/* ========== 1. 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,figure,blockquote,dl,dd,ul,ol{margin:0}
ul,ol{padding:0}
h1,h2,h3,h4,h5,h6{font-size:inherit;font-weight:inherit}
img,svg,video{display:block;max-width:100%;height:auto}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;padding:0}
a{color:#2B57B8;text-decoration:underline;text-underline-offset:.22em;text-decoration-thickness:1.5px}
a:hover{color:#D6402F}
[id]{scroll-margin-top:132px}

/* ========== 2. 变量 ========== */
:root{
  --indigo:#101A3A;
  --indigo-deep:#0A1230;
  --indigo-lift:#1A2752;
  --ink:#241A16;
  --paper:#F6EBD2;
  --paper-2:#EFE1C2;
  --red:#D6402F;
  --yellow:#F2B544;
  --green:#2F8F6B;
  --blue:#3C6FD6;
  --white:#FFFDF7;
  --slate:#8FA1C7;
  --rust:#C45A2C;

  --font-display:"Bahnschrift SemiBold","Bahnschrift","Arial Black","Haettenschweiler","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-serif:"Songti SC","Source Han Serif SC","Noto Serif SC",Georgia,"SimSun",serif;
  --font-body:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","Noto Sans SC",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",Menlo,Consolas,"Liberation Mono","Courier New",monospace;

  --shell:1180px;
  --shell-wide:1340px;
  --shell-narrow:760px;
  --pad:clamp(16px,3.4vw,40px);
  --gap:clamp(16px,2.4vw,32px);
  --radius:18px;
  --radius-pill:999px;
  --shadow-paper:0 1px 0 rgba(36,26,22,.1),0 16px 30px -20px rgba(16,26,58,.55);
  --shadow-lift:0 2px 0 rgba(36,26,22,.12),0 26px 44px -22px rgba(16,26,58,.6);
  --ease:cubic-bezier(.22,.68,.28,1);
}

/* ========== 3. 基础排版 ========== */
body{
  min-height:100vh;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:clamp(15px,1vw,16.5px);
  line-height:1.78;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4,h5,h6{font-family:var(--font-display);font-weight:800;line-height:1.08;letter-spacing:-.02em}
h1{font-size:clamp(2.3rem,5.6vw,4.4rem)}
h2{font-size:clamp(1.65rem,3.2vw,2.7rem)}
h3{font-size:clamp(1.12rem,1.7vw,1.45rem);letter-spacing:-.01em;line-height:1.25}
h4{font-size:1.02rem;letter-spacing:0}
p{max-width:72ch}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.04em}
.eyebrow{
  display:inline-flex;align-items:center;gap:.7em;
  font-family:var(--font-mono);font-size:.72rem;font-weight:600;
  letter-spacing:.22em;text-transform:uppercase;color:var(--rust);
}
.eyebrow::before{content:"";width:28px;height:3px;background:var(--red);display:block;flex:0 0 auto}
.lede{
  font-family:var(--font-serif);font-size:clamp(1.04rem,1.6vw,1.32rem);
  line-height:1.72;color:rgba(36,26,22,.82);max-width:60ch;
}
.visually-hidden{
  position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0;
}

/* ========== 4. 跳转与焦点 ========== */
.skip-link{
  position:absolute;left:50%;top:0;z-index:200;
  transform:translate(-50%,-150%);
  padding:.72em 1.3em;border-radius:0 0 14px 14px;
  background:var(--yellow);color:var(--ink);
  font-family:var(--font-mono);font-size:.82rem;font-weight:700;letter-spacing:.06em;
  text-decoration:none;box-shadow:0 6px 18px -8px rgba(10,18,48,.9);
  transition:transform .2s var(--ease);
}
.skip-link:focus,.skip-link:focus-visible{transform:translate(-50%,0);color:var(--ink)}
:focus-visible{outline:3px solid var(--yellow);outline-offset:3px;border-radius:5px}
.site-footer :focus-visible,.site-header :focus-visible{outline-color:var(--yellow)}

