/* ============================================================
   极悦游艺 · 共享站点样式 /assets/site.css
   01 Reset · 02 Tokens · 03 中文排版 · 04 布局 · 05 工具类
   06 页头 · 07 页脚 · 08 组件 · 09 动效与无障碍
   ============================================================ */

/* ---------- 01 Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

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

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

address { font-style: normal; }

/* ---------- 02 Tokens ---------- */
:root {
  --indigo: #1B2A4A;
  --night: #101A2E;
  --gold: #D4A24C;
  --paper: #F5F1E8;
  --sand: #E8DFD0;
  --cyan: #2E8B8B;
  --red: #C0392B;
  --green: #3F7D4E;
  --yellow: #E0B23C;
  --grey: #6B7280;
  --white: #FFFFFF;

  --ink: #1B2A4A;
  --ink-soft: #4A5468;
  --line: rgba(27, 42, 74, 0.16);
  --line-soft: rgba(27, 42, 74, 0.08);

  --font-display: "Source Han Sans SC", "Source Han Sans CN", "Noto Sans SC",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui,
    -apple-system, "Segoe UI", sans-serif;
  --font-body: "Source Han Serif SC", "Source Han Serif CN", "Noto Serif SC",
    "Songti SC", STSong, "SimSun", Georgia, serif;
  --font-mono: ui-monospace, "SFMono-Regular", "Cascadia Mono", "Roboto Mono",
    Menlo, Consolas, "Liberation Mono", monospace;

  --max: 1280px;
  --gutter: clamp(20px, 4vw, 40px);

  --sp-1: 8px;
  --sp-2: 16px;
  --sp-3: 24px;
  --sp-4: 32px;
  --sp-5: 48px;
  --sp-6: 64px;
  --sp-7: 96px;

  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
  --header-h: 76px;
  --header-h-slim: 62px;
}

/* ---------- 03 中文排版基座 ---------- */
body {
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: clamp(15px, 1.05vw, 16.5px);
  line-height: 1.8;
  letter-spacing: 0.01em;
  color: var(--ink);
  background-color: var(--paper);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.24;
  letter-spacing: 0.02em;
  color: inherit;
  text-wrap: balance;
}

h1 { font-size: clamp(32px, 4.4vw, 56px); }
h2 { font-size: clamp(26px, 3vw, 40px); }
h3 { font-size: clamp(20px, 2.2vw, 28px); }
h4 { font-size: clamp(17px, 1.5vw, 20px); }

p { text-wrap: pretty; }

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

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}

/* ---------- 04 布局 ---------- */
.container {
  width: 100%;
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container--narrow { max-width: 900px; }

#main-content { scroll-margin-top: calc(var(--header-h) + 12px); }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--sp-3);
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 5fr) 1px minmax(0, 6fr);
  gap: clamp(24px, 3.4vw, 56px);
  align-items: start;
}

.split > * { min-width: 0; }

.split-rail {
  display: block;
  width: 1px;
  align-self: stretch;
  background-image: linear-gradient(
    180deg,
    var(--gold) 0%,
    rgba(27, 42, 74, 0.22) 46%,
    transparent 100%
  );
}

.theme-night {
  background-color: var(--indigo);
  color: rgba(255, 255, 255, 0.84);
}

.theme-night h1,
.theme-night h2,
.theme-night h3,
.theme-night h4 { color: var(--white); }

/* ---------- 05 工具类 ---------- */
.numeric {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
}

.prose p + p { margin-top: 1em; }
.prose ul, .prose ol {
  margin-top: 1em;
  padding-left: 1.4em;
}
.prose li + li { margin-top: 0.4em; }
.prose ul li { list-style: square; }
.prose ol li { list-style: decimal; }

.ribbon {
  height: 4px;
  width: 100%;
  background-image: linear-gradient(
    90deg,
    var(--cyan) 0 20%,
    var(--white) 20% 40%,
    var(--red) 40% 60%,
    var(--green) 60% 80%,
    var(--yellow) 80% 100%
  );
}

.slant {
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 48px), 0 100%);
}

/* ---------- 06 页头 ---------- */
.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 300;
  padding: 10px 18px;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--night);
  background: var(--gold);
  transform: translateY(-200%);
  transition: transform 0.18s var(--ease);
}

