/* ==========================================================================
   经典品牌站 · 共享样式 /assets/site.css
   框架式导航 + 非对称编辑部版式；深墨蓝基底，暖金与青瓷绿点缀
   ========================================================================== */

/* ---------- 1. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, address, dl, dd { 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 { border-collapse: collapse; width: 100%; }
[hidden] { display: none !important; }

/* ---------- 2. Tokens ---------- */
:root {
  --ink: #0B1B2B;
  --ink-2: #12263A;
  --steel: #1E3A5F;
  --gold: #D4A24C;
  --gold-lite: #F0D28A;
  --celadon: #5FA89A;
  --electric: #2CC9B7;
  --violet: #6B5FA8;
  --violet-lite: #A99FE0;
  --text: #F4F7FA;
  --text-2: #B8C4D0;
  --line: #2A4058;
  --bar-h: 68px;
  --rail-w: 104px;
  --gutter: clamp(18px, 4vw, 56px);
  --radius: 14px;
  --radius-lg: 22px;
  --font-heading: "Source Han Serif SC", "Noto Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --font-body: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --shadow-card: 0 22px 46px -30px rgba(0, 0, 0, .9);
}

/* ---------- 3. Base ---------- */
body {
  min-height: 100vh;
  padding-top: var(--bar-h);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--text);
  background-color: var(--ink);
  background-image:
    linear-gradient(180deg, rgba(18, 38, 58, .9), rgba(11, 27, 43, 0) 460px),
    repeating-linear-gradient(0deg, rgba(42, 64, 88, .26) 0 1px, transparent 1px 64px),
    repeating-linear-gradient(90deg, rgba(42, 64, 88, .18) 0 1px, transparent 1px 64px);
  background-attachment: scroll;
}
h1, h2, h3, h4 { font-family: var(--font-heading); font-weight: 800; line-height: 1.25; letter-spacing: .01em; }
h1 { font-size: clamp(34px, 6vw, 60px); }
h2 { font-size: clamp(26px, 3.4vw, 40px); }
h3 { font-size: clamp(20px, 2.2vw, 24px); }
p { color: var(--text); }
::selection { background: var(--gold); color: #14100A; }

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

#main-content {
  display: block;
  padding-top: clamp(16px, 2.4vw, 32px);
}

/* ---------- 4. Skip link ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 12px;
  z-index: 120;
  transform: translateY(-220%);
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--gold-lite);
  color: #14100A;
  font-weight: 700;
  font-size: 14px;
  transition: transform .16s ease;
}
.skip-link:focus { transform: translateY(0); }

/* ---------- 5. Header / 顶栏 ---------- */
.site-header { position: relative; z-index: 70; }

.header-bar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 70;
  height: var(--bar-h);
  background: rgba(11, 27, 43, .94);
  border-bottom: 1px solid var(--line);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}
.header-bar__inner {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  max-width: 1440px;
  height: 100%;
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.brand { display: flex; align-items: center; gap: 12px; min-width: 0; }
.brand__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  flex: none;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: linear-gradient(140deg, var(--steel), var(--ink-2));
  color: var(--gold-lite);
  font-size: 13px;
  letter-spacing: .06em;
}
.brand__text { display: flex; flex-direction: column; line-height: 1.28; min-width: 0; }
.brand__name {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: .04em;
  white-space: nowrap;
}
.brand__line {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--text-2);
  white-space: nowrap;
}
.brand--footer .brand__name { font-size: 20px; }
.brand--footer .brand__mark { width: 44px; height: 44px; font-size: 14px; }

.header-utility { display: none; }
.utility-link {
  padding: 6px 2px;
  border-bottom: 1px solid transparent;
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--text-2);
  transition: color .18s ease, border-color .18s ease;
}
.utility-link:hover, .utility-link:focus-visible { color: var(--electric); border-bottom-color: var(--electric); }

