*,*::before,*::after{box-sizing:border-box}

:root{
  --ink-900:#081826;
  --ink-800:#0B2135;
  --ink-700:#0F2C47;
  --cream:#F7F0E3;
  --cream-2:#EDE3D2;
  --card:#FFFDF7;
  --amber:#D48A2C;
  --amber-soft:#EDC27A;
  --jade:#5E8E7E;
  --jade-soft:#DCE9E2;
  --rust:#B45335;
  --char:#33322D;
  --ink-soft:#5D584F;
  --line:#C9BBA7;
  --line-soft:rgba(201,187,167,.42);
  --rail-w:96px;
  --topbar-h:60px;
  --maxw:1280px;
  --shadow:0 10px 30px rgba(8,24,38,.08);
  --ease:cubic-bezier(.2,.7,.3,1);
  --font-head:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
}

html{-webkit-text-size-adjust:100%;text-size-adjust:100%}

body{
  margin:0;
  padding-left:var(--rail-w);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.8;
  color:var(--char);
  background-color:var(--cream);
  background-image:linear-gradient(180deg,rgba(212,138,44,.07),rgba(212,138,44,0) 340px);
  background-repeat:no-repeat;
  -webkit-font-smoothing:antialiased;
  overflow-wrap:break-word;
}

h1,h2,h3,h4{
  font-family:var(--font-head);
  color:var(--ink-900);
  letter-spacing:-.02em;
  line-height:1.25;
  margin:0 0 .5em;
  font-weight:800;
}
h1{font-size:clamp(34px,5.2vw,64px);font-weight:900}
h2{font-size:clamp(24px,3.4vw,36px)}
h3{font-size:clamp(18px,2.2vw,22px)}
p{margin:0 0 1em}
ul,ol{margin:0;padding:0;list-style:none}
img,svg,picture{display:block;max-width:100%}
button{font:inherit;color:inherit}
a{color:inherit}

:focus-visible{outline:3px solid var(--amber);outline-offset:3px;border-radius:1px}
.rail :focus-visible,.topbar :focus-visible,.site-footer :focus-visible{outline-color:var(--amber-soft)}
#main-content{scroll-margin-top:calc(var(--topbar-h) + 16px)}

/* ---------- 通用排版与容器 ---------- */
.shell{width:100%;max-width:var(--maxw);margin-inline:auto;padding-inline:clamp(20px,4vw,56px)}
.prose{max-width:70ch}
.prose p{max-width:68ch;margin-bottom:1.1em}
.prose h2,.prose h3{margin-top:1.6em}
.lead{font-size:clamp(16px,1.6vw,19px);line-height:1.85;color:var(--ink-soft);max-width:64ch}
.num{font-variant-numeric:tabular-nums;font-weight:700}
.muted{color:var(--ink-soft)}

/* ---------- 跳过链接 ---------- */
.skip-link{
  position:fixed;top:12px;left:12px;z-index:200;
  transform:translateY(-180%);
  display:inline-block;padding:10px 18px;
  background:var(--amber);color:var(--ink-900);
  font-size:14px;font-weight:800;letter-spacing:.04em;
  text-decoration:none;border-radius:2px;
  transition:transform .22s var(--ease);
}
.skip-link:focus,.skip-link:focus-visible{transform:translateY(0)}

/* ---------- 头部外壳 ---------- */
.site-header{position:relative;z-index:60}

/* 书脊轨道（桌面） */
.rail{
  position:fixed;top:0;bottom:0;left:0;z-index:75;
  width:var(--rail-w);
  display:flex;flex-direction:column;align-items:center;gap:16px;
  padding:22px 0 18px;
  background:var(--ink-900);
  border-right:1px solid rgba(237,194,122,.18);
  color:var(--cream);
  overflow-y:auto;overscroll-behavior:contain;
}
.rail::-webkit-scrollbar{width:0;height:0}

.rail__brand{
  display:flex;align-items:flex-start;gap:9px;
  padding:0 8px 16px;
  text-decoration:none;color:var(--cream);
  border-bottom:1px solid rgba(201,187,167,.2);
  transition:color .2s var(--ease);
}
.rail__brand-mark{
  writing-mode:vertical-rl;
  font-family:var(--font-head);
  font-size:19px;font-weight:900;letter-spacing:.14em;line-height:1.15;
}
.rail__brand-sub{
  writing-mode:vertical-rl;
  font-size:8.5px;letter-spacing:.2em;line-height:1.4;
  color:var(--amber-soft);opacity:.82;
}
.rail__brand:hover .rail__brand-mark{color:var(--amber-soft)}

