/* ==========================================================================
   9393 主页 · 共享站点样式 /assets/site.css
   数字档案阅览室：纸白阅读底 + 深海蓝落款 + 琥珀金版本标记 + 青瓷绿状态
   ========================================================================== */

*, *::before, *::after { box-sizing: border-box; }

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

body, h1, h2, h3, h4, h5, p, ul, ol, figure, blockquote, dl, dd { 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; }
a { color: inherit; }

:root {
  /* 色板 */
  --blue-950: #071626;
  --blue-900: #0B1E33;
  --blue-700: #173A5A;
  --blue-500: #3E6B8C;
  --celadon: #5E8C7A;
  --celadon-pale: #DCE8E2;
  --amber: #B9852F;
  --amber-deep: #7A5418;
  --grey-100: #F4F1EA;
  --grey-200: #E4DFD4;
  --paper: #FBFAF7;
  --ink: #18202A;
  --ink-dim: #4B5665;
  --on-dark: #FBFAF7;
  --on-dark-dim: #A7B6C4;

  /* 语义 */
  --line: #E4DFD4;
  --line-dark: rgba(251, 250, 247, 0.14);
  --surface: #F4F1EA;
  --radius-pill: 999px;
  --radius-card: 14px;
  --container: 1200px;
  --gutter: 24px;
  --shadow-sm: 0 1px 2px rgba(7, 22, 38, 0.06), 0 8px 22px -16px rgba(7, 22, 38, 0.45);
  --shadow-md: 0 2px 6px rgba(7, 22, 38, 0.08), 0 22px 46px -28px rgba(7, 22, 38, 0.55);

  /* 字体 */
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Heiti SC", sans-serif;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", "Courier New", monospace;
}

/* ------------------------------ 基础排版 ------------------------------ */
body {
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--font-serif);
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5 {
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.012em;
  color: var(--blue-900);
}

h1 { font-size: clamp(28px, 4vw, 40px); }
h2 { font-size: clamp(22px, 3vw, 32px); }
h3 { font-size: clamp(17px, 2vw, 24px); }
h4 { font-size: 16px; }

p { text-wrap: pretty; }

strong, b { font-weight: 700; color: var(--blue-900); }

::selection { background: var(--celadon-pale); color: var(--blue-950); }

:focus-visible {
  outline: 2px solid var(--celadon);
  outline-offset: 3px;
  border-radius: 4px;
}
.site-footer :focus-visible { outline-color: var(--amber); }

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

/* ------------------------------ 通用容器与章节 ------------------------------ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(44px, 6vw, 76px); }

.section-head {
  display: grid;
  gap: 10px;
  margin-bottom: clamp(24px, 3vw, 36px);
}

.section-number {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--amber-deep);
}

.section-title { font-size: clamp(22px, 3vw, 32px); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--amber-deep);
}

.lead {
  font-size: clamp(16px, 1.6vw, 18px);
  line-height: 1.85;
  color: var(--ink-dim);
}

.divider {
  height: 1px;
  border: 0;
  background: var(--line);
  margin-block: clamp(28px, 4vw, 44px);
}

/* ------------------------------ 面包屑 ------------------------------ */
.breadcrumb { padding-block: 18px 0; }

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-dim);
}

.breadcrumb li { display: flex; align-items: center; gap: 8px; }
.breadcrumb li + li::before { content: "/"; color: var(--blue-500); opacity: 0.7; }
.breadcrumb a { text-decoration: none; transition: color 0.18s ease; }
.breadcrumb a:hover { color: var(--blue-900); text-decoration: underline; }
.breadcrumb [aria-current="page"] { color: var(--blue-900); font-weight: 600; }

/* ------------------------------ 按钮与标签 ------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 22px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  line-height: 1.3;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
}

.btn--primary { background-color: var(--blue-900); color: var(--on-dark); }
.btn--primary:hover { background-color: var(--blue-700); transform: translateY(-1px); }

.btn--ghost { background-color: transparent; border-color: var(--line); color: var(--blue-900); }
.btn--ghost:hover { background-color: var(--grey-100); border-color: var(--blue-900); }

.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background-color: var(--grey-100);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--blue-700);
}

.pill--accent {
  background-color: rgba(185, 133, 47, 0.12);
  border-color: rgba(185, 133, 47, 0.42);
  color: var(--amber-deep);
}

