:root{--teal:#2cbf92;--blue:#6292d9;--ink:#0f172a;--muted:#64748b;--bg:#f6faf9;--line:#e2e8f0;--paper:#ffffff;}
*{box-sizing:border-box;}
body{margin:0;background:var(--bg);color:var(--ink);font-family:'Inter',system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;font-size:17px;line-height:1.7;-webkit-font-smoothing:antialiased;}
a{color:var(--blue);text-decoration:none;}
a:hover{text-decoration:underline;}
img{max-width:100%;}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px;}

/* header */
.site-header{background:rgba(255,255,255,.85);backdrop-filter:blur(10px);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50;}
.site-header .bar{display:flex;align-items:center;justify-content:space-between;height:64px;}
.logo{font-weight:900;font-size:20px;letter-spacing:-.3px;text-transform:uppercase;color:var(--ink);}
.logo:hover{text-decoration:none;}
.logo span{color:var(--teal);}
.site-header nav a{margin-left:22px;font-weight:600;font-size:14px;color:var(--muted);}
.site-header nav a:hover{color:var(--ink);text-decoration:none;}

/* article */
.article{max-width:760px;margin:0 auto;padding:40px 20px 56px;}
.crumb{font-size:13px;color:var(--muted);margin-bottom:18px;}
.cat{display:inline-block;font-size:12px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--teal);background:rgba(44,191,146,.1);border:1px solid rgba(44,191,146,.2);padding:4px 12px;border-radius:999px;margin:0 0 14px;}
.article h1{font-size:clamp(30px,5vw,44px);line-height:1.12;letter-spacing:-.02em;margin:0 0 12px;font-weight:800;}
.meta{color:var(--muted);font-size:14px;margin:0 0 30px;padding-bottom:24px;border-bottom:1px solid var(--line);}
.prose{font-size:18px;}
.prose h2{font-size:26px;font-weight:800;letter-spacing:-.01em;margin:40px 0 12px;}
.prose h3{font-size:20px;font-weight:700;margin:28px 0 8px;}
.prose p{margin:0 0 18px;}
.prose ul,.prose ol{margin:0 0 18px;padding-left:24px;}
.prose li{margin:7px 0;}
.prose code{background:#eef1f5;border:1px solid var(--line);border-radius:6px;padding:1px 6px;font-family:ui-monospace,Menlo,Consolas,monospace;font-size:.86em;}
.prose pre{background:#0f172a;color:#e2e8f0;border-radius:14px;padding:18px 20px;overflow:auto;font-size:14px;line-height:1.6;margin:0 0 20px;}
.prose pre code{background:none;border:none;padding:0;color:inherit;}
.prose blockquote{margin:0 0 20px;padding:14px 20px;background:var(--paper);border-left:4px solid var(--teal);border-radius:0 12px 12px 0;color:#334155;}
.prose strong{color:var(--ink);}
.prose table{width:100%;border-collapse:collapse;margin:0 0 20px;font-size:15px;}
.prose th,.prose td{border:1px solid var(--line);padding:10px 12px;text-align:left;}
.prose th{background:#f1f5f9;font-weight:700;}
.cta-tool{margin:36px 0;background:linear-gradient(135deg,rgba(44,191,146,.08),rgba(98,146,217,.08));border:1px solid var(--line);border-radius:18px;padding:22px 24px;display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;}
.cta-tool .t{font-weight:700;color:var(--ink);}
.cta-tool .t span{display:block;font-weight:500;color:var(--muted);font-size:14px;}
.cta-tool a.btn{background:linear-gradient(135deg,#2cbf92,#6292d9);color:#fff;font-weight:700;padding:12px 22px;border-radius:12px;white-space:nowrap;}
.cta-tool a.btn:hover{text-decoration:none;opacity:.95;}

/* related */
.related{max-width:760px;margin:0 auto;padding:0 20px 60px;}
.related h2{font-size:20px;margin:0 0 16px;}
.rgrid{display:grid;gap:14px;grid-template-columns:1fr 1fr;}
.rcard{background:var(--paper);border:1px solid var(--line);border-radius:14px;padding:18px;display:block;}
.rcard:hover{text-decoration:none;border-color:rgba(44,191,146,.35);}
.rcard .rc{font-size:11px;font-weight:800;text-transform:uppercase;letter-spacing:.06em;color:var(--teal);}
.rcard h3{margin:6px 0 0;font-size:16px;color:var(--ink);font-weight:700;line-height:1.3;}

/* index */
.hero{text-align:center;padding:56px 0 24px;}
.hero h1{font-size:clamp(32px,5vw,48px);font-weight:900;letter-spacing:-.02em;margin:0 0 10px;}
.hero p{color:var(--muted);font-size:18px;max-width:54ch;margin:0 auto;}
.grid{display:grid;gap:20px;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));padding:22px 0 72px;}
.card{background:var(--paper);border:1px solid var(--line);border-radius:18px;padding:24px;display:flex;flex-direction:column;transition:transform .25s,box-shadow .25s,border-color .25s;}
.card:hover{transform:translateY(-4px);box-shadow:0 20px 40px -22px rgba(15,23,42,.25);border-color:rgba(44,191,146,.3);text-decoration:none;}
.card .cat{margin-bottom:12px;}
.card h2{font-size:19px;font-weight:700;color:var(--ink);margin:0 0 8px;line-height:1.3;}
.card p{color:var(--muted);font-size:14.5px;margin:0 0 16px;flex-grow:1;}
.card .more{font-weight:700;font-size:13px;color:var(--teal);}

/* footer */
.site-footer{border-top:1px solid var(--line);background:#fff;padding:30px 0 44px;text-align:center;color:var(--muted);font-size:13px;}
.site-footer a{color:var(--muted);margin:0 8px;}
.site-footer .credit{margin-top:8px;color:#94a3b8;}
.site-footer .credit b{color:#64748b;font-weight:600;}

@media(max-width:620px){
  .rgrid{grid-template-columns:1fr;}
  .site-header nav a.hide-sm{display:none;}
  .article{padding-top:28px;}
  .prose{font-size:17px;}
  .cta-tool{flex-direction:column;align-items:flex-start;}
}