:root{
  --ink:#071A14;
  --ink-2:#0C2A20;
  --cyan:#2FF3D0;
  --cyan-dim:#14B8A6;
  --orange:#FF6A2A;
  --orange-soft:#FFB089;
  --paper:#F4EBDD;
  --paper-edge:#D9C9B0;
  --brown:#1B1712;
  --white:#F7FBF8;
  --rail:88px;
  --line:rgba(47,243,208,.22);
  --line-soft:rgba(247,251,248,.14);
  --muted:rgba(247,251,248,.66);
  --font-body:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-display:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;
  --ease:cubic-bezier(.22,.68,.26,1);
  --scroll-progress:0;
}
*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;}
body{
  margin:0;
  background:var(--ink);
  color:var(--white);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.7;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
}
body::after{
  content:"";
  position:fixed;
  top:0;left:0;
  width:100%;
  height:2px;
  z-index:120;
  pointer-events:none;
  opacity:.9;
  background:linear-gradient(90deg,var(--cyan) 0,var(--cyan) calc(var(--scroll-progress,0) * 1%),transparent calc(var(--scroll-progress,0) * 1%),transparent 100%);
}
img,svg{max-width:100%;}
h1,h2,h3,h4,p,ul,ol,figure{margin:0;}
ul,ol{padding:0;list-style:none;}
a{color:inherit;}
button{font:inherit;color:inherit;}
::selection{background:var(--cyan);color:var(--ink);}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;}

/* ============ 通用排版工具 ============ */
.container{width:100%;max-width:1240px;margin:0 auto;padding:0 24px;}
.section{padding:64px 0;}
.mono{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-feature-settings:"tnum" 1;
  letter-spacing:.02em;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--cyan);
}
.eyebrow::before{content:"";flex:0 0 20px;width:20px;height:1px;background:currentColor;}
.grid-12{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:24px;}
.breadcrumb{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  padding:18px 0;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  color:var(--muted);
}
.breadcrumb a{color:var(--cyan-dim);text-decoration:none;}
.breadcrumb a:hover{color:var(--cyan);}
.breadcrumb li{display:inline-flex;align-items:center;gap:8px;}
.breadcrumb li:not(:last-child)::after{content:"/";color:rgba(247,251,248,.32);}

/* ============ 按钮 ============ */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  min-height:46px;
  padding:11px 22px;
  border:1px solid var(--line);
  background:transparent;
  color:var(--white);
  font-family:var(--font-body);
  font-size:14px;
  font-weight:600;
  letter-spacing:.06em;
  line-height:1.2;
  text-decoration:none;
  cursor:pointer;
  transition:background-color .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease),transform .2s var(--ease);
}
.btn:hover{transform:translateY(-2px);}
.btn--primary{background:var(--orange);border-color:var(--orange);color:var(--brown);}
.btn--primary:hover{background:var(--orange-soft);border-color:var(--orange-soft);}
.btn--ghost{color:var(--cyan);border-color:rgba(47,243,208,.45);}
.btn--ghost:hover{background:rgba(47,243,208,.12);border-color:var(--cyan);}

/* ============ 卡片 / 标签 / 纸面 ============ */
.card{
  position:relative;
  padding:22px;
  background:var(--ink-2);
  border:1px solid var(--line-soft);
  transition:transform .26s var(--ease),border-color .26s var(--ease),box-shadow .26s var(--ease);
}
.card:hover{
  transform:translateY(-3px);
  border-color:rgba(47,243,208,.5);
  box-shadow:0 14px 34px rgba(0,0,0,.42);
}
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 9px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  line-height:1.4;
  border:1px solid currentColor;
}
.tag--current{color:var(--cyan);}
.tag--archive{color:var(--brown);background:var(--orange);border-color:var(--orange);}
.paper{
  padding:28px;
  background-color:var(--paper);
  background-image:repeating-linear-gradient(0deg,rgba(27,23,18,.045) 0 1px,transparent 1px 5px);
  color:var(--brown);
  border:1px solid var(--paper-edge);
  box-shadow:inset 0 0 0 1px rgba(255,255,255,.5);
}
.paper a{color:#9A3412;}

