/* ==========================================================================
   KK赛场 · 共享站点样式 (assets/site.css)
   深夜蓝底 × 场地绿骨 × 信号橙刻度 × 米白纸叠
   ========================================================================== */

/* ---------- 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, dl, dt, dd, address { margin: 0; padding: 0; }
ul, ol { list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
address { font-style: normal; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  --night: #0B1B2B;
  --grass: #186B4A;
  --moss: #3E7A5C;
  --signal: #FF6B2C;
  --signal-soft: #FF8A55;
  --clay: #B2552F;
  --slate: #3A4149;
  --graphite: #14181C;
  --paper: #F5F1E8;
  --white: #FFFFFF;
  --teal: #4F8FA8;
  --mist: #C9CFD4;

  --line: rgba(58, 65, 73, .22);
  --line-strong: rgba(58, 65, 73, .45);
  --line-light: rgba(245, 241, 232, .16);
  --on-dark: rgba(245, 241, 232, .72);

  --font-sans: "思源黑体", "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", "SF Mono", Consolas, "Liberation Mono", monospace;
  --font-narrow: "Archivo Narrow", "Arial Narrow", var(--font-sans);

  --fs-display: clamp(30px, 5.2vw, 56px);
  --fs-h2: clamp(22px, 3vw, 34px);
  --fs-h3: clamp(18px, 2.2vw, 22px);
  --fs-body: 17px;

  --shell: 1200px;
  --gutter: clamp(16px, 4vw, 40px);
  --radius-card: 4px;
  --radius-pill: 999px;

  --dur: .45s;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 基础排版 ---------- */
html { background: var(--paper); }
body {
  background: var(--paper);
  color: var(--slate);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.75;
  letter-spacing: .01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, h4 { color: var(--graphite); line-height: 1.18; letter-spacing: -.012em; font-weight: 700; }
h1 { font-size: var(--fs-display); }
h2 { font-size: var(--fs-h2); }
h3 { font-size: var(--fs-h3); }
strong { font-weight: 700; color: var(--graphite); }
.num { font-family: var(--font-mono); font-variant-numeric: tabular-nums; letter-spacing: -.01em; }

.prose { max-width: 70ch; }
.prose p { margin-bottom: 1.2em; }
.prose p:last-child { margin-bottom: 0; }
.prose ul, .prose ol { margin: 0 0 1.2em 1.25em; list-style: disc; }
.prose ol { list-style: decimal; }
.prose li { margin-bottom: .45em; }
.prose a { color: var(--clay); border-bottom: 1px solid rgba(178, 85, 47, .42); }
.prose a:hover { color: var(--signal); border-color: var(--signal); }

/* ---------- 4. 布局容器 ---------- */
.container {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.container--narrow { max-width: 760px; }
.section { padding: clamp(48px, 7vw, 96px) 0; }
.section--tight { padding: clamp(30px, 4vw, 52px) 0; }
#main-content { display: block; min-height: 40vh; outline: none; }

.grid-12 { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: clamp(14px, 2vw, 24px); }
.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-12 { grid-column: span 12; }

.eyebrow {
  display: inline-block;
  font-family: var(--font-narrow);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--grass);
}

/* ---------- 5. 通用按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 24px;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .06em;
  transition: background .22s var(--ease), color .22s var(--ease), border-color .22s var(--ease), transform .22s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn--solid { background: var(--grass); color: var(--paper); }
.btn--solid:hover { background: #1C7D57; }
.btn--orange { background: var(--signal); color: #fff; }
.btn--orange:hover { background: #FF7D45; }
.btn--ghost { border-color: var(--line-strong); color: var(--graphite); }
.btn--ghost:hover { border-color: var(--signal); color: var(--clay); }
.btn--onDark { border-color: rgba(245, 241, 232, .3); color: var(--paper); }
.btn--onDark:hover { border-color: var(--signal); color: var(--signal-soft); }

