*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{--accent:#0891b2;--ink:#164e63;--muted:#64748b;--line:#a5f3fc;--bg:#ecfeff;--max:960px;--soft:#f0fdfa;--radius:12px}
html{scroll-behavior:smooth;scroll-padding-top:72px}
body{font-family:"Noto Sans SC",system-ui,sans-serif;background:linear-gradient(160deg,#ecfeff 0%,#f0fdfa 50%,#ecfeff 100%);color:var(--ink);line-height:1.82;font-size:16px;min-height:100vh}
img{max-width:100%;height:auto;display:block}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.container{max-width:var(--max);margin:0 auto;padding:0 1.25rem}
.site-header{border-bottom:1px solid var(--line);background:rgba(255,255,255,.92);backdrop-filter:blur(8px);position:sticky;top:0;z-index:100}
.header-row{display:flex;align-items:center;justify-content:space-between;min-height:58px;gap:1rem;position:relative}
.brand{display:flex;align-items:center;gap:.6rem;color:var(--ink);font-size:.95rem;font-weight:600;text-decoration:none}
.brand b{color:var(--accent)}
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:1px solid var(--line);border-radius:8px;cursor:pointer;padding:8px;width:40px;height:40px;justify-content:center;align-items:center}
.nav-toggle span{display:block;width:20px;height:2px;background:var(--ink)}
.site-nav ul{display:flex;gap:1.25rem;list-style:none;flex-wrap:wrap}
.site-nav a{color:var(--muted);font-size:.9rem;text-decoration:none}
.site-nav a.active,.site-nav a:hover{color:var(--accent)}
.ads-top-bar{background:#f0fdfa;border-bottom:1px solid var(--line);padding:.5rem 0}
.applist-title{font-size:.8rem;color:var(--accent);font-weight:600;margin-bottom:.35rem;text-align:center}
#ads{display:flex;justify-content:center;flex-wrap:wrap;gap:.5rem}
.hero{padding:2rem 0 1rem;border-bottom:1px solid var(--line)}
.hero h1{font-size:clamp(1.35rem,3vw,1.85rem);line-height:1.35;margin-bottom:1rem;color:var(--ink)}
.lead{color:#334155;font-size:1.02rem;margin-bottom:.75rem;text-align:justify}
.lead strong{color:var(--ink)}
.link-strip{display:flex;flex-wrap:wrap;gap:.75rem;padding:1.25rem 0;border-bottom:1px solid var(--line)}
.link-strip a{padding:.45rem 1rem;border:1px solid var(--line);border-radius:999px;font-size:.85rem;color:var(--accent);background:#fff}
.link-strip a:hover{background:var(--accent);color:#fff;text-decoration:none;border-color:var(--accent)}
.offset-stack{padding:2rem 0 1rem}
.offset-block{margin-bottom:1.75rem;max-width:92%}
.offset-block:nth-child(odd){margin-left:0}
.offset-block:nth-child(even){margin-left:6%}
.offset-block:nth-child(3n){margin-left:3%}
.block-inner{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1.5rem 1.75rem;box-shadow:0 6px 24px rgba(8,145,178,.08);border-left:4px solid var(--accent);position:relative}
.block-num{display:inline-block;font-size:.75rem;font-weight:700;color:var(--accent);background:var(--soft);padding:.2rem .55rem;border-radius:4px;margin-bottom:.65rem;letter-spacing:.05em}
.offset-block h2{font-size:1.12rem;color:var(--accent);margin-bottom:.75rem;line-height:1.4}
.offset-block p{margin-bottom:.8rem;text-align:justify;color:#334155;font-size:.96rem}
.content-fig img{width:100%;max-width:560px;margin:1rem auto;border-radius:8px;border:1px solid var(--line)}
.content-fig figcaption{font-size:.78rem;color:var(--muted);margin-top:.45rem;text-align:center}
.faq{margin:2rem 0;padding-top:1.5rem;border-top:1px solid var(--line)}
.faq h2{font-size:1.2rem;margin-bottom:1rem;color:var(--accent)}
.faq details{border:1px solid var(--line);border-radius:var(--radius);margin-bottom:.5rem;background:#fff}
.faq summary{cursor:pointer;padding:.75rem 1rem;font-weight:600;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq details[open] summary{border-bottom:1px solid var(--line)}
.faq details p{padding:.75rem 1rem;font-size:.92rem;color:var(--muted)}
.related-read{padding:2rem 0 3rem;border-top:1px solid var(--line)}
.related-read h2{font-size:1rem;margin-bottom:1rem;color:var(--accent)}
.related-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:.75rem}
.related-grid a{display:block;padding:.65rem;border:1px solid var(--line);border-radius:6px;text-align:center;font-size:.88rem;color:var(--ink);text-decoration:none;background:#fff}
.related-grid a:hover{border-color:var(--accent);color:var(--accent)}
.site-footer{border-top:1px solid var(--line);padding:1.5rem 0 2rem;background:rgba(255,255,255,.7)}
.footer-links{display:flex;flex-wrap:wrap;gap:1rem;margin-bottom:.75rem;justify-content:center}
.footer-links a{font-size:.85rem;color:var(--muted);text-decoration:none}
.site-footer p{font-size:.8rem;color:var(--muted);text-align:center}
.page-head{padding:2rem 0 1rem;border-bottom:1px solid var(--line)}
.page-head h1{font-size:1.6rem;color:var(--ink)}
.breadcrumb{font-size:.85rem;color:var(--muted);margin-bottom:.75rem}
.breadcrumb a{color:var(--muted)}
.prose-page{padding:2rem 0 3rem;max-width:720px}
.prose-page h2{font-size:1.15rem;margin:1.5rem 0 .75rem;color:var(--accent)}
.prose-page p{margin-bottom:1rem;text-align:justify;color:#334155}
.error-page{min-height:55vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:2rem}
.error-page h1{font-size:3rem;color:var(--accent)}
@media(max-width:768px){
  .nav-toggle{display:flex}
  .site-nav{position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);padding:1rem;display:none}
  .site-nav.is-open{display:block}
  .site-nav ul{flex-direction:column;gap:.75rem}
  .offset-block,.offset-block:nth-child(odd),.offset-block:nth-child(even),.offset-block:nth-child(3n){margin-left:0;max-width:100%}
}