/* ==========================================================================
   28圈品牌 · 共享样式 /assets/site.css
   视觉语言“脉冲导航”：墨海基底 + 电光青路径 + 暖橙行动点 + 岩灰细线框
   ========================================================================== */

/* 1. 设计令牌 ------------------------------------------------------------- */
:root{
  /* 品牌色板 */
  --ink-900:#06121C;
  --ink-800:#0A1B2A;
  --ink-750:#0E2233;
  --cyan:#2FD8C8;
  --cyan-soft:#8AF0E6;
  --orange:#FF8A3D;
  --orange-deep:#E8722A;
  --clay:#B85C3A;
  --moss:#5E8C74;
  --rock:#33475A;
  --rock-soft:#26374A;
  --cream:#F4F0E8;
  --paper:#FBF9F5;
  --fog:#93A6B5;

  /* 语义变量 */
  --bg:var(--ink-800);
  --line:var(--rock);
  --text:#E9EFF3;
  --text-soft:#C7D4DC;
  --text-dim:var(--fog);

  /* 形状 */
  --radius-xl:28px;
  --radius-lg:22px;
  --radius-md:18px;
  --radius-sm:12px;
  --pill:999px;

  /* 网格与节奏 */
  --shell:1200px;
  --gutter:clamp(1rem,4vw,2.5rem);
  --header-h:80px;
  --header-h-shrink:64px;

  /* 字体 */
  --font-display:'Barlow Condensed','Oswald','Noto Sans SC','PingFang SC','Microsoft YaHei',sans-serif;
  --font-body:'Noto Sans SC','PingFang SC','Microsoft YaHei',system-ui,-apple-system,sans-serif;
  --font-mono:'JetBrains Mono','SFMono-Regular',Consolas,'Courier New',monospace;

  --ease:cubic-bezier(.22,.68,.32,1);
}

/* 2. 基础重置与中文排版 --------------------------------------------------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:var(--font-body);
  font-size:16.5px;
  font-weight:400;
  line-height:1.9;
  letter-spacing:.005em;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4{
  margin:0 0 .6em;
  font-family:var(--font-display);
  font-weight:700;
  line-height:1.16;
  letter-spacing:.01em;
  color:var(--paper);
  text-wrap:balance;
}
h1{font-size:clamp(2rem,4.4vw,3.8rem);font-weight:800}
h2{font-size:clamp(1.55rem,2.6vw,2.3rem)}
h3{font-size:clamp(1.18rem,1.8vw,1.5rem)}
h4{font-size:1.05rem}
p{margin:0 0 1em}
a{color:var(--cyan);text-decoration:none}
a:hover{color:var(--cyan-soft)}
ul,ol{margin:0 0 1em;padding-left:1.2em}
li{margin-bottom:.35em}
img,svg,video{display:block;max-width:100%}
img{height:auto}
button,input,select,textarea{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:4px}
::selection{background:rgba(47,216,200,.28);color:var(--paper)}
body[data-nav-open]{overflow:hidden}

/* 3. 容器与骨架 ----------------------------------------------------------- */
.shell{width:min(100% - (var(--gutter) * 2),var(--shell));margin-inline:auto}
.shell--narrow{width:min(100% - (var(--gutter) * 2),760px);margin-inline:auto}
.shell--wide{width:min(100% - (var(--gutter) * 2),1440px);margin-inline:auto}
.page-top{padding-top:calc(var(--header-h) + clamp(1.2rem,3vw,2.4rem))}

.section{position:relative;padding:clamp(3.5rem,8vw,6.5rem) 0}
.section--tight{padding:clamp(2.2rem,5vw,3.4rem) 0}
.section--deep{background:var(--ink-900)}
.section--light{background:var(--cream);color:#2A3F4F}
.section--light h1,.section--light h2,.section--light h3,.section--light h4{color:var(--ink-800)}
.section--light .lede{color:#3E5566}
.section--light .eyebrow{color:var(--clay)}
.section--light .eyebrow::before{background:linear-gradient(90deg,transparent,var(--clay))}
.section--light p a,.section--light li a,.section--light .prose a{color:var(--clay)}
.section--light p a:hover,.section--light li a:hover,.section--light .prose a:hover{color:#8F4426}
.section--light .meta,.section--light .mono,.section--light .section-num{color:#5B6E7C}

