:root{
  --bg:#111827; --card:#1c2536; --card2:#222d42;
  --sidebar:#ffffff; --side-text:#374151; --side-dim:#6b7280;
  --text:#e9edf4; --muted:#98a2b6; --line:#2c3850;
  --indigo:#6366f1; --cyan:#22d3ee; --green:#34d399; --amber:#fbbf24; --pink:#f472b6;
  --radius:14px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:'Inter',system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.65;font-size:16px}
.wrap{max-width:1080px;margin:0 auto;padding:0 24px}

/* ---------- layout: light sidebar + dark content ---------- */
.shell{display:flex;min-height:100vh}
.sidebar{width:248px;flex:0 0 248px;background:var(--sidebar);color:var(--side-text);
  position:sticky;top:0;height:100vh;display:flex;flex-direction:column;
  border-right:1px solid #e5e7eb;z-index:50}
.side-brand{display:flex;align-items:center;gap:10px;padding:22px 20px 16px;text-decoration:none}
.side-brand svg{width:34px;height:34px}
.side-brand b{color:#111827;font-family:'Sora',sans-serif;font-size:1.15rem;letter-spacing:-.02em}
.side-brand b em{font-style:normal;color:var(--indigo)}
.side-tag{font-size:.72rem;color:var(--side-dim);padding:0 20px 14px}
.side-nav{display:flex;flex-direction:column;gap:2px;padding:6px 12px;flex:1;overflow:auto}
.side-nav a{display:flex;align-items:center;gap:11px;padding:10px 12px;border-radius:10px;
  color:var(--side-text);text-decoration:none;font-weight:500;font-size:.93rem;border-left:3px solid transparent}
.side-nav a svg{width:18px;height:18px;flex:0 0 18px;stroke:var(--side-dim)}
.side-nav a:hover{background:#f3f4f6}
.side-nav a.active{background:#eef2ff;border-left-color:var(--indigo);color:#1e1b4b;font-weight:700}
.side-nav a.active svg{stroke:var(--indigo)}
.side-nav a.tool-link.active{background:#ecfdf5;border-left-color:var(--green);color:#064e3b}
.side-nav a.tool-link.active svg{stroke:var(--green)}
.side-foot{padding:14px 20px;font-size:.74rem;color:var(--side-dim);border-top:1px solid #eef0f3}
.main{flex:1;min-width:0;display:flex;flex-direction:column}
.mobile-top{display:none}
.content{flex:1;padding:40px 0 60px}

/* ---------- hero ---------- */
.hero{padding:26px 0 34px}
.eyebrow{display:inline-flex;align-items:center;gap:8px;font-size:.78rem;font-weight:600;
  letter-spacing:.08em;text-transform:uppercase;color:var(--cyan);
  background:rgba(34,211,238,.08);border:1px solid rgba(34,211,238,.25);
  padding:7px 14px;border-radius:999px;margin-bottom:18px}
.hero h1{font-family:'Sora',sans-serif;font-size:clamp(1.9rem,4.2vw,3rem);line-height:1.14;
  letter-spacing:-.03em;color:#fff;max-width:640px}
.hero h1 .hl{color:var(--cyan)}
.hero .lede{color:var(--muted);font-size:1.08rem;max-width:640px;margin-top:14px}
.hero .lede strong{color:var(--text)}
.stat-strip{display:flex;gap:0;margin-top:26px;background:var(--card);border:1px solid var(--line);
  border-radius:var(--radius);overflow:hidden}
.stat{flex:1;padding:16px 18px;border-right:1px solid var(--line)}
.stat:last-child{border-right:0}
.stat .n{font-family:'Sora',sans-serif;font-weight:800;font-size:1.5rem;display:block;line-height:1.1}
.stat .l{font-size:.78rem;color:var(--muted)}
.stat.s1 .n{color:var(--indigo)} .stat.s2 .n{color:var(--cyan)}
.stat.s3 .n{color:var(--green)} .stat.s4 .n{color:var(--amber)}

