/* ============================================================
   /assets/site.css — 6686官方 共享外壳
   墨蓝底 + 信号橙索引 + 薄荷青链接态
   ============================================================ */

/* ---------- 0. 变量 ---------- */
:root{
  --ink:#0B1B2B;
  --panel:#13293F;
  --orange:#FF6A2B;
  --orange-soft:#FF8250;
  --mint:#7FE3C4;
  --warm:#F4F1EA;
  --mist:#E3DED2;
  --steel:#A9BCCD;
  --stone:#7B8A99;
  --clay:#C4784B;
  --moss:#6F8A62;

  --line:rgba(169,188,205,.18);
  --line-strong:rgba(169,188,205,.36);
  --mint-line:rgba(127,227,196,.45);

  --radius-card:20px;
  --radius-pill:999px;

  --wrap:1180px;
  --gutter:clamp(18px,5vw,40px);

  --ease:cubic-bezier(.2,.7,.3,1);
  --dur:200ms;

  --font-sans:"Source Han Sans SC","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,"Courier New",monospace;
}

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after{box-sizing:border-box;}

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

body,
h1,h2,h3,h4,h5,h6,
p,ul,ol,dl,dd,figure,blockquote,pre{
  margin:0;
}

ul,ol{
  padding:0;
  list-style:none;
}

button{
  font:inherit;
  color:inherit;
  background:none;
  border:0;
}

a{
  color:inherit;
  text-decoration:none;
}

svg{
  max-width:100%;
}

/* ---------- 2. 基础排版 ---------- */
body{
  background:var(--ink);
  color:var(--warm);
  font-family:var(--font-sans);
  font-size:17px;
  font-weight:400;
  line-height:1.75;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  text-rendering:optimizeLegibility;
}

h1,h2,h3,h4{
  font-weight:800;
  line-height:1.05;
  letter-spacing:-.02em;
  text-wrap:balance;
}

h1{font-size:clamp(2.4rem,6.4vw,4.4rem);}
h2{font-size:clamp(1.7rem,3.6vw,2.6rem);line-height:1.12;}
h3{font-size:clamp(1.12rem,1.9vw,1.4rem);line-height:1.32;letter-spacing:-.01em;}
h4{font-size:1rem;line-height:1.4;letter-spacing:0;}

p{text-wrap:pretty;}

::selection{
  background:var(--mint);
  color:var(--ink);
}

:where(a,button,summary,[tabindex]):focus-visible{
  outline:2px solid var(--mint);
  outline-offset:3px;
  border-radius:6px;
}

[id]{scroll-margin-top:110px;}

/* ---------- 3. 布局工具 ---------- */
.container{
  width:100%;
  max-width:var(--wrap);
  margin-inline:auto;
  padding-inline:var(--gutter);
}

.page-main{
  display:block;
  background:var(--ink);
}

.section{
  padding-block:clamp(48px,8vw,92px);
}

.section--light{
  background:var(--mist);
  color:var(--ink);
}

.section--light .lede{color:#3B4A58;}
.section--light .eyebrow{color:#B4522A;}
.section--light .rule{background:rgba(11,27,43,.14);}

.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:clamp(16px,2vw,24px);
}

.card-grid{
  display:grid;
  gap:clamp(14px,2vw,20px);
  grid-template-columns:repeat(auto-fit,minmax(240px,1fr));
}

.rule{
  height:1px;
  border:0;
  background:var(--line);
  margin-block:clamp(28px,4.5vw,52px);
}

/* ---------- 4. Skip link ---------- */
.skip-link{
  position:absolute;
  left:12px;
  top:-72px;
  z-index:300;
  display:inline-block;
  padding:10px 20px;
  border-radius:var(--radius-pill);
  background:var(--mint);
  color:var(--ink);
  font-size:.9rem;
  font-weight:700;
  transition:top var(--dur) var(--ease);
}

.skip-link:focus{
  top:12px;
}

/* ---------- 5. 头部 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:100;
  background:var(--ink);
}

.header-progress{
  position:absolute;
  top:0;
  left:0;
  right:0;
  height:2px;
  background:rgba(169,188,205,.14);
}

.header-progress-bar{
  display:block;
  width:0;
  height:100%;
  background:var(--orange);
  transition:width 120ms linear;
}

.header-upper{
  max-height:120px;
  overflow:hidden;
  background:var(--ink);
  border-bottom:1px solid var(--line);
  transition:max-height var(--dur) var(--ease),
             opacity var(--dur) var(--ease),
             transform var(--dur) var(--ease);
}