/* ========== 5. 布局容器 ========== */
.container{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:var(--pad)}
.container--wide{max-width:var(--shell-wide)}
.container--narrow{max-width:var(--shell-narrow)}
.section{position:relative;padding-block:clamp(44px,6vw,88px)}
.section--tight{padding-block:clamp(26px,3.6vw,52px)}
.section--paper{
  background-color:var(--paper);
  background-image:
    repeating-linear-gradient(0deg,rgba(36,26,22,.035) 0 1px,transparent 1px 5px),
    radial-gradient(circle at 16% 10%,rgba(196,90,44,.08),transparent 44%);
}
.section--indigo{
  background-color:var(--indigo);color:var(--white);
  background-image:
    repeating-linear-gradient(45deg,rgba(143,161,199,.07) 0 1px,transparent 1px 20px),
    radial-gradient(circle at 86% 6%,rgba(60,111,214,.38),transparent 48%),
    radial-gradient(circle at 8% 94%,rgba(214,64,47,.22),transparent 52%);
}
.section--ink{background-color:var(--ink);color:var(--paper)}
.section--indigo .eyebrow,.section--ink .eyebrow{color:var(--yellow)}
.section--indigo .lede,.section--ink .lede{color:rgba(255,253,247,.84)}
.section--indigo a,.section--ink a{color:var(--yellow)}
.stack>*+*{margin-top:clamp(12px,1.6vw,20px)}
.cluster{display:flex;flex-wrap:wrap;align-items:center;gap:.7em}
.section-head{
  display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;
  gap:clamp(14px,2vw,28px);margin-bottom:clamp(22px,3vw,40px);
}

/* ========== 6. 栅格 ========== */
.grid{display:grid;gap:var(--gap)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}
.grid--auto{grid-template-columns:repeat(auto-fit,minmax(min(100%,260px),1fr))}
@media (max-width:960px){
  .grid--3,.grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:620px){
  .grid--2,.grid--3,.grid--4{grid-template-columns:minmax(0,1fr)}
}

/* ========== 7. 按钮 ========== */
.btn{
  --btn-bg:var(--ink);--btn-fg:var(--paper);--btn-bd:transparent;
  display:inline-flex;align-items:center;justify-content:center;gap:.55em;
  padding:.74em 1.45em;border-radius:var(--radius-pill);
  background:var(--btn-bg);color:var(--btn-fg);border:2px solid var(--btn-bd);
  font-family:var(--font-body);font-size:.94rem;font-weight:700;letter-spacing:.02em;
  text-decoration:none;cursor:pointer;white-space:nowrap;
  box-shadow:0 3px 0 rgba(36,26,22,.22);
  transition:transform .18s var(--ease),box-shadow .2s var(--ease),background-color .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.btn:hover{transform:translateY(-2px);box-shadow:0 7px 0 -2px rgba(36,26,22,.22)}
.btn:active{transform:translateY(1px);box-shadow:0 1px 0 rgba(36,26,22,.2)}
.btn--primary{--btn-bg:var(--red);--btn-fg:var(--white);box-shadow:0 3px 0 rgba(122,32,22,.4)}
.btn--primary:hover{box-shadow:0 7px 0 -2px rgba(122,32,22,.4)}
.btn--ghost{--btn-bg:transparent;--btn-fg:var(--ink);--btn-bd:rgba(36,26,22,.4);box-shadow:none}
.btn--ghost:hover{--btn-bd:var(--ink);box-shadow:none}
.section--indigo .btn--ghost,.section--ink .btn--ghost{--btn-fg:var(--white);--btn-bd:rgba(255,253,247,.5);color:var(--white)}
.section--indigo .btn--ghost:hover,.section--ink .btn--ghost:hover{--btn-bd:var(--yellow);color:var(--yellow)}
.btn--light{--btn-bg:var(--paper);--btn-fg:var(--indigo)}
.btn-row{display:flex;flex-wrap:wrap;gap:.8em}