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .02em;
  white-space: nowrap;
  transition: transform .16s ease, background-color .16s ease, border-color .16s ease, color .16s ease;
}
.btn--gold {
  background: linear-gradient(140deg, var(--gold-lite), var(--gold));
  color: #17120A;
  border-color: rgba(240, 210, 138, .5);
}
.btn--gold:hover, .btn--gold:focus-visible { transform: translateY(-1px); background: linear-gradient(140deg, #FBE3A9, var(--gold-lite)); }
.btn--ghost {
  border-color: var(--line);
  background: rgba(30, 58, 95, .35);
  color: var(--text);
}
.btn--ghost:hover, .btn--ghost:focus-visible { border-color: var(--electric); color: var(--electric); }

.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(18, 38, 58, .6);
  color: var(--text-2);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
}
.nav-toggle:hover { color: var(--text); border-color: rgba(44, 201, 183, .55); }
.nav-toggle__bars { display: flex; flex-direction: column; gap: 4px; width: 18px; }
.nav-toggle__bars i {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform .18s ease, opacity .18s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ---------- 6. 导航（移动端浮层 / 桌面端左轨） ---------- */
.site-nav {
  position: fixed;
  top: var(--bar-h);
  left: 0;
  right: 0;
  z-index: 60;
  max-height: calc(100vh - var(--bar-h));
  overflow-y: auto;
  background: linear-gradient(180deg, var(--ink-2), var(--ink));
  border-bottom: 1px solid var(--line);
  visibility: hidden;
  opacity: 0;
  transform: translateY(-10px);
  transition: opacity .18s ease, transform .18s ease, visibility .18s ease;
}
.site-nav[data-open] { visibility: visible; opacity: 1; transform: translateY(0); }

.site-nav__caption {
  display: none;
  padding: 20px 8px 10px;
  text-align: center;
  font-size: 10px;
  letter-spacing: .28em;
  color: var(--text-2);
}
.site-nav__list { display: flex; flex-direction: column; padding: 6px 0 18px; }
.site-nav__item { border-bottom: 1px solid rgba(42, 64, 88, .6); }
.site-nav__item:first-child { border-top: 1px solid rgba(42, 64, 88, .6); }
.site-nav__link {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px var(--gutter);
  color: var(--text-2);
  font-size: 16px;
  transition: color .18s ease, background-color .18s ease, box-shadow .18s ease;
}
.site-nav__index { font-size: 11px; letter-spacing: .18em; color: var(--line); }
.site-nav__link:hover, .site-nav__link:focus-visible { color: var(--text); background: rgba(30, 58, 95, .32); }
.site-nav__link[aria-current="page"] {
  color: var(--gold-lite);
  background: rgba(30, 58, 95, .5);
  box-shadow: inset 3px 0 0 var(--gold);
}
.site-nav__link[aria-current="page"] .site-nav__index { color: var(--gold); }

/* ---------- 7. 阅读进度条 ---------- */
.scroll-progress {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  z-index: 80;
  background: rgba(42, 64, 88, .45);
  pointer-events: none;
}
.scroll-progress > span {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--celadon), var(--electric) 55%, var(--gold));
}

/* ---------- 8. 页脚 ---------- */
.site-footer {
  margin-top: clamp(72px, 10vw, 140px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, var(--ink-2), #08131F);
}
.site-footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 56px);
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding: clamp(40px, 6vw, 76px) var(--gutter) clamp(32px, 4vw, 52px);
}
.footer-brand { min-width: 0; }
.footer-tagline {
  margin-top: 16px;
  max-width: 34ch;
  font-size: 14px;
  color: var(--text-2);
}
.footer-col { min-width: 0; }
.footer-col__title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: 11px;
  letter-spacing: .24em;
  color: var(--celadon);
}
.footer-col__title::after {
  content: "";
  display: block;
  width: 28px;
  height: 1px;
  margin-top: 10px;
  background: var(--gold);
}
.footer-list { display: flex; flex-direction: column; gap: 10px; }
.footer-link {
  font-size: 15px;
  color: var(--text-2);
  transition: color .18s ease;
}
.footer-link:hover, .footer-link:focus-visible { color: var(--electric); }
.footer-link[aria-current="page"] { color: var(--gold-lite); }

.footer-contact { display: flex; flex-direction: column; gap: 14px; font-style: normal; }
.footer-contact__row { display: flex; flex-direction: column; gap: 2px; }
.footer-contact__label {
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--celadon);
}
.footer-contact__value {
  font-size: 15px;
  color: var(--text);
  word-break: break-word;
}

