:root{
  --bg:#f5f7fb;
  --panel:#ffffff;
  --soft:#f8fafc;
  --text:#172033;
  --muted:#667085;
  --line:#dce3ee;
  --brand:#1f6feb;
  --brand-dark:#164ea6;
  --teal:#0f766e;
  --amber:#b45309;
  --green:#047857;
  --shadow:0 14px 34px rgba(20,31,54,.10);
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  background:linear-gradient(180deg,#f7f9fd 0,#f5f7fb 280px);
  color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Microsoft YaHei,Arial,sans-serif;
  line-height:1.72;
  -webkit-font-smoothing:antialiased;
}
a{color:var(--brand)}
button,input,select,textarea{font:inherit}
img{max-width:100%;display:block}

.top{
  background:#101827;
  color:#fff;
  border-bottom:1px solid rgba(255,255,255,.08);
  position:sticky;
  top:0;
  z-index:20;
}
.top-inner{
  max-width:1120px;
  margin:0 auto;
  padding:16px 22px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
}
.brand{
  font-weight:800;
  font-size:20px;
  display:flex;
  align-items:center;
  gap:10px;
  color:#fff;
  text-decoration:none;
  white-space:nowrap;
}
.brand:before{
  content:"";
  width:12px;
  height:12px;
  border-radius:50%;
  background:#2dd4bf;
  box-shadow:0 0 0 5px rgba(45,212,191,.14);
}
.nav{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
}
.nav a{
  color:#dbeafe;
  text-decoration:none;
  font-size:14px;
  padding:7px 10px;
  border-radius:6px;
}
.nav a:hover,.nav a.active{
  background:rgba(255,255,255,.10);
  color:#fff;
}

.wrap{
  max-width:1120px;
  margin:0 auto;
  padding:30px 22px 58px;
}

.hero{
  padding:34px 0 24px;
}
.home-hero{
  display:grid;
  grid-template-columns:minmax(0,1.12fr) minmax(300px,360px);
  gap:26px;
  align-items:stretch;
  padding:34px 0 20px;
}
.hero-copy{
  display:flex;
  flex-direction:column;
  justify-content:flex-end;
}
.hero h1{
  margin:0 0 10px;
  font-size:38px;
  line-height:1.18;
  letter-spacing:0;
}
.hero p{
  margin:0;
  color:var(--muted);
  font-size:16px;
  max-width:760px;
}
.home-hero .hero-copy p{
  max-width:720px;
}
.home-hero .hero-panel{
  display:grid;
  gap:10px;
  align-content:start;
}
.hero-panel a{
  display:grid;
  grid-template-columns:82px 1fr;
  gap:12px;
  align-items:center;
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:13px 14px;
  color:inherit;
  text-decoration:none;
  box-shadow:0 1px 0 rgba(16,24,40,.03);
  transition:border-color .15s ease,transform .15s ease,box-shadow .15s ease;
}
.hero-panel a:hover{
  border-color:#9ec5ff;
  box-shadow:0 10px 22px rgba(15,23,42,.08);
  transform:translateY(-1px);
}
.hero-panel strong{
  font-size:15px;
  font-weight:800;
  color:#0f172a;
}
.hero-panel span{
  font-size:13px;
  color:var(--muted);
  line-height:1.45;
}

.search-panel{
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:18px;
  margin:8px 0 24px;
  box-shadow:0 1px 0 rgba(16,24,40,.03);
}
.search-row{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto;
  gap:10px;
}
.search-input{
  width:100%;
  height:46px;
  border:1px solid var(--line);
  border-radius:8px;
  padding:0 14px;
  font-size:15px;
  background:#fbfdff;
}
.search-input:focus{
  outline:2px solid #bfdbfe;
  border-color:#93c5fd;
}
.quick-tags{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
  margin-top:12px;
}
.tag{
  border:1px solid var(--line);
  background:#f8fafc;
  color:#334155;
  border-radius:999px;
  padding:7px 11px;
  font-size:13px;
  font-weight:700;
  cursor:pointer;
}
.tag:hover,.tag.active{
  background:#e8f1ff;
  border-color:#93c5fd;
  color:#1d4ed8;
}
.search-meta{
  min-height:20px;
  margin-top:10px;
  color:var(--muted);
  font-size:13px;
}