.header-upper-inner{
  display:flex;
  align-items:center;
  gap:18px;
  min-height:58px;
  padding-block:10px;
}

.site-header[data-compact] .header-upper{
  max-height:0;
  opacity:0;
  transform:translateY(-10px);
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-weight:800;
  letter-spacing:-.01em;
  white-space:nowrap;
}

.brand-mark{
  width:14px;
  height:14px;
  border-radius:4px;
  background:var(--orange);
  box-shadow:0 0 0 3px rgba(255,106,43,.16);
  flex:none;
}

.brand-name{
  font-size:1.05rem;
  line-height:1.2;
}

.header-tagline{
  font-family:var(--font-mono);
  font-size:.8rem;
  letter-spacing:.08em;
  color:var(--steel);
  line-height:1.4;
}

.ghost-pill{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:8px 16px;
  border:1px solid var(--line-strong);
  border-radius:var(--radius-pill);
  background:transparent;
  color:var(--warm);
  font-size:.84rem;
  font-weight:500;
  line-height:1.4;
  white-space:nowrap;
  transition:border-color var(--dur) var(--ease),
             color var(--dur) var(--ease),
             background var(--dur) var(--ease);
}

.ghost-pill:hover{
  border-color:var(--mint);
  color:var(--mint);
  background:rgba(127,227,196,.08);
}

.ghost-pill-dot{
  width:7px;
  height:7px;
  border-radius:50%;
  background:var(--mint);
  flex:none;
}

.header-utility{
  margin-inline-start:auto;
}

.header-lower{
  background:var(--panel);
  border-bottom:1px solid var(--line);
}

.header-lower-inner{
  display:flex;
  align-items:center;
  gap:12px;
  min-height:56px;
}

.primary-nav{
  display:block;
}

.nav-list{
  display:flex;
  align-items:center;
  flex-wrap:wrap;
  gap:4px;
}

.nav-item{
  display:block;
}

.nav-link{
  display:inline-block;
  padding:8px 15px;
  border-radius:var(--radius-pill);
  color:var(--steel);
  font-size:.92rem;
  font-weight:500;
  line-height:1.4;
  white-space:nowrap;
  transition:background var(--dur) var(--ease),
             color var(--dur) var(--ease);
}

.nav-link:hover{
  color:var(--warm);
  background:rgba(244,241,234,.08);
}

.nav-link[aria-current="page"]{
  background:var(--orange);
  color:var(--ink);
  font-weight:700;
}

.nav-link[aria-current="page"]:hover{
  background:var(--orange-soft);
  color:var(--ink);
}

.nav-toggle{
  display:none;
  align-items:center;
  gap:10px;
  padding:8px 14px;
  border:1px solid var(--line-strong);
  border-radius:var(--radius-pill);
  color:var(--warm);
  cursor:pointer;
  transition:border-color var(--dur) var(--ease),
             color var(--dur) var(--ease);
}

.nav-toggle:hover{
  border-color:var(--mint);
  color:var(--mint);
}

.nav-toggle-bars{
  display:inline-flex;
  flex-direction:column;
  gap:4px;
  width:16px;
  flex:none;
}

.nav-toggle-bars span{
  display:block;
  height:2px;
  border-radius:2px;
  background:currentColor;
  transition:transform var(--dur) var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:first-child{
  transform:translateY(3px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars span:last-child{
  transform:translateY(-3px) rotate(-45deg);
}

.nav-toggle-text{
  font-size:.82rem;
  font-weight:500;
  letter-spacing:.06em;
  line-height:1;
}

.header-code{
  margin-inline-start:auto;
  font-family:var(--font-mono);
  font-size:.72rem;
  letter-spacing:.18em;
  color:var(--stone);
  white-space:nowrap;
}

/* ---------- 6. 页脚 ---------- */
.site-footer{
  position:relative;
  overflow:hidden;
  background:var(--ink);
  border-top:1px solid var(--line);
  padding-block:clamp(44px,7vw,76px) 28px;
  color:var(--warm);
}

.footer-mesh{
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(rgba(169,188,205,.07) 1px,transparent 1px),
    linear-gradient(90deg,rgba(169,188,205,.07) 1px,transparent 1px);
  background-size:48px 48px;
  opacity:.55;
}

