/* ==========================================================================
   万博登录入口 · 中国区站点
   /assets/site.css — 共享外壳与基础组件
   ========================================================================== */

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

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

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

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

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

[hidden] { display: none !important; }

/* ---------- 2. 设计变量 ---------- */
:root {
  /* 色彩体系 */
  --paper: #F7F2E8;
  --card: #FFFDF8;
  --ink: #0B1B34;
  --ink-2: #14294A;
  --signal: #FF6A1F;
  --signal-deep: #E85A12;
  --signal-soft: #FFE0CD;
  --line: #D9E0E4;
  --muted: #6E7A85;
  --pass: #1F7A68;
  --warn: #B23A28;

  /* 字体栈 */
  --font-display: "Archivo Narrow", "Arial Narrow", "Helvetica Neue Condensed",
    "PingFang SC", "HarmonyOS Sans", "Microsoft YaHei", sans-serif;
  --font-body: "Source Han Sans SC", "Noto Sans SC", "PingFang SC",
    "HarmonyOS Sans", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular,
    Menlo, Consolas, "Courier New", monospace;

  /* 度量 */
  --gutter: clamp(16px, 4.5vw, 40px);
  --wrap: 1240px;
  --ease: cubic-bezier(.22, .68, .24, 1);
  --hair: 1px solid var(--line);
  --shade: 0 18px 40px -30px rgba(11, 27, 52, .45);
  --shade-top: 0 14px 34px -28px rgba(11, 27, 52, .6);
}

/* ---------- 3. 中文排版基线 ---------- */
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  font-weight: 400;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

@media (min-width: 900px) {
  body { font-size: 17px; }
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 800;
  font-stretch: condensed;
  letter-spacing: -.02em;
  line-height: 1.1;
  color: var(--ink);
  text-wrap: balance;
}

h1 { font-size: clamp(32px, 5vw, 58px); }
h2 { font-size: clamp(24px, 3.2vw, 36px); }
h3 { font-size: clamp(19px, 2.2vw, 24px); letter-spacing: -.01em; }
h4 { font-size: 17px; letter-spacing: 0; }

p { max-width: 38em; }

a { color: var(--ink-2); }

strong { font-weight: 700; }

code, kbd, samp {
  font-family: var(--font-mono);
  font-size: .92em;
  font-variant-numeric: tabular-nums;
}

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

/* ---------- 4. 布局容器 ---------- */
.wrap {
  width: min(100% - var(--gutter) * 2, var(--wrap));
  margin-inline: auto;
}

.wrap--narrow {
  width: min(100% - var(--gutter) * 2, 780px);
  margin-inline: auto;
}

.prose p + p { margin-top: 1.1em; }
.prose p { max-width: 44em; }

.grid {
  display: grid;
  gap: clamp(14px, 1.8vw, 22px);
}

.grid--3 {
  grid-template-columns: repeat(auto-fit, minmax(min(260px, 100%), 1fr));
}

.grid--2 {
  grid-template-columns: repeat(auto-fit, minmax(min(320px, 100%), 1fr));
}

/* ---------- 5. 索引与标签 ---------- */
.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .26em;
  text-transform: uppercase;
  color: var(--signal);
}

.index-code {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .14em;
  text-transform: uppercase;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  text-align: right;
}

.tag {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  padding: 5px 10px;
  background: var(--signal-soft);
  color: #8A3208;
  border: 1px solid rgba(255, 106, 31, .28);
}

.tag--pass { background: rgba(31, 122, 104, .1); color: var(--pass); border-color: rgba(31, 122, 104, .3); }
.tag--warn { background: rgba(178, 58, 40, .08); color: var(--warn); border-color: rgba(178, 58, 40, .3); }

/* ---------- 6. 章节头 ---------- */
.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 20px;
  padding-bottom: 14px;
  margin-bottom: clamp(20px, 3vw, 34px);
  border-bottom: 1px solid var(--ink);
}

