/* ============================================================
   半岛手机综合体育 · 共享样式 /assets/site.css
   夜场数据实验室：展览画册式分区 · 极细边界 · 超大数字锚点
   ============================================================ */

/* ---------- 1. Reset ---------- */
*,*::before,*::after{box-sizing:border-box;}
html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:9rem;
}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,figcaption,blockquote,dl,dd{margin:0;padding:0;}
ul,ol{list-style:none;}
img,svg{display:block;max-width:100%;}
img{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%;}

/* ---------- 2. 变量 ---------- */
:root{
  --sea:#071A2F;
  --night:#0B2447;
  --lava:#FF5A1F;
  --turf:#1FBF75;
  --cyan:#4FF0D0;
  --silver:#C7D0DA;
  --paper:#F5F1E8;
  --wine:#6B1F2A;
  --violet:#2E1A5E;
  --mist:#8A97A6;

  --hairline:rgba(199,208,218,.22);
  --hairline-strong:rgba(199,208,218,.45);
  --shadow-soft:0 1px 0 rgba(0,0,0,.35),0 24px 46px -34px rgba(0,0,0,.95);

  --shell:1180px;
  --radius:6px;

  --font-display:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-body:"Helvetica Neue","PingFang SC","Hiragino Sans GB","Noto Sans SC","Microsoft YaHei",system-ui,sans-serif;
  --font-num:"SFMono-Regular",Menlo,Consolas,"Liberation Mono","Courier New",monospace;
}

/* ---------- 3. 中文排版基线 ---------- */
body{
  background-color:var(--sea);
  color:var(--paper);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  letter-spacing:.01em;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:-1;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(199,208,218,.05) 1px,transparent 1px),
    linear-gradient(90deg,rgba(199,208,218,.05) 1px,transparent 1px);
  background-size:88px 88px;
  opacity:.55;
}
h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:900;
  line-height:1.25;
  letter-spacing:.005em;
}
p{line-height:1.85;}
:focus-visible{
  outline:2px solid var(--cyan);
  outline-offset:3px;
  border-radius:2px;
}
.visually-hidden{
  position:absolute;
  width:1px;height:1px;
  margin:-1px;padding:0;border:0;
  clip:rect(0 0 0 0);
  clip-path:inset(50%);
  overflow:hidden;
  white-space:nowrap;
}

/* ---------- 4. Skip link ---------- */
.skip-link{
  position:fixed;
  left:1rem;
  top:-4.5rem;
  z-index:200;
  background:var(--lava);
  color:#08192E;
  font-weight:700;
  font-size:.82rem;
  letter-spacing:.12em;
  padding:.75rem 1.15rem;
  border-radius:4px;
  transition:top .2s ease;
}
.skip-link:focus{top:1rem;}

/* ---------- 5. 页头：居中刊头 + 编号栏目 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:60;
  background:
    radial-gradient(130% 150% at 50% -50%,rgba(255,90,31,.18),transparent 62%),
    linear-gradient(180deg,#071A2F 0%,#0B2447 76%,#08192E 100%);
  border-bottom:1px solid var(--hairline);
  transition:box-shadow .3s ease;
}
.site-header::after{
  content:"";
  position:absolute;
  left:0;right:0;bottom:0;
  height:3px;
  background:linear-gradient(90deg,
    var(--lava) 0 38%,
    var(--cyan) 38% 48%,
    var(--turf) 48% 56%,
    transparent 56% 100%);
  opacity:.9;
  pointer-events:none;
}
.site-header[data-stuck]{box-shadow:0 26px 50px -36px rgba(0,0,0,.98);}
.site-header.is-nav-open{box-shadow:0 26px 50px -30px rgba(0,0,0,.98);}

.header-frame{
  position:relative;
  width:min(var(--shell),100%);
  margin-inline:auto;
  padding:0 clamp(1rem,4vw,2.5rem);
}

