:root{--blue:#1d4ed8;--blue-dark:#1e3a8a;--blue-soft:#eff6ff;--ink:#0f172a;--muted:#64748b;--bg:#f8fafc;--card:#ffffff;--line:#e2e8f0;--radius:16px;--shadow:0 1px 2px rgba(15,23,42,.05),0 8px 24px -12px rgba(15,23,42,.18)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--ink);margin:0;line-height:1.7;-webkit-font-smoothing:antialiased}a{color:var(--blue);text-decoration:none}a:hover{text-decoration:underline}img{max-width:100%}.site-header{position:sticky;top:0;z-index:50;background:#ffffffeb;backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}.header-in{max-width:1080px;margin:0 auto;padding:0 20px;height:64px;display:flex;align-items:center;gap:16px}.logo{font-size:22px;font-weight:800;color:var(--ink);letter-spacing:-.02em}.logo span{color:var(--blue)}.logo:hover{text-decoration:none}.main-nav{margin-left:auto;display:flex;gap:22px;align-items:center}.main-nav a{color:var(--ink);font-weight:600;font-size:15px}.main-nav a:hover{color:var(--blue);text-decoration:none}.nav-toggle{display:none;margin-left:auto}.nav-toggle summary{list-style:none;cursor:pointer;font-size:24px;line-height:1;padding:8px;color:var(--ink)}.nav-toggle summary::-webkit-details-marker{display:none}@media(max-width:640px){.main-nav{display:none}.nav-toggle{display:block;position:relative}.nav-toggle .main-nav{display:flex;position:absolute;right:0;top:44px;background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:var(--shadow);flex-direction:column;align-items:stretch;gap:0;padding:8px;min-width:180px}.nav-toggle .main-nav a{padding:10px 12px;border-radius:8px}.nav-toggle .main-nav a:hover{background:var(--blue-soft)}}.wrap{max-width:1080px;margin:0 auto;padding:0 20px}.ad-slot{background:#eef2f7;border:1px dashed #b6c2d2;border-radius:12px;display:flex;align-items:center;justify-content:center;color:#7c8aa0;font-size:13px;margin:22px 0}.ad-leaderboard{height:90px}.ad-inarticle{height:250px}.hero{padding:44px 0 8px;text-align:left}.hero .eyebrow{display:inline-block;background:var(--blue-soft);color:var(--blue);font-weight:700;font-size:13px;padding:5px 12px;border-radius:999px;letter-spacing:.02em}.hero h1{font-size:clamp(30px,5vw,44px);line-height:1.15;letter-spacing:-.02em;margin:16px 0 10px}.hero p{color:var(--muted);font-size:17px;max-width:640px;margin:0}.chips{display:flex;gap:8px;flex-wrap:wrap;margin:26px 0 6px}.chip{border:1px solid var(--line);background:#fff;color:var(--ink);font-size:14px;font-weight:600;padding:7px 14px;border-radius:999px;cursor:pointer}.chip:hover{border-color:var(--blue);color:var(--blue)}.chip.active{background:var(--blue);border-color:var(--blue);color:#fff}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;padding:22px 0 10px}@media(max-width:900px){.grid{grid-template-columns:repeat(2,1fr)}}@media(max-width:600px){.grid{grid-template-columns:1fr}}.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);display:flex;flex-direction:column;position:relative;transition:transform .15s ease,box-shadow .15s ease}.card:hover{transform:translateY(-3px)}.card .cover{aspect-ratio:16/9;display:flex;align-items:center;justify-content:center;color:#fff;font-size:44px;font-weight:800;letter-spacing:-.02em;position:relative;overflow:hidden}.card .cover img{width:100%;height:100%;object-fit:cover;position:absolute;inset:0}.g1{background:linear-gradient(135deg,#1d4ed8,#38bdf8)}.g2{background:linear-gradient(135deg,#7c3aed,#ec4899)}.g3{background:linear-gradient(135deg,#059669,#84cc16)}.g4{background:linear-gradient(135deg,#ea580c,#f59e0b)}.card 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.hero-img{border-radius:var(--radius);margin:6px 0 22px}.prose{font-size:17px}.prose h2{font-size:25px;letter-spacing:-.01em;margin:34px 0 10px}.prose h3{font-size:20px;margin:26px 0 8px}.prose p{margin:0 0 16px}.prose img{border-radius:12px}.prose ul,.prose ol{margin:0 0 16px;padding-left:22px}.prose li{margin-bottom:6px}.prose code{background:#eef2f7;border-radius:6px;padding:1px 6px;font-size:.92em}.share{border-top:1px solid var(--line);margin-top:30px;padding-top:20px}.share h2{font-size:18px;margin:0 0 12px}.share .row{display:flex;gap:10px;flex-wrap:wrap}.share a{border:1px solid var(--line);background:#fff;border-radius:999px;padding:8px 16px;font-weight:600;font-size:14px;color:var(--ink)}.share a:hover{border-color:var(--blue);color:var(--blue);text-decoration:none}.page{max-width:760px;margin:0 auto;padding:34px 0 8px}.page h1{font-size:clamp(28px,4.5vw,38px);letter-spacing:-.02em;margin:0 0 14px}.site-footer{border-top:1px solid var(--line);background:#fff;margin-top:48px}.footer-in{max-width:1080px;margin:0 auto;padding:34px 20px 22px;display:grid;grid-template-columns:2fr 1fr 1fr;gap:28px}@media(max-width:700px){.footer-in{grid-template-columns:1fr}}.site-footer h3{font-size:15px;margin:0 0 12px}.site-footer a{display:block;color:var(--muted);font-size:14px;padding:3px 0}.site-footer a:hover{color:var(--blue)}.site-footer .about{color:var(--muted);font-size:14px;max-width:340px}.footer-bar{border-top:1px solid var(--line);padding:14px 20px;text-align:center;color:var(--muted);font-size:13px}