/* ========== 8. 标签 ========== */
.tag{
  display:inline-flex;align-items:center;gap:.42em;
  padding:.3em .78em;border-radius:var(--radius-pill);
  border:1px solid rgba(36,26,22,.24);background:var(--paper);color:var(--ink);
  font-family:var(--font-mono);font-size:.72rem;font-weight:600;
  letter-spacing:.08em;text-transform:uppercase;white-space:nowrap;
}
.tag--red{background:rgba(214,64,47,.12);border-color:rgba(214,64,47,.5);color:#8E2A1E}
.tag--yellow{background:rgba(242,181,68,.3);border-color:rgba(196,90,44,.45);color:#77420F}
.tag--green{background:rgba(47,143,107,.14);border-color:rgba(47,143,107,.48);color:#1E6448}
.tag--blue{background:rgba(60,111,214,.14);border-color:rgba(60,111,214,.48);color:#25489B}
.tag--solid{background:var(--ink);border-color:var(--ink);color:var(--paper)}

/* ========== 9. 章节编号 ========== */
.chapter{
  display:grid;grid-template-columns:auto minmax(0,1fr);
  gap:clamp(12px,2vw,26px);align-items:start;
}
.chapter__num{
  font-family:var(--font-serif);font-weight:700;font-size:clamp(2.6rem,6.4vw,4.8rem);
  line-height:.78;letter-spacing:-.05em;color:var(--red);
  font-variant-numeric:tabular-nums;
}
.chapter__title{font-family:var(--font-display);font-size:clamp(1.3rem,2.4vw,1.9rem);font-weight:800;line-height:1.14;margin:0}
.chapter__note{
  margin-top:.5em;font-family:var(--font-mono);font-size:.74rem;
  letter-spacing:.16em;text-transform:uppercase;color:rgba(36,26,22,.62);
}
.section--indigo .chapter__num{color:var(--yellow)}
.section--indigo .chapter__note{color:rgba(255,253,247,.6)}

/* ========== 10. 卡片与展签 ========== */
.card{
  position:relative;isolation:isolate;
  background:var(--white);border:1px solid rgba(36,26,22,.16);
  border-radius:var(--radius);padding:clamp(18px,2.3vw,28px);
  box-shadow:5px 5px 0 0 rgba(36,26,22,.1),var(--shadow-paper);
  transition:transform .22s var(--ease),box-shadow .22s var(--ease);
}
.card:hover{transform:translate(-2px,-2px);box-shadow:8px 8px 0 0 rgba(36,26,22,.12),var(--shadow-lift)}
.card--label{
  background:var(--paper);
  border-left:5px solid var(--red);
  border-radius:4px 16px 16px 4px;
  box-shadow:4px 4px 0 0 rgba(36,26,22,.09);
}
.card__code{
  font-family:var(--font-mono);font-size:.7rem;font-weight:600;
  letter-spacing:.18em;text-transform:uppercase;color:var(--rust);
}
.card__title{font-family:var(--font-display);font-size:1.14rem;font-weight:800;line-height:1.25;margin:.4em 0 .45em}
.card__body{font-size:.95rem;color:rgba(36,26,22,.8)}
.card__meta{
  display:flex;flex-wrap:wrap;gap:.5em;margin-top:1em;
  font-family:var(--font-mono);font-size:.72rem;letter-spacing:.06em;color:rgba(36,26,22,.6);
}
.section--indigo .card{background:var(--indigo-lift);color:var(--white);border-color:rgba(143,161,199,.3);box-shadow:5px 5px 0 0 rgba(5,10,28,.5)}
.section--indigo .card__body{color:rgba(255,253,247,.82)}
.section--indigo .card__code{color:var(--yellow)}
.section--indigo .card__meta{color:var(--slate)}

/* ========== 11. 提示块与键值表 ========== */
.callout{
  display:grid;grid-template-columns:auto minmax(0,1fr);gap:14px;
  padding:16px 18px;border-radius:12px;
  background:rgba(242,181,68,.16);border:1px solid rgba(196,90,44,.35);
  font-size:.95rem;
}
.callout__mark{font-family:var(--font-mono);font-weight:700;color:var(--rust);letter-spacing:.06em}
.callout--tip{background:rgba(47,143,107,.12);border-color:rgba(47,143,107,.42)}
.callout--tip .callout__mark{color:#1E6448}
.callout--warn{background:rgba(214,64,47,.1);border-color:rgba(214,64,47,.42)}
.callout--warn .callout__mark{color:#8E2A1E}
.kv{display:grid;grid-template-columns:minmax(76px,auto) minmax(0,1fr);gap:.45em 1.1em;font-size:.92rem}
.kv dt{font-family:var(--font-mono);font-size:.76rem;letter-spacing:.1em;text-transform:uppercase;color:rgba(36,26,22,.6)}
.kv dd{margin:0;font-family:var(--font-mono);font-weight:600;color:var(--ink);word-break:break-word}
.section--indigo .kv dt{color:var(--slate)}
.section--indigo .kv dd{color:var(--white)}