/* 4. 网格 ---------------------------------------------------------------- */
.grid{display:grid;gap:clamp(1rem,2.2vw,1.6rem)}
.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--asym{grid-template-columns:minmax(230px,.85fr) minmax(0,1.7fr)}
@media (max-width:1000px){
  .grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:900px){
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .grid--asym{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:680px){
  .grid--2,.grid--3,.grid--4{grid-template-columns:minmax(0,1fr)}
}

/* 5. 文字语言 ------------------------------------------------------------ */
.display{
  font-family:var(--font-display);
  font-size:clamp(2.1rem,4.6vw,4rem);
  font-weight:800;
  line-height:1.08;
  letter-spacing:.01em;
  margin:0 0 .55em;
  color:var(--paper);
  text-wrap:balance;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  margin:0 0 1rem;
  font-family:var(--font-mono);
  font-size:11.5px;
  font-weight:500;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--cyan);
}
.eyebrow::before{content:"";width:26px;height:1px;background:linear-gradient(90deg,transparent,var(--cyan))}
.lede{font-size:clamp(1rem,1.5vw,1.16rem);line-height:1.85;color:var(--text-soft);max-width:60ch;margin:0 0 1.2em}
.mono{font-family:var(--font-mono);font-size:12.5px;letter-spacing:.06em}
.meta{font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--fog);margin:0 0 .6em}
.section-num{display:block;margin-bottom:.7rem;font-family:var(--font-mono);font-size:12px;letter-spacing:.16em;color:var(--cyan)}
.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  justify-content:space-between;
  gap:18px;
  margin-bottom:clamp(1.4rem,3vw,2.4rem);
}
.section-head__text{max-width:62ch;min-width:0}
.link{
  color:var(--cyan);
  border-bottom:1px solid rgba(47,216,200,.35);
  padding-bottom:1px;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.link:hover{color:var(--cyan-soft);border-color:var(--cyan-soft)}

.prose{max-width:68ch}
.prose h2{margin-top:2.1em}
.prose h3{margin-top:1.7em}
.prose p,.prose li{font-size:16.5px;color:var(--text-soft)}
.prose ul,.prose ol{padding-left:1.3em}
.prose blockquote{
  margin:1.6em 0;
  padding:.2em 0 .2em 1.1em;
  border-left:2px solid var(--clay);
  color:#AEC0CC;
}
.section--light .prose p,.section--light .prose li{color:#33475A}
.section--light .prose blockquote{color:#4A6070}

/* 6. 按钮、胶囊与标签 ---------------------------------------------------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:13px 22px;
  border:1px solid transparent;
  border-radius:var(--pill);
  font-family:var(--font-body);
  font-size:15px;
  font-weight:600;
  line-height:1;
  text-decoration:none;
  white-space:nowrap;
  cursor:pointer;
  transition:transform .18s var(--ease),background-color .18s var(--ease),
             border-color .18s var(--ease),color .18s var(--ease);
}
.btn--primary{background:var(--orange);border-color:var(--orange);color:#2A1206}
.btn--primary:hover{background:var(--orange-deep);border-color:var(--orange-deep);color:#2A1206;transform:translateY(-2px)}
.btn--ghost{background:transparent;border-color:var(--rock);color:var(--cream)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan-soft);transform:translateY(-2px)}
.btn--cyan{background:var(--cyan);border-color:var(--cyan);color:var(--ink-900)}
.btn--cyan:hover{background:var(--cyan-soft);border-color:var(--cyan-soft);color:var(--ink-900);transform:translateY(-2px)}
.btn--sm{padding:9px 16px;font-size:13.5px}
.btn--block{width:100%}