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

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  color: var(--white);
  background-color: transparent;
  background-image: linear-gradient(
    180deg,
    rgba(16, 26, 46, 0.66) 0%,
    rgba(16, 26, 46, 0.2) 58%,
    rgba(16, 26, 46, 0) 100%
  );
  transition: background-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.site-header[data-scrolled="true"] {
  background-image: none;
  background-color: var(--indigo);
  box-shadow:
    0 1px 0 rgba(212, 162, 76, 0.34),
    0 18px 40px -34px rgba(0, 0, 0, 0.9);
}

.header-inner {
  max-width: var(--max);
  margin-inline: auto;
  padding-inline: var(--gutter);
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  gap: clamp(12px, 2.4vw, 32px);
  transition: min-height 0.2s var(--ease);
}

.site-header[data-scrolled="true"] .header-inner {
  min-height: var(--header-h-slim);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.brand-glyph {
  display: inline-flex;
  align-items: flex-end;
  gap: 3px;
  height: 24px;
}

.brand-glyph-bar {
  display: block;
  width: 4px;
  transition: height 0.2s var(--ease);
}

.brand-glyph-bar:nth-child(1) { height: 12px; background: var(--cyan); }
.brand-glyph-bar:nth-child(2) { height: 24px; background: var(--gold); }
.brand-glyph-bar:nth-child(3) { height: 17px; background: var(--red); }

.brand-text { display: block; }

.brand-name {
  display: block;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  line-height: 1.1;
  letter-spacing: 0.16em;
  color: var(--white);
}

.brand-sub {
  display: block;
  font-family: var(--font-mono);
  font-size: 9px;
  line-height: 1.5;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.55);
}

/* 主导航 */
.site-nav {
  flex: 1 1 auto;
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: clamp(4px, 1.2vw, 20px);
  flex-wrap: nowrap;
}

.nav-item { flex: 0 0 auto; }

.nav-link {
  position: relative;
  display: inline-block;
  padding: 9px 2px;
  white-space: nowrap;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.76);
  transition: color 0.18s var(--ease);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 2px;
  height: 2px;
  background: rgba(255, 255, 255, 0.62);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.2s var(--ease), background-color 0.2s var(--ease);
}

.nav-link:hover { color: var(--white); }
.nav-link:hover::after { transform: scaleX(1); }

.nav-link[aria-current="page"] { color: var(--white); }
.nav-link[aria-current="page"]::after {
  background: var(--gold);
  transform: scaleX(1);
}

.nav-footnote { display: none; }

/* 右侧工具区 */
.header-tools {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.version-switch {
  display: inline-flex;
  align-items: stretch;
  border: 1px solid rgba(255, 255, 255, 0.26);
  background-color: rgba(16, 26, 46, 0.32);
}

.version-switch-label {
  display: inline-flex;
  align-items: center;
  padding: 0 9px;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.22em;
  color: rgba(255, 255, 255, 0.5);
  border-right: 1px solid rgba(255, 255, 255, 0.16);
}

.version-btn {
  padding: 7px 11px;
  white-space: nowrap;
  cursor: pointer;
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.72);
  transition: color 0.18s var(--ease), background-color 0.18s var(--ease),
    box-shadow 0.18s var(--ease);
}

.version-btn:hover {
  color: var(--white);
  background-color: rgba(255, 255, 255, 0.08);
}

.version-btn[aria-pressed="true"] {
  color: var(--gold);
  background-color: rgba(212, 162, 76, 0.1);
  box-shadow: inset 0 0 0 1px var(--gold);
}

.fav-entry {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 11px;
  white-space: nowrap;
  border: 1px solid rgba(255, 255, 255, 0.22);
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.78);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.fav-entry:hover {
  color: var(--white);
  border-color: rgba(212, 162, 76, 0.75);
}

.fav-entry-icon {
  display: block;
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  border: 1.5px solid currentColor;
  transform: rotate(45deg);
}

.fav-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 16px;
  height: 16px;
  padding: 0 4px;
  background: var(--gold);
  color: var(--night);
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0;
}

.fav-count[hidden] { display: none; }

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255, 255, 255, 0.26);
  cursor: pointer;
  transition: border-color 0.18s var(--ease);
}

.nav-toggle:hover { border-color: rgba(255, 255, 255, 0.62); }

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

.nav-toggle-box span {
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: var(--white);
  transition: transform 0.22s var(--ease), opacity 0.18s var(--ease);
}

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

.nav-toggle[aria-expanded="true"] .nav-toggle-box span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-box span:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-box span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

