/* ============================================================
   爱游戏赛场 · /assets/site.css
   共享骨架：重置 / 变量 / 中文排版 / 头部 / 页脚 / 基础组件
   ============================================================ */

/* ---------- 1. 重置 ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 112px;
}

body {
  margin: 0;
  min-height: 100vh;
  background-color: #0A1A2F;
  color: #F2F5F8;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a { color: var(--electric); text-decoration: none; }

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

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

::selection { background: var(--electric); color: #06202B; }

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

/* ---------- 2. 变量 ---------- */
:root {
  /* 色彩 */
  --deep: #0A1A2F;
  --night: #0F2440;
  --slate: #16324F;
  --electric: #23E0D0;
  --amber: #FF9A2E;
  --signal: #FF4D5E;
  --neon: #7CF77A;
  --paper: #F2F5F8;
  --ink: #8FA3B8;
  --soft: #C6D5E4;

  --line: rgba(143, 163, 184, .24);
  --line-strong: rgba(35, 224, 208, .38);

  /* 字体 */
  --font-display: "Arial Narrow", "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", system-ui, -apple-system, sans-serif;
  --font-num: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Courier New", monospace;

  /* 四级字号阶梯 */
  --size-xl: clamp(2.6rem, 7vw, 5rem);
  --size-lg: clamp(1.8rem, 3.6vw, 2.4rem);
  --size-md: 1.15rem;
  --size-xs: .75rem;

  /* 布局 */
  --shell: 1240px;
  --rail: 88px;
  --header-h: 78px;
  --gap-block: clamp(72px, 9vw, 120px);

  /* 动效 */
  --ease: cubic-bezier(.2, .8, .2, 1);
  --dur: 220ms;
}

/* ---------- 3. 中文排版 ---------- */
h1, h2, h3, h4 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: .98;
  text-wrap: balance;
}

h1 { font-size: var(--size-xl); }
h2 { font-size: var(--size-lg); }
h3 {
  font-size: var(--size-md);
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: 0;
}

p {
  margin: 0 0 18px;
  max-width: 68ch;
  overflow-wrap: break-word;
}

p:last-child { margin-bottom: 0; }

strong { color: var(--paper); font-weight: 700; }

.label {
  display: inline-block;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--ink);
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 4. 骨架容器 ---------- */
.shell {
  width: min(var(--shell), 100% - 40px);
  margin-inline: auto;
}

#main-content {
  display: block;
  padding-top: clamp(104px, 13vh, 148px);
}

/* ---------- 5. 左侧品牌轨道 ---------- */
.site-rail { display: none; }

body.has-rail .site-rail {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: 70;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  width: var(--rail);
  padding: 96px 0 30px;
  background: var(--night);
  border-right: 1px solid var(--line);
  pointer-events: none;
}

.rail-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  height: 100%;
  gap: 22px;
}

.rail-brand {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 800;
  letter-spacing: .34em;
  color: var(--paper);
}

.rail-rule {
  flex: 1 1 auto;
  width: 1px;
  background: linear-gradient(180deg, var(--electric), rgba(35, 224, 208, 0));
}

.rail-num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  letter-spacing: .1em;
  color: var(--amber);
}

.rail-tick {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--neon);
  box-shadow: 0 0 0 4px rgba(124, 247, 122, .14);
}

@media (min-width: 1120px) {
  body.has-rail { padding-left: var(--rail); }
  body.has-rail .site-header { padding-left: var(--rail); }
}

/* ---------- 6. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: -72px;
  left: 16px;
  z-index: 200;
  padding: 11px 20px;
  background: var(--electric);
  color: #06202B;
  font-size: 14px;
  font-weight: 700;
  border-radius: 999px;
  transition: top var(--dur) var(--ease);
}

.skip-link:focus { top: 14px; }

/* ---------- 7. 头部 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 90;
  padding: 14px 0 0;
  transition: padding var(--dur) var(--ease);
}