.header-status{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:.6rem 1.2rem;
  padding:.6rem 0;
  border-bottom:1px dashed var(--hairline);
}
.season-chip{
  display:inline-flex;
  align-items:center;
  gap:.5rem;
  font-size:.7rem;
  letter-spacing:.16em;
  color:var(--cyan);
  border:1px solid rgba(79,240,208,.34);
  background:rgba(79,240,208,.07);
  padding:.32rem .72rem;
  border-radius:999px;
}
.chip-dot{
  width:6px;height:6px;
  border-radius:50%;
  background:var(--cyan);
  box-shadow:0 0 0 4px rgba(79,240,208,.16);
  animation:chip-pulse 2.6s ease-in-out infinite;
}
@keyframes chip-pulse{
  0%,100%{opacity:1;box-shadow:0 0 0 3px rgba(79,240,208,.16);}
  50%{opacity:.55;box-shadow:0 0 0 7px rgba(79,240,208,.05);}
}
.utility-nav{
  display:flex;
  align-items:center;
  gap:.85rem;
  font-size:.72rem;
  letter-spacing:.16em;
  color:var(--mist);
}
.utility-link{
  color:var(--silver);
  border-bottom:1px solid transparent;
  transition:color .2s ease,border-color .2s ease;
}
.utility-link:hover{color:var(--lava);border-color:var(--lava);}
.utility-sep{
  width:1px;height:12px;
  background:var(--hairline-strong);
  display:inline-block;
}

.masthead{
  text-align:center;
  padding:clamp(.9rem,2.4vw,1.6rem) 0 clamp(.7rem,1.8vw,1.1rem);
}
.masthead-kicker,
.masthead-tagline{
  max-height:2.4rem;
  opacity:1;
  overflow:hidden;
  transition:max-height .28s ease,opacity .22s ease;
}
.masthead-kicker{
  font-family:var(--font-num);
  font-size:.66rem;
  letter-spacing:.46em;
  color:var(--mist);
  text-transform:uppercase;
}
.masthead-brand{
  display:inline-flex;
  align-items:baseline;
  gap:.18em;
  margin-top:.5rem;
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(1.9rem,5.2vw,3.15rem);
  line-height:1;
  letter-spacing:-.02em;
  text-shadow:0 14px 34px rgba(0,0,0,.55);
  transition:font-size .28s ease;
}
.brand-mark{color:var(--lava);}
.brand-word{color:var(--paper);}
.masthead-tagline{
  margin-top:.55rem;
  font-size:.76rem;
  letter-spacing:.3em;
  color:var(--silver);
  opacity:.72;
}
.site-header[data-stuck] .masthead-brand{font-size:clamp(1.5rem,3.6vw,2.05rem);}
.site-header[data-stuck] .masthead{padding-block:.5rem .35rem;}
.site-header[data-stuck] .masthead-kicker,
.site-header[data-stuck] .masthead-tagline{max-height:0;opacity:0;}

.nav-toggle{
  display:none;
  align-items:center;
  justify-content:center;
  gap:.7rem;
  width:100%;
  min-height:46px;
  margin:.4rem 0 .6rem;
  border:1px solid var(--hairline);
  border-radius:4px;
  background:rgba(11,36,71,.62);
  color:var(--paper);
  font-size:.76rem;
  letter-spacing:.26em;
}
.nav-toggle-bars{
  display:inline-flex;
  flex-direction:column;
  justify-content:space-between;
  width:18px;height:12px;
}
.nav-toggle-bars span{
  display:block;
  height:1.5px;
  width:100%;
  background:var(--lava);
  transition:transform .25s ease,opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(1){transform:translateY(5px) rotate(45deg);}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(2){opacity:0;}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:nth-child(3){transform:translateY(-5px) rotate(-45deg);}
.nav-toggle-text{line-height:1;}

.primary-nav{border-top:1px solid var(--hairline);}
.nav-list{
  display:flex;
  flex-wrap:wrap;
  justify-content:center;
  gap:.35rem clamp(.5rem,2.2vw,1.7rem);
}
.nav-item{display:flex;}
.nav-link{
  position:relative;
  display:inline-flex;
  align-items:center;
  gap:.45rem;
  min-height:46px;
  padding:.85rem .3rem;
  font-size:.82rem;
  letter-spacing:.1em;
  color:var(--silver);
  transition:color .22s ease;
}
.nav-link::after{
  content:"";
  position:absolute;
  left:.2rem;right:.2rem;bottom:.5rem;
  height:2px;
  background:var(--lava);
  transform:scaleX(0);
  transform-origin:left center;
  transition:transform .3s ease;
}
.nav-link:hover{color:var(--paper);}
.nav-link:hover::after{transform:scaleX(1);}
.nav-link[aria-current="page"]{color:var(--paper);font-weight:700;}
.nav-link[aria-current="page"]::after{
  transform:scaleX(1);
  background:linear-gradient(90deg,var(--lava),var(--cyan));
}
.nav-index{
  font-family:var(--font-num);
  font-size:.6rem;
  letter-spacing:0;
  color:var(--mist);
  opacity:.85;
}
.nav-link[aria-current="page"] .nav-index{color:var(--cyan);opacity:1;}