.download-band{
  margin:24px 0 28px;
}
.download-grid{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:14px;
}
.download-card{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto;
  align-items:center;
  gap:18px;
  min-height:184px;
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:20px;
  box-shadow:0 1px 0 rgba(16,24,40,.03);
}
.download-card.android{
  border-top:4px solid var(--teal);
}
.download-card.windows{
  border-top:4px solid var(--brand);
}
.download-platform{
  display:inline-flex;
  align-items:center;
  min-height:26px;
  padding:3px 10px;
  border-radius:999px;
  background:#eef4ff;
  color:#1d4ed8;
  font-size:12px;
  font-weight:800;
}
.download-card.android .download-platform{
  background:#ecfdf5;
  color:#047857;
}
.download-card h3{
  margin:10px 0 6px;
  font-size:20px;
  line-height:1.3;
}
.download-card p{
  margin:0;
  color:var(--muted);
  font-size:14px;
  line-height:1.58;
}
.download-actions{
  display:grid;
  gap:10px;
  justify-items:start;
  min-width:178px;
}
.text-link{
  color:var(--brand);
  font-size:13px;
  font-weight:800;
  text-decoration:none;
}
.text-link:hover{
  text-decoration:underline;
}

.guide-band,
.guide-group{
  margin-top:28px;
}
.guide-band{
  padding:0;
}
.intro-section{
  margin-top:0;
}
.category-title{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:12px;
  margin:0 0 12px;
}
.category-title.compact{
  margin-bottom:14px;
}
.category-title h2{
  margin:0;
  font-size:23px;
  line-height:1.2;
}
.category-title span{
  font-size:13px;
  color:var(--muted);
}

.path-grid{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(260px,1fr));
  gap:14px;
}
.path{
  display:block;
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:18px;
  color:inherit;
  text-decoration:none;
  box-shadow:0 1px 0 rgba(16,24,40,.03);
  transition:border-color .15s ease,transform .15s ease,box-shadow .15s ease;
}
.path:hover{
  border-color:#9ec5ff;
  box-shadow:0 10px 22px rgba(15,23,42,.08);
  transform:translateY(-1px);
}
.path-index{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  width:42px;
  height:28px;
  border-radius:999px;
  background:#eef4ff;
  color:#1d4ed8;
  font-size:12px;
  font-weight:800;
  margin-bottom:10px;
}
.path strong{
  display:block;
  margin:0 0 8px;
  font-size:17px;
  line-height:1.35;
}
.path ol{
  margin:8px 0 0;
  padding-left:20px;
  color:#475467;
}

.grid{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(235px,1fr));
  gap:15px;
}
.card{
  position:relative;
  display:flex;
  flex-direction:column;
  min-height:178px;
  background:var(--panel);
  border:1px solid var(--line);
  border-radius:10px;
  padding:18px;
  text-decoration:none;
  color:inherit;
  box-shadow:0 1px 0 rgba(16,24,40,.03);
  transition:border-color .15s ease,transform .15s ease,box-shadow .15s ease;
  --accent:var(--brand);
}
.card:before{
  content:"";
  position:absolute;
  left:0;
  top:16px;
  bottom:16px;
  width:4px;
  border-radius:0 6px 6px 0;
  background:var(--accent);
}
.card:nth-child(3n+2){--accent:var(--teal)}
.card:nth-child(3n){--accent:var(--amber)}
.card:hover{
  border-color:#9ec5ff;
  box-shadow:var(--shadow);
  transform:translateY(-2px);
}
.card-kind{
  display:inline-flex;
  align-self:flex-start;
  padding:4px 9px;
  border-radius:999px;
  background:#eff6ff;
  color:#1d4ed8;
  font-size:12px;
  font-weight:800;
  margin-bottom:10px;
}
.card:nth-child(3n+2) .card-kind{
  background:#ecfdf5;
  color:#047857;
}
.card:nth-child(3n) .card-kind{
  background:#fff7ed;
  color:#b45309;
}
.card h2,.card h3{
  margin:0 0 7px;
  font-size:18px;
  line-height:1.35;
}
.card p{
  margin:0;
  color:var(--muted);
  font-size:14px;
  line-height:1.58;
}
.card-link{
  margin-top:auto;
  padding-top:14px;
  color:var(--accent);
  font-weight:800;
  font-size:13px;
  letter-spacing:0;
}
.help-card[hidden],
.guide-group[hidden]{
  display:none;
}