.site-header[data-stuck="true"] { padding-top: 8px; }

.header-inner {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  width: min(var(--shell), 100% - 40px);
  margin-inline: auto;
  padding: 9px 14px 15px 16px;
  background: rgba(15, 36, 64, .78);
  border: 1px solid rgba(35, 224, 208, .2);
  border-radius: 999px;
  box-shadow: 0 22px 44px -30px rgba(0, 0, 0, .95);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  transition: background var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              padding var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.site-header[data-stuck="true"] .header-inner {
  padding-top: 6px;
  padding-bottom: 12px;
  background: rgba(10, 26, 47, .95);
  border-color: rgba(35, 224, 208, .34);
  box-shadow: 0 26px 52px -30px rgba(0, 0, 0, 1);
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  color: var(--paper);
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--electric), #1a9ec4);
  color: #06202B;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 800;
  transition: transform var(--dur) var(--ease);
}

.brand:hover .brand-mark { transform: rotate(-6deg); }

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

.brand-name {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .02em;
  color: var(--paper);
}

.brand-note {
  font-family: var(--font-num);
  font-size: 10px;
  letter-spacing: .14em;
  color: var(--ink);
  transition: color var(--dur) var(--ease);
}

.brand:hover .brand-note { color: var(--electric); }

/* 章节读数 */
.header-readout {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
  max-width: 0;
  padding-left: 0;
  margin-left: 0;
  overflow: hidden;
  white-space: nowrap;
  opacity: 0;
  border-left: 1px solid var(--line);
  transition: max-width var(--dur) var(--ease),
              opacity var(--dur) var(--ease),
              padding-left var(--dur) var(--ease);
}

.site-header[data-stuck="true"] .header-readout {
  max-width: 240px;
  padding-left: 14px;
  margin-left: 6px;
  opacity: 1;
}

.readout-num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  color: var(--amber);
}

.readout-name {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--electric);
}

/* 导航 */
.primary-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

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

.nav-link {
  position: relative;
  display: block;
  padding: 8px 13px;
  border-radius: 999px;
  font-size: 14px;
  color: var(--soft);
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 3px;
  width: 0;
  height: 1px;
  background: currentColor;
  transform: translateX(-50%);
  transition: width var(--dur) var(--ease);
}

.nav-link:hover { color: var(--paper); background: rgba(35, 224, 208, .09); }
.nav-link:hover::after { width: 42%; }

.nav-link[aria-current="page"] {
  background: var(--electric);
  color: #06202B;
  font-weight: 600;
}

.nav-link[aria-current="page"]::after { display: none; }

.nav-utility {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-left: 8px;
  padding-left: 12px;
  border-left: 1px solid var(--line);
}

.header-util {
  display: block;
  padding: 6px 9px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--ink);
  border-radius: 999px;
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.header-util:hover { color: var(--electric); background: rgba(35, 224, 208, .09); }

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: 10px;
}

/* 移动端按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 8px 14px 8px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--paper);
  font-size: 12px;
  letter-spacing: .12em;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.nav-toggle:hover { border-color: var(--line-strong); background: rgba(35, 224, 208, .08); }

.nav-toggle-box {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 16px;
}

.nav-toggle-box span {
  display: block;
  width: 16px;
  height: 1.5px;
  border-radius: 2px;
  background: var(--electric);
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.nav-toggle-box span:nth-child(2) { width: 11px; }

.site-header[data-open="true"] .nav-toggle-box span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.site-header[data-open="true"] .nav-toggle-box span:nth-child(2) { opacity: 0; }
.site-header[data-open="true"] .nav-toggle-box span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* 阅读进度 */
.header-progress {
  position: absolute;
  left: 26px;
  right: 26px;
  bottom: 6px;
  height: 2px;
  border-radius: 2px;
  overflow: hidden;
  background: rgba(143, 163, 184, .14);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur) var(--ease);
}

.site-header[data-stuck="true"] .header-progress { opacity: 1; }

.header-progress-bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--electric), var(--amber));
  transition: transform 120ms linear;
}

@media (max-width: 1024px) {
  .header-inner { padding: 9px 12px 9px 14px; }

  .header-readout { display: none; }

  .nav-toggle { display: inline-flex; }

  .header-actions { margin-left: auto; }

  .primary-nav {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    display: block;
    margin: 0;
    padding: 12px;
    background: rgba(10, 26, 47, .98);
    border: 1px solid rgba(35, 224, 208, .28);
    border-radius: 24px;
    box-shadow: 0 34px 64px -34px rgba(0, 0, 0, 1);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    pointer-events: none;
    transition: opacity var(--dur) var(--ease),
                transform var(--dur) var(--ease),
                visibility var(--dur) var(--ease);
  }

  .site-header[data-open="true"] .primary-nav {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
  }