/* ---------- 6. 面包屑 / 刻度线 / 水印 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 20px 0 4px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--slate);
  opacity: .8;
}
.breadcrumb__item { display: inline-flex; align-items: center; gap: 8px; }
.breadcrumb__item a:hover { color: var(--signal); text-decoration: underline; text-underline-offset: 4px; }
.breadcrumb__sep { color: var(--mist); }

.tick-rule {
  height: 14px;
  border-bottom: 1px solid var(--line);
  background-image: repeating-linear-gradient(90deg, rgba(58, 65, 73, .35) 0 1px, transparent 1px 14px);
  background-size: 100% 8px;
  background-repeat: repeat-x;
  background-position: left bottom;
}

.watermark-num {
  position: absolute;
  right: -.06em;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(90px, 16vw, 190px);
  line-height: .8;
  color: rgba(58, 65, 73, .07);
  pointer-events: none;
  user-select: none;
}
.watermark-num--onDark { color: rgba(245, 241, 232, .08); }

/* ---------- 7. 章节色带 ---------- */
.chapter-band {
  position: relative;
  overflow: hidden;
  padding: 20px var(--gutter);
  background: var(--night);
  color: var(--paper);
  border-top: 1px solid var(--line-light);
  border-bottom: 1px solid var(--line-light);
}
.chapter-band--paper { background: var(--paper); color: var(--graphite); border-color: var(--line); }
.chapter-band--grass { background: var(--grass); border-color: rgba(245, 241, 232, .22); }
.chapter-band__inner {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: clamp(12px, 2.4vw, 28px);
}
.chapter-band__num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 4vw, 44px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: rgba(245, 241, 232, .26);
}
.chapter-band--paper .chapter-band__num { color: rgba(58, 65, 73, .2); }
.chapter-band__title { font-size: var(--fs-h3); color: var(--paper); letter-spacing: .02em; }
.chapter-band--paper .chapter-band__title { color: var(--graphite); }
.chapter-band__index {
  margin-left: auto;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: rgba(245, 241, 232, .52);
}
.chapter-band--paper .chapter-band__index { color: rgba(58, 65, 73, .5); }

/* ---------- 8. 纸叠卡纸 / 研究板 ---------- */
.paper-card {
  position: relative;
  background: var(--white);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-card);
  padding: clamp(18px, 2.6vw, 28px);
  box-shadow: 8px 8px 0 -1px rgba(58, 65, 73, .07), 8px 8px 0 0 rgba(58, 65, 73, .16);
}
.paper-card--tint { background: var(--paper); }
.paper-card__label {
  display: inline-block;
  margin-bottom: 14px;
  padding: 3px 9px;
  background: var(--paper);
  border: 1px solid var(--line-strong);
  border-radius: 2px;
  font-family: var(--font-narrow);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--slate);
}

.research-panel {
  display: grid;
  gap: 18px;
  padding: clamp(18px, 2.6vw, 26px);
  background: var(--paper);
  border: 1px solid var(--line-strong);
  border-left: 4px solid var(--grass);
}
.research-panel__block { border-top: 1px dashed var(--line); padding-top: 14px; }
.research-panel__block:first-child { border-top: 0; padding-top: 0; }
.research-panel__title {
  margin-bottom: 6px;
  font-family: var(--font-narrow);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--grass);
}

/* ---------- 9. 图片容器（供页面阶段放图） ---------- */
.img-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line-strong);
  background: linear-gradient(135deg, rgba(24, 107, 74, .16), rgba(11, 27, 43, .14));
  aspect-ratio: 16 / 10;
}
.img-frame img { width: 100%; height: 100%; object-fit: cover; }
.img-frame--wide { aspect-ratio: 21 / 9; }
.img-frame--tall { aspect-ratio: 4 / 5; }
.img-frame--square { aspect-ratio: 1 / 1; }
.img-frame__caption {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  padding: 12px 14px 10px;
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--paper);
  background: linear-gradient(0deg, rgba(11, 27, 43, .88), rgba(11, 27, 43, 0));
}

/* ---------- 10. 标签 / 指标 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid var(--line-strong);
  border-radius: 2px;
  background: var(--white);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: var(--slate);
}
.tag--region { background: var(--clay); border-color: var(--clay); color: #fff; }
.tag--data { background: var(--teal); border-color: var(--teal); color: #fff; }
.tag--live { background: var(--signal); border-color: var(--signal); color: #fff; }

