*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
body{font-family:"Noto Sans SC",system-ui,sans-serif;background:#fff;color:#1a1a1a;line-height:1.78;font-size:16px}
a{color:#4f46e5;text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto;display:block}

.site-header{background:#fff;border-bottom:1px solid #e5e7eb;position:sticky;top:0;z-index:200}
.header-inner{max-width:1160px;margin:0 auto;padding:12px 20px;display:flex;align-items:center;justify-content:space-between;gap:16px}
.brand{display:flex;align-items:center;gap:10px;color:#111;font-weight:600;font-size:.98rem}
.brand:hover{text-decoration:none}
.brand img{border-radius:8px}
.brand em{font-style:normal;color:#4f46e5;font-weight:700}
.site-nav ul{display:flex;flex-wrap:wrap;gap:6px 18px;list-style:none}
.site-nav a{color:#555;font-size:.9rem;padding:4px 0}
.site-nav a.active{color:#4f46e5;font-weight:600;border-bottom:2px solid #4f46e5}
.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px;flex-direction:column;gap:5px}
.nav-toggle span{display:block;width:22px;height:2px;background:#333;transition:.2s}
.nav-toggle.is-open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle.is-open span:nth-child(2){opacity:0}
.nav-toggle.is-open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

.ads-top-bar{background:#eef2ff;border-bottom:1px solid #c7d2fe;padding:10px 0}
.applist-title{font-size:.78rem;color:#888;text-align:center;margin-bottom:6px}
#ads{display:flex;justify-content:center;flex-wrap:wrap;gap:12px}
#ads .caption{font-size:.7rem;color:#666;margin-top:4px;text-align:center;max-width:70px;line-height:1.3}

.shell{max-width:1160px;margin:0 auto;padding:0 20px}

.hero-minimal{padding:34px 0 24px;border-bottom:3px double #e0e7ff}
.hero-minimal .tag{display:inline-block;background:#4f46e5;color:#fff;font-size:.76rem;font-weight:600;padding:4px 12px;border-radius:4px;margin-bottom:12px;letter-spacing:.06em}
.hero-minimal h1{font-size:1.76rem;line-height:1.34;margin-bottom:12px;max-width:780px}
.hero-minimal .lede{color:#374151;font-size:1.01rem;max-width:780px;margin-bottom:8px}

.stat-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;padding:22px 0;border-bottom:1px solid #e5e7eb}
.stat-box{background:#f8fafc;border:1px solid #e2e8f0;border-radius:10px;padding:14px 16px;text-align:center}
.stat-box strong{display:block;font-size:1.1rem;color:#4f46e5;margin-bottom:4px}
.stat-box span{font-size:.78rem;color:#64748b;line-height:1.45}

.body-grid{display:grid;grid-template-columns:220px 1fr;gap:32px;padding:28px 0 40px;align-items:start}
.toc-side{position:sticky;top:72px}
.toc-side h2{font-size:.85rem;color:#64748b;text-transform:uppercase;letter-spacing:.08em;margin-bottom:12px}
.toc-side ol{list-style:none;counter-reset:toc}
.toc-side li{counter-increment:toc;margin-bottom:6px}
.toc-side a{display:block;font-size:.88rem;color:#475569;padding:8px 12px;border-radius:8px;border-left:3px solid transparent;transition:.15s}
.toc-side a:hover,.toc-side a.is-active{background:#eef2ff;border-left-color:#4f46e5;color:#4f46e5;text-decoration:none;font-weight:600}

.prose-flow{min-width:0}
.prose-flow section{margin-bottom:36px;scroll-margin-top:88px}
.prose-flow h2{font-size:1.24rem;color:#111;margin-bottom:12px}
.prose-flow p{color:#374151;margin-bottom:12px;font-size:.98rem}
.inset-quote{background:#f5f3ff;border-left:4px solid #7c3aed;padding:14px 18px;margin:16px 0;border-radius:0 8px 8px 0;font-size:.93rem;color:#4c1d95}
.prose-flow figure{margin:18px 0;border-radius:12px;overflow:hidden;border:1px solid #e5e7eb}
.prose-flow figcaption{font-size:.8rem;color:#64748b;padding:10px 12px;background:#f8fafc}

.photo-strip{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:20px 0}
.photo-strip figure{border-radius:10px;overflow:hidden;border:1px solid #e5e7eb;margin:0}
.photo-strip figcaption{font-size:.72rem;padding:8px}

.faq-stack{display:flex;flex-direction:column;gap:12px;margin-top:8px}
.faq-stack details{background:#fff;border:1px solid #e2e8f0;border-radius:10px;padding:0 16px}
.faq-stack summary{cursor:pointer;font-weight:600;color:#4f46e5;padding:14px 0;font-size:.94rem;list-style:none}
.faq-stack summary::-webkit-details-marker{display:none}
.faq-stack details[open] summary{border-bottom:1px solid #e2e8f0;margin-bottom:10px}
.faq-stack details p{padding-bottom:14px;font-size:.9rem;color:#475569}

.end-note{background:linear-gradient(135deg,#eef2ff,#fff);border:1px solid #c7d2fe;border-radius:14px;padding:22px 24px;margin-top:8px}
.end-note h2{font-size:1.12rem;margin-bottom:10px}
.read-more{display:flex;flex-wrap:wrap;gap:12px 18px;margin-top:16px;font-size:.86rem}

.site-footer{background:#f8fafc;border-top:1px solid #e5e7eb;padding:28px 20px;text-align:center}
.footer-links{display:flex;flex-wrap:wrap;justify-content:center;gap:8px 20px;margin-bottom:10px;font-size:.88rem}
.site-footer p{font-size:.82rem;color:#888}
.prose-page{max-width:760px;margin:0 auto;padding:32px 20px 48px}
.prose-page h1{font-size:1.6rem;margin-bottom:16px}
.prose-page p{margin-bottom:12px;color:#374151}
.error-page{text-align:center;padding:80px 20px}
.error-page h1{font-size:3rem;color:#4f46e5}

@media(max-width:900px){
  .stat-strip{grid-template-columns:repeat(2,1fr)}
  .body-grid{grid-template-columns:1fr}
  .toc-side{position:static;display:flex;flex-wrap:wrap;gap:8px}
  .toc-side h2{width:100%}
  .toc-side ol{display:flex;flex-wrap:wrap;gap:6px}
  .photo-strip{grid-template-columns:1fr}
}
@media(max-width:768px){
  .nav-toggle{display:flex}
  .site-nav{position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid #e5e7eb;padding:12px 20px;display:none;box-shadow:0 8px 24px rgba(0,0,0,.06)}
  .site-nav.is-open{display:block}
  .site-nav ul{flex-direction:column;gap:10px}
  .site-header{position:relative}
}