.site-footer .container{
  position:relative;
  z-index:1;
}

.footer-grid{
  display:grid;
  grid-template-columns:1.7fr repeat(3,1fr);
  gap:clamp(24px,4vw,48px);
  align-items:start;
}

.brand--footer{
  color:var(--warm);
  font-size:1.02rem;
}

.footer-claim{
  margin-top:16px;
  max-width:30ch;
  color:var(--steel);
  font-size:.94rem;
  line-height:1.7;
}

.footer-addr{
  margin-top:14px;
  color:var(--steel);
}

.mono{
  font-family:var(--font-mono);
  font-size:.8em;
  letter-spacing:.06em;
  color:var(--steel);
}

.footer-title{
  position:relative;
  margin-bottom:16px;
  padding-inline-start:14px;
  font-family:var(--font-mono);
  font-size:.78rem;
  font-weight:500;
  letter-spacing:.18em;
  line-height:1.4;
  color:var(--mint);
}

.footer-title::before{
  content:"";
  position:absolute;
  left:0;
  top:.42em;
  width:6px;
  height:6px;
  border-radius:2px;
  background:var(--orange);
}

.footer-list{
  display:grid;
  gap:9px;
  counter-reset:fl;
}

.footer-list li{
  display:flex;
  align-items:baseline;
  gap:10px;
  font-size:.92rem;
  line-height:1.55;
  color:var(--steel);
}

.footer-list li::before{
  counter-increment:fl;
  content:counter(fl,decimal-leading-zero);
  flex:none;
  font-family:var(--font-mono);
  font-size:.68rem;
  letter-spacing:.08em;
  color:var(--stone);
}

.footer-list a{
  color:var(--steel);
  transition:color var(--dur) var(--ease);
}

.footer-list a:hover,
.footer-list a:focus-visible{
  color:var(--mint);
}

.footer-list--plain{
  counter-reset:none;
}

.footer-list--plain li::before{
  content:none;
}

.footer-list--plain .mono{
  color:var(--clay);
  flex:none;
  min-width:2.6em;
}

.footer-note{
  margin-top:clamp(28px,4vw,44px);
  padding-top:20px;
  border-top:1px solid var(--line);
  font-size:.88rem;
  color:var(--steel);
}

.footer-legal{
  margin-top:14px;
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:8px 24px;
}

.footer-copy{
  font-size:.8rem;
  color:var(--steel);
}

.footer-icp{
  font-size:.76rem;
  color:var(--stone);
}

/* ---------- 7. 通用按钮 / 标签 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.5em;
  padding:.78em 1.5em;
  border:1px solid transparent;
  border-radius:var(--radius-pill);
  font-family:var(--font-sans);
  font-size:.95rem;
  font-weight:700;
  line-height:1.2;
  text-align:center;
  cursor:pointer;
  transition:background var(--dur) var(--ease),
             color var(--dur) var(--ease),
             border-color var(--dur) var(--ease),
             transform var(--dur) var(--ease);
}

.btn-primary{
  background:var(--orange);
  color:var(--ink);
}

.btn-primary:hover{
  background:var(--orange-soft);
}

.btn-ghost{
  background:transparent;
  border-color:var(--line-strong);
  color:var(--warm);
}

.btn-ghost:hover{
  border-color:var(--mint);
  color:var(--mint);
}

.btn-quiet{
  background:rgba(127,227,196,.12);
  color:var(--mint);
}

.btn-quiet:hover{
  background:rgba(127,227,196,.2);
}

.pill{
  display:inline-flex;
  align-items:center;
  gap:.45em;
  padding:.32em .85em;
  border:1px solid var(--line-strong);
  border-radius:var(--radius-pill);
  font-family:var(--font-mono);
  font-size:.72rem;
  font-weight:500;
  letter-spacing:.1em;
  line-height:1.6;
  color:var(--steel);
}

.pill-orange{
  border-color:transparent;
  background:var(--orange);
  color:var(--ink);
  font-weight:700;
}

.pill-mint{
  border-color:var(--mint-line);
  background:rgba(127,227,196,.1);
  color:var(--mint);
}

/* ---------- 8. 面包屑 ---------- */
.crumbs{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  font-family:var(--font-mono);
  font-size:.74rem;
  letter-spacing:.08em;
  line-height:1.6;
  color:var(--stone);
}

.crumbs li{
  display:inline-flex;
  align-items:center;
}

.crumbs li + li::before{
  content:"/";
  margin-inline-end:8px;
  color:rgba(169,188,205,.4);
}