/* ============ 图片容器基础 ============ */
.media-frame{
  position:relative;
  display:block;
  overflow:hidden;
  background:var(--ink-2);
  border:1px solid var(--line-soft);
}
.media-frame::before{
  content:"";
  position:absolute;
  inset:0;
  z-index:2;
  pointer-events:none;
  background:repeating-linear-gradient(0deg,rgba(47,243,208,.06) 0 1px,transparent 1px 4px);
  opacity:.7;
}
.media-frame img,
.media-frame__fill{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
}
.media-frame__fill{
  background-image:
    linear-gradient(90deg,rgba(47,243,208,.14) 1px,transparent 1px),
    linear-gradient(0deg,rgba(47,243,208,.14) 1px,transparent 1px),
    radial-gradient(circle at 28% 24%,rgba(47,243,208,.2),transparent 62%);
  background-size:48px 48px,48px 48px,100% 100%;
  background-color:var(--ink-2);
}
.media-frame[data-ratio="21x9"]{aspect-ratio:21/9;}
.media-frame[data-ratio="16x9"]{aspect-ratio:16/9;}
.media-frame[data-ratio="4x3"]{aspect-ratio:4/3;}
.media-frame[data-ratio="3x2"]{aspect-ratio:3/2;}
.media-frame[data-ratio="1x1"]{aspect-ratio:1/1;}

/* ============ 滚动显现协议 ============ */
[data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .42s var(--ease),transform .42s var(--ease);
}
[data-reveal].is-revealed{opacity:1;transform:none;}

/* ============ 跳转链接 ============ */
.skip-link{
  position:fixed;
  top:-120px;
  left:12px;
  z-index:200;
  padding:10px 18px;
  background:var(--cyan);
  color:var(--ink);
  font-size:13px;
  font-weight:700;
  letter-spacing:.04em;
  text-decoration:none;
  transition:top .2s var(--ease);
}
.skip-link:focus{top:12px;}