.rail__nav{width:100%;display:flex;justify-content:center}
.rail__list{width:100%;display:flex;flex-direction:column;margin:0;padding:0}
.rail__item{width:100%}

.rail__link{
  position:relative;
  display:flex;flex-direction:column;align-items:center;gap:6px;
  width:100%;padding:9px 0;
  text-decoration:none;
  color:rgba(247,240,227,.6);
  transition:color .2s var(--ease),background-color .2s var(--ease);
}
.rail__link::before{
  content:"";position:absolute;top:8px;bottom:8px;left:0;width:3px;
  background:var(--amber);
  transform:scaleX(0);transform-origin:left center;
  transition:transform .26s var(--ease);
}
.rail__num{
  font-size:9px;font-weight:700;letter-spacing:.1em;
  font-variant-numeric:tabular-nums;
  color:var(--amber);
  transition:transform .2s var(--ease);
}
.rail__label{
  writing-mode:vertical-rl;
  font-size:13px;font-weight:700;letter-spacing:.12em;line-height:1.2;
}
.rail__link:hover{color:var(--cream);background:rgba(237,194,122,.06)}
.rail__link:hover .rail__num{transform:translateY(-2px)}
.rail__link[aria-current="page"]{
  color:var(--cream);
  background:rgba(237,194,122,.08);
}
.rail__link[aria-current="page"]::before{transform:scaleX(1)}
.rail__link[aria-current="page"] .rail__num{color:var(--amber-soft);transform:translateY(-2px)}

.rail__cta{
  margin-top:auto;
  writing-mode:vertical-rl;
  display:inline-block;
  padding:14px 9px;
  background:var(--amber);color:var(--ink-900);
  font-size:12px;font-weight:800;letter-spacing:.2em;line-height:1;
  text-decoration:none;border-radius:2px;
  transition:background-color .2s var(--ease),color .2s var(--ease);
}
.rail__cta:hover{background:var(--amber-soft);color:var(--ink-900)}

/* 顶部品牌条（移动） */
.topbar{
  display:none;
  position:fixed;top:0;left:0;right:0;z-index:80;
  height:var(--topbar-h);
  align-items:center;gap:12px;
  padding:0 16px;
  background:var(--ink-900);
  border-bottom:1px solid rgba(237,194,122,.22);
  color:var(--cream);
}
.topbar__brand{
  font-family:var(--font-head);
  font-size:17px;font-weight:900;letter-spacing:.06em;
  color:var(--cream);text-decoration:none;white-space:nowrap;
}
.topbar__divider{width:1px;height:16px;background:rgba(247,240,227,.28);flex:none}
.topbar__descriptor{
  font-size:11px;letter-spacing:.06em;
  color:rgba(247,240,227,.6);
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;
}

.nav-toggle{
  margin-left:auto;flex:none;
  display:inline-flex;align-items:center;gap:8px;
  padding:7px 12px;
  background:transparent;color:var(--cream);
  border:1px solid rgba(237,194,122,.45);border-radius:2px;
  font-size:12px;letter-spacing:.08em;cursor:pointer;
  transition:background-color .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.nav-toggle:hover{background:var(--amber);color:var(--ink-900);border-color:var(--amber)}
.nav-toggle__bars{display:inline-flex;flex-direction:column;gap:3px;width:14px}
.nav-toggle__bars i{display:block;height:2px;background:currentColor;transition:transform .26s var(--ease),opacity .2s var(--ease)}
.site-header[data-open] .nav-toggle__bars i:nth-child(1){transform:translateY(5px) rotate(45deg)}
.site-header[data-open] .nav-toggle__bars i:nth-child(2){opacity:0}
.site-header[data-open] .nav-toggle__bars i:nth-child(3){transform:translateY(-5px) rotate(-45deg)}