.site-footer__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding: 20px var(--gutter) 28px;
  border-top: 1px solid var(--line);
}
.footer-copy, .footer-note { font-size: 13px; color: var(--text-2); }
.footer-icp { font-size: 12px; letter-spacing: .08em; color: var(--text-2); }

/* ---------- 9. 通用版式组件 ---------- */
.wrap {
  width: 100%;
  max-width: 1180px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.section { padding-block: clamp(44px, 6.5vw, 92px); }
.section__head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(24px, 3vw, 44px);
  padding-top: 20px;
  border-top: 1px solid var(--line);
}
.section__title { font-size: clamp(26px, 3.2vw, 38px); }
.section__note { max-width: 56ch; font-size: 14px; color: var(--text-2); }
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .24em;
  color: var(--celadon);
  text-transform: uppercase;
}
.eyebrow::before { content: ""; width: 22px; height: 1px; background: var(--gold); }

.grid { display: grid; grid-template-columns: 1fr; gap: clamp(18px, 2.4vw, 32px); }

.breadcrumbs { font-size: 13px; }
.breadcrumbs__list { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.breadcrumbs__item { display: flex; align-items: center; gap: 8px; color: var(--text-2); }
.breadcrumbs__link { color: var(--text-2); transition: color .18s ease; }
.breadcrumbs__link:hover, .breadcrumbs__link:focus-visible { color: var(--electric); }
.breadcrumbs__sep { font-family: var(--font-mono); color: var(--line); }

.prose { max-width: 72ch; font-size: 17px; }
.prose > * + * { margin-top: 1.05em; }
.prose h2 { margin-top: 1.7em; font-size: clamp(24px, 2.8vw, 32px); }
.prose h3 { margin-top: 1.4em; }
.prose p, .prose li { color: var(--text-2); }
.prose strong { color: var(--gold-lite); }
.prose ul, .prose ol { display: flex; flex-direction: column; gap: 10px; }
.prose li { position: relative; padding-left: 24px; }
.prose li::before {
  content: "—";
  position: absolute;
  left: 0;
  font-family: var(--font-mono);
  color: var(--gold);
}

.mono { font-family: var(--font-mono); font-size: .9em; letter-spacing: .06em; }
.num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(34px, 5vw, 60px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--gold-lite);
}
.index-num { font-family: var(--font-mono); font-size: 12px; letter-spacing: .2em; color: var(--celadon); }
.muted { color: var(--text-2); }

/* ---------- 10. 卡片 / 标签 ---------- */
.card {
  position: relative;
  padding: clamp(20px, 2.4vw, 30px);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, rgba(30, 58, 95, .55), rgba(18, 38, 58, .92));
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: radial-gradient(120% 90% at 92% 4%, rgba(212, 162, 76, .14), transparent 60%);
  pointer-events: none;
}
.card:hover { transform: translateY(-2px); border-color: rgba(44, 201, 183, .45); box-shadow: var(--shadow-card); }
.card__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--celadon);
}
.card__title { margin: 10px 0 8px; font-size: clamp(20px, 2.2vw, 24px); }
.card__body { font-size: 15px; color: var(--text-2); }
.card__foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px dashed var(--line);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(11, 27, 43, .6);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--text-2);
}
.tag--gold { color: var(--gold-lite); border-color: rgba(212, 162, 76, .55); background: rgba(212, 162, 76, .12); }
.tag--celadon { color: var(--celadon); border-color: rgba(95, 168, 154, .55); background: rgba(95, 168, 154, .12); }
.tag--violet { color: var(--violet-lite); border-color: rgba(107, 95, 168, .6); background: rgba(107, 95, 168, .16); }
.tag--steel { color: var(--text); border-color: rgba(30, 58, 95, .9); background: rgba(30, 58, 95, .55); }