.metric {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 12px 0;
  border-top: 1px solid var(--line);
}
.metric__value {
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.4vw, 28px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.03em;
  color: var(--graphite);
}
.metric__label { font-size: 11.5px; letter-spacing: .14em; color: var(--slate); opacity: .72; }

/* ---------- 11. 显现动效基座 ---------- */
[data-reveal] { opacity: 1; }
.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .6s var(--ease), transform .6s var(--ease);
}
.js-ready [data-reveal].is-visible { opacity: 1; transform: none; }

/* ---------- 12. 跳转链接 ---------- */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  padding: 11px 20px;
  background: var(--signal);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  border-radius: 0 0 12px 0;
}
.skip-link:focus { left: 0; }

/* ---------- 13. 头部浮岛 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  padding: 14px var(--gutter) 0;
  background: linear-gradient(180deg, rgba(245, 241, 232, .96) 0%, rgba(245, 241, 232, .74) 52%, rgba(245, 241, 232, 0) 100%);
  transition: padding .3s var(--ease);
}
.site-header[data-condensed="true"] { padding-top: 7px; }

.scroll-progress {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--signal);
  transform: scaleX(0);
  transform-origin: 0 50%;
  opacity: 0;
  z-index: 95;
  transition: transform .12s linear, opacity .25s linear;
}

.nav-shell {
  position: relative;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.4vw, 18px);
  padding: 8px 12px 8px 10px;
  background: var(--night);
  border: 1px solid var(--line-light);
  border-radius: var(--radius-pill);
  box-shadow: 0 18px 40px -26px rgba(11, 27, 43, .95), inset 0 1px 0 rgba(255, 255, 255, .06);
  color: var(--paper);
  transition: max-width .38s var(--ease), padding .3s var(--ease), box-shadow .3s var(--ease);
}
.site-header[data-condensed="true"] .nav-shell {
  max-width: 900px;
  padding-top: 6px;
  padding-bottom: 6px;
  box-shadow: 0 22px 46px -24px rgba(11, 27, 43, 1), inset 0 1px 0 rgba(255, 255, 255, .08);
}

.brand { display: inline-flex; align-items: center; gap: 10px; flex: 0 0 auto; }
.brand__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 12px;
  background: var(--grass);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -.02em;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, .16);
}
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name { font-size: 16px; font-weight: 700; letter-spacing: .05em; color: var(--paper); }
.brand__sub {
  font-family: var(--font-narrow);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: rgba(245, 241, 232, .52);
}

.round-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px 6px 10px;
  border: 1px dashed rgba(245, 241, 232, .3);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: rgba(245, 241, 232, .84);
  white-space: nowrap;
}
.round-badge__dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 3px rgba(255, 107, 44, .18);
  animation: kkPulse 2.4s var(--ease) infinite;
}
.round-badge__text { display: inline-block; }

.nav-current {
  display: none;
  padding-left: 12px;
  margin-left: 2px;
  border-left: 1px solid rgba(245, 241, 232, .22);
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--signal-soft);
  white-space: nowrap;
}
.site-header[data-condensed="true"] .nav-current { display: inline-block; }

.site-nav { margin-left: auto; }
.site-nav__list { display: flex; align-items: center; gap: 2px; }
.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 8px 13px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  color: rgba(245, 241, 232, .76);
  white-space: nowrap;
  transition: color .2s var(--ease), background .2s var(--ease);
}
.site-nav__link:hover { color: var(--paper); background: rgba(245, 241, 232, .09); }
.site-nav__link[aria-current="page"] { color: var(--paper); background: rgba(255, 107, 44, .18); }
.site-nav__link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: var(--signal);
  transform: translateX(-50%);
}
.site-nav__abbr { display: none; }
.site-header[data-condensed="true"] .site-nav__full { display: none; }
.site-header[data-condensed="true"] .site-nav__abbr { display: inline; }