.progress-track{
  position:fixed;
  top:0;left:0;right:0;
  height:2px;
  z-index:80;
  background:rgba(199,208,218,.12);
  pointer-events:none;
}
.progress-bar{
  display:block;
  height:100%;
  width:100%;
  transform:scaleX(0);
  transform-origin:left center;
  background:linear-gradient(90deg,var(--lava),var(--cyan));
  transition:transform .12s linear;
}

/* ---------- 6. 页脚：色规 + 四栏 + 状态栏 ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(3rem,8vw,6rem);
  color:var(--silver);
  border-top:1px solid var(--hairline);
  background:
    radial-gradient(90% 130% at 10% 0%,rgba(107,31,42,.55),transparent 62%),
    radial-gradient(80% 130% at 94% 6%,rgba(46,26,94,.6),transparent 60%),
    linear-gradient(180deg,#0B2447 0%,#071A2F 58%,#050F1D 100%);
}
.footer-rule{
  height:4px;
  background:linear-gradient(90deg,
    var(--lava) 0 30%,
    var(--cyan) 30% 38%,
    var(--turf) 38% 46%,
    var(--wine) 46% 72%,
    var(--violet) 72% 100%);
}
.footer-frame{
  width:min(var(--shell),100%);
  margin-inline:auto;
  padding:clamp(2rem,5vw,3.4rem) clamp(1.1rem,4vw,2.5rem) 1.4rem;
}
.footer-grid{
  display:grid;
  gap:clamp(1.5rem,3.6vw,2.6rem);
  grid-template-columns:1.5fr 1fr 1fr 1.35fr;
  align-items:start;
}
.footer-col{min-width:0;}
.footer-kicker{
  font-family:var(--font-num);
  font-size:.66rem;
  letter-spacing:.34em;
  color:var(--cyan);
  opacity:.88;
}
.footer-brand{
  margin-top:.5rem;
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(1.5rem,4.4vw,2.15rem);
  line-height:1.12;
  letter-spacing:-.01em;
  color:var(--paper);
}
.footer-note{
  margin-top:.55rem;
  font-size:.78rem;
  letter-spacing:.1em;
  color:var(--mist);
}
.footer-badge{
  display:inline-flex;
  align-items:center;
  gap:.5rem;
  margin-top:.95rem;
  padding:.36rem .72rem;
  font-size:.72rem;
  color:var(--turf);
  border:1px solid rgba(31,191,117,.36);
  background:rgba(31,191,117,.09);
  border-radius:999px;
}
.badge-dot{
  width:6px;height:6px;
  border-radius:50%;
  background:var(--turf);
}
.footer-heading{
  margin-bottom:.85rem;
  font-family:var(--font-body);
  font-size:.7rem;
  font-weight:600;
  letter-spacing:.3em;
  color:var(--mist);
}
.footer-list{display:flex;flex-direction:column;}
.footer-link{
  display:inline-block;
  padding:.32rem 0;
  font-size:.84rem;
  color:var(--silver);
  border-bottom:1px solid transparent;
  transition:color .2s ease,border-color .2s ease;
}
.footer-link:hover{color:var(--paper);border-color:var(--lava);}
.footer-text{
  font-size:.8rem;
  line-height:1.8;
  color:var(--silver);
}
.footer-text + .footer-text{margin-top:.35rem;}
.footer-text--muted{
  margin-top:.7rem;
  font-size:.74rem;
  color:var(--mist);
}
.footer-meta{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.6rem 1.4rem;
  margin-top:clamp(1.6rem,4vw,2.6rem);
  padding-top:1.1rem;
  border-top:1px solid var(--hairline);
  font-size:.72rem;
  color:var(--mist);
}
.footer-icp{letter-spacing:.06em;}
.footer-copy{letter-spacing:.08em;}
.footer-update{flex:1 1 20rem;line-height:1.7;color:#71808F;}
.to-top{
  margin-left:auto;
  min-height:42px;
  padding:.5rem 1.05rem;
  font-size:.72rem;
  letter-spacing:.16em;
  color:var(--paper);
  background:rgba(11,36,71,.72);
  border:1px solid var(--hairline);
  border-radius:999px;
  transition:color .2s ease,border-color .2s ease,background .2s ease;
}
.to-top:hover{
  color:var(--cyan);
  border-color:rgba(79,240,208,.5);
  background:rgba(79,240,208,.08);
}