.chip{
  display:inline-flex;
  align-items:center;
  gap:7px;
  padding:7px 13px;
  border:1px solid var(--rock);
  border-radius:var(--pill);
  background:transparent;
  color:var(--fog);
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
  text-decoration:none;
  transition:border-color .18s var(--ease),color .18s var(--ease),background-color .18s var(--ease);
}
.chip:hover{border-color:var(--cyan);color:var(--cyan-soft)}
.chip--ghost:hover{background:rgba(47,216,200,.1)}
.chip--cyan{border-color:rgba(47,216,200,.35);background:rgba(47,216,200,.08);color:var(--cyan-soft)}
.chip--moss{border-color:rgba(94,140,116,.5);background:rgba(94,140,116,.14);color:#A8CDB9}
.chip--clay{border-color:rgba(184,92,58,.5);background:rgba(184,92,58,.14);color:#E7AC8F}

.tag{
  display:inline-block;
  padding:3px 9px;
  border:1px solid rgba(94,140,116,.35);
  border-radius:6px;
  background:rgba(94,140,116,.18);
  color:#A8CDB9;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
}
.tag--cyan{border-color:rgba(47,216,200,.35);background:rgba(47,216,200,.12);color:var(--cyan-soft)}
.tag--clay{border-color:rgba(184,92,58,.4);background:rgba(184,92,58,.16);color:#E7AC8F}

/* 7. 卡片、步骤、提示 ---------------------------------------------------- */
.card{
  position:relative;
  padding:clamp(1.1rem,2vw,1.6rem);
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  background:rgba(255,255,255,.02);
  transition:border-color .22s var(--ease),background-color .22s var(--ease);
}
.card__head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:.9rem}
.card__title{
  margin:0 0 .4rem;
  font-family:var(--font-display);
  font-size:clamp(1.08rem,1.6vw,1.32rem);
  font-weight:700;
  color:var(--paper);
  transition:color .22s var(--ease);
}
.card__body{margin:0;font-size:15.5px;color:#B9C7D1}
.card__foot{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  margin-top:1.1rem;
  padding-top:.9rem;
  border-top:1px solid var(--rock-soft);
}
.card--link{display:block;color:inherit;text-decoration:none}
.card--link:hover{border-color:var(--cyan);background:rgba(47,216,200,.05)}
.card--link:hover .card__title{color:var(--cyan-soft)}
.section--light .card{background:var(--paper);border-color:#DCD5C7}
.section--light .card__title{color:var(--ink-800)}
.section--light .card__body{color:#3E5566}
.section--light .card--link:hover{border-color:var(--clay);background:#FFFFFF}
.section--light .card--link:hover .card__title{color:var(--clay)}

.step-list{display:grid;gap:14px;margin:0;padding:0;list-style:none}
.step{
  display:grid;
  grid-template-columns:auto 1fr;
  gap:16px;
  align-items:start;
  padding:16px 18px;
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  background:rgba(255,255,255,.02);
  transition:border-color .22s var(--ease);
}
.step:hover{border-color:var(--cyan)}
.step__num{
  padding:4px 11px;
  border:1px solid rgba(47,216,200,.35);
  border-radius:var(--pill);
  background:rgba(47,216,200,.08);
  color:var(--cyan);
  font-family:var(--font-mono);
  font-size:13px;
  font-weight:600;
  line-height:1.5;
  letter-spacing:.06em;
}
.step__title{margin:0 0 .2rem;font-family:var(--font-display);font-size:1.05rem;font-weight:700;color:var(--paper)}
.step__text{margin:0;font-size:15px;color:#B9C7D1}

.note{
  max-width:58ch;
  margin:1.4rem 0;
  padding:2px 0 2px 16px;
  border-left:2px solid var(--cyan);
  font-size:15px;
  color:#B9C7D1;
}
.note__label{
  display:block;
  margin-bottom:.35rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--cyan);
}
.aside{padding-top:.9rem;border-top:1px solid var(--rock-soft);font-size:14.5px;color:var(--fog)}
.aside__label{
  display:block;
  margin-bottom:.4rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--moss);
}