/* bar-chart motif */
.chart-motif{display:flex;align-items:flex-end;gap:10px;height:120px;margin-top:30px;padding:0 4px}
.chart-motif .bar{flex:1;max-width:64px;border-radius:6px 6px 3px 3px;min-height:14px;
  background:linear-gradient(180deg,var(--indigo),#4338ca);transform-origin:bottom;
  animation:grow 1.6s ease-out both}
.chart-motif .bar:nth-child(2n){background:linear-gradient(180deg,var(--cyan),#0e7490)}
.chart-motif .bar:nth-child(3n){background:linear-gradient(180deg,var(--green),#047857)}
@keyframes grow{from{transform:scaleY(.15)}to{transform:scaleY(1)}}
@media (prefers-reduced-motion:reduce){.chart-motif .bar{animation:none}}

/* ---------- tool console ---------- */
.console{background:var(--card);border:1px solid var(--line);border-radius:18px;overflow:hidden;margin-top:34px}
.console-bar{display:flex;align-items:center;gap:12px;padding:13px 18px;background:var(--card2);
  border-bottom:1px solid var(--line);flex-wrap:wrap}
.traffic{display:flex;gap:7px}
.traffic i{width:11px;height:11px;border-radius:50%;background:#3a4763}
.traffic i:nth-child(1){background:#f87171}.traffic i:nth-child(2){background:#fbbf24}.traffic i:nth-child(3){background:#34d399}
.console-title{font-family:'JetBrains Mono',monospace;font-size:.82rem;color:var(--muted)}
.privacy-chip{margin-left:auto;display:inline-flex;align-items:center;gap:7px;font-size:.76rem;font-weight:700;
  color:var(--green);background:rgba(52,211,153,.1);border:1px solid rgba(52,211,153,.35);
  padding:6px 12px;border-radius:999px}
.privacy-chip svg{width:14px;height:14px}
.console-body{padding:26px}
.opts{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-bottom:22px}
.opt-label{display:block;font-size:.8rem;font-weight:700;letter-spacing:.05em;text-transform:uppercase;
  color:var(--muted);margin-bottom:9px}
.topic-input{width:100%;background:var(--bg);border:1px solid var(--line);border-radius:10px;
  color:var(--text);font-size:1rem;padding:12px 14px;font-family:inherit}
.topic-input:focus{outline:2px solid var(--indigo);border-color:var(--indigo)}
.seg{display:flex;flex-wrap:wrap;gap:8px}
.seg button{background:var(--bg);border:1px solid var(--line);color:var(--text);
  padding:9px 14px;border-radius:9px;font-size:.9rem;font-weight:600;cursor:pointer;font-family:inherit}
.seg button:hover{border-color:var(--indigo)}
.seg button[aria-pressed="true"]{background:var(--indigo);border-color:var(--indigo);color:#fff}
.opt-hint{font-size:.8rem;color:var(--muted);margin-top:7px}
.num-row{display:flex;align-items:center;gap:12px}
input[type=range]{flex:1;accent-color:var(--indigo)}
.range-val{font-family:'JetBrains Mono',monospace;font-weight:700;color:var(--cyan);min-width:2ch;text-align:right}
.actions{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-bottom:20px}
.btn{display:inline-flex;align-items:center;gap:8px;background:var(--card2);border:1px solid var(--line);
  color:var(--text);padding:12px 20px;border-radius:11px;font-size:.95rem;font-weight:700;
  cursor:pointer;text-decoration:none;font-family:inherit;transition:transform .12s ease,box-shadow .12s ease}
.btn svg{width:17px;height:17px}
.btn.primary{background:var(--indigo);border-color:var(--indigo);color:#fff;box-shadow:0 6px 22px rgba(99,102,241,.35)}
.btn.primary:hover{transform:translateY(-1px)}
.btn:disabled{opacity:.45;cursor:not-allowed;transform:none}
.btn.ghost{background:transparent}
.copy-note{font-size:.85rem;color:var(--green);font-weight:600;min-height:1.4em}
.output{background:var(--bg);border:1px dashed var(--line);border-radius:12px;padding:18px;min-height:120px}
.output ul{list-style:none;display:flex;flex-direction:column;gap:8px}
.output li{display:flex;align-items:center;gap:12px;background:var(--card);border:1px solid var(--line);
  border-radius:10px;padding:11px 14px;cursor:pointer;transition:border-color .12s}
.output li:hover{border-color:var(--cyan)}
.output li .t{flex:1;font-size:.96rem}
.output li .cp{font-size:.74rem;font-weight:700;color:var(--muted);text-transform:uppercase;letter-spacing:.06em;
  border:1px solid var(--line);border-radius:6px;padding:3px 9px}
.output li:hover .cp{color:var(--cyan);border-color:var(--cyan)}
.output li.copied{border-color:var(--green)}
.output li.copied .cp{color:var(--green);border-color:var(--green)}
.placeholder{color:var(--muted);font-size:.95rem;text-align:center;padding:34px 10px}
.output-meta{font-size:.8rem;color:var(--muted);margin-top:10px;font-family:'JetBrains Mono',monospace}
.limits{margin-top:22px;background:rgba(251,191,36,.06);border:1px solid rgba(251,191,36,.3);
  border-radius:12px;padding:18px 20px}
.limits h3{display:flex;align-items:center;gap:9px;font-size:1rem;color:var(--amber);margin-bottom:10px}
.limits h3 svg{width:20px;height:20px}
.limits ul{padding-left:20px;color:var(--muted);font-size:.92rem;display:flex;flex-direction:column;gap:7px}
.limits li strong{color:var(--text)}