/* ---------- 7. 通用容器与分区 ---------- */
.wrap{width:min(var(--shell),calc(100% - clamp(2rem,6vw,3rem)));margin-inline:auto;}
.wrap--narrow{width:min(760px,calc(100% - clamp(2rem,6vw,3rem)));margin-inline:auto;}
.section{padding-block:clamp(2.4rem,6vw,4.6rem);}
.section--paper{
  background:var(--paper);
  color:#22323F;
  border-block:1px solid rgba(11,36,71,.1);
}
.divider{
  height:1px;
  border:0;
  background:var(--hairline);
  margin-block:clamp(1.6rem,4vw,2.6rem);
}

/* ---------- 8. 编号章节 ---------- */
.chapter{
  display:grid;
  grid-template-columns:auto 1fr;
  align-items:end;
  gap:.35rem 1.1rem;
  margin-bottom:clamp(1.4rem,4vw,2.6rem);
}
.chapter-index{
  grid-row:span 2;
  font-family:var(--font-num);
  font-weight:800;
  font-size:clamp(2.4rem,7vw,4.2rem);
  line-height:.85;
  letter-spacing:-.04em;
  color:transparent;
  -webkit-text-stroke:1px var(--hairline-strong);
}
.chapter-title{
  font-size:clamp(1.35rem,3.4vw,2.05rem);
  letter-spacing:-.01em;
  color:var(--paper);
}
.chapter-lead{
  max-width:62ch;
  font-size:.9rem;
  line-height:1.9;
  color:var(--silver);
}

/* ---------- 9. 网格与卡片 ---------- */
.grid{display:grid;gap:clamp(.9rem,2.2vw,1.4rem);}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr));}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(228px,1fr));}
.card{
  position:relative;
  padding:clamp(1.1rem,2.6vw,1.6rem);
  background:linear-gradient(160deg,rgba(11,36,71,.94),rgba(7,26,47,.94));
  border:1px solid var(--hairline);
  border-radius:var(--radius);
  box-shadow:var(--shadow-soft);
}
.card--lava{border-color:rgba(255,90,31,.4);}
.card--cyan{border-color:rgba(79,240,208,.34);}

/* ---------- 10. 按钮与标签 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  gap:.5rem;
  min-height:46px;
  padding:.75rem 1.35rem;
  border:1px solid transparent;
  border-radius:3px;
  font-size:.82rem;
  font-weight:700;
  letter-spacing:.14em;
  transition:transform .2s ease,background .2s ease,color .2s ease,border-color .2s ease;
}
.btn--lava{background:var(--lava);color:#08192E;}
.btn--lava:hover{background:#FF7A46;transform:translateY(-1px);}
.btn--ghost{
  background:rgba(11,36,71,.55);
  border-color:var(--hairline);
  color:var(--paper);
}
.btn--ghost:hover{border-color:rgba(79,240,208,.55);color:var(--cyan);}

.tag{
  display:inline-flex;
  align-items:center;
  gap:.4rem;
  padding:.3rem .68rem;
  border:1px solid var(--hairline);
  border-radius:999px;
  font-size:.68rem;
  letter-spacing:.16em;
  color:var(--silver);
}
.tag--lava{color:var(--lava);border-color:rgba(255,90,31,.42);}
.tag--turf{color:var(--turf);border-color:rgba(31,191,117,.42);}
.tag--cyan{color:var(--cyan);border-color:rgba(79,240,208,.42);}
.tag--wine{color:#E7A9B3;border-color:rgba(107,31,42,.75);background:rgba(107,31,42,.28);}

.link-inline{
  color:var(--cyan);
  border-bottom:1px solid rgba(79,240,208,.42);
  transition:color .2s ease,border-color .2s ease;
}
.link-inline:hover{color:var(--paper);border-color:var(--paper);}