  .nav-list { flex-direction: column; align-items: stretch; gap: 2px; }

  .nav-link { padding: 13px 16px; border-radius: 14px; font-size: 15px; }

  .nav-link::after { display: none; }

  .nav-utility {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    margin: 10px 0 0;
    padding: 10px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .header-util { padding: 11px 16px; font-size: 12px; border-radius: 14px; }
}

@media (max-width: 640px) {
  .header-inner { width: calc(100% - 24px); }
  .brand-note { display: none; }
  .header-cta { display: none; }
  .nav-toggle-text { display: none; }
}

/* ---------- 8. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: var(--gap-block);
  padding: clamp(56px, 7vw, 88px) 0 30px;
  background: linear-gradient(180deg, var(--night) 0%, var(--deep) 62%);
  border-top: 1px solid var(--line-strong);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 180px;
  height: 2px;
  background: linear-gradient(90deg, var(--electric), rgba(35, 224, 208, 0));
}

.site-footer::after {
  content: "爱游戏赛场";
  position: absolute;
  right: -12px;
  bottom: -32px;
  font-family: var(--font-display);
  font-size: clamp(4rem, 14vw, 12rem);
  font-weight: 800;
  letter-spacing: -.04em;
  line-height: 1;
  white-space: nowrap;
  color: rgba(143, 163, 184, .05);
  pointer-events: none;
  user-select: none;
}

.footer-top {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.6fr);
  gap: clamp(32px, 5vw, 64px);
}

.footer-brand {
  display: grid;
  align-content: start;
  gap: 14px;
}

.footer-mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--electric), #1a9ec4);
  color: #06202B;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
}

.footer-slogan {
  margin: 0;
  max-width: 22ch;
  font-family: var(--font-display);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  font-weight: 700;
  line-height: 1.35;
  letter-spacing: -.01em;
  color: var(--paper);
}

.footer-note {
  margin: 0;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ink);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
}

.footer-col-title {
  margin-bottom: 16px;
  font-family: var(--font-num);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--electric);
}

.footer-links { display: grid; gap: 10px; }

.footer-links a {
  position: relative;
  display: inline-block;
  font-size: 14px;
  color: var(--soft);
  transition: color var(--dur) var(--ease);
}

.footer-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 1px;
  background: var(--electric);
  transition: width var(--dur) var(--ease);
}

.footer-links a:hover { color: var(--electric); }
.footer-links a:hover::after { width: 100%; }

.footer-contact {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 12px;
  margin-top: clamp(36px, 5vw, 54px);
  padding-top: 32px;
  border-top: 1px solid var(--line);
}

.footer-meta {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 28px;
  margin-top: 8px;
}

.footer-hours,
.footer-address {
  margin: 0;
  font-size: 12.5px;
  letter-spacing: .02em;
  color: var(--ink);
}

.footer-hours::before { content: "◇ "; color: var(--neon); }
.footer-address::before { content: "◇ "; color: var(--amber); }

.footer-bottom {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px;
  margin-top: 40px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.footer-copy,
.footer-legal {
  margin: 0;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--ink);
}

.footer-legal { color: var(--amber); }

@media (max-width: 860px) {
  .footer-top { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  .footer-cols { grid-template-columns: 1fr 1fr; gap: 24px 20px; }
  .footer-bottom { flex-direction: column; }
}

/* ---------- 9. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 24px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .04em;
  white-space: nowrap;
  transition: background var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              transform var(--dur) var(--ease);
}

.btn-primary {
  background: var(--amber);
  color: #24160A;
}

.btn-primary:hover {
  background: #FFB35C;
  transform: translateY(-1px);
}

.btn-ghost {
  background: rgba(35, 224, 208, .06);
  border-color: rgba(35, 224, 208, .45);
  color: var(--electric);
}

.btn-ghost:hover {
  background: rgba(35, 224, 208, .16);
  border-color: var(--electric);
}

.btn-sm {
  padding: 8px 16px;
  font-size: 12px;
  letter-spacing: .08em;
}

/* ---------- 10. 面包屑 ---------- */
.breadcrumb {
  margin-bottom: 26px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--ink);
}

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

.breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb li + li::before {
  content: "/";
  color: rgba(143, 163, 184, .45);
}

.breadcrumb a {
  color: var(--ink);
  transition: color var(--dur) var(--ease);
}