.section-head h2 { font-size: clamp(22px, 3vw, 34px); }
.section-head .index-code { margin-left: auto; }

/* ---------- 7. 卡片 ---------- */
.card {
  background: var(--card);
  border: var(--hair);
  padding: clamp(18px, 2.4vw, 28px);
}

.card--ink {
  background: var(--ink);
  border-color: var(--ink);
  color: #D9E2ED;
}

.card--ink h2,
.card--ink h3,
.card--ink h4 { color: #FFFFFF; }

.card--ink .index-code,
.card--ink .eyebrow { color: #8FA0B3; }

.card--signal {
  background: var(--signal-soft);
  border-color: rgba(255, 106, 31, .3);
}

.card-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

/* ---------- 8. 按钮与筛选 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  line-height: 1;
  padding: 15px 26px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--card);
  text-decoration: none;
  cursor: pointer;
  transition: background-color .18s var(--ease), color .18s var(--ease),
    border-color .18s var(--ease);
}

.btn:hover { background: var(--ink-2); border-color: var(--ink-2); color: #fff; }

.btn--signal {
  background: var(--signal);
  border-color: var(--signal);
  color: #0B1B34;
}

.btn--signal:hover {
  background: var(--signal-deep);
  border-color: var(--signal-deep);
  color: #0B1B34;
}

.btn--ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line);
}

.btn--ghost:hover {
  background: transparent;
  color: var(--signal-deep);
  border-color: var(--signal);
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 10px;
  background: var(--card);
  border: var(--hair);
}

.chip {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  padding: 8px 14px;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink-2);
  cursor: pointer;
  transition: background-color .12s var(--ease), color .12s var(--ease),
    border-color .12s var(--ease);
}

.chip:hover { border-color: var(--signal); color: var(--signal-deep); }

.chip[aria-pressed="true"] {
  background: var(--signal);
  border-color: var(--signal);
  color: #0B1B34;
  font-weight: 700;
}

/* ---------- 9. 参数表 ---------- */
.param-table {
  font-size: 15px;
  background: var(--card);
}

.param-table caption {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  text-align: left;
  padding: 0 0 10px;
}

.param-table th,
.param-table td {
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
}

.param-table thead th {
  position: sticky;
  top: 0;
  z-index: 2;
  background: var(--card);
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  border-bottom: 1px solid var(--ink);
}

.param-table tbody tr:nth-child(even) { background: rgba(217, 224, 228, .34); }
.param-table tbody tr:hover { background: var(--signal-soft); }

/* ---------- 10. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--muted);
}

.breadcrumb li { display: flex; align-items: center; }

.breadcrumb li + li::before {
  content: "/";
  margin-inline: 9px;
  color: var(--line);
}

.breadcrumb a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid var(--line);
}

.breadcrumb a:hover { color: var(--signal-deep); border-color: var(--signal); }

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

/* ---------- 11. 图片容器基础规则 ---------- */
.media-frame {
  position: relative;
  background: var(--card);
  border: var(--hair);
  overflow: hidden;
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 7px;
  border: 1px solid rgba(11, 27, 52, .07);
  pointer-events: none;
}

.media-frame > img,
.media-frame > svg,
.media-frame > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 9;
  background: linear-gradient(140deg, #EDF1F4 0%, #F7F2E8 100%);
}

.media-frame--tall > img,
.media-frame--tall > svg,
.media-frame--tall > picture > img { aspect-ratio: 3 / 4; }

.media-frame--square > img,
.media-frame--square > svg,
.media-frame--square > picture > img { aspect-ratio: 1 / 1; }

.media-frame--wide > img,
.media-frame--wide > svg,
.media-frame--wide > picture > img { aspect-ratio: 21 / 9; }

.media-frame--fit > img,
.media-frame--fit > svg { object-fit: contain; padding: 14px; }

.media-cap {
  padding-top: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--muted);
}