/* ---------- 07 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: var(--sp-7);
  background-color: var(--night);
  color: rgba(255, 255, 255, 0.78);
}

.site-footer::before {
  content: "";
  display: block;
  height: 4px;
  background-image: linear-gradient(
    90deg,
    var(--cyan) 0 20%,
    var(--white) 20% 40%,
    var(--red) 40% 60%,
    var(--green) 60% 80%,
    var(--yellow) 80% 100%
  );
}

.footer-inner {
  max-width: var(--max);
  margin-inline: auto;
  padding: clamp(48px, 6vw, 80px) var(--gutter) clamp(32px, 4vw, 56px);
  display: grid;
  grid-template-columns: minmax(220px, 1.5fr) 1fr 1fr minmax(250px, 1.4fr);
  gap: clamp(28px, 4vw, 56px);
}

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

.footer-brand-link {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0.16em;
  color: var(--white);
  border-bottom: 2px solid var(--gold);
  padding-bottom: 4px;
}

.footer-tagline {
  margin-top: 16px;
  max-width: 30em;
  font-size: 13.5px;
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.56);
}

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

.footer-col-title {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 16px;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--white);
}

.footer-col-title::before {
  content: "";
  display: block;
  flex: 0 0 auto;
  width: 3px;
  height: 13px;
  background: var(--cyan);
}

.footer-list li + li { margin-top: 10px; }

.footer-list a {
  display: inline-block;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.72);
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.footer-list a:hover {
  color: var(--white);
  border-bottom-color: var(--cyan);
}

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

.footer-address {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-contact-line {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 13.5px;
  line-height: 1.7;
}

.footer-contact-key {
  flex: 0 0 auto;
  padding: 1px 6px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: rgba(255, 255, 255, 0.5);
  border: 1px solid rgba(255, 255, 255, 0.18);
}

.footer-contact-value {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  color: rgba(255, 255, 255, 0.9);
  word-break: break-word;
}

.footer-contact-note {
  display: block;
  margin-top: 4px;
  padding-left: 12px;
  border-left: 2px solid rgba(212, 162, 76, 0.5);
  font-size: 12.5px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.5);
}

.footer-legal {
  max-width: var(--max);
  margin-inline: auto;
  padding: 20px var(--gutter) 36px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 24px;
}

.footer-copy {
  font-family: var(--font-display);
  font-size: 12px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: rgba(255, 255, 255, 0.52);
}

.footer-icp {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.42);
}

/* ---------- 08 组件 ---------- */
/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 22px;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-align: center;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background-color 0.18s var(--ease), color 0.18s var(--ease),
    border-color 0.18s var(--ease);
}

.btn--gold {
  background: var(--gold);
  border-color: var(--gold);
  color: var(--night);
}
.btn--gold:hover {
  background: #E2B466;
  border-color: #E2B466;
}

.btn--ghost {
  background: transparent;
  border-color: rgba(255, 255, 255, 0.42);
  color: var(--white);
}
.btn--ghost:hover {
  border-color: var(--white);
  background: rgba(255, 255, 255, 0.08);
}

.btn--ink {
  background: var(--indigo);
  border-color: var(--indigo);
  color: var(--white);
}
.btn--ink:hover {
  background: var(--night);
  border-color: var(--night);
}

.btn--quiet {
  background: transparent;
  border-color: var(--line);
  color: var(--indigo);
}
.btn--quiet:hover {
  border-color: var(--indigo);
  background: var(--sand);
}

/* 卡片 */
.card {
  background: var(--white);
  border: 1px solid var(--sand);
  padding: clamp(18px, 2vw, 26px);
}

.card--link {
  transition: transform 0.18s var(--ease), border-color 0.18s var(--ease);
}

.card--link:hover,
.card--link:focus-visible {
  transform: translateY(-2px);
  border-color: var(--indigo);
}

/* 分类标签 */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 700;
  line-height: 1.75;
  letter-spacing: 0.12em;
  border: 1px solid transparent;
}

.tag--cyan {
  background: rgba(46, 139, 139, 0.14);
  border-color: rgba(46, 139, 139, 0.46);
  color: #1F6E6E;
}
.tag--red {
  background: rgba(192, 57, 43, 0.12);
  border-color: rgba(192, 57, 43, 0.44);
  color: #9E2F22;
}
.tag--green {
  background: rgba(63, 125, 78, 0.13);
  border-color: rgba(63, 125, 78, 0.46);
  color: #2F6240;
}
.tag--yellow {
  background: rgba(224, 178, 60, 0.22);
  border-color: rgba(224, 178, 60, 0.6);
  color: #7A5B10;
}
.tag--muted {
  background: var(--sand);
  border-color: var(--line);
  color: var(--ink-soft);
}