/* ========== 12. 分隔线 / 经幡条 ========== */
.rule{height:0;border:0;border-top:1px dashed rgba(36,26,22,.32);margin-block:clamp(20px,3vw,36px)}
.rule-flags{
  height:6px;border-radius:3px;
  background:linear-gradient(90deg,
    var(--blue) 0 20%,var(--white) 20% 40%,var(--red) 40% 60%,
    var(--green) 60% 80%,var(--yellow) 80% 100%);
  box-shadow:0 1px 0 rgba(36,26,22,.2);
}

/* ========== 13. 面包屑 ========== */
.breadcrumbs{
  display:flex;flex-wrap:wrap;align-items:center;gap:.55em;
  padding-block:14px;
  font-family:var(--font-mono);font-size:.74rem;letter-spacing:.06em;color:rgba(36,26,22,.62);
}
.breadcrumbs a{color:inherit;text-decoration:none;border-bottom:1px solid rgba(36,26,22,.28)}
.breadcrumbs a:hover{color:var(--rust);border-bottom-color:var(--rust)}
.breadcrumbs__sep{color:rgba(36,26,22,.36)}
.breadcrumbs__current{color:var(--ink);font-weight:700}
.section--indigo .breadcrumbs{color:rgba(255,253,247,.66)}
.section--indigo .breadcrumbs a{border-bottom-color:rgba(255,253,247,.3)}
.section--indigo .breadcrumbs__current{color:var(--white)}

/* ========== 14. 图片容器基础 ========== */
.media-frame{
  position:relative;overflow:hidden;isolation:isolate;
  border-radius:var(--radius);border:1px solid rgba(36,26,22,.2);
  aspect-ratio:16/9;background-color:var(--indigo);
  background-image:
    repeating-linear-gradient(0deg,rgba(143,161,199,.16) 0 1px,transparent 1px 14px),
    repeating-linear-gradient(90deg,rgba(143,161,199,.16) 0 1px,transparent 1px 14px),
    radial-gradient(circle at 28% 22%,rgba(60,111,214,.55),transparent 56%),
    radial-gradient(circle at 78% 84%,rgba(214,64,47,.42),transparent 58%);
  box-shadow:6px 6px 0 0 rgba(36,26,22,.1);
}
.media-frame > img,.media-frame__img{display:block;width:100%;height:100%;object-fit:cover}
.media-frame--1x1{aspect-ratio:1/1}
.media-frame--4x3{aspect-ratio:4/3}
.media-frame--3x4{aspect-ratio:3/4}
.media-frame--wide{aspect-ratio:21/9}
.media-frame__caption{
  position:absolute;left:0;right:0;bottom:0;z-index:2;
  padding:12px 16px;
  background:linear-gradient(180deg,transparent,rgba(10,18,48,.88));
  color:var(--white);font-family:var(--font-mono);font-size:.72rem;letter-spacing:.08em;
}
.media-frame__badge{
  position:absolute;top:12px;left:12px;z-index:2;
  padding:.32em .78em;border-radius:var(--radius-pill);
  background:var(--paper);color:var(--ink);
  font-family:var(--font-mono);font-size:.68rem;font-weight:700;letter-spacing:.1em;
  box-shadow:0 2px 0 rgba(36,26,22,.22);
}

/* ========== 15. 经幡色块（共用） ========== */
.flag{display:block;flex:1 1 0;min-width:0}
.flag--blue{background:var(--blue)}
.flag--white{background:var(--white)}
.flag--red{background:var(--red)}
.flag--green{background:var(--green)}
.flag--yellow{background:var(--yellow)}