/* ---------- 12. 跳过链接 ---------- */
.skip-link {
  position: absolute;
  top: 10px;
  left: 50%;
  z-index: 900;
  transform: translate(-50%, -180%);
  padding: 10px 20px;
  background: var(--ink);
  color: var(--card);
  border: 1px solid var(--ink);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  text-decoration: none;
  transition: transform .18s var(--ease);
}

.skip-link:focus { transform: translate(-50%, 0); }

/* ---------- 13. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--paper);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .2s var(--ease);
}

.site-header.is-condensed { box-shadow: var(--shade-top); }

.header-inner {
  position: relative;
  width: min(100% - var(--gutter) * 2, var(--wrap));
  margin-inline: auto;
  padding-block: clamp(14px, 2vw, 24px) 0;
  transition: padding-block .2s var(--ease);
}

.masthead {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 6px;
  padding-bottom: clamp(12px, 1.6vw, 18px);
  transition: padding-bottom .2s var(--ease), gap .2s var(--ease);
}

.masthead-kicker {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .26em;
  text-transform: uppercase;
  color: var(--muted);
}

.masthead-brand {
  display: inline-flex;
  align-items: baseline;
  gap: .16em;
  font-family: var(--font-display);
  font-weight: 800;
  font-stretch: condensed;
  font-size: clamp(30px, 5.2vw, 54px);
  line-height: .94;
  letter-spacing: -.02em;
  color: var(--ink);
  text-decoration: none;
  transition: font-size .2s var(--ease);
}

.brand-suffix {
  color: var(--signal);
  transition: color .18s var(--ease);
}

.masthead-brand:hover .brand-suffix { color: var(--signal-deep); }

.masthead-line {
  font-size: 14px;
  letter-spacing: .06em;
  color: var(--muted);
}

/* 右侧窄索引条 */
.index-rail {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 18px;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .06em;
}

.rail-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--muted);
  text-decoration: none;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.rail-item:hover { color: var(--ink); border-color: var(--signal); }

.rail-code {
  color: var(--signal);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.utility-link {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--ink);
  text-decoration: none;
  padding: 6px 12px;
  border: 1px solid var(--ink);
  transition: background-color .18s var(--ease), color .18s var(--ease);
}

.utility-link:hover { background: var(--ink); color: var(--paper); }

@media (min-width: 1080px) {
  .index-rail {
    position: absolute;
    top: 6px;
    right: 0;
    flex-direction: column;
    align-items: flex-end;
    justify-content: flex-start;
    gap: 6px;
    margin-top: 0;
    text-align: right;
  }
}

/* 移动端目录按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  padding: 9px 14px;
  cursor: pointer;
  transition: border-color .18s var(--ease), color .18s var(--ease);
}

.nav-toggle:hover { border-color: var(--ink); }

.nav-toggle-icon {
  display: inline-flex;
  flex-direction: column;
  gap: 3px;
  width: 16px;
}

.nav-toggle-icon span {
  display: block;
  height: 1.5px;
  background: currentColor;
  transition: transform .18s var(--ease), opacity .18s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:nth-child(1) { transform: translateY(4.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle-icon span:nth-child(3) { transform: translateY(-4.5px) rotate(-45deg); }

/* 居中刊头导航 */
.site-nav { border-top: 1px solid var(--line); }

.nav-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
}

.nav-list > li { display: flex; }

.nav-list > li + li { border-left: 1px solid var(--line); }

.nav-list a {
  position: relative;
  display: flex;
  align-items: center;
  padding: 13px clamp(12px, 2.2vw, 28px);
  font-size: 15px;
  color: var(--ink-2);
  text-decoration: none;
  transition: color .18s var(--ease), background-color .18s var(--ease);
}

.nav-list a:hover { color: var(--ink); background: var(--signal-soft); }

.nav-list a[aria-current="page"] { color: var(--ink); font-weight: 700; }

.nav-list a[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: clamp(12px, 2.2vw, 28px);
  right: clamp(12px, 2.2vw, 28px);
  bottom: 6px;
  height: 3px;
  background: var(--signal);
}