/* ---------- 11. 数据锚点 ---------- */
.num{
  font-family:var(--font-num);
  font-variant-numeric:tabular-nums;
  letter-spacing:-.02em;
}
.stat{display:flex;flex-direction:column;gap:.35rem;}
.stat-value{
  font-family:var(--font-num);
  font-weight:800;
  font-size:clamp(2.1rem,7vw,3.5rem);
  line-height:1;
  letter-spacing:-.035em;
  color:var(--paper);
}
.stat-label{
  font-size:.72rem;
  letter-spacing:.2em;
  color:var(--mist);
}
.stat--cyan .stat-value{color:var(--cyan);}
.stat--lava .stat-value{color:var(--lava);}
.stat--turf .stat-value{color:var(--turf);}

/* ---------- 12. 面包屑 ---------- */
.breadcrumbs ol{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.45rem;
  font-size:.74rem;
  letter-spacing:.12em;
  color:var(--mist);
}
.breadcrumbs li{display:inline-flex;align-items:center;gap:.45rem;}
.breadcrumbs li + li::before{
  content:"⁄";
  color:var(--lava);
}
.breadcrumbs a{color:var(--mist);transition:color .2s ease;}
.breadcrumbs a:hover{color:var(--cyan);}
.breadcrumbs [aria-current="page"]{color:var(--silver);}

/* ---------- 13. 长文 ---------- */
.prose{
  max-width:68ch;
  font-size:1rem;
  line-height:1.95;
  color:var(--silver);
}
.prose > * + *{margin-top:1.1em;}
.prose h2,.prose h3{
  font-family:var(--font-display);
  line-height:1.35;
  color:var(--paper);
}
.prose h2{font-size:clamp(1.25rem,2.6vw,1.6rem);margin-top:1.9em;}
.prose h3{font-size:1.06rem;margin-top:1.5em;}
.prose p{line-height:1.95;}
.prose a{
  color:var(--cyan);
  border-bottom:1px solid rgba(79,240,208,.4);
}
.prose strong{color:var(--paper);font-weight:700;}
.prose ul{display:block;}
.prose ul li{
  position:relative;
  margin-top:.55em;
  padding-left:1.15rem;
}
.prose ul li::before{
  content:"";
  position:absolute;
  left:0;top:.78em;
  width:.55rem;height:1px;
  background:var(--lava);
}
.prose blockquote{
  padding-left:1.1rem;
  border-left:2px solid var(--lava);
  font-family:var(--font-display);
  color:var(--paper);
}
.prose code{
  font-family:var(--font-num);
  font-size:.9em;
  color:var(--cyan);
}

/* ---------- 14. 响应式图片容器 ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  aspect-ratio:16 / 10;
  border:1px solid var(--hairline);
  border-radius:var(--radius);
  background:
    radial-gradient(120% 120% at 20% 0%,rgba(11,36,71,.95),transparent 70%),
    linear-gradient(150deg,#0B2447,#071A2F);
}
.media-frame--wide{aspect-ratio:21 / 9;}
.media-frame--tall{aspect-ratio:3 / 4;}
.media-frame img{
  width:100%;
  height:100%;
  object-fit:cover;
  filter:saturate(1.06) contrast(1.06);
}
.media-frame--grain::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background:repeating-linear-gradient(0deg,rgba(245,241,232,.05) 0 1px,transparent 1px 3px);
  mix-blend-mode:overlay;
}

/* ---------- 15. 筛选条 ---------- */
.filter-bar{
  display:flex;
  flex-wrap:wrap;
  gap:.5rem;
  margin-bottom:clamp(1.1rem,3vw,1.7rem);
}
.filter-btn{
  min-height:42px;
  padding:.5rem 1.05rem;
  font-size:.76rem;
  letter-spacing:.14em;
  color:var(--silver);
  background:rgba(11,36,71,.5);
  border:1px solid var(--hairline);
  border-radius:999px;
  transition:color .2s ease,border-color .2s ease,background .2s ease;
}
.filter-btn:hover{color:var(--cyan);border-color:rgba(79,240,208,.5);}
.filter-btn[aria-pressed="true"]{
  background:var(--lava);
  border-color:var(--lava);
  color:#08192E;
  font-weight:700;
}
[data-filter-item].is-filtered-out{display:none;}