/* ========== 16. 头部 ========== */
.site-header{
  position:sticky;top:0;z-index:90;
  background:linear-gradient(180deg,var(--indigo) 0%,var(--indigo) 82%,rgba(16,26,58,0) 100%);
  color:var(--white);
  padding-bottom:12px;
}
.flag-bar{display:flex;height:5px;overflow:hidden;transition:height .3s var(--ease)}
.site-header.is-scrolled .flag-bar{height:3px}
.header-shell{
  position:relative;
  width:100%;max-width:var(--shell-wide);margin-inline:auto;
  padding:12px var(--pad);
  display:flex;align-items:center;gap:clamp(8px,1.1vw,16px);
  transition:padding .3s var(--ease);
}
.site-header.is-scrolled .header-shell{padding-block:6px}

/* 品牌岛 */
.brand{
  display:inline-flex;align-items:center;gap:.72em;flex:0 0 auto;
  padding:6px 15px 6px 6px;border-radius:var(--radius-pill);
  background:rgba(255,253,247,.07);border:1px solid rgba(143,161,199,.3);
  color:var(--white);text-decoration:none;
  transition:background-color .2s var(--ease),border-color .2s var(--ease),transform .2s var(--ease);
}
.brand:hover{background:rgba(255,253,247,.13);border-color:rgba(242,181,68,.62);transform:translateY(-1px);color:var(--white)}
.brand__seal{
  width:34px;height:34px;flex:0 0 auto;display:grid;place-items:center;
  border-radius:9px;background:var(--red);color:var(--white);
  font-family:var(--font-serif);font-weight:700;font-size:1.04rem;line-height:1;
  transform:rotate(-4deg);box-shadow:0 2px 0 rgba(10,18,48,.55);
}
.brand__text{display:flex;flex-direction:column;line-height:1.12;min-width:0}
.brand__name{font-family:var(--font-display);font-weight:800;font-size:1rem;letter-spacing:.02em;color:var(--white);white-space:nowrap}
.brand__tagline{font-family:var(--font-mono);font-size:.6rem;letter-spacing:.2em;color:var(--slate);text-transform:uppercase;white-space:nowrap}

/* 栏目胶囊岛 */
.site-nav{
  display:flex;align-items:center;margin-inline:auto;
  padding:5px;border-radius:var(--radius-pill);
  background:rgba(255,253,247,.06);
  border:1px solid rgba(143,161,199,.3);
  box-shadow:inset 0 1px 0 rgba(255,253,247,.1);
}
.nav-list{display:flex;align-items:center;gap:2px;list-style:none;margin:0;padding:0}
.nav-link{
  display:inline-flex;align-items:center;
  padding:7px 13px;border-radius:var(--radius-pill);
  color:rgba(255,253,247,.82);text-decoration:none;
  font-size:.9rem;font-weight:600;letter-spacing:.02em;white-space:nowrap;
  transition:color .18s var(--ease),background-color .18s var(--ease),box-shadow .18s var(--ease);
}
.nav-link:hover{color:var(--white);background:rgba(255,253,247,.12)}
.nav-link[aria-current="page"]{
  background:var(--yellow);color:var(--ink);font-weight:700;
  box-shadow:0 2px 0 rgba(10,18,48,.4);
}
.nav-quick{display:none}

/* 快捷展签 */
.header-tools{display:flex;align-items:center;gap:8px;flex:0 0 auto}
.tool-link{
  display:inline-flex;align-items:center;justify-content:center;
  padding:7px 13px;border-radius:var(--radius-pill);
  font-family:var(--font-mono);font-size:.73rem;font-weight:600;letter-spacing:.08em;
  color:rgba(255,253,247,.86);text-decoration:none;
  border:1px solid rgba(143,161,199,.42);background:transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease),background-color .18s var(--ease),transform .18s var(--ease);
}
.tool-link:hover{color:var(--white);border-color:var(--yellow);transform:translateY(-1px)}
.tool-link--key{background:var(--red);border-color:var(--red);color:var(--white);font-weight:700}
.tool-link--key:hover{background:#B93A2A;border-color:#B93A2A;color:var(--white)}