.breadcrumb a:hover { color: var(--electric); }

/* ---------- 11. 章节起手式 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--electric);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 2px;
  background: var(--electric);
}

.section-title { margin-bottom: 20px; }

.lede {
  max-width: 62ch;
  font-size: 1.15rem;
  line-height: 1.8;
  color: var(--soft);
}

.prose p { color: var(--soft); }

.prose h2 {
  margin-top: 56px;
  margin-bottom: 18px;
}

.prose h3 {
  margin-top: 34px;
  margin-bottom: 12px;
  color: var(--paper);
}

.prose ul { margin-bottom: 22px; }

.prose li {
  position: relative;
  margin-bottom: 10px;
  padding-left: 20px;
  color: var(--soft);
}

.prose li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 8px;
  height: 2px;
  background: var(--amber);
}

/* ---------- 12. 卡片 ---------- */
.card {
  position: relative;
  padding: 26px 26px 28px;
  background: linear-gradient(160deg, rgba(22, 50, 79, .92), rgba(15, 36, 64, .78));
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
  transition: border-color var(--dur) var(--ease),
              transform var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 3px;
  background: var(--electric);
  transform: scaleY(0);
  transform-origin: top center;
  transition: transform var(--dur) var(--ease);
}

.card:hover {
  border-color: var(--line-strong);
  box-shadow: 0 26px 48px -34px rgba(0, 0, 0, 1);
}

.card:hover::before { transform: scaleY(1); }

.card-body {
  position: relative;
  transition: transform var(--dur) var(--ease);
}

.card:hover .card-body { transform: translateX(6px); }

.card-tilt-left { transform: rotate(-1.4deg); }
.card-tilt-right { transform: rotate(1.1deg); }

.card-tilt-left:hover { transform: rotate(0deg) translateY(-2px); }
.card-tilt-right:hover { transform: rotate(0deg) translateY(-2px); }

.card-stack { position: relative; }

.card-stack::after {
  content: "";
  position: absolute;
  inset: 12px -12px -12px 12px;
  border: 1px solid var(--line);
  z-index: -1;
  pointer-events: none;
}

/* ---------- 13. 分栏 ---------- */
.split {
  display: grid;
  gap: clamp(28px, 4vw, 48px);
}

.split-8-4 { grid-template-columns: minmax(0, 8fr) minmax(0, 4fr); }
.split-7-5 { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }

.offset-down { margin-top: clamp(24px, 5vw, 56px); }
.offset-up { margin-top: clamp(-48px, -3vw, -20px); }

@media (max-width: 900px) {
  .split-8-4,
  .split-7-5 { grid-template-columns: minmax(0, 1fr); }
  .offset-up { margin-top: 0; }
}

/* ---------- 14. 图片容器 ---------- */
.img-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 3px;
  background: linear-gradient(135deg, rgba(35, 224, 208, .14), rgba(15, 36, 64, .92) 55%, rgba(255, 154, 46, .12));
  aspect-ratio: 16 / 10;
}

.img-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.92) contrast(1.06);
  transition: transform 420ms var(--ease), filter 420ms var(--ease);
}

.img-frame:hover img {
  transform: scale(1.03);
  filter: saturate(1.06) contrast(1.1);
}

.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(0deg, rgba(10, 26, 47, .26) 0 1px, rgba(10, 26, 47, 0) 1px 3px);
  pointer-events: none;
}

.img-frame--wide { aspect-ratio: 21 / 9; }
.img-frame--tall { aspect-ratio: 4 / 5; }
.img-frame--square { aspect-ratio: 1 / 1; }

.img-cap {
  display: block;
  margin-top: 10px;
  font-family: var(--font-num);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--ink);
}

/* ---------- 15. 时间轴 ---------- */
.timeline {
  position: relative;
  padding-left: 28px;
}

.timeline::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--amber), rgba(255, 154, 46, .05));
}

.timeline-item {
  position: relative;
  padding-bottom: 34px;
}

.timeline-item:last-child { padding-bottom: 0; }

.timeline-item::before {
  content: "";
  position: absolute;
  top: 8px;
  left: -26px;
  width: 9px;
  height: 9px;
  background: var(--amber);
  transform: rotate(45deg);
}

/* ---------- 16. 纵向清单 ---------- */
.ledger { border-top: 1px solid var(--line); }