/* ---------- 16. 显现动效 ---------- */
html[data-js="on"] [data-reveal]{
  opacity:0;
  transform:translateY(16px);
  transition:opacity .6s ease,transform .6s ease;
}
html[data-js="on"] [data-reveal].is-revealed{
  opacity:1;
  transform:none;
}

/* ---------- 17. 浅色分区覆盖 ---------- */
.section--paper .chapter-index{-webkit-text-stroke-color:rgba(11,36,71,.35);}
.section--paper .chapter-title{color:#0B2447;}
.section--paper .chapter-lead{color:#4A5A6B;}
.section--paper .divider{background:rgba(11,36,71,.14);}
.section--paper .card{
  background:#FFFFFF;
  border-color:rgba(11,36,71,.14);
  box-shadow:0 1px 0 rgba(11,36,71,.06),0 22px 40px -34px rgba(11,36,71,.6);
}
.section--paper .stat-value{color:#0B2447;}
.section--paper .stat--cyan .stat-value{color:#0E8C7C;}
.section--paper .stat--lava .stat-value{color:#C43C0C;}
.section--paper .stat--turf .stat-value{color:#128553;}
.section--paper .stat-label{color:#6B7A8A;}
.section--paper .prose{color:#33475C;}
.section--paper .prose h2,
.section--paper .prose h3,
.section--paper .prose strong{color:#0B2447;}
.section--paper .prose a{color:#0E7D6F;border-bottom-color:rgba(14,125,111,.45);}
.section--paper .tag{border-color:rgba(11,36,71,.2);color:#3E4E5E;}
.section--paper .tag--lava{color:#C43C0C;border-color:rgba(196,60,12,.4);}
.section--paper .tag--turf{color:#128553;border-color:rgba(18,133,83,.4);}
.section--paper .tag--cyan{color:#0E8C7C;border-color:rgba(14,140,124,.4);}
.section--paper .btn--ghost{background:#FFFFFF;border-color:rgba(11,36,71,.2);color:#0B2447;}
.section--paper .btn--ghost:hover{border-color:var(--lava);color:var(--lava);}
.section--paper .media-frame{border-color:rgba(11,36,71,.16);}

/* ---------- 18. 断点 ---------- */
@media (max-width:1024px){
  .footer-grid{grid-template-columns:1fr 1fr;}
}
@media (max-width:880px){
  html{scroll-padding-top:7rem;}
  .header-status{flex-wrap:wrap;justify-content:space-between;}
  .utility-nav{display:none;}
  .nav-toggle{display:inline-flex;}
  .primary-nav{
    position:absolute;
    left:0;right:0;top:100%;
    max-height:0;
    overflow:hidden;
    border-top:1px solid var(--hairline);
    border-bottom:1px solid var(--hairline);
    background:linear-gradient(180deg,#0B2447,#071A2F);
    box-shadow:0 34px 54px -34px rgba(0,0,0,.98);
    transition:max-height .32s ease;
  }
  .primary-nav[data-open]{
    max-height:min(72vh,620px);
    overflow-y:auto;
  }
  .nav-list{
    flex-direction:column;
    flex-wrap:nowrap;
    gap:0;
    padding:.4rem 1rem 1rem;
  }
  .nav-item{border-bottom:1px dashed var(--hairline);}
  .nav-item:last-child{border-bottom:0;}
  .nav-link{
    width:100%;
    min-height:52px;
    padding:1rem .25rem;
    font-size:.95rem;
  }
  .nav-link::after{
    left:.25rem;right:auto;
    width:2.6rem;
    bottom:.55rem;
  }
  .footer-link{min-height:44px;padding:.7rem 0;}
  .footer-meta{align-items:flex-start;}
  .to-top{margin-left:0;}
}
@media (max-width:640px){
  .footer-grid{grid-template-columns:1fr;}
  .chapter{grid-template-columns:1fr;gap:.3rem;}
  .chapter-index{grid-row:auto;}
  .progress-track{height:2px;}
}

/* ---------- 19. 动效偏好 ---------- */
@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;
  }
  html[data-js="on"] [data-reveal]{
    opacity:1;
    transform:none;
  }
  .chip-dot{animation:none;}
}