/* ------------------------------ 卡片与网格 ------------------------------ */
.card {
  background-color: var(--grey-100);
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  padding: clamp(18px, 2.4vw, 26px);
  box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
}

.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); background-color: #F7F4EE; }

.card-grid {
  display: grid;
  gap: clamp(16px, 2vw, 22px);
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 4fr) minmax(0, 7fr);
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}

.note-band {
  border-left: 3px solid var(--celadon);
  background-color: var(--celadon-pale);
  border-radius: 0 10px 10px 0;
  padding: 16px 20px;
  font-size: 15px;
  color: var(--blue-900);
}

/* ------------------------------ 正文长文 ------------------------------ */
.prose { max-width: 68ch; font-size: 16px; line-height: 1.85; }
.prose > * + * { margin-top: 1.1em; }
.prose h2 { font-size: clamp(20px, 2.4vw, 26px); margin-top: 1.8em; }
.prose h3 { font-size: 18px; margin-top: 1.6em; }
.prose ul, .prose ol { padding-left: 1.35em; }
.prose ul { list-style: square; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: 0.4em; }
.prose a { color: var(--blue-700); text-underline-offset: 3px; }
.prose a:hover { color: var(--amber-deep); }
.prose strong { color: var(--blue-900); }

/* ------------------------------ 图片容器基础规则 ------------------------------ */
.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  background-color: var(--grey-100);
  background-image: linear-gradient(135deg, #F1EDE4 0%, #E7E1D5 100%);
  aspect-ratio: 16 / 10;
  box-shadow: var(--shadow-sm);
}

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

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--slant { transform: rotate(-1.4deg); }

.media-frame__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--ink-dim);
}

/* ------------------------------ 标签页组件 ------------------------------ */
.tabs {
  border: 1px solid var(--line);
  border-radius: var(--radius-card);
  background-color: var(--paper);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 10px;
  background-color: var(--grey-100);
  border-bottom: 1px solid var(--line);
}

.tab {
  appearance: none;
  -webkit-appearance: none;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background-color: transparent;
  padding: 8px 16px;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  color: var(--blue-900);
  cursor: pointer;
  transition: background-color 0.18s ease, color 0.18s ease, border-color 0.18s ease;
}

.tab:hover { background-color: var(--paper); border-color: var(--line); }

.tab[aria-selected="true"] {
  background-color: var(--blue-900);
  border-color: var(--blue-900);
  color: var(--on-dark);
}

.tab-panel { padding: clamp(18px, 2.4vw, 26px); }
.tab-panel[hidden] { display: none; }

/* ------------------------------ 滚动显现 ------------------------------ */
[data-reveal] {
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

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

:root:not(.js) [data-reveal] { opacity: 1; transform: none; }

/* ==========================================================================
   页头：双浮岛胶囊导航 + 阅读进度尺
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background-color: rgba(251, 250, 247, 0.88);
  -webkit-backdrop-filter: blur(14px) saturate(1.15);
  backdrop-filter: blur(14px) saturate(1.15);
  border-bottom: 1px solid var(--line);
  transition: box-shadow 0.25s ease;
}

.site-header[data-scrolled] { box-shadow: 0 14px 32px -26px rgba(7, 22, 38, 0.6); }

.skip-link {
  position: absolute;
  left: var(--gutter);
  top: -80px;
  z-index: 200;
  padding: 10px 18px;
  border-radius: var(--radius-pill);
  background-color: var(--blue-950);
  color: var(--on-dark);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: top 0.18s ease;
}

.skip-link:focus { top: 10px; }

.header-shell {
  max-width: var(--container);
  margin-inline: auto;
  padding: 10px var(--gutter);
}

.header-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

/* 品牌浮岛 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 6px 16px 6px 6px;
  border-radius: var(--radius-pill);
  background-color: var(--blue-900);
  color: var(--on-dark);
  text-decoration: none;
  box-shadow: var(--shadow-sm);
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.brand:hover { background-color: var(--blue-700); transform: translateY(-1px); }

.brand-mark {
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  flex: none;
  border-radius: 50%;
  background-color: var(--amber);
  color: var(--blue-950);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand-text { display: flex; flex-direction: column; line-height: 1.15; }

.brand-name {
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand-meta {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--celadon-pale);
}