/* ---------- content sections ---------- */
.section{margin-top:56px}
.section h2{font-family:'Sora',sans-serif;font-size:1.7rem;letter-spacing:-.02em;color:#fff;margin-bottom:10px}
.section h2 .hl{color:var(--cyan)}
.sub{color:var(--muted);max-width:680px;margin-bottom:22px}
.cards3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.card svg{width:26px;height:26px;stroke:var(--cyan);margin-bottom:12px}
.card .n{font-family:'JetBrains Mono',monospace;font-size:.74rem;color:var(--muted);
  text-transform:uppercase;letter-spacing:.1em;display:block;margin-bottom:8px}
.card h3{font-size:1.08rem;color:#fff;margin-bottom:8px}
.card p{color:var(--muted);font-size:.94rem}
.card code{font-family:'JetBrains Mono',monospace;font-size:.85em;background:var(--bg);padding:2px 6px;border-radius:5px}
a.card-link{text-decoration:none;display:block;transition:transform .12s,border-color .12s}
a.card-link:hover{transform:translateY(-3px);border-color:var(--indigo)}
.go{display:inline-block;margin-top:12px;color:var(--cyan);font-weight:700;font-size:.9rem}
.cta-box{margin-top:26px;background:linear-gradient(135deg,#312e81,#1e1b4b);border:1px solid #4c4fa8;
  border-radius:var(--radius);padding:28px;display:flex;align-items:center;gap:24px;flex-wrap:wrap}
.cta-box h3{color:#fff;font-size:1.25rem;margin-bottom:6px}
.cta-box p{color:#c7d2fe;max-width:520px}
.cta-box .btn{margin-left:auto}
.faq details{background:var(--card);border:1px solid var(--line);border-radius:12px;margin-bottom:10px;overflow:hidden}
.faq summary{padding:16px 20px;cursor:pointer;font-weight:600;color:#fff;list-style:none;
  display:flex;justify-content:space-between;align-items:center;gap:14px}
.faq summary::-webkit-details-marker{display:none}
.faq summary .plus{color:var(--cyan);font-size:1.3rem;font-weight:400}
.faq .answer{padding:0 20px 18px;color:var(--muted)}
.faq .answer a{color:var(--cyan)}
.faq .answer strong{color:var(--text)}