.section{
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:24px;
  margin:18px 0;
  box-shadow:0 1px 0 rgba(16,24,40,.03);
}
.section h2{
  margin:0 0 14px;
  font-size:24px;
  line-height:1.28;
}
.section h2:before{
  content:"";
  display:inline-block;
  width:8px;
  height:20px;
  background:var(--brand);
  border-radius:999px;
  margin-right:10px;
  vertical-align:-3px;
}
.section h3{
  margin:18px 0 8px;
  font-size:18px;
}
.section p{margin:8px 0}
.section ul,.section ol{
  padding-left:22px;
  margin:10px 0;
}
.note{
  border-left:4px solid var(--brand);
  background:#eef5ff;
  padding:12px 14px;
  margin:14px 0;
  border-radius:4px;
}
.contact-tip{
  border-left-color:var(--teal);
  background:#ecfdf5;
  color:#134e4a;
}
.contact-tip strong{
  color:#0f766e;
}
.warn{
  border-left-color:var(--amber);
  background:#fff7ed;
}
.ok{
  border-left-color:var(--green);
  background:#ecfdf5;
}
.steps{counter-reset:step}
.step{
  display:grid;
  grid-template-columns:42px 1fr;
  gap:13px;
  margin:15px 0;
}
.step:before{
  counter-increment:step;
  content:counter(step);
  width:34px;
  height:34px;
  border-radius:50%;
  background:var(--brand);
  color:#fff;
  display:flex;
  align-items:center;
  justify-content:center;
  font-weight:800;
  box-shadow:0 8px 16px rgba(31,111,235,.22);
}
.table{
  width:100%;
  border-collapse:separate;
  border-spacing:0;
  margin:12px 0;
  border:1px solid var(--line);
  border-radius:10px;
  overflow:hidden;
}
.table th,.table td{
  border-bottom:1px solid var(--line);
  padding:11px;
  text-align:left;
  vertical-align:top;
}
.table tr:last-child td{border-bottom:0}
.table th{
  background:#f2f6fc;
  font-weight:700;
}
.breadcrumbs{
  font-size:13px;
  color:var(--muted);
  margin:0 0 14px;
}
.breadcrumbs a{
  color:var(--brand);
  text-decoration:none;
}
.page-actions{
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin:18px 0;
}
.btn{
  display:inline-block;
  background:var(--brand);
  color:#fff;
  text-decoration:none;
  padding:10px 14px;
  border-radius:6px;
  margin:0;
  font-weight:700;
  border:0;
}
.btn:hover{background:var(--brand-dark)}
.btn.secondary{background:#374151}
.button-row{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
  align-items:center;
  margin:14px 0;
}
.hash-value{
  display:block;
  padding:10px 12px;
  border:1px solid var(--line);
  border-radius:6px;
  background:#f8fafc;
  color:#334155;
  font-family:Consolas,Monaco,monospace;
  font-size:12px;
  line-height:1.55;
  overflow-wrap:anywhere;
}
.fact-list{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:10px;
  margin:14px 0;
}
.fact-list div{
  border:1px solid var(--line);
  border-radius:8px;
  background:#f8fafc;
  padding:12px;
}
.fact-list strong,.fact-list span{display:block}
.fact-list span{color:var(--muted);font-size:13px;margin-top:2px}
.footer{
  color:var(--muted);
  font-size:13px;
  margin-top:32px;
  border-top:1px solid var(--line);
  padding-top:18px;
}