/* 8. 图片容器（页面阶段放图） -------------------------------------------- */
.media-frame{
  position:relative;
  isolation:isolate;
  overflow:hidden;
  aspect-ratio:var(--media-ratio,16/9);
  border:1px solid var(--line);
  border-radius:var(--radius-lg);
  background:linear-gradient(135deg,var(--ink-900),var(--ink-750));
}
.media-frame > img,
.media-frame > svg,
.media-frame > video{width:100%;height:100%;object-fit:cover}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(to right,rgba(47,216,200,.07) 1px,transparent 1px),
    linear-gradient(to bottom,rgba(47,216,200,.07) 1px,transparent 1px);
  background-size:48px 48px;
}
.media-frame--plain::after{display:none}
.media-frame--r16x9{--media-ratio:16/9}
.media-frame--r4x3{--media-ratio:4/3}
.media-frame--r1x1{--media-ratio:1/1}
.media-frame--r3x4{--media-ratio:3/4}
.media-frame__caption{
  position:absolute;
  left:16px;
  bottom:14px;
  z-index:2;
  padding:5px 12px;
  border:1px solid rgba(47,216,200,.3);
  border-radius:var(--pill);
  background:rgba(6,18,28,.72);
  color:var(--cyan-soft);
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
}

/* 9. 分隔线、面包屑、规范图形 -------------------------------------------- */
.rule{height:1px;margin:clamp(1.6rem,4vw,3rem) 0;border:0;background:var(--line)}
.rule--pulse{
  height:8px;
  background-image:repeating-linear-gradient(90deg,var(--cyan) 0 1px,transparent 1px 14px);
  opacity:.5;
}
.breadcrumb{margin:0 0 1.2rem}
.breadcrumb__list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:6px;
  margin:0;
  padding:0;
  list-style:none;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.08em;
}
.breadcrumb__item{display:flex;align-items:center;gap:6px;color:var(--fog);margin:0}
.breadcrumb__item + .breadcrumb__item::before{content:"/";color:var(--rock)}
.breadcrumb__item[aria-current="page"]{color:var(--cyan-soft)}
.breadcrumb__link{color:var(--fog);text-decoration:none;transition:color .2s var(--ease)}
.breadcrumb__link:hover{color:var(--cyan)}

/* 10. 标签面板与折叠块 ---------------------------------------------------- */
.tabs__list{display:flex;flex-wrap:wrap;gap:8px;margin:0 0 1.4rem;padding:0;list-style:none}
.tab{
  padding:9px 16px;
  border:1px solid var(--rock);
  border-radius:var(--pill);
  background:transparent;
  color:var(--fog);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.08em;
  cursor:pointer;
  transition:border-color .2s var(--ease),color .2s var(--ease),background-color .2s var(--ease);
}
.tab:hover{border-color:var(--cyan);color:var(--cyan-soft)}
.tab[aria-selected="true"]{border-color:var(--cyan);background:rgba(47,216,200,.12);color:var(--cyan-soft)}
.tabs__panel[hidden]{display:none}

.fold{
  margin:0 0 12px;
  border:1px solid var(--line);
  border-radius:var(--radius-md);
  background:rgba(255,255,255,.02);
  overflow:hidden;
  transition:border-color .22s var(--ease);
}
.fold[open]{border-color:rgba(47,216,200,.4)}
.fold__summary{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  padding:16px 20px;
  list-style:none;
  cursor:pointer;
  font-family:var(--font-display);
  font-size:1.08rem;
  font-weight:700;
  color:var(--paper);
  transition:color .2s var(--ease);
}
.fold__summary::-webkit-details-marker{display:none}
.fold__summary::after{
  content:"+";
  font-family:var(--font-mono);
  font-size:18px;
  color:var(--cyan);
  transition:transform .22s var(--ease);
}
.fold[open] .fold__summary::after{content:"–"}
.fold__summary:hover{color:var(--cyan-soft)}
.fold__body{padding:0 20px 18px;font-size:15.5px;color:#B9C7D1}

/* 11. 显现动画 ----------------------------------------------------------- */
.reveal-ready [data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .5s var(--ease),transform .5s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
}
.reveal-ready [data-reveal].is-visible{opacity:1;transform:none}

/* 12. 跳转链接 ----------------------------------------------------------- */
.skip-link{
  position:absolute;
  top:.5rem;
  left:50%;
  z-index:130;
  padding:.6rem 1.1rem;
  border-radius:var(--pill);
  background:var(--cyan);
  color:var(--ink-900);
  font-weight:600;
  text-decoration:none;
  transform:translate(-50%,-200%);
  transition:transform .2s var(--ease);
}
.skip-link:focus{transform:translate(-50%,0);color:var(--ink-900)}

