/* =========================================================
   SinoCount — Design System
   Off-white surface, dark type, single accent, generous spacing.
   ========================================================= */

:root{
  --sc-bg: #FAFAF8;
  --sc-surface: #FFFFFF;
  --sc-surface-muted: #F3F3EF;
  --sc-border: #E4E4DE;
  --sc-text: #1C1C1A;
  --sc-text-muted: #5B5B55;
  --sc-accent: #B33A2E;      /* single accent — warm vermillion, nods to Chinese seal-red without being garish */
  --sc-accent-ink: #FFFFFF;
  --sc-accent-soft: #F6E7E4;
  --sc-success: #2E7D4F;
  --sc-radius-sm: 8px;
  --sc-radius-md: 14px;
  --sc-radius-lg: 20px;
  --sc-shadow-sm: 0 1px 2px rgba(20,20,15,0.06);
  --sc-shadow-md: 0 6px 20px rgba(20,20,15,0.08);
  --sc-max: 1120px;
  --sc-font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, "Helvetica Neue", Arial, sans-serif;
  --sc-font-cjk: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", var(--sc-font-sans);
}

@media (prefers-color-scheme: dark){
  :root{
    --sc-bg:#141412; --sc-surface:#1B1B18; --sc-surface-muted:#212119;
    --sc-border:#33332C; --sc-text:#F3F3EE; --sc-text-muted:#B3B3A8;
    --sc-accent:#E2624F; --sc-accent-soft:#2C1E1B;
  }
}
html[data-theme="dark"]{
  --sc-bg:#141412; --sc-surface:#1B1B18; --sc-surface-muted:#212119;
  --sc-border:#33332C; --sc-text:#F3F3EE; --sc-text-muted:#B3B3A8;
  --sc-accent:#E2624F; --sc-accent-soft:#2C1E1B;
}
html[data-theme="light"]{
  --sc-bg:#FAFAF8; --sc-surface:#FFFFFF; --sc-surface-muted:#F3F3EF;
  --sc-border:#E4E4DE; --sc-text:#1C1C1A; --sc-text-muted:#5B5B55; --sc-accent:#B33A2E; --sc-accent-soft:#F6E7E4;
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto;}
  *{animation-duration:0.001ms !important; animation-iteration-count:1 !important; transition-duration:0.001ms !important;}
}
body{
  margin:0; background:var(--sc-bg); color:var(--sc-text);
  font-family:var(--sc-font-sans); line-height:1.6; font-size:16px;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%; height:auto; display:block;}
a{color:var(--sc-accent);}
.sc-container{max-width:var(--sc-max); margin:0 auto; padding:0 20px;}
.sc-visually-hidden{position:absolute; width:1px; height:1px; overflow:hidden; clip:rect(0 0 0 0); white-space:nowrap;}
.sc-skip-link{position:absolute; left:-9999px; top:0; background:var(--sc-accent); color:#fff; padding:10px 16px; z-index:1000; border-radius:0 0 8px 0;}
.sc-skip-link:focus{left:0;}

/* ---------- Header ---------- */
.sc-header{
  position:sticky; top:0; z-index:50; background:var(--sc-surface);
  border-bottom:1px solid var(--sc-border);
}
.sc-header-inner{display:flex; align-items:center; justify-content:space-between; gap:16px; padding:14px 20px; max-width:var(--sc-max); margin:0 auto;}
.sc-logo{display:flex; align-items:center; gap:8px; font-weight:700; font-size:1.15rem; color:var(--sc-text); text-decoration:none;}
.sc-logo-mark{width:30px; height:30px; border-radius:8px; background:var(--sc-accent); color:#fff; display:flex; align-items:center; justify-content:center; font-family:var(--sc-font-cjk); font-weight:700;}
.sc-nav{display:flex; align-items:center; gap:22px;}
.sc-nav a{color:var(--sc-text); text-decoration:none; font-size:0.95rem; font-weight:500;}
.sc-nav a:hover{color:var(--sc-accent);}
.sc-nav-toggle{display:none; background:none; border:1px solid var(--sc-border); border-radius:8px; padding:8px 10px; cursor:pointer;}
.sc-theme-toggle{background:none; border:1px solid var(--sc-border); border-radius:999px; padding:6px 12px; cursor:pointer; font-size:0.85rem; color:var(--sc-text);}
@media (max-width: 860px){
  .sc-nav{position:fixed; inset:60px 0 0 0; background:var(--sc-surface); flex-direction:column; align-items:flex-start; padding:20px; gap:16px; transform:translateY(-8px); opacity:0; pointer-events:none; transition:opacity .15s ease, transform .15s ease; overflow:auto;}
  .sc-nav.is-open{opacity:1; transform:translateY(0); pointer-events:auto;}
  .sc-nav-toggle{display:block;}
}