.visual{
  display:grid;
  grid-template-columns:minmax(220px,340px) 1fr;
  gap:22px;
  align-items:start;
  margin:22px 0;
}
.mock{
  background:#111827;
  border-radius:18px;
  padding:14px;
  box-shadow:0 18px 36px rgba(15,23,42,.18);
}
.phone{
  max-width:290px;
  margin:auto;
  background:#0b1220;
  border-radius:28px;
  padding:14px;
  border:6px solid #1f2937;
}
.screen{
  background:#f8fafc;
  border-radius:20px;
  min-height:420px;
  padding:14px;
  color:#111827;
}
.desktop{
  background:#0f172a;
  border-radius:12px;
  padding:10px;
}
.desktop .screen{
  border-radius:6px;
  min-height:300px;
}
.bar{
  height:10px;
  background:#dbe3ef;
  border-radius:999px;
  margin:8px 0;
}
.bar.short{width:58%}
.bar.mid{width:76%}
.pill{
  display:inline-block;
  background:#e0edff;
  color:#1d4ed8;
  border-radius:999px;
  padding:6px 10px;
  font-size:13px;
  margin:4px;
}
.primary-ui{
  background:var(--brand);
  color:#fff;
  border-radius:8px;
  padding:10px 12px;
  text-align:center;
  margin:10px 0;
  font-weight:800;
}
.danger-ui{
  background:#fff7ed;
  color:#b45309;
  border:1px solid #fed7aa;
  border-radius:8px;
  padding:10px;
  margin:10px 0;
}
.list-ui{
  border:1px solid #d9dee8;
  border-radius:10px;
  background:#fff;
  margin:10px 0;
  overflow:hidden;
}
.list-ui div{
  padding:10px 12px;
  border-bottom:1px solid #eef2f7;
}
.list-ui div:last-child{border-bottom:0}
.node{
  display:flex;
  justify-content:space-between;
  gap:8px;
}
.node b{color:#111827}
.switch{
  width:54px;
  height:28px;
  background:#22c55e;
  border-radius:999px;
  position:relative;
}
.switch:after{
  content:"";
  position:absolute;
  right:4px;
  top:4px;
  width:20px;
  height:20px;
  background:#fff;
  border-radius:50%;
}
.callout{
  border:2px solid var(--brand);
  background:#eff6ff;
  border-radius:10px;
  padding:10px;
  margin:10px 0;
  font-weight:800;
  color:#1d4ed8;
}
.caption{
  font-size:13px;
  color:var(--muted);
  text-align:center;
  margin-top:9px;
}
.toc{
  background:#fff;
  border:1px solid var(--line);
  border-radius:10px;
  padding:14px;
  margin:14px 0;
}
.toc a{
  display:inline-block;
  margin:4px 10px 4px 0;
  color:var(--brand);
  font-weight:700;
}
.next-grid{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(220px,1fr));
  gap:12px;
}
.mini-card{
  display:block;
  border:1px solid var(--line);
  background:#fff;
  border-radius:10px;
  padding:14px;
  text-decoration:none;
  color:inherit;
}
.mini-card:hover{
  border-color:#9ec5ff;
  box-shadow:0 8px 20px rgba(15,23,42,.08);
}
.mini-card strong{
  display:block;
  margin-bottom:4px;
}
.mini-card span{
  font-size:13px;
  color:var(--muted);
}

@media(max-width:760px){
  .fact-list{grid-template-columns:1fr}
  .button-row .btn{width:100%;text-align:center}
  .top-inner{
    align-items:flex-start;
    flex-direction:column;
    padding:14px 18px;
  }
  .nav{
    width:100%;
    display:grid;
    grid-template-columns:repeat(2,minmax(0,1fr));
  }
  .nav a{
    text-align:center;
    background:rgba(255,255,255,.06);
  }
  .wrap{padding:20px 16px 44px}
  .hero h1{font-size:31px}
  .home-hero{
    grid-template-columns:1fr;
    gap:16px;
    padding:24px 0 14px;
  }
  .hero-panel a{
    grid-template-columns:74px 1fr;
    padding:12px 13px;
  }
  .search-row{grid-template-columns:1fr}
  .btn{
    width:100%;
    text-align:center;
  }
  .download-grid{grid-template-columns:1fr}
  .download-card{
    grid-template-columns:1fr;
    min-height:0;
    padding:18px;
  }
  .download-actions{
    width:100%;
    min-width:0;
  }
  .grid{grid-template-columns:1fr}
  .path-grid{grid-template-columns:1fr}
  .category-title{
    flex-direction:column;
    align-items:flex-start;
    gap:4px;
    margin-bottom:10px;
  }
  .section{padding:18px}
  .card{
    min-height:0;
  }
  .card-link{
    padding-top:12px;
  }
  .visual{grid-template-columns:1fr}
  .mock{max-width:360px;margin:auto}
  .step{grid-template-columns:36px 1fr}
}

@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .card,.path,.hero-panel a,.mini-card{transition:none}
  .card:hover{transform:none}
  .path:hover{transform:none}
  .hero-panel a:hover{transform:none}
}