.nav-scrim{display:none}

/* 滚动进度 */
.scroll-progress{
  position:fixed;z-index:95;pointer-events:none;
  left:calc(var(--rail-w) - 3px);top:0;bottom:0;width:3px;
  background:rgba(201,187,167,.22);
}
.scroll-progress__bar{
  display:block;width:100%;height:100%;
  background:var(--amber);
  transform:scaleY(var(--p,0));transform-origin:top center;
}

/* ---------- 页脚 ---------- */
.site-footer{
  margin-top:clamp(56px,8vw,110px);
  background:var(--ink-900);
  color:rgba(247,240,227,.76);
  font-size:14px;
}
.footer__notice{
  display:flex;align-items:center;gap:10px;
  padding:12px clamp(20px,4vw,56px);
  background:var(--jade-soft);
  color:var(--ink-700);
  font-size:12.5px;letter-spacing:.03em;
  border-bottom:1px solid var(--line);
}
.footer__notice-dot{
  width:7px;height:7px;border-radius:50%;flex:none;
  background:var(--jade);
  box-shadow:0 0 0 4px rgba(94,142,126,.18);
}
.footer__inner{padding-block:clamp(34px,4.5vw,58px) 0}

.footer__top{
  display:grid;gap:clamp(28px,4vw,56px);
  grid-template-columns:minmax(200px,.9fr) minmax(0,2.6fr);
  padding-bottom:clamp(26px,3.5vw,44px);
  border-bottom:1px solid rgba(201,187,167,.22);
}
.footer__mark{
  position:relative;
  display:inline-block;
  font-family:var(--font-head);
  font-size:clamp(22px,2.4vw,28px);font-weight:900;letter-spacing:.1em;
  color:var(--cream);text-decoration:none;
  padding-bottom:8px;
}
.footer__mark::after{
  content:"";position:absolute;left:0;bottom:0;
  width:38px;height:3px;background:var(--amber);
  transition:width .26s var(--ease);
}
.footer__mark:hover::after{width:100%}
.footer__descriptor{margin:12px 0 0;font-size:12px;letter-spacing:.12em;color:var(--amber-soft)}
.footer__meta{margin:14px 0 0;max-width:24ch;font-size:12px;line-height:1.9;color:rgba(247,240,227,.55)}

.footer__columns{display:grid;gap:clamp(22px,3vw,36px);grid-template-columns:repeat(4,minmax(0,1fr))}
.footer__col-title{
  margin:0 0 14px;padding-bottom:10px;
  font-size:12px;font-weight:700;letter-spacing:.16em;
  color:var(--amber);
  border-bottom:1px solid rgba(201,187,167,.24);
}
.footer__list{display:flex;flex-direction:column;gap:9px}
.footer__link{
  position:relative;display:inline-block;
  font-size:14px;line-height:1.6;
  color:rgba(247,240,227,.8);text-decoration:none;
  transition:color .2s var(--ease);
}
.footer__link::after{
  content:"";position:absolute;left:0;bottom:-2px;width:100%;height:1px;
  background:var(--amber);
  transform:scaleX(0);transform-origin:left center;
  transition:transform .26s var(--ease);
}
.footer__link:hover{color:var(--cream)}
.footer__link:hover::after{transform:scaleX(1)}
.footer__text{margin:0;font-size:13.5px;line-height:1.85;color:rgba(247,240,227,.64)}

.footer__legal{
  display:flex;flex-wrap:wrap;align-items:center;gap:10px 24px;
  padding-block:20px 26px;
  font-size:12px;letter-spacing:.04em;
  color:rgba(247,240,227,.55);
}
.footer__legal-nav{display:flex;flex-wrap:wrap;align-items:center;gap:8px 20px}
.footer__legal-link{
  color:rgba(247,240,227,.74);text-decoration:none;
  border-bottom:1px solid rgba(201,187,167,.38);padding-bottom:1px;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.footer__legal-link:hover{color:var(--amber-soft);border-color:var(--amber-soft)}
.footer__icp{margin:0 0 0 auto;font-variant-numeric:tabular-nums;font-size:12px}

/* ---------- 基础组件 ---------- */
.breadcrumb{padding-top:clamp(14px,2vw,22px);font-size:12px;letter-spacing:.06em;color:var(--ink-soft)}
.breadcrumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:6px}
.breadcrumb__item{display:inline-flex;align-items:center;gap:6px}
.breadcrumb__link{
  color:var(--ink-soft);text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.breadcrumb__link:hover{color:var(--amber);border-bottom-color:var(--amber)}
.breadcrumb__sep{color:var(--line)}