/* ---------- article pages ---------- */
.crumb{font-size:.82rem;color:var(--muted);margin-bottom:14px}
.crumb a{color:var(--cyan);text-decoration:none}
.article h1{font-family:'Sora',sans-serif;font-size:clamp(1.7rem,3.6vw,2.5rem);letter-spacing:-.025em;
  color:#fff;line-height:1.2;margin-bottom:14px;max-width:760px}
.article .lede{color:var(--muted);font-size:1.06rem;max-width:720px;margin-bottom:30px}
.article .lede strong{color:var(--text)}
.article h2{font-family:'Sora',sans-serif;font-size:1.45rem;color:#fff;margin:34px 0 12px;letter-spacing:-.015em}
.article h2 .hl{color:var(--cyan)}
.article h3{font-size:1.12rem;color:#fff;margin:24px 0 8px}
.article p{color:#c4cbd9;margin-bottom:14px;max-width:760px}
.article p strong,.article li strong{color:var(--text)}
.article ul,.article ol{color:#c4cbd9;margin:0 0 16px 22px;max-width:740px;display:flex;flex-direction:column;gap:8px}
.article a{color:var(--cyan)}
.article .tip{background:var(--card);border-left:4px solid var(--green);border-radius:0 12px 12px 0;
  padding:16px 20px;margin:22px 0;max-width:760px}
.article .tip p{margin:0;color:#c4cbd9}
.article .warn{background:rgba(251,191,36,.07);border-left:4px solid var(--amber);border-radius:0 12px 12px 0;
  padding:16px 20px;margin:22px 0;max-width:760px}
.article .warn p{margin:0;color:#c4cbd9}
.example{background:var(--bg);border:1px solid var(--line);border-radius:10px;padding:14px 18px;
  margin:14px 0;max-width:760px;font-family:'JetBrains Mono',monospace;font-size:.88rem;color:var(--cyan)}
.article table{width:100%;max-width:760px;border-collapse:collapse;margin:18px 0;font-size:.92rem}
.article th{background:var(--card2);color:#fff;text-align:left;padding:11px 14px;border:1px solid var(--line)}
.article td{padding:11px 14px;border:1px solid var(--line);color:#c4cbd9;vertical-align:top}
.related{margin-top:44px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px}
.related h3{color:#fff;margin-bottom:12px;font-size:1.05rem}
.related ul{list-style:none;margin:0;display:flex;flex-direction:column;gap:8px}

/* ---------- footer ---------- */
footer{border-top:1px solid var(--line);padding:40px 0 30px;margin-top:20px}
.foot-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:28px;margin-bottom:26px}
.foot-brand p{color:var(--muted);font-size:.9rem;margin-top:10px;max-width:300px}
.foot-col h4{color:#fff;font-size:.82rem;text-transform:uppercase;letter-spacing:.08em;margin-bottom:12px}
.foot-col a{display:block;color:var(--muted);text-decoration:none;font-size:.92rem;margin-bottom:8px}
.foot-col a:hover{color:var(--cyan)}
.foot-base{display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;font-size:.78rem;color:var(--side-dim,#6b7280);border-top:1px solid var(--line);padding-top:18px}

/* ---------- responsive ---------- */
@media(max-width:900px){
  .sidebar{display:none}
  .mobile-top{display:flex;align-items:center;justify-content:space-between;gap:12px;
    background:var(--sidebar);padding:12px 18px;position:sticky;top:0;z-index:60;border-bottom:1px solid #e5e7eb}
  .mobile-top .side-brand{padding:0}
  .mobile-top nav{display:flex;gap:4px;overflow-x:auto}
  .mobile-top nav a{color:var(--side-text);text-decoration:none;font-size:.82rem;font-weight:600;
    padding:8px 10px;white-space:nowrap;border-radius:8px}
  .mobile-top nav a.active{background:#eef2ff;color:#1e1b4b}
  .opts{grid-template-columns:1fr}
  .cards3{grid-template-columns:1fr}
  .foot-grid{grid-template-columns:1fr}
  .stat-strip{flex-wrap:wrap}
  .stat{flex:1 1 40%}
}