.theme-night .tag--cyan {
  background: rgba(46, 139, 139, 0.28);
  border-color: rgba(46, 139, 139, 0.62);
  color: #96DADA;
}
.theme-night .tag--red {
  background: rgba(192, 57, 43, 0.26);
  border-color: rgba(192, 57, 43, 0.62);
  color: #F0A79C;
}
.theme-night .tag--green {
  background: rgba(63, 125, 78, 0.28);
  border-color: rgba(63, 125, 78, 0.62);
  color: #9FD2AF;
}
.theme-night .tag--yellow {
  background: rgba(224, 178, 60, 0.26);
  border-color: rgba(224, 178, 60, 0.64);
  color: #F0D28A;
}
.theme-night .tag--muted {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.22);
  color: rgba(255, 255, 255, 0.72);
}

/* 面包屑 */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--grey);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
}

.breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--sand);
}

.breadcrumb a {
  color: inherit;
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.breadcrumb a:hover {
  color: var(--indigo);
  border-bottom-color: var(--gold);
}

.theme-night .breadcrumb { color: rgba(255, 255, 255, 0.58); }
.theme-night .breadcrumb a:hover { color: var(--white); }
.theme-night .breadcrumb li + li::before { color: rgba(255, 255, 255, 0.3); }

/* 展览标签式小标题 */
.section-label {
  --label-tone: var(--cyan);
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 5px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--indigo);
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(27, 42, 74, 0.28);
}

.section-label::before {
  content: "";
  display: block;
  flex: 0 0 auto;
  width: 8px;
  height: 8px;
  background: var(--label-tone);
}

.theme-night .section-label {
  color: rgba(255, 255, 255, 0.86);
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.26);
}

/* 图片容器 */
.figure {
  position: relative;
  display: block;
  margin: 0;
  overflow: hidden;
  background-color: var(--sand);
}

.figure--43 { aspect-ratio: 4 / 3; }
.figure--169 { aspect-ratio: 16 / 9; }
.figure--11 { aspect-ratio: 1 / 1; }
.figure--219 { aspect-ratio: 21 / 9; }

.figure > img,
.figure > svg,
.figure > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure--placeholder {
  background-color: var(--indigo);
  background-image:
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.07) 0 1px, transparent 1px 26px),
    repeating-linear-gradient(0deg, rgba(255, 255, 255, 0.07) 0 1px, transparent 1px 26px),
    linear-gradient(155deg, rgba(46, 139, 139, 0.42) 0%, rgba(27, 42, 74, 0.16) 52%, rgba(16, 26, 46, 0.94) 100%);
}

.figure-caption {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 2px solid var(--sand);
  font-family: var(--font-body);
  font-size: 13px;
  line-height: 1.7;
  color: var(--grey);
}

.theme-night .figure-caption {
  border-left-color: rgba(255, 255, 255, 0.24);
  color: rgba(255, 255, 255, 0.56);
}

/* 可展开内容组 */
.accordion { border-top: 1px solid var(--line); }

.accordion-item { border-bottom: 1px solid var(--line); }

.accordion-trigger {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  width: 100%;
  padding: 16px 0;
  text-align: left;
  cursor: pointer;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.6;
  color: var(--ink);
  transition: color 0.18s var(--ease);
}

.accordion-trigger:hover { color: var(--cyan); }

.accordion-index {
  flex: 0 0 auto;
  padding-top: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--grey);
  transition: color 0.2s var(--ease);
}

.accordion-item[data-open="true"] .accordion-index { color: var(--cyan); }

.accordion-trigger > span:nth-child(2) { min-width: 0; }

.accordion-sign {
  position: relative;
  flex: 0 0 auto;
  margin-left: auto;
  margin-top: 2px;
  width: 20px;
  height: 20px;
  border: 1px solid currentColor;
}

.accordion-sign::before,
.accordion-sign::after {
  content: "";
  position: absolute;
  background: currentColor;
  transition: transform 0.24s ease-out, opacity 0.24s ease-out;
}

.accordion-sign::before {
  top: 8.5px;
  left: 4px;
  right: 4px;
  height: 1px;
}