/* ---------- Breadcrumbs ---------- */
.sc-breadcrumbs{font-size:0.85rem; color:var(--sc-text-muted); padding:14px 0 0;}
.sc-breadcrumbs a{color:var(--sc-text-muted); text-decoration:none;}
.sc-breadcrumbs a:hover{color:var(--sc-accent);}

/* ---------- Hero / Tool shell ---------- */
.sc-hero{padding:28px 0 8px;}
.sc-hero h1{font-size:clamp(1.7rem, 3.4vw, 2.5rem); margin:0 0 8px; letter-spacing:-0.01em;}
.sc-hero p.sc-sub{color:var(--sc-text-muted); font-size:1.05rem; max-width:62ch; margin:0;}

.sc-tool{
  background:var(--sc-surface); border:1px solid var(--sc-border); border-radius:var(--sc-radius-lg);
  box-shadow:var(--sc-shadow-md); padding:20px; margin:22px 0 8px;
}
.sc-tool-toolbar{display:flex; flex-wrap:wrap; gap:8px; justify-content:space-between; align-items:center; margin-bottom:10px;}
.sc-tool-toolbar-left{display:flex; gap:8px; flex-wrap:wrap; align-items:center;}
.sc-btn{
  border:1px solid var(--sc-border); background:var(--sc-surface-muted); color:var(--sc-text);
  border-radius:var(--sc-radius-sm); padding:8px 14px; font-size:0.88rem; font-weight:600; cursor:pointer;
  display:inline-flex; align-items:center; gap:6px; transition:background .12s ease, transform .06s ease;
}
.sc-btn:hover{background:var(--sc-border);}
.sc-btn:active{transform:scale(0.98);}
.sc-btn-primary{background:var(--sc-accent); color:var(--sc-accent-ink); border-color:var(--sc-accent);}
.sc-btn-primary:hover{filter:brightness(1.06);}
.sc-btn:focus-visible, a:focus-visible, input:focus-visible, textarea:focus-visible, button:focus-visible{
  outline:3px solid var(--sc-accent); outline-offset:2px;
}

.sc-textarea-wrap{position:relative;}
.sc-textarea{
  width:100%; min-height:260px; resize:vertical; padding:16px; border-radius:var(--sc-radius-md);
  border:1px solid var(--sc-border); background:var(--sc-bg); color:var(--sc-text);
  font-family:var(--sc-font-cjk); font-size:1.05rem; line-height:1.8;
}
.sc-textarea.sc-compact{min-height:140px;}
.sc-limit-row{display:flex; gap:10px; align-items:center; margin-top:8px; font-size:0.85rem; color:var(--sc-text-muted); flex-wrap:wrap;}
.sc-limit-row input[type="number"]{width:90px; padding:6px 8px; border-radius:6px; border:1px solid var(--sc-border); background:var(--sc-surface); color:var(--sc-text);}
.sc-limit-bar{height:6px; border-radius:999px; background:var(--sc-border); overflow:hidden; flex:1 1 160px; min-width:120px;}
.sc-limit-bar-fill{height:100%; background:var(--sc-accent); width:0%; transition:width .12s ease;}
.sc-limit-bar-fill.sc-over{background:#C0392B;}

.sc-stats-grid{display:grid; grid-template-columns:repeat(auto-fit, minmax(120px,1fr)); gap:10px; margin-top:16px;}
.sc-stat{background:var(--sc-surface-muted); border:1px solid var(--sc-border); border-radius:var(--sc-radius-md); padding:14px; text-align:left;}
.sc-stat .sc-stat-num{font-size:1.5rem; font-weight:700; font-variant-numeric:tabular-nums; display:block;}
.sc-stat .sc-stat-label{font-size:0.8rem; color:var(--sc-text-muted);}
.sc-stat.sc-stat-highlight{border-color:var(--sc-accent); background:var(--sc-accent-soft);}

.sc-breakdown{margin-top:16px; border-top:1px solid var(--sc-border); padding-top:14px;}
.sc-breakdown-toggle{background:none; border:none; color:var(--sc-accent); font-weight:600; cursor:pointer; padding:4px 0; font-size:0.9rem;}
.sc-breakdown-body{display:none; margin-top:10px;}
.sc-breakdown-body.is-open{display:grid; grid-template-columns:repeat(auto-fit, minmax(140px,1fr)); gap:8px;}
.sc-breakdown-row{display:flex; justify-content:space-between; font-size:0.88rem; padding:6px 10px; background:var(--sc-surface-muted); border-radius:8px;}
.sc-breakdown-row span:last-child{font-weight:600; font-variant-numeric:tabular-nums;}

.sc-tool-footnote{margin-top:12px; font-size:0.82rem; color:var(--sc-text-muted);}
.sc-toast{position:fixed; bottom:20px; left:50%; transform:translate(-50%, 10px); background:var(--sc-text); color:var(--sc-bg); padding:10px 16px; border-radius:999px; font-size:0.85rem; opacity:0; pointer-events:none; transition:opacity .15s ease, transform .15s ease; z-index:100;}
.sc-toast.is-visible{opacity:1; transform:translate(-50%, 0);}