/* 导航浮岛 */
.nav-island {
  background-color: var(--grey-100);
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  padding: 5px;
  box-shadow: var(--shadow-sm);
}

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

.nav-link {
  display: block;
  padding: 8px 15px;
  border-radius: var(--radius-pill);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--blue-900);
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 0.18s ease, color 0.18s ease, box-shadow 0.18s ease;
}

.nav-link:hover {
  background-color: var(--paper);
  color: var(--blue-700);
  box-shadow: inset 0 0 0 1px var(--line);
}

.nav-link[aria-current="page"] {
  background-color: var(--blue-900);
  color: var(--on-dark);
  box-shadow: none;
}

/* 行动区 */
.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-left: auto;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  background-color: var(--amber);
  color: var(--blue-950);
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  line-height: 1.3;
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 1px 2px rgba(7, 22, 38, 0.14);
  transition: background-color 0.18s ease, transform 0.18s ease, box-shadow 0.18s ease;
}

.header-cta:hover {
  background-color: #C99436;
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.header-cta span[aria-hidden="true"] { font-family: var(--font-mono); font-size: 13px; }

/* 移动菜单按钮 */
.nav-toggle {
  display: none;
  place-items: center;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background-color: var(--grey-100);
  cursor: pointer;
  transition: background-color 0.18s ease, border-color 0.18s ease;
}

.nav-toggle:hover { background-color: var(--paper); border-color: var(--blue-500); }

.nav-toggle-bars {
  position: relative;
  display: block;
  width: 18px;
  height: 12px;
}

.nav-toggle-bars span {
  position: absolute;
  left: 0;
  width: 100%;
  height: 1.5px;
  border-radius: 2px;
  background-color: var(--blue-900);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle-bars span:nth-child(1) { top: 0; }
.nav-toggle-bars span:nth-child(2) { top: 5px; }
.nav-toggle-bars span:nth-child(3) { top: 10px; }

.site-header[data-open] .nav-toggle-bars span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.site-header[data-open] .nav-toggle-bars span:nth-child(2) { opacity: 0; }
.site-header[data-open] .nav-toggle-bars span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

/* 阅读进度尺 */
.scroll-meter {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 3px;
  overflow: hidden;
  pointer-events: none;
}

.scroll-meter-fill {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background-image: linear-gradient(90deg, var(--amber) 0%, var(--celadon) 100%);
}

/* ==========================================================================
   页脚：四栏信息 + 横向认证证书带 + 备案落款
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 104px);
  background-color: var(--blue-950);
  color: var(--on-dark);
  font-family: var(--font-sans);
}

.footer-rule {
  height: 2px;
  background-image: linear-gradient(90deg, var(--amber) 0%, var(--amber) 18%, var(--celadon) 45%, var(--blue-700) 100%);
}

.footer-shell {
  max-width: var(--container);
  margin-inline: auto;
  padding: clamp(36px, 5vw, 56px) var(--gutter) 28px;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.4fr;
  gap: 32px 36px;
}

.footer-brand { display: grid; gap: 12px; align-content: start; justify-items: start; }

.footer-name {
  font-family: var(--font-sans);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--on-dark);
}

.footer-tagline {
  font-size: 14px;
  line-height: 1.7;
  color: var(--on-dark-dim);
}

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

.footer-col-title {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--celadon-pale);
}

.footer-col-title::before {
  content: "";
  width: 14px;
  height: 1px;
  flex: none;
  background-color: var(--amber);
}

.footer-links { display: grid; gap: 4px; }

.footer-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--on-dark);
  text-decoration: none;
  transition: color 0.18s ease, transform 0.18s ease;
}

.footer-link::before {
  content: "";
  width: 4px;
  height: 4px;
  flex: none;
  border-radius: 50%;
  background-color: var(--celadon);
  opacity: 0.75;
  transition: background-color 0.18s ease;
}

.footer-link:hover { color: var(--amber); transform: translateX(2px); }
.footer-link:hover::before { background-color: var(--amber); }

.footer-contact { display: grid; gap: 12px; }

.contact-line {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  color: var(--on-dark);
}

.contact-key {
  font-family: var(--font-sans);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--on-dark-dim);
}

.contact-value { word-break: break-all; }

.contact-note {
  font-family: var(--font-sans);
  font-size: 12.5px;
  line-height: 1.75;
  color: var(--on-dark-dim);
  max-width: 34ch;
}