.accordion-sign::after {
  left: 8.5px;
  top: 4px;
  bottom: 4px;
  width: 1px;
}

.accordion-trigger[aria-expanded="true"] .accordion-sign::after {
  transform: scaleY(0);
  opacity: 0;
}

.accordion-panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.24s ease-out;
}

.accordion-item[data-open="true"] .accordion-panel {
  grid-template-rows: 1fr;
}

.accordion-panel-inner { overflow: hidden; }

.accordion-body {
  padding: 0 0 18px 34px;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.theme-night .accordion { border-top-color: rgba(255, 255, 255, 0.16); }
.theme-night .accordion-item { border-bottom-color: rgba(255, 255, 255, 0.16); }
.theme-night .accordion-trigger { color: var(--white); }
.theme-night .accordion-trigger:hover { color: var(--gold); }
.theme-night .accordion-index { color: rgba(255, 255, 255, 0.5); }
.theme-night .accordion-body { color: rgba(255, 255, 255, 0.66); }

/* ---------- 09 动效与无障碍 ---------- */
[data-reveal] { opacity: 1; transform: none; }

.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
}

.js-ready [data-reveal][data-revealed="true"] {
  opacity: 1;
  transform: none;
}

/* ---------- 10 响应式 ---------- */
@media (max-width: 1080px) {
  .nav-link { font-size: 13px; letter-spacing: 0.04em; }
  .version-switch-label { display: none; }
}

@media (max-width: 1000px) {
  .footer-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 1;
    width: min(88vw, 370px);
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    padding: 92px 26px 40px;
    background-color: var(--night);
    background-image: linear-gradient(
      165deg,
      rgba(46, 139, 139, 0.22) 0%,
      rgba(16, 26, 46, 0) 46%
    );
    border-left: 1px solid rgba(212, 162, 76, 0.34);
    box-shadow: -30px 0 70px -40px rgba(0, 0, 0, 0.95);
    transform: translateX(101%);
    visibility: hidden;
    overflow-y: auto;
    overscroll-behavior: contain;
    transition: transform 0.26s var(--ease), visibility 0.26s var(--ease);
  }

  .site-nav[data-open="true"] {
    transform: translateX(0);
    visibility: visible;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-item { border-bottom: 1px solid rgba(255, 255, 255, 0.1); }

  .nav-link {
    display: block;
    padding: 15px 0;
    font-size: 16px;
    letter-spacing: 0.08em;
    color: rgba(255, 255, 255, 0.82);
  }

  .nav-link::after { display: none; }
  .nav-link:hover { color: var(--white); }

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

  .nav-link[aria-current="page"]::before {
    content: "";
    display: inline-block;
    width: 7px;
    height: 7px;
    margin-right: 10px;
    vertical-align: 2px;
    background: var(--gold);
  }

  .nav-footnote {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-top: auto;
    padding-top: 28px;
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.18em;
    color: rgba(255, 255, 255, 0.42);
  }

  .nav-footnote-rule {
    display: block;
    flex: 0 0 auto;
    width: 26px;
    height: 1px;
    background: var(--gold);
  }

  .header-inner { min-height: 64px; }
  .site-header[data-scrolled="true"] .header-inner { min-height: 56px; }

  .split {
    grid-template-columns: minmax(0, 1fr);
  }
  .split-rail { display: none; }

  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }

  html.nav-open,
  html.nav-open body { overflow: hidden; }
}

@media (max-width: 620px) {
  .footer-inner { grid-template-columns: minmax(0, 1fr); gap: 34px; }
  .footer-legal { flex-direction: column; align-items: flex-start; }

  .version-btn { padding: 7px 8px; font-size: 11px; letter-spacing: 0.04em; }
  .fav-entry-text { display: none; }
  .fav-entry { padding: 7px 8px; gap: 0; }
  .brand-sub { display: none; }
  .brand-name { font-size: 17px; letter-spacing: 0.12em; }
  .brand-glyph { height: 20px; }
  .brand-glyph-bar:nth-child(1) { height: 10px; }
  .brand-glyph-bar:nth-child(2) { height: 20px; }
  .brand-glyph-bar:nth-child(3) { height: 14px; }

  .grid-12 { grid-template-columns: minmax(0, 1fr); }

  .site-footer { margin-top: var(--sp-6); }
}

@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;
  }

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

  .card--link:hover { transform: none; }
}