.nav-tools { display: inline-flex; align-items: center; gap: 6px; }
.nav-tool {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 8px 14px;
  border: 1px solid rgba(245, 241, 232, .2);
  border-radius: var(--radius-pill);
  font-size: 13px;
  letter-spacing: .02em;
  color: rgba(245, 241, 232, .86);
  transition: color .2s var(--ease), border-color .2s var(--ease), background .2s var(--ease);
}
.nav-tool:hover { border-color: var(--signal); color: var(--signal-soft); }
.nav-tool--query { background: rgba(24, 107, 74, .62); border-color: rgba(24, 107, 74, .95); color: var(--paper); }
.nav-tool--query:hover { background: rgba(24, 107, 74, .85); color: var(--paper); border-color: var(--grass); }
.nav-tool__icon { font-size: 14px; line-height: 1; }
.fav-count {
  display: inline-grid;
  place-items: center;
  min-width: 20px;
  height: 20px;
  padding: 0 5px;
  border-radius: var(--radius-pill);
  background: var(--signal);
  color: #fff;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: rgba(245, 241, 232, .08);
  border: 1px solid rgba(245, 241, 232, .18);
}
.nav-toggle__bar {
  display: block;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: var(--paper);
  transition: transform .25s var(--ease), opacity .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- 14. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 32px);
  bottom: clamp(14px, 3vw, 32px);
  z-index: 70;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--night);
  color: var(--paper);
  border: 1px solid var(--line-light);
  box-shadow: 0 16px 32px -20px rgba(11, 27, 43, .95);
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity .3s var(--ease), transform .3s var(--ease), background .2s var(--ease);
}
.to-top.is-on { opacity: 1; transform: none; pointer-events: auto; }
.to-top:hover { background: var(--grass); }
.to-top__arrow { font-family: var(--font-mono); font-size: 16px; line-height: 1; }

/* ---------- 15. 页脚 ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  margin-top: clamp(50px, 8vw, 110px);
  padding-top: clamp(38px, 5vw, 64px);
  background-color: var(--night);
  background-image: repeating-linear-gradient(90deg, rgba(245, 241, 232, .07) 0 1px, transparent 1px 26px);
  background-size: 100% 16px;
  background-repeat: repeat-x;
  background-position: left top;
  color: var(--on-dark);
}
.footer-watermark {
  position: absolute;
  right: -3vw;
  bottom: -.14em;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(120px, 22vw, 280px);
  line-height: .75;
  color: rgba(245, 241, 232, .045);
  pointer-events: none;
  user-select: none;
}
.footer-inner {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: grid;
  grid-template-columns: minmax(190px, 1.2fr) repeat(3, minmax(150px, 1fr));
  gap: clamp(26px, 3vw, 48px);
}
.footer-brand { display: flex; flex-direction: column; gap: 14px; }
.brand--footer { display: inline-flex; }
.brand--footer .brand__sub { color: rgba(245, 241, 232, .45); }
.footer-brand__line { font-size: 13px; letter-spacing: .06em; color: rgba(245, 241, 232, .6); max-width: 26ch; }

.footer-title {
  margin-bottom: 14px;
  font-family: var(--font-narrow);
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(245, 241, 232, .48);
}
.footer-lanes { display: flex; flex-direction: column; align-items: flex-start; gap: 9px; }
.footer-lane {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  font-size: 14px;
  color: rgba(245, 241, 232, .84);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.footer-lane::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 1px;
  background: var(--grass);
  transition: background .2s var(--ease);
}
.footer-lane:hover { color: var(--paper); border-color: var(--signal); }
.footer-lane:hover::before { background: var(--signal); }

.footer-contact__list { display: flex; flex-direction: column; gap: 13px; }
.footer-contact__item { display: flex; flex-direction: column; gap: 3px; }
.footer-contact__key { font-size: 10.5px; letter-spacing: .18em; color: rgba(245, 241, 232, .45); }
.footer-contact__value { font-family: var(--font-mono); font-size: 13.5px; color: var(--paper); word-break: break-word; }
.footer-contact__value--text { font-family: var(--font-sans); letter-spacing: .02em; }