.ledger-item {
  display: grid;
  grid-template-columns: 82px minmax(0, 1fr) auto;
  gap: 20px;
  align-items: baseline;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.ledger-item:hover {
  background: rgba(35, 224, 208, .045);
  border-bottom-color: rgba(35, 224, 208, .4);
}

@media (max-width: 640px) {
  .ledger-item { grid-template-columns: 62px minmax(0, 1fr); }
}

/* ---------- 17. 数字与统计 ---------- */
.num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
  color: var(--amber);
}

.num-lg {
  display: inline-block;
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(2.2rem, 5vw, 4rem);
  font-weight: 700;
  line-height: .9;
  color: var(--amber);
}

.stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.stat-num {
  font-family: var(--font-num);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1;
  color: var(--electric);
}

.stat-label {
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ink);
}

/* ---------- 18. 标签与状态点 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 5px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--ink);
}

.tag--live { color: var(--neon); border-color: rgba(124, 247, 122, .42); }
.tag--amber { color: var(--amber); border-color: rgba(255, 154, 46, .42); }
.tag--alert { color: var(--signal); border-color: rgba(255, 77, 94, .42); }

.status-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--neon);
  box-shadow: 0 0 0 3px rgba(124, 247, 122, .16);
}

/* ---------- 19. 问答手风琴 ---------- */
.faq { border-top: 1px solid var(--line); }

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

.faq-item summary {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 22px 0;
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--paper);
  cursor: pointer;
  list-style: none;
  transition: color var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-num);
  font-size: 18px;
  line-height: 1;
  color: var(--electric);
  transition: transform var(--dur) var(--ease);
}

.faq-item summary:hover { color: var(--electric); }

.faq-item[open] summary {
  padding-left: 18px;
  color: var(--electric);
}

.faq-item[open] summary::after { transform: rotate(45deg); }

.faq-item[open] summary::before {
  content: "";
  position: absolute;
  top: 18px;
  bottom: 18px;
  left: 0;
  width: 2px;
  background: var(--electric);
}

.faq-body {
  padding: 0 0 24px 18px;
  color: var(--soft);
}

/* ---------- 20. 纯 CSS 筛选 ---------- */
.filter-set { display: block; }

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
}

.filter-chip {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 13px;
  color: var(--ink);
  cursor: pointer;
  transition: background var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.filter-chip input {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: 0;
  opacity: 0;
  pointer-events: none;
}

.filter-chip:hover {
  border-color: rgba(35, 224, 208, .5);
  color: var(--paper);
}

.filter-chip:has(input:checked) {
  background: var(--electric);
  border-color: var(--electric);
  color: #06202B;
  font-weight: 600;
}

.filter-chip:has(input:focus-visible) {
  outline: 2px solid var(--electric);
  outline-offset: 3px;
}

.filter-set:has(input[data-filter="live"]:checked) .filter-item:not([data-cat~="live"]) { display: none; }
.filter-set:has(input[data-filter="archive"]:checked) .filter-item:not([data-cat~="archive"]) { display: none; }
.filter-set:has(input[data-filter="guide"]:checked) .filter-item:not([data-cat~="guide"]) { display: none; }

/* ---------- 21. 复制区 ---------- */
.copy-field {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 10px 10px 10px 16px;
  background: rgba(15, 36, 64, .68);
  border: 1px dashed var(--line);
  border-radius: 3px;
  transition: border-color var(--dur) var(--ease);
}

.copy-field:hover { border-color: var(--line-strong); }

.copy-key {
  flex: 0 0 auto;
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--ink);
}

.copy-value {
  flex: 1 1 auto;
  min-width: 0;
  font-family: var(--font-num);
  font-size: 13px;
  color: var(--paper);
  overflow-wrap: anywhere;
}

.copy-btn {
  flex: 0 0 auto;
  padding: 6px 14px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--electric);
  font-size: 12px;
  letter-spacing: .08em;
  transition: background var(--dur) var(--ease),
              color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.copy-btn:hover { background: rgba(35, 224, 208, .14); }

.copy-btn[data-copied="true"] {
  background: var(--neon);
  border-color: var(--neon);
  color: #0A1A2F;
}

/* ---------- 22. 视口显现 ---------- */
.reveal { opacity: 1; }

.js .reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 420ms var(--ease), transform 420ms var(--ease);
}

.js .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 23. 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }

  .js .reveal { opacity: 1; transform: none; }
}