/* 移动端按钮 */
.nav-toggle{
  display:none;align-items:center;gap:.6em;flex:0 0 auto;
  padding:8px 14px;border-radius:var(--radius-pill);
  background:rgba(255,253,247,.1);border:1px solid rgba(143,161,199,.42);
  color:var(--white);cursor:pointer;
  font-family:var(--font-mono);font-size:.73rem;font-weight:600;letter-spacing:.14em;
  transition:background-color .2s var(--ease),border-color .2s var(--ease);
}
.nav-toggle:hover{background:rgba(255,253,247,.18);border-color:rgba(242,181,68,.6)}
.nav-toggle__bars{display:grid;gap:3px;width:18px}
.nav-toggle__bars span{display:block;height:2px;border-radius:2px;background:currentColor;transition:transform .22s var(--ease),opacity .18s var(--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__label{line-height:1}

/* 滚动进度 */
.scroll-meter{
  position:absolute;left:0;right:0;bottom:0;height:3px;
  background:rgba(143,161,199,.16);pointer-events:none;
}
.scroll-meter__bar{
  display:block;height:100%;width:0;
  background:linear-gradient(90deg,var(--blue) 0%,var(--white) 26%,var(--red) 52%,var(--green) 76%,var(--yellow) 100%);
  transition:width .12s linear;
}

/* ========== 17. 页脚 ========== */
.site-footer{
  position:relative;margin-top:auto;overflow:hidden;
  background-color:var(--indigo-deep);color:var(--white);
  background-image:
    repeating-linear-gradient(90deg,rgba(143,161,199,.075) 0 1px,transparent 1px 26px),
    repeating-linear-gradient(0deg,rgba(143,161,199,.055) 0 1px,transparent 1px 26px),
    radial-gradient(circle at 88% 0%,rgba(60,111,214,.4),transparent 50%),
    radial-gradient(circle at 4% 96%,rgba(214,64,47,.24),transparent 54%);
}
.footer-flags{display:flex;height:8px}
.footer-shell{
  width:100%;max-width:var(--shell-wide);margin-inline:auto;
  padding:clamp(36px,5vw,66px) var(--pad) clamp(18px,2.4vw,26px);
}
.footer-top{
  display:grid;grid-template-columns:1.7fr 1fr 1fr 1.25fr;
  gap:clamp(22px,3vw,46px);
}
.footer-brand{min-width:0}
.footer-brand__head{display:flex;align-items:center;gap:.72em}
.footer-brand__seal{
  width:38px;height:38px;flex:0 0 auto;display:grid;place-items:center;
  border-radius:10px;background:var(--red);color:var(--white);
  font-family:var(--font-serif);font-weight:700;font-size:1.1rem;line-height:1;
  transform:rotate(-4deg);box-shadow:0 2px 0 rgba(0,0,0,.4);
}
.footer-brand__name{
  font-family:var(--font-display);font-size:1.14rem;font-weight:800;
  letter-spacing:.02em;color:var(--white);margin:0;
}
.footer-brand__summary{
  margin-top:1em;max-width:36ch;
  font-size:.92rem;line-height:1.85;color:rgba(255,253,247,.72);
}
.footer-brand__code{
  margin-top:1.1em;
  font-family:var(--font-mono);font-size:.7rem;letter-spacing:.16em;
  text-transform:uppercase;color:var(--slate);
}
.footer-col{min-width:0}
.footer-col__title{
  display:flex;align-items:center;gap:.6em;
  margin:0 0 1em;
  font-family:var(--font-mono);font-size:.72rem;font-weight:700;
  letter-spacing:.2em;text-transform:uppercase;color:var(--yellow);
}
.footer-col__title::before{
  content:"";width:10px;height:10px;flex:0 0 auto;
  background:var(--yellow);box-shadow:2px 2px 0 rgba(0,0,0,.4);
}
.footer-list{list-style:none;margin:0;padding:0;display:grid;gap:.6em}
.footer-link{
  color:rgba(255,253,247,.78);text-decoration:none;font-size:.92rem;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.footer-link:hover{color:var(--yellow);border-bottom-color:rgba(242,181,68,.65)}
.footer-contact{min-width:0}
.footer-contact__list{list-style:none;margin:0;padding:0;display:grid;gap:.9em;font-size:.9rem}
.footer-contact__label{
  display:block;
  font-family:var(--font-mono);font-size:.66rem;font-weight:600;
  letter-spacing:.18em;text-transform:uppercase;color:var(--slate);margin-bottom:.15em;
}
.footer-contact__val{
  font-family:var(--font-mono);font-size:.86rem;color:var(--white);
  word-break:break-word;line-height:1.6;
}
.footer-bottom{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:12px 26px;
  margin-top:clamp(28px,4vw,50px);padding-top:clamp(16px,2vw,24px);
  border-top:1px solid rgba(143,161,199,.26);
  font-family:var(--font-mono);font-size:.72rem;letter-spacing:.08em;
  color:rgba(255,253,247,.6);
}
.footer-note{margin:0;max-width:none}
.footer-legal{display:flex;flex-wrap:wrap;gap:8px 18px;list-style:none;margin:0;padding:0}
.footer-legal .footer-link{font-size:.72rem;color:rgba(255,253,247,.66)}
.footer-icp{margin:0;color:rgba(255,253,247,.72)}