/* 13. 头部 --------------------------------------------------------------- */
.site-header{
  position:fixed;
  inset:0 0 auto;
  z-index:100;
  background:linear-gradient(180deg,rgba(6,18,28,.86),rgba(6,18,28,.3));
  backdrop-filter:blur(14px) saturate(140%);
  transition:background-color .3s var(--ease),box-shadow .3s var(--ease);
}
.site-header::after{
  content:"";
  position:absolute;
  inset:auto 0 0;
  height:1px;
  background:transparent;
  transition:background-color .3s var(--ease);
}
.site-header[data-scrolled="true"]{
  background:var(--ink-900);
  box-shadow:0 18px 40px -32px rgba(0,0,0,.9);
}
.site-header[data-scrolled="true"]::after{background:var(--rock)}
.site-header__inner{
  display:flex;
  align-items:center;
  gap:clamp(12px,2vw,28px);
  min-height:var(--header-h);
  transition:min-height .3s var(--ease);
}
.site-header[data-scrolled="true"] .site-header__inner{min-height:var(--header-h-shrink)}

.pulse-bar{
  position:fixed;
  top:0;
  left:0;
  z-index:110;
  width:100%;
  height:2px;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
  transform:scaleX(0);
  transform-origin:left;
  pointer-events:none;
  transition:transform .12s linear;
}

/* 品牌 */
.brand{display:flex;align-items:center;gap:14px;flex:0 0 auto;min-width:0}
.brand__link{display:flex;align-items:center;gap:12px;color:var(--paper);text-decoration:none}
.brand__mark{
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  border:1px solid rgba(47,216,200,.28);
  border-radius:var(--radius-sm);
  background:rgba(47,216,200,.09);
  color:var(--cyan);
  flex:0 0 auto;
}
.brand__node{fill:var(--orange)}
.brand__text{display:flex;flex-direction:column;line-height:1.25;min-width:0}
.brand__name{font-family:var(--font-display);font-size:20px;font-weight:700;letter-spacing:.03em;color:var(--paper)}
.brand__meta{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.12em;text-transform:uppercase;color:var(--fog)}
.version-chip{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 10px;
  border:1px solid rgba(47,216,200,.3);
  border-radius:var(--pill);
  color:var(--cyan-soft);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  white-space:nowrap;
}
.version-chip__dot{
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--cyan);
  box-shadow:0 0 0 3px rgba(47,216,200,.16);
}

/* 移动导航按钮 */
.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  margin-left:auto;
  padding:8px 14px;
  border:1px solid var(--rock);
  border-radius:var(--pill);
  background:transparent;
  color:var(--paper);
  cursor:pointer;
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);color:var(--cyan-soft)}
.nav-toggle__bars{display:grid;gap:4px;width:16px}
.nav-toggle__bars span{display:block;height:2px;border-radius:2px;background:currentColor;transition:transform .22s var(--ease)}
.site-header[data-open="true"] .nav-toggle__bars span:first-child{transform:translateY(3px) rotate(45deg)}
.site-header[data-open="true"] .nav-toggle__bars span:last-child{transform:translateY(-3px) rotate(-45deg)}
.nav-toggle__label{font-family:var(--font-mono);font-size:11px;letter-spacing:.12em}

/* 主导航 */
.site-nav{display:flex;align-items:center;gap:16px;flex:1 1 auto;min-width:0}
.site-nav__list{
  display:flex;
  align-items:center;
  gap:2px;
  flex:1 1 auto;
  margin:0 0 0 clamp(6px,1.6vw,26px);
  padding:0;
  list-style:none;
}
.site-nav__list li{margin:0}
.site-nav__link{
  position:relative;
  display:inline-block;
  padding:9px 12px;
  border-radius:10px;
  color:var(--fog);
  font-size:15px;
  font-weight:500;
  text-decoration:none;
  transition:color .2s var(--ease),background-color .2s var(--ease);
}
.site-nav__link::after{
  content:"";
  position:absolute;
  left:12px;
  right:12px;
  bottom:3px;
  height:2px;
  border-radius:2px;
  background:var(--cyan);
  transform:scaleX(0);
  transform-origin:left;
  transition:transform .22s var(--ease);
}
.site-nav__link:hover{color:var(--paper)}
.site-nav__link:hover::after{transform:scaleX(1)}
.site-nav__link[aria-current="page"]{color:var(--paper);background:rgba(47,216,200,.08)}
.site-nav__link[aria-current="page"]::after{transform:scaleX(1)}
.site-nav__actions{display:flex;align-items:center;gap:10px;margin-left:auto}