.crumbs a{
  color:var(--steel);
  transition:color var(--dur) var(--ease);
}

.crumbs a:hover{
  color:var(--mint);
}

/* ---------- 9. 正文块 ---------- */
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:.6em;
  font-family:var(--font-mono);
  font-size:.76rem;
  letter-spacing:.16em;
  line-height:1.6;
  color:var(--orange);
}

.eyebrow::before{
  content:"";
  width:7px;
  height:7px;
  border-radius:2px;
  background:currentColor;
  flex:none;
}

.lede{
  max-width:34em;
  font-size:clamp(1.04rem,1.6vw,1.2rem);
  line-height:1.75;
  color:var(--steel);
}

.prose{
  max-width:36em;
  font-size:1rem;
  line-height:1.78;
  color:var(--steel);
}

.prose p + p{
  margin-top:1em;
}

.prose h2,
.prose h3{
  margin-top:1.8em;
  margin-bottom:.6em;
  color:var(--warm);
}

.prose ul{
  margin-top:.8em;
  padding:0;
  list-style:none;
}

.prose ul li{
  position:relative;
  margin-top:.55em;
  padding-inline-start:1.4em;
}

.prose ul li::before{
  content:"";
  position:absolute;
  left:0;
  top:.72em;
  width:6px;
  height:6px;
  border-radius:2px;
  background:var(--orange);
}

.prose a{
  color:var(--mint);
  border-bottom:1px solid var(--mint-line);
}

/* ---------- 10. 索引卡 ---------- */
.idx-card{
  position:relative;
  display:flex;
  flex-direction:column;
  gap:12px;
  padding:clamp(18px,2.2vw,26px);
  border:1px solid var(--line);
  border-radius:var(--radius-card);
  background:var(--panel);
  transition:transform var(--dur) var(--ease),
             border-color var(--dur) var(--ease);
}

.idx-card:hover,
.idx-card:focus-within{
  transform:translateY(-2px);
  border-color:var(--mint-line);
}

.idx-card h3{
  color:var(--warm);
}

.idx-card p{
  color:var(--steel);
  font-size:.94rem;
  line-height:1.7;
}

.idx-num{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  align-self:flex-start;
  min-width:2.4em;
  padding:.18em .55em;
  border-radius:7px;
  background:var(--orange);
  color:var(--ink);
  font-family:var(--font-mono);
  font-size:.78rem;
  font-weight:700;
  letter-spacing:.08em;
  line-height:1.6;
  transition:transform var(--dur) var(--ease);
}

.idx-card:hover .idx-num{
  transform:translateY(-2px);
}

/* ---------- 11. 三步指引条 ---------- */
.step-strip{
  display:flex;
  gap:16px;
  overflow-x:auto;
  scroll-snap-type:x mandatory;
  padding-bottom:12px;
  -webkit-overflow-scrolling:touch;
}

.step{
  flex:0 0 min(78%,320px);
  scroll-snap-align:start;
  padding:clamp(18px,2.2vw,26px);
  border:1px solid var(--line);
  border-radius:var(--radius-card);
  background:var(--panel);
}

.step h3{
  margin-top:12px;
  color:var(--warm);
}

.step p{
  margin-top:8px;
  font-size:.94rem;
  line-height:1.7;
  color:var(--steel);
}

/* ---------- 12. 对照表 ---------- */
.table-wrap{
  width:100%;
  overflow-x:auto;
  border:1px solid var(--line);
  border-radius:var(--radius-card);
  background:var(--panel);
}

.cmp-table{
  width:100%;
  min-width:520px;
  border-collapse:collapse;
  font-size:.92rem;
}

.cmp-table th,
.cmp-table td{
  padding:14px 18px;
  text-align:left;
  vertical-align:top;
  border-bottom:1px solid var(--line);
}

.cmp-table thead th{
  font-family:var(--font-mono);
  font-size:.72rem;
  font-weight:500;
  letter-spacing:.12em;
  color:var(--steel);
  border-bottom-color:var(--line-strong);
  white-space:nowrap;
}

.cmp-table tbody tr:last-child td{
  border-bottom:0;
}

.cmp-table tbody tr:hover td{
  background:rgba(169,188,205,.06);
}

.cmp-table tbody tr.is-key td{
  background:rgba(127,227,196,.09);
  color:var(--warm);
}

/* ---------- 13. 折叠问答 ---------- */
.fold{
  border:1px solid var(--line);
  border-radius:16px;
  background:var(--panel);
  overflow:hidden;
}