/* ---------- 11. 视觉容器（页面阶段放 CSS/SVG 图形或图片占位） ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(150deg, rgba(30, 58, 95, .72), rgba(11, 27, 43, .94));
}
.media-frame__inner { position: relative; aspect-ratio: 16 / 10; }
.media-frame__inner > img,
.media-frame__inner > svg,
.media-frame__inner > canvas { width: 100%; height: 100%; object-fit: cover; }
.media-frame__inner::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .55;
  background-image:
    repeating-linear-gradient(0deg, rgba(42, 64, 88, .4) 0 1px, transparent 1px 22px),
    repeating-linear-gradient(90deg, rgba(42, 64, 88, .4) 0 1px, transparent 1px 22px);
}
.media-frame__caption {
  padding: 12px 16px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--text-2);
}
.media-frame--wide .media-frame__inner { aspect-ratio: 21 / 9; }
.media-frame--tall .media-frame__inner { aspect-ratio: 4 / 5; }

/* ---------- 12. 主题筛选 ---------- */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: clamp(20px, 3vw, 32px);
}
.filter-btn {
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(18, 38, 58, .72);
  color: var(--text-2);
  font-size: 14px;
  letter-spacing: .02em;
  transition: color .16s ease, background-color .16s ease, border-color .16s ease;
}
.filter-btn:hover, .filter-btn:focus-visible { color: var(--text); border-color: rgba(44, 201, 183, .55); }
.filter-btn[aria-pressed="true"] {
  color: #06211E;
  font-weight: 600;
  border-color: transparent;
  background: linear-gradient(140deg, var(--electric), var(--celadon));
}
.filter-btn.is-active { color: #06211E; background: linear-gradient(140deg, var(--electric), var(--celadon)); }
.filter-item { transition: opacity .16s ease; }

/* ---------- 13. 滚动渐入 ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .5s ease, transform .5s ease;
}
.js [data-reveal].is-visible { opacity: 1; transform: none; }

/* ---------- 14. 断点 ---------- */
@media (min-width: 640px) {
  .site-footer__grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer-col--contact { grid-column: 1 / -1; }
}

@media (min-width: 900px) {
  .header-utility { display: flex; align-items: center; gap: 20px; margin-left: auto; }
  .header-actions { margin-left: 0; }
  .grid--2-10 { grid-template-columns: 2fr 10fr; }
  .grid--3-9 { grid-template-columns: 3fr 9fr; }
  .grid--4-8 { grid-template-columns: 4fr 8fr; }
  .grid--halves { grid-template-columns: 1fr 1fr; }
}

@media (min-width: 1024px) {
  body { padding-left: var(--rail-w); }
  .header-bar { left: var(--rail-w); }
  .nav-toggle { display: none; }

  .site-nav {
    top: var(--bar-h);
    bottom: 0;
    left: 0;
    right: auto;
    width: var(--rail-w);
    height: auto;
    max-height: none;
    display: flex;
    flex-direction: column;
    border-bottom: 0;
    border-right: 1px solid var(--line);
    background: linear-gradient(180deg, var(--ink-2) 0%, #08131F 100%);
    visibility: visible;
    opacity: 1;
    transform: none;
    overflow-y: auto;
  }
  .site-nav__caption { display: block; }
  .site-nav__list { padding: 0 0 28px; }
  .site-nav__item { border-bottom: 0; }
  .site-nav__item:first-child { border-top: 0; }
  .site-nav__link {
    flex-direction: column;
    align-items: center;
    gap: 10px;
    padding: 14px 6px;
    border-left: 2px solid transparent;
  }
  .site-nav__label {
    writing-mode: vertical-rl;
    font-size: 13px;
    letter-spacing: .22em;
  }
  .site-nav__link:hover, .site-nav__link:focus-visible { background: rgba(30, 58, 95, .32); }
  .site-nav__link[aria-current="page"] {
    box-shadow: none;
    border-left-color: var(--gold);
    background: rgba(30, 58, 95, .5);
  }
  .site-footer__grid { grid-template-columns: 1.6fr .8fr .8fr 1.2fr; }
  .footer-col--contact { grid-column: auto; }
}

@media (min-width: 1280px) {
  :root { --rail-w: 116px; }
}

@media (max-width: 639px) {
  .header-cta { display: none; }
  .brand__line { display: none; }
}

/* ---------- 15. 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;
  }
  .js [data-reveal] { opacity: 1 !important; transform: none !important; }
  .card:hover { transform: none; }
  .btn--gold:hover { transform: none; }
}