/* 压缩态刊头 */
.site-header.is-condensed .masthead-kicker,
.site-header.is-condensed .masthead-line,
.site-header.is-condensed .index-rail { display: none; }

.site-header.is-condensed .masthead { padding-bottom: 6px; gap: 0; }
.site-header.is-condensed .masthead-brand { font-size: clamp(20px, 3vw, 28px); }
.site-header.is-condensed .header-inner { padding-block: 10px 0; }
.site-header.is-condensed .nav-list a { padding-block: 10px; }

/* 移动端断点 */
@media (max-width: 1079px) {
  .nav-toggle {
    display: flex;
    width: max-content;
    margin: 0 auto 12px;
  }

  .site-nav { display: none; }
  .site-nav[data-open] { display: block; }

  .nav-list { flex-direction: column; padding-block: 4px 10px; }

  .nav-list > li + li {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .nav-list a { padding: 15px 6px; font-size: 16px; }

  .nav-list a[aria-current="page"]::after {
    left: 6px;
    right: 6px;
    bottom: 9px;
  }
}

/* ---------- 14. 页脚 ---------- */
.site-footer {
  margin-top: clamp(56px, 9vw, 110px);
  background: var(--ink);
  color: #CBD6E3;
  border-top: 3px solid var(--signal);
  font-size: 14px;
  line-height: 1.7;
}

.footer-inner {
  width: min(100% - var(--gutter) * 2, var(--wrap));
  margin-inline: auto;
  padding-block: clamp(34px, 5vw, 60px) 0;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(26px, 4vw, 52px);
  padding-bottom: clamp(26px, 4vw, 44px);
  border-bottom: 1px solid rgba(217, 224, 228, .18);
}

@media (min-width: 720px) {
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1060px) {
  .footer-top { grid-template-columns: 1fr 2.1fr 1.1fr; }
}

.footer-kicker {
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: #7C8B9C;
}

.footer-mark {
  font-family: var(--font-display);
  font-weight: 800;
  font-stretch: condensed;
  font-size: clamp(26px, 3.4vw, 36px);
  line-height: 1;
  letter-spacing: -.02em;
  color: #FFFFFF;
}

.footer-mark span { color: var(--signal); }

.footer-note {
  margin-top: 10px;
  font-size: 13px;
  letter-spacing: .06em;
  color: #8FA0B3;
}

.footer-directory {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(140px, 100%), 1fr));
  gap: clamp(20px, 3vw, 32px);
}

.dir-title {
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--signal);
}

.footer-directory ul {
  display: grid;
  gap: 9px;
}

.footer-directory a {
  color: #CBD6E3;
  font-size: 14px;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  padding-bottom: 1px;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.footer-directory a:hover { color: #FFFFFF; border-color: var(--signal); }

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

.contact-list li { display: grid; gap: 2px; }

.contact-key {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: #7C8B9C;
}

.contact-value {
  color: #E4EBF3;
  font-size: 14px;
  font-variant-numeric: tabular-nums;
  word-break: break-word;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 22px;
  padding-block: clamp(20px, 3vw, 28px) clamp(24px, 3.6vw, 36px);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: #7C8B9C;
}

.footer-legal a {
  color: #9FB0C2;
  text-decoration: none;
  border-bottom: 1px solid rgba(159, 176, 194, .35);
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

.footer-legal a:hover { color: var(--signal); border-color: var(--signal); }

.footer-sign { color: #E4EBF3; letter-spacing: .1em; }
.footer-years { font-variant-numeric: tabular-nums; }
.footer-icp { margin-left: auto; }

/* ---------- 15. 入场显现 ---------- */
.js-reveal [data-reveal] {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity .24s var(--ease), transform .24s var(--ease);
}

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

/* ---------- 16. 减少动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

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

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