.copy-btn {
  appearance: none;
  -webkit-appearance: none;
  padding: 3px 9px;
  border: 1px solid rgba(251, 250, 247, 0.24);
  border-radius: var(--radius-pill);
  background-color: transparent;
  font-family: var(--font-sans);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--celadon-pale);
  cursor: pointer;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

.copy-btn:hover { color: var(--amber); border-color: var(--amber); background-color: rgba(185, 133, 47, 0.1); }

/* 认证证书带 */
.footer-cert {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.45fr);
  gap: clamp(18px, 3vw, 32px);
  align-items: center;
  margin-top: clamp(30px, 4vw, 44px);
  padding: clamp(18px, 2.4vw, 24px);
  border: 1px solid rgba(185, 133, 47, 0.38);
  border-radius: var(--radius-card);
  background-image: linear-gradient(120deg, rgba(185, 133, 47, 0.12) 0%, rgba(94, 140, 122, 0.07) 100%);
}

.cert { display: grid; gap: 6px; }

.cert-badge { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }

.cert-value {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3vw, 30px);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--amber);
}

.cert-label {
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--celadon-pale);
}

.cert-sub {
  font-family: var(--font-sans);
  font-size: 13px;
  line-height: 1.7;
  color: var(--on-dark-dim);
}

.cert-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  padding-top: 16px;
  border-top: 1px solid var(--line-dark);
}

.cert-list li { display: grid; gap: 4px; min-width: 0; }

.cert-key {
  font-family: var(--font-sans);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--on-dark-dim);
}

.cert-val {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  color: var(--on-dark);
  word-break: break-word;
}

/* 落款底栏 */
.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 14px 24px;
  margin-top: clamp(24px, 3vw, 36px);
  padding-top: 20px;
  border-top: 1px solid var(--line-dark);
  font-size: 12.5px;
  color: var(--on-dark-dim);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 18px;
}

.footer-meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.01em;
  word-break: break-all;
}

.to-top {
  appearance: none;
  -webkit-appearance: none;
  padding: 8px 16px;
  border: 1px solid rgba(251, 250, 247, 0.24);
  border-radius: var(--radius-pill);
  background-color: transparent;
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--on-dark);
  cursor: pointer;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

.to-top:hover { color: var(--amber); border-color: var(--amber); background-color: rgba(185, 133, 47, 0.1); }

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 1024px) {
  .nav-toggle { display: grid; }

  .nav-island {
    display: none;
    position: absolute;
    top: calc(100% + 14px);
    left: 0;
    right: 0;
    z-index: 3;
    padding: 10px;
    border-radius: 18px;
    background-color: var(--paper);
    box-shadow: var(--shadow-md);
  }

  .site-header[data-open] .nav-island {
    display: block;
    animation: nav-island-in 0.18s ease-out both;
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 4px; }

  .nav-link { padding: 12px 14px; border-radius: 12px; font-size: 15px; }

  .nav-link:hover { box-shadow: none; background-color: var(--grey-100); }

  .footer-top { grid-template-columns: 1fr 1fr; gap: 30px 28px; }
  .footer-cert { grid-template-columns: 1fr; }
}

@keyframes nav-island-in {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

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

@media (max-width: 700px) {
  :root { --gutter: 18px; }

  .header-shell { padding: 8px var(--gutter); }
  .brand { padding: 5px 13px 5px 5px; gap: 8px; }
  .brand-mark { width: 27px; height: 27px; font-size: 11px; }
  .brand-name { font-size: 14px; }
  .brand-meta { font-size: 9px; letter-spacing: 0.06em; }
  .header-cta { padding: 9px 14px; font-size: 13px; }

  .footer-top { grid-template-columns: 1fr; }
  .cert-list { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 460px) {
  .brand-meta { display: none; }
  .brand-name { font-size: 13.5px; }
  .header-cta { padding: 9px 12px; font-size: 12.5px; gap: 5px; }
  .header-actions { gap: 6px; }
  .nav-toggle { width: 38px; height: 38px; }
  .cert-list { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

/* ==========================================================================
   减弱动效
   ========================================================================== */
@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] { opacity: 1 !important; transform: none !important; }
  .card:hover, .brand:hover, .header-cta:hover, .footer-link:hover { transform: none; }
  .scroll-meter-fill { transition: none !important; }
}