.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:11px 20px;border-radius:2px;
  border:1px solid transparent;
  font-size:14px;font-weight:700;letter-spacing:.04em;
  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--primary{background:var(--amber);color:var(--ink-900);border-color:var(--amber)}
.btn--primary:hover{background:var(--ink-900);color:var(--cream);border-color:var(--ink-900)}
.btn--ghost{background:transparent;color:var(--ink-900);border-color:var(--line)}
.btn--ghost:hover{background:var(--amber-soft);border-color:var(--amber);color:var(--ink-900)}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:3px 9px;border-radius:2px;
  font-size:11.5px;font-weight:700;letter-spacing:.08em;line-height:1.6;
  background:var(--card);color:var(--char);
  border:1px solid var(--line);
}
.tag--jade{background:var(--jade-soft);border-color:rgba(94,142,126,.42);color:#26483C}
.tag--amber{background:rgba(237,194,122,.38);border-color:rgba(212,138,44,.5);color:var(--ink-700)}
.tag--rust{background:rgba(180,83,53,.1);border-color:rgba(180,83,53,.45);color:#7D3924}

.panel{
  background:var(--card);
  border:1px solid var(--line);
  border-radius:3px;
  padding:clamp(18px,2.4vw,28px);
  box-shadow:var(--shadow);
}
.panel--dark{background:var(--ink-700);border-color:rgba(237,194,122,.28);color:rgba(247,240,227,.82)}
.panel--dark .panel__title,.panel--dark h2,.panel--dark h3{color:var(--cream)}
.panel__title{margin:0 0 10px;font-size:16px;font-weight:800;letter-spacing:.02em;color:var(--ink-900)}

.section-head{
  display:grid;grid-template-columns:auto minmax(0,1fr);
  gap:6px 16px;align-items:baseline;
  padding-top:18px;border-top:1px solid var(--line);
  margin-bottom:clamp(20px,3vw,36px);
}
.section-head__num{
  font-size:12px;font-weight:800;letter-spacing:.16em;
  color:var(--amber);font-variant-numeric:tabular-nums;
}
.section-head__title{margin:0;font-size:clamp(22px,3vw,32px);line-height:1.3;letter-spacing:-.02em}
.section-head__note{grid-column:1 / -1;margin:4px 0 0;font-size:13px;line-height:1.85;color:var(--ink-soft);max-width:62ch}

.grid{display:grid;gap:clamp(16px,2.4vw,28px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}

.media{
  position:relative;display:block;width:100%;
  aspect-ratio:16 / 10;
  overflow:hidden;border:1px solid var(--line);border-radius:3px;
  background-color:var(--cream-2);
  background-image:
    linear-gradient(135deg,rgba(212,138,44,.16),rgba(212,138,44,0) 62%),
    repeating-linear-gradient(90deg,rgba(201,187,167,.42) 0 1px,transparent 1px 26px),
    repeating-linear-gradient(0deg,rgba(201,187,167,.3) 0 1px,transparent 1px 26px);
}
.media--wide{aspect-ratio:21 / 9}
.media--square{aspect-ratio:1 / 1}
.media--tall{aspect-ratio:4 / 5}
.media > img,.media > picture,.media > svg,.media > video{
  position:absolute;inset:0;width:100%;height:100%;object-fit:cover;
}
.media__caption{margin:8px 0 0;font-size:12px;line-height:1.9;letter-spacing:.04em;color:var(--ink-soft)}

.toc{border-left:2px solid var(--line);padding-left:0}
.toc__list{display:flex;flex-direction:column;gap:1px}
.toc__link{
  display:block;
  margin-left:-2px;padding:6px 10px 6px 16px;
  border-left:2px solid transparent;
  font-size:13.5px;color:var(--ink-soft);text-decoration:none;
  transition:color .2s var(--ease),background-color .2s var(--ease),border-color .2s var(--ease);
}
.toc__link:hover{color:var(--ink-900);background:rgba(237,194,122,.2)}
.toc__link.is-active{
  color:var(--ink-900);font-weight:700;
  border-left-color:var(--amber);
  background:rgba(237,194,122,.24);
}