.footer-legal { display: flex; flex-direction: column; align-items: flex-start; gap: 10px; }
.footer-legal__link {
  padding-bottom: 1px;
  border-bottom: 1px solid rgba(245, 241, 232, .22);
  font-size: 13.5px;
  color: rgba(245, 241, 232, .78);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.footer-legal__link:hover { color: var(--signal-soft); border-color: var(--signal); }
.footer-legal__note { margin-top: 6px; font-size: 12px; line-height: 1.7; color: rgba(245, 241, 232, .44); max-width: 28ch; }

.footer-base {
  position: relative;
  z-index: 1;
  margin-top: clamp(30px, 4vw, 54px);
  padding: 18px var(--gutter);
  border-top: 1px solid rgba(245, 241, 232, .14);
}
.footer-base__inner {
  max-width: var(--shell);
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 22px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: rgba(245, 241, 232, .55);
}
.footer-icp { color: rgba(245, 241, 232, .68); }
.footer-region { display: inline-flex; align-items: center; gap: 7px; }
.footer-region::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: var(--signal); }
.footer-copy { margin-left: auto; }

/* ---------- 16. 焦点可见 ---------- */
:focus-visible {
  outline: 3px solid rgba(255, 107, 44, .62);
  outline-offset: 2px;
  border-radius: 3px;
}
.nav-shell :focus-visible,
.site-footer :focus-visible,
.to-top:focus-visible { outline-color: var(--signal-soft); }

/* ---------- 17. 关键帧 ---------- */
@keyframes kkPulse {
  0%, 100% { box-shadow: 0 0 0 3px rgba(255, 107, 44, .18); }
  50% { box-shadow: 0 0 0 6px rgba(255, 107, 44, .06); }
}

/* ---------- 18. 响应式 ---------- */
@media (max-width: 1150px) {
  .brand__sub { display: none; }
  .nav-tool__label { display: none; }
  .nav-tool { padding: 8px 11px; }
}
@media (max-width: 1000px) {
  .site-header { padding-top: 10px; }
  .round-badge { display: none; }
  .nav-toggle { display: inline-flex; }
  .nav-current { display: none !important; }
  .site-header[data-condensed="true"] .nav-shell { max-width: 100%; }
  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: calc(100% + 10px);
    margin-left: 0;
    padding: 8px;
    display: none;
    background: var(--night);
    border: 1px solid rgba(245, 241, 232, .16);
    border-radius: 22px;
    box-shadow: 0 28px 54px -30px rgba(11, 27, 43, .98);
  }
  .site-nav[data-open="true"] { display: block; animation: kkDrop .28s var(--ease); }
  .site-nav__list { flex-direction: column; align-items: stretch; gap: 2px; }
  .site-nav__link { justify-content: space-between; padding: 12px 16px; border-radius: 14px; font-size: 15px; }
  .site-nav__link[aria-current="page"]::after {
    left: 6px;
    top: 50%;
    bottom: auto;
    width: 3px;
    height: 18px;
    transform: translateY(-50%);
  }
  .site-header[data-condensed="true"] .site-nav__full { display: inline; }
  .site-header[data-condensed="true"] .site-nav__abbr { display: none; }
  .footer-inner { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 900px) {
  .grid-12 [class^="col-"] { grid-column: 1 / -1; }
}
@media (max-width: 640px) {
  :root { --fs-body: 16px; }
  .nav-shell { padding: 7px 8px 7px 8px; gap: 6px; }
  .brand__mark { width: 34px; height: 34px; border-radius: 10px; font-size: 14px; }
  .brand__name { font-size: 15px; }
  .footer-inner { grid-template-columns: minmax(0, 1fr); }
  .footer-copy { margin-left: 0; }
  .chapter-band__index { margin-left: 0; width: 100%; }
}
@media (max-width: 420px) {
  .nav-tool--fav .nav-tool__label { display: none; }
}

@keyframes kkDrop {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 19. reduced-motion ---------- */
@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-ready [data-reveal] { opacity: 1 !important; transform: none !important; }
  .to-top { transform: none; }
}