/* ---------- Ad slot ---------- */
.sc-ad-slot{margin:28px 0; text-align:center; min-height:0;}
.sc-ad-slot .sc-ad-label{font-size:0.7rem; letter-spacing:0.06em; text-transform:uppercase; color:var(--sc-text-muted); margin-bottom:6px;}

/* ---------- Content sections ---------- */
.sc-section{padding:34px 0;}
.sc-section h2{font-size:1.5rem; margin:0 0 12px;}
.sc-section h3{font-size:1.15rem; margin:20px 0 8px;}
.sc-prose{max-width:74ch;}
.sc-prose table{width:100%; border-collapse:collapse; margin:16px 0;}
.sc-prose th, .sc-prose td{border:1px solid var(--sc-border); padding:10px 12px; text-align:left; font-size:0.92rem;}
.sc-prose th{background:var(--sc-surface-muted);}

.sc-card-grid{display:grid; grid-template-columns:repeat(auto-fit, minmax(230px,1fr)); gap:16px;}
.sc-card{background:var(--sc-surface); border:1px solid var(--sc-border); border-radius:var(--sc-radius-md); padding:18px; text-decoration:none; color:var(--sc-text); box-shadow:var(--sc-shadow-sm);}
.sc-card:hover{border-color:var(--sc-accent);}
.sc-card h3{margin:8px 0 6px; font-size:1.05rem;}
.sc-card p{margin:0; color:var(--sc-text-muted); font-size:0.92rem;}
.sc-card .sc-card-icon{width:34px; height:34px; border-radius:9px; background:var(--sc-accent-soft); color:var(--sc-accent); display:flex; align-items:center; justify-content:center; font-weight:700; font-family:var(--sc-font-cjk);}

.sc-faq-item{border-bottom:1px solid var(--sc-border);}
.sc-faq-q{width:100%; text-align:left; background:none; border:none; padding:14px 0; font-weight:600; font-size:1rem; cursor:pointer; display:flex; justify-content:space-between; gap:12px; color:var(--sc-text);}
.sc-faq-a{display:none; padding:0 0 16px; color:var(--sc-text-muted);}
.sc-faq-item.is-open .sc-faq-a{display:block;}
.sc-faq-item.is-open .sc-faq-q .sc-faq-icon{transform:rotate(45deg);}
.sc-faq-icon{transition:transform .12s ease;}

.sc-steps{counter-reset:sc-step; list-style:none; padding:0; display:grid; gap:14px;}
.sc-steps li{position:relative; padding-left:44px;}
.sc-steps li::before{counter-increment:sc-step; content:counter(sc-step); position:absolute; left:0; top:0; width:30px; height:30px; border-radius:50%; background:var(--sc-accent-soft); color:var(--sc-accent); font-weight:700; display:flex; align-items:center; justify-content:center; font-size:0.9rem;}

/* ---------- Footer ---------- */
.sc-footer{border-top:1px solid var(--sc-border); background:var(--sc-surface); margin-top:40px; padding:36px 0 24px;}
.sc-footer-grid{display:grid; grid-template-columns:2fr repeat(4, 1fr); gap:24px;}
.sc-footer h4{font-size:0.85rem; text-transform:uppercase; letter-spacing:0.05em; color:var(--sc-text-muted); margin:0 0 10px;}
.sc-footer ul{list-style:none; padding:0; margin:0; display:grid; gap:8px;}
.sc-footer a{color:var(--sc-text); text-decoration:none; font-size:0.92rem;}
.sc-footer a:hover{color:var(--sc-accent);}
.sc-footer-desc{color:var(--sc-text-muted); font-size:0.9rem; max-width:38ch;}
.sc-footer-bottom{margin-top:26px; padding-top:16px; border-top:1px solid var(--sc-border); font-size:0.82rem; color:var(--sc-text-muted); display:flex; justify-content:space-between; flex-wrap:wrap; gap:8px;}
@media (max-width: 780px){ .sc-footer-grid{grid-template-columns:1fr 1fr;} }

/* ---------- 404 ---------- */
.sc-404{padding:80px 0; text-align:center;}
.sc-404 .sc-404-actions{display:flex; gap:10px; justify-content:center; margin-top:20px; flex-wrap:wrap;}

/* ---------- Utility ---------- */
.sc-mt-0{margin-top:0;}
.sc-flex{display:flex; gap:10px; flex-wrap:wrap;}
.sc-tag{display:inline-block; background:var(--sc-surface-muted); border:1px solid var(--sc-border); border-radius:999px; padding:3px 10px; font-size:0.78rem; color:var(--sc-text-muted);}