.table{
  width:100%;border-collapse:collapse;
  font-size:15px;line-height:1.7;
  background:var(--card);
  border:1px solid var(--line);
}
.table thead th{
  position:sticky;top:0;z-index:2;
  padding:12px 14px;
  background:var(--ink-700);color:var(--cream);
  text-align:left;font-size:13px;font-weight:700;letter-spacing:.08em;
  border-bottom:1px solid var(--ink-900);
}
.table td{padding:12px 14px;border-bottom:1px solid var(--line-soft);vertical-align:top}
.table tbody tr:nth-child(even){background:var(--cream-2)}
.table tbody tr{transition:background-color .18s var(--ease)}
.table tbody tr:hover{background:var(--amber-soft)}

/* ---------- 响应式 ---------- */
@media (min-width:1024px) and (max-width:1319px){
  :root{--rail-w:88px}
}

@media (max-width:1023.98px){
  body{padding-left:0;padding-top:var(--topbar-h)}
  .topbar{display:flex}

  .rail{
    top:var(--topbar-h);right:0;bottom:0;left:auto;
    width:min(88vw,360px);
    align-items:stretch;gap:14px;
    padding:18px 0 22px;
    border-right:0;
    border-left:1px solid rgba(237,194,122,.24);
    box-shadow:-18px 0 44px rgba(8,24,38,.3);
    transform:translateX(103%);
    transition:transform .32s var(--ease);
    z-index:74;
  }
  .site-header[data-open] .rail{transform:none}

  .rail__brand{
    flex-direction:row;align-items:baseline;gap:10px;
    padding:0 22px 16px;border-bottom:1px solid rgba(201,187,167,.22);
  }
  .rail__brand-mark{writing-mode:horizontal-tb;font-size:20px;letter-spacing:.08em}
  .rail__brand-sub{
    writing-mode:horizontal-tb;
    font-size:10.5px;letter-spacing:.08em;
    margin-left:auto;text-align:right;
  }

  .rail__nav{width:100%;display:block}
  .rail__link{
    flex-direction:row;align-items:center;justify-content:flex-start;
    gap:14px;padding:14px 22px;
    color:rgba(247,240,227,.8);
  }
  .rail__link::before{top:10px;bottom:10px;width:3px}
  .rail__num{font-size:11px;letter-spacing:.14em}
  .rail__label{writing-mode:horizontal-tb;font-size:15px;letter-spacing:.04em}

  .rail__cta{
    writing-mode:horizontal-tb;
    margin:18px 22px 0;
    padding:13px 18px;
    text-align:center;letter-spacing:.14em;font-size:13px;
  }

  .nav-scrim{
    display:block;
    position:fixed;top:var(--topbar-h);right:0;bottom:0;left:0;z-index:70;
    border:0;padding:0;cursor:pointer;
    background:rgba(8,24,38,.55);
    opacity:0;pointer-events:none;
    transition:opacity .3s var(--ease);
  }
  .site-header[data-open] .nav-scrim{opacity:1;pointer-events:auto}

  .scroll-progress{
    top:var(--topbar-h);left:0;right:0;bottom:auto;
    width:auto;height:3px;
  }
  .scroll-progress__bar{transform:scaleX(var(--p,0));transform-origin:left center}

  .footer__top{grid-template-columns:minmax(0,1fr)}
  .footer__columns{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer__meta{max-width:40ch}
  .footer__icp{margin-left:0}
  .table thead th{top:var(--topbar-h)}
}

@media (max-width:860px){
  .grid--2,.grid--3{grid-template-columns:minmax(0,1fr)}
  .section-head{grid-template-columns:minmax(0,1fr)}
  .section-head__num{padding-bottom:2px}
}

@media (max-width:560px){
  .topbar__descriptor{display:none}
  .footer__columns{grid-template-columns:minmax(0,1fr)}
  .footer__notice{font-size:11.5px}
  .table{font-size:14px}
  .table thead th,.table td{padding:10px 11px}
}

.has-drawer-open,
.has-drawer-open body{overflow:hidden}

@media (prefers-reduced-motion: no-preference){
  html{scroll-behavior:smooth}
}

@media (prefers-reduced-motion: reduce){
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .rail{transition:none}
}