/* ============ 头部：侧边轨道 ============ */
.site-rail{
  position:fixed;
  top:0;left:0;bottom:0;
  z-index:90;
  width:var(--rail);
  display:flex;
  flex-direction:column;
  align-items:center;
  gap:16px;
  padding:16px 8px 14px;
  background:var(--ink);
  border-right:1px solid var(--line);
  overflow-y:auto;
  overscroll-behavior:contain;
  scrollbar-width:none;
}
.site-rail::-webkit-scrollbar{width:0;height:0;}
.rail-head{display:flex;flex-direction:column;align-items:center;gap:12px;width:100%;}
.brand{
  display:flex;
  flex-direction:column;
  align-items:center;
  gap:10px;
  padding:2px;
  color:var(--white);
  text-decoration:none;
}
.brand-mark{
  display:grid;
  place-items:center;
  width:38px;height:38px;
  background:rgba(47,243,208,.06);
  border:1px solid var(--cyan);
  color:var(--cyan);
  font-size:17px;
  font-weight:700;
  line-height:1;
  letter-spacing:0;
  transition:background-color .2s var(--ease),color .2s var(--ease);
}
.brand:hover .brand-mark{background:var(--cyan);color:var(--ink);}
.brand-name{
  writing-mode:vertical-rl;
  text-orientation:mixed;
  font-size:12.5px;
  font-weight:700;
  line-height:1.1;
  letter-spacing:.3em;
  color:var(--white);
}
.rail-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:9px 12px;
  background:rgba(47,243,208,.06);
  border:1px solid var(--line);
  color:var(--cyan);
  font-size:12px;
  letter-spacing:.14em;
  cursor:pointer;
}
.rail-toggle-bars{display:inline-flex;flex-direction:column;gap:4px;width:16px;}
.rail-toggle-bars span{display:block;height:2px;background:currentColor;transition:transform .22s var(--ease);}
.site-rail[data-open="true"] .rail-toggle-bars span:first-child{transform:translateY(3px) rotate(45deg);}
.site-rail[data-open="true"] .rail-toggle-bars span:last-child{transform:translateY(-3px) rotate(-45deg);}
.rail-toggle-label{display:inline-block;}
.rail-nav{display:flex;flex-direction:column;align-items:stretch;gap:2px;width:100%;}
.rail-link{
  position:relative;
  display:flex;
  align-items:center;
  justify-content:center;
  min-height:42px;
  padding:8px 6px;
  font-size:12px;
  line-height:1.35;
  letter-spacing:.06em;
  text-align:center;
  color:rgba(247,251,248,.7);
  text-decoration:none;
  transition:color .22s var(--ease),background-color .22s var(--ease);
}
.rail-link::before{
  content:"";
  position:absolute;
  left:0;top:50%;
  width:2px;height:24px;
  margin-top:-12px;
  background:var(--cyan);
  transform:scaleY(0);
  transform-origin:center;
  transition:transform .26s var(--ease);
}
.rail-link:hover{color:var(--white);background:rgba(47,243,208,.07);}
.rail-link[aria-current="page"]{color:var(--cyan);background:rgba(47,243,208,.1);}
.rail-link[aria-current="page"]::before{transform:scaleY(1);}
.rail-foot{
  margin-top:auto;
  display:flex;
  flex-direction:column;
  align-items:center;
  gap:12px;
  width:100%;
  padding-top:14px;
  border-top:1px solid var(--line-soft);
}
.version-switch{display:flex;flex-direction:column;gap:4px;width:100%;}
.version-btn{
  width:100%;
  padding:7px 2px;
  background:transparent;
  border:1px solid var(--line-soft);
  color:var(--muted);
  font-family:var(--font-body);
  font-size:11px;
  letter-spacing:.06em;
  line-height:1.4;
  cursor:pointer;
  transition:color .2s var(--ease),background-color .2s var(--ease),border-color .2s var(--ease);
}
.version-btn:hover{color:var(--white);border-color:var(--line);}
.version-btn[data-version="current"][aria-pressed="true"]{background:var(--cyan);border-color:var(--cyan);color:var(--ink);font-weight:700;}
.version-btn[data-version="archive"][aria-pressed="true"]{background:var(--orange);border-color:var(--orange);color:var(--brown);font-weight:700;}
.rail-legend{
  display:flex;
  flex-direction:column;
  gap:5px;
  width:100%;
  font-size:10px;
  line-height:1.4;
  letter-spacing:.02em;
  color:rgba(247,251,248,.55);
}
.legend-item{display:flex;align-items:center;gap:5px;}
.dot{width:6px;height:6px;flex:0 0 6px;display:inline-block;}
.dot--current{background:var(--cyan);}
.dot--archive{background:var(--orange);}

/* ============ 页脚 ============ */
.site-footer{
  position:relative;
  z-index:2;
  border-top:1px solid var(--line);
  background-color:var(--ink);
  background-image:linear-gradient(180deg,rgba(12,42,32,.92),rgba(7,26,20,1) 72%);
}
.footer-inner{
  width:100%;
  max-width:1240px;
  margin:0 auto;
  padding:56px 24px 26px;
}
.footer-grid{display:grid;grid-template-columns:1fr;gap:34px;}
.footer-brand{display:flex;flex-direction:column;align-items:flex-start;}
.footer-brand-name{
  font-family:var(--font-display);
  font-weight:800;
  font-size:clamp(1.5rem,3vw,2rem);
  line-height:1.1;
  letter-spacing:-.02em;
  color:var(--white);
}
.footer-tagline{margin-top:10px;max-width:26em;font-size:13px;line-height:1.7;color:var(--muted);}
.footer-cta{margin-top:20px;}
.footer-col{min-width:0;}
.footer-heading{
  margin-bottom:14px;
  padding-bottom:10px;
  border-bottom:1px solid var(--line-soft);
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.22em;
  color:var(--cyan-dim);
}
.footer-list{display:flex;flex-direction:column;gap:10px;}
.footer-link{
  display:inline-block;
  font-size:14px;
  color:rgba(247,251,248,.78);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.footer-link:hover{color:var(--cyan);border-bottom-color:var(--cyan);}
.footer-contact-list{gap:12px;}
.footer-contact-item{
  display:flex;
  flex-direction:column;
  gap:2px;
  font-family:var(--font-mono);
  font-size:13px;
  line-height:1.6;
  color:var(--white);
  word-break:break-word;
}
.footer-contact-label{
  font-family:var(--font-body);
  font-size:11px;
  letter-spacing:.16em;
  color:var(--orange-soft);
}
.footer-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  margin-top:44px;
  padding-top:18px;
  border-top:1px solid var(--line-soft);
}
.footer-note{
  display:flex;
  align-items:center;
  gap:8px;
  font-size:13px;
  color:var(--muted);
}
.footer-note::before{content:"";width:6px;height:6px;flex:0 0 6px;background:var(--orange);}
.footer-meta{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:12px;color:var(--muted);}
.footer-sep{color:rgba(247,251,248,.28);}