.fold + .fold{
  margin-top:10px;
}

.fold summary{
  display:flex;
  align-items:center;
  gap:12px;
  padding:16px 20px;
  font-size:1rem;
  font-weight:700;
  line-height:1.5;
  color:var(--warm);
  cursor:pointer;
  list-style:none;
}

.fold summary::-webkit-details-marker{
  display:none;
}

.fold summary::after{
  content:"+";
  margin-inline-start:auto;
  font-family:var(--font-mono);
  font-size:1.1rem;
  line-height:1;
  color:var(--orange);
  flex:none;
}

.fold[open] summary::after{
  content:"–";
}

.fold-body{
  padding:0 20px 18px;
  font-size:.95rem;
  line-height:1.75;
  color:var(--steel);
}

/* ---------- 14. 锚点目录 ---------- */
.toc{
  position:sticky;
  top:96px;
}

.toc-title{
  margin-bottom:12px;
  font-family:var(--font-mono);
  font-size:.74rem;
  font-weight:500;
  letter-spacing:.18em;
  color:var(--stone);
}

.toc-list{
  display:grid;
  gap:2px;
}

.toc-link{
  display:block;
  padding:8px 12px 8px 14px;
  border-inline-start:2px solid transparent;
  border-radius:0 10px 10px 0;
  font-size:.88rem;
  line-height:1.5;
  color:var(--stone);
  transition:color var(--dur) var(--ease),
             border-color var(--dur) var(--ease),
             background var(--dur) var(--ease);
}

.toc-link:hover{
  color:var(--warm);
  background:rgba(169,188,205,.07);
}

.toc-link.is-active{
  color:var(--orange);
  border-inline-start-color:var(--orange);
  background:rgba(255,106,43,.08);
}

/* ---------- 15. 图片容器基础规则 ---------- */
.img-frame{
  position:relative;
  width:100%;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:var(--radius-card);
  background:var(--panel);
  aspect-ratio:16 / 10;
}

.img-frame > img,
.img-frame > svg,
.img-frame > picture,
.img-frame > picture > img{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
}

.img-frame--wide{aspect-ratio:21 / 9;}
.img-frame--square{aspect-ratio:1 / 1;}
.img-frame--tall{aspect-ratio:4 / 5;}

/* ---------- 16. 平板 ---------- */
@media (max-width:960px){
  .footer-grid{
    grid-template-columns:repeat(2,minmax(0,1fr));
  }

  .footer-brand{
    grid-column:1 / -1;
  }

  .grid-12{
    grid-template-columns:repeat(6,minmax(0,1fr));
  }

  .toc{
    position:static;
  }
}

/* ---------- 17. 手机 ---------- */
@media (max-width:880px){
  body{
    font-size:16px;
  }

  .header-upper-inner{
    gap:12px;
    min-height:54px;
  }

  .header-tagline,
  .header-code{
    display:none;
  }

  .nav-toggle{
    display:inline-flex;
  }

  .header-lower-inner{
    justify-content:flex-start;
    gap:10px;
  }

  .primary-nav{
    position:absolute;
    top:100%;
    left:0;
    right:0;
    display:none;
    padding:14px var(--gutter) 18px;
    background:var(--panel);
    border-bottom:1px solid var(--line-strong);
  }

  .primary-nav[data-open]{
    display:block;
  }

  .nav-list{
    flex-direction:column;
    align-items:stretch;
    gap:2px;
  }

  .nav-link{
    display:block;
    padding:12px 14px;
    border-radius:14px;
    font-size:1rem;
  }

  .nav-link[aria-current="page"]{
    border-radius:14px;
  }
}

@media (max-width:560px){
  .grid-12{
    grid-template-columns:repeat(2,minmax(0,1fr));
  }

  .footer-grid{
    grid-template-columns:1fr;
  }

  .ghost-pill{
    padding:7px 13px;
    font-size:.8rem;
  }

  .brand-name{
    font-size:1rem;
  }

  .footer-legal{
    flex-direction:column;
    align-items:flex-start;
  }
}

/* ---------- 18. 减少动态 ---------- */
@media (prefers-reduced-motion:reduce){
  *,
  *::before,
  *::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }

  .idx-card:hover,
  .idx-card:focus-within{
    transform:none;
  }

  .idx-card:hover .idx-num{
    transform:none;
  }

  .site-header[data-compact] .header-upper{
    transform:none;
  }

  .step-strip{
    scroll-snap-type:none;
  }
}