/* ========== 18. 动效 ========== */
[data-reveal]{
  opacity:0;transform:translateY(22px);
  transition:opacity .62s var(--ease),transform .62s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
  will-change:opacity,transform;
}
[data-reveal].is-revealed{opacity:1;transform:none;will-change:auto}

/* ========== 19. 响应式 ========== */
@media (max-width:1080px){
  .footer-top{grid-template-columns:1.4fr 1fr 1fr;gap:clamp(20px,2.6vw,34px)}
  .footer-contact{grid-column:1 / -1}
  .footer-contact__list{grid-template-columns:repeat(auto-fit,minmax(200px,1fr))}
}
@media (max-width:980px){
  .site-nav{
    position:absolute;top:calc(100% + 8px);left:var(--pad);right:var(--pad);
    display:block;margin-inline:0;padding:12px;
    border-radius:22px;background:var(--indigo-deep);
    border:1px solid rgba(143,161,199,.34);
    box-shadow:0 26px 52px -26px rgba(3,8,24,.95);
    max-height:calc(100vh - 150px);overflow-y:auto;
    opacity:0;visibility:hidden;transform:translateY(-10px);pointer-events:none;
    transition:opacity .2s var(--ease),transform .24s var(--ease),visibility .2s var(--ease);
  }
  .site-nav[data-open]{
    opacity:1;visibility:visible;transform:none;pointer-events:auto;
  }
  .nav-list{flex-direction:column;align-items:stretch;gap:4px}
  .nav-link{
    justify-content:space-between;padding:12px 14px;border-radius:12px;
    font-size:1rem;border:1px solid rgba(143,161,199,.14);
  }
  .nav-quick{
    display:grid;gap:8px;margin-top:10px;padding-top:10px;
    border-top:1px dashed rgba(143,161,199,.32);
  }
  .nav-quick .tool-link{padding:11px 14px;font-size:.78rem}
  .header-tools{display:none}
  .nav-toggle{display:inline-flex;margin-left:auto}
  .brand__tagline{display:none}
}
@media (max-width:760px){
  .footer-top{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand{grid-column:1 / -1}
  .footer-contact{grid-column:1 / -1}
  .footer-bottom{flex-direction:column;align-items:flex-start}
  .chapter{grid-template-columns:minmax(0,1fr)}
  .chapter__num{font-size:clamp(2.4rem,12vw,3.4rem)}
}
@media (max-width:520px){
  .brand{padding-right:10px}
  .brand__name{font-size:.94rem}
  .brand__seal{width:30px;height:30px;font-size:.95rem}
  .footer-top{grid-template-columns:minmax(0,1fr)}
  .footer-contact__list{grid-template-columns:minmax(0,1fr)}
}

/* ========== 20. 减弱动画 ========== */
@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;
  }
  [data-reveal]{opacity:1!important;transform:none!important}
  .btn:hover,.card:hover,.brand:hover,.tool-link:hover{transform:none}
}