/* ============ 响应式 ============ */
@media (min-width:900px){
  body{padding-left:var(--rail);}
  .skip-link{left:calc(var(--rail) + 12px);}
  .section{padding:88px 0;}
}
@media (max-width:899px){
  body{padding-top:58px;}
  .site-rail{
    top:0;right:0;bottom:auto;left:0;
    width:auto;height:auto;
    flex-flow:row wrap;
    align-items:center;
    align-content:flex-start;
    gap:0;
    padding:10px 14px;
    border-right:0;
    border-bottom:1px solid var(--line);
    background:rgba(7,26,20,.97);
    -webkit-backdrop-filter:blur(8px);
    backdrop-filter:blur(8px);
  }
  .site-rail[data-open="true"]{
    display:grid;
    grid-template-rows:auto 1fr auto;
    height:100dvh;
    align-content:stretch;
    overflow-y:auto;
  }
  .rail-head{
    flex-direction:row;
    align-items:center;
    justify-content:space-between;
    gap:12px;
    width:100%;
  }
  .brand{flex-direction:row;align-items:center;gap:10px;}
  .brand-mark{width:34px;height:34px;font-size:16px;}
  .brand-name{writing-mode:horizontal-tb;text-orientation:initial;font-size:14px;letter-spacing:.14em;}
  .rail-toggle{display:inline-flex;}
  .rail-nav,.rail-foot{display:none;width:100%;}
  .site-rail[data-open="true"] .rail-nav{
    display:flex;
    flex-direction:column;
    gap:2px;
    margin-top:18px;
  }
  .site-rail[data-open="true"] .rail-foot{
    display:flex;
    flex-direction:row;
    flex-wrap:wrap;
    align-items:center;
    justify-content:space-between;
    gap:14px;
    margin-top:24px;
  }
  .rail-link{
    justify-content:flex-start;
    min-height:48px;
    padding:12px 14px;
    border-left:2px solid transparent;
    font-size:15px;
    text-align:left;
  }
  .rail-link::before{display:none;}
  .rail-link[aria-current="page"]{border-left-color:var(--cyan);background:rgba(47,243,208,.09);}
  .version-switch{flex-direction:row;width:auto;}
  .version-btn{width:auto;padding:8px 12px;font-size:12px;}
  .rail-legend{font-size:11px;}
  .grid-12{grid-template-columns:repeat(6,minmax(0,1fr));gap:16px;}
}
@media (max-width:640px){
  .container{padding:0 18px;}
  .footer-inner{padding:40px 18px 22px;}
  .paper{padding:20px;}
  .footer-bottom{margin-top:32px;}
  .grid-12{grid-template-columns:minmax(0,1fr);gap:16px;}
}
@media (min-width:720px){
  .footer-grid{grid-template-columns:1.5fr 1fr 1fr;gap:32px;}
}
@media (min-width:1024px){
  .footer-grid{grid-template-columns:1.7fr .9fr .9fr 1.3fr;gap:36px;}
}

/* ============ 动效降级 ============ */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  [data-reveal]{opacity:1;transform:none;}
  .btn:hover,.card:hover{transform:none;}
  .skip-link{transition:none;}
}