/* 14. 页脚 --------------------------------------------------------------- */
.site-footer{
  padding:clamp(2.6rem,6vw,4.5rem) 0 2rem;
  border-top:1px solid var(--rock);
  background:var(--ink-900);
  color:var(--fog);
  font-size:15px;
}
.site-footer__grid{
  display:grid;
  grid-template-columns:1.4fr 1fr 1.25fr 1fr;
  gap:clamp(1.6rem,3vw,3rem);
}
.footer-col{min-width:0}
.footer-brand{
  display:inline-flex;
  align-items:center;
  gap:12px;
  margin-bottom:1rem;
  color:var(--paper);
  text-decoration:none;
}
.footer-tagline{
  margin:0 0 .7rem;
  font-family:var(--font-display);
  font-size:1.22rem;
  font-weight:700;
  line-height:1.45;
  color:var(--paper);
}
.footer-note{margin:0;max-width:34ch;font-size:14.5px;color:var(--fog)}
.footer-title{
  margin:0 0 1rem;
  font-family:var(--font-mono);
  font-size:11.5px;
  font-weight:500;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--cyan);
}
.footer-list{display:grid;gap:9px;margin:0;padding:0;list-style:none}
.footer-list li{margin:0}
.footer-link{color:var(--fog);text-decoration:none;transition:color .2s var(--ease)}
.footer-link:hover{color:var(--cyan-soft)}
.footer-label{
  display:block;
  margin-bottom:2px;
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.14em;
  text-transform:uppercase;
  color:var(--moss);
}
.footer-value{display:block;font-size:14.5px;color:#B9C7D1;word-break:break-word}
.footer-value--mono{font-family:var(--font-mono);letter-spacing:.04em}
.site-footer__bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px 24px;
  margin-top:clamp(2rem,5vw,3rem);
  padding-top:1.4rem;
  border-top:1px solid var(--rock-soft);
}
.footer-copy{margin:0;font-size:13px;color:var(--fog)}
.footer-icp{
  margin:0;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--fog);
}

/* 15. 响应式 ------------------------------------------------------------- */
@media (max-width:1100px){
  .site-footer__grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:980px){
  :root{--header-h:68px;--header-h-shrink:60px}
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:absolute;
    top:100%;
    left:0;
    right:0;
    display:none;
    flex-direction:column;
    align-items:stretch;
    gap:0;
    max-height:calc(100vh - var(--header-h));
    overflow-y:auto;
    padding:12px var(--gutter) 22px;
    border-top:1px solid var(--rock);
    border-bottom:1px solid var(--rock);
    background:var(--ink-900);
  }
  .site-header[data-open="true"] .site-nav{display:flex}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0;margin:0}
  .site-nav__link{display:block;padding:14px 12px;border-bottom:1px solid var(--rock-soft);border-radius:0;font-size:16px}
  .site-nav__link::after{display:none}
  .site-nav__link[aria-current="page"]{background:transparent;color:var(--cyan-soft)}
  .site-nav__actions{flex-direction:column;align-items:stretch;gap:10px;margin:18px 0 0}
  .site-nav__actions .btn,.site-nav__actions .chip{justify-content:center}
  .brand__meta{display:none}
}
@media (max-width:640px){
  .version-chip{display:none}
  .brand__mark{width:36px;height:36px}
  .brand__name{font-size:18px}
  .site-footer__grid{grid-template-columns:minmax(0,1fr)}
  .site-footer__bottom{flex-direction:column;align-items:flex-start}
  .step{grid-template-columns:minmax(0,1fr);gap:10px}
}

/* 16. 无障碍与低动效 ----------------------------------------------------- */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .reveal-ready [data-reveal]{opacity:1;transform:none}
  .btn:hover,.chip:hover{transform:none}
}