px;
  }
}

@media (min-width: 880px) {
  .site-footer__inner {
    grid-template-columns: minmax(250px, 1fr) minmax(0, 1.9fr);
    align-items: start;
  }

  .footer-contact { grid-column: 1 / -1; }
}

@media (min-width: 901px) {
  .site-header[data-stuck] .site-header__inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
    padding-block: .5rem;
  }

  .site-header[data-stuck] .masthead {
    flex-direction: row;
    align-items: center;
    gap: .65rem;
    width: auto;
    padding: 0;
    text-align: left;
  }

  .site-header[data-stuck] .masthead__eyebrow { display: none; }

  .site-header[data-stuck] .masthead__brand { font-size: 1.35rem; }

  .site-header[data-stuck] .masthead__seal {
    width: 1.5rem;
    height: 1.5rem;
    font-size: .72rem;
    box-shadow: none;
  }

  .site-header[data-stuck] .masthead__icp {
    padding: .12rem .4rem;
    font-size: .62rem;
  }

  .site-header[data-stuck] .site-nav { width: auto; }

  .site-header[data-stuck] .site-nav__list {
    flex-wrap: nowrap;
    border-top: 0;
  }

  .site-header[data-stuck] .site-nav__link {
    min-height: 44px;
    padding: .5rem .7rem;
    font-size: .92rem;
  }

  .site-header[data-stuck] .site-nav__link::after {
    left: .7rem;
    right: .7rem;
    bottom: .35rem;
  }
}

/* ---------- 9. 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .card:hover,
  .btn:hover,
  .tabs__label:hover {
    transform: none;
  }

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

@media print {
  .site-header,
  .site-footer,
  .scroll-progress { display: none; }
}