*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{--bg:#fff;--ink:#1a1a1a;--muted:#555;--line:#e5e5e5;--accent:#7c3aed;--accent-soft:#7c3aed18;--max:1140px;--radius:10px}
html{scroll-behavior:smooth;scroll-padding-top:72px}
body{font-family:"Noto Sans SC",system-ui,sans-serif;background:var(--bg);color:var(--ink);line-height:1.82;font-size:16px}
img{max-width:100%;height:auto;display:block}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.container{width:min(100% - 2rem,var(--max));margin-inline:auto}
.site-header{position:sticky;top:0;z-index:100;background:#fff;border-bottom:1px solid var(--line)}
.header-row{display:flex;align-items:center;justify-content:space-between;min-height:64px;gap:1rem}
.brand{display:flex;align-items:center;gap:.6rem;font-weight:600;color:var(--ink)}
.brand img{border-radius:8px}
.site-nav ul{display:flex;gap:1rem;list-style:none;flex-wrap:wrap}
.site-nav a{color:var(--muted);font-size:.95rem;padding:.25rem 0;border-bottom:2px solid transparent}
.site-nav a.active,.site-nav a:hover{color:var(--accent);border-bottom-color:var(--accent)}
.nav-toggle{display:none;background:none;border:1px solid var(--line);width:42px;height:42px;border-radius:8px;cursor:pointer}
.nav-toggle span{display:block;height:2px;background:var(--ink);margin:6px}
.ads-top-bar{border-bottom:1px solid var(--line);background:#fafafa;padding:.5rem 0}
.applist-title{font-size:.78rem;color:var(--muted);text-align:center;margin-bottom:.35rem}
#ads{display:flex;justify-content:center;flex-wrap:wrap;gap:.5rem}
.ads-item figure{margin:0;text-align:center}
.ads-item img{width:65px;height:65px;border-radius:12px;object-fit:cover}
.ads-item .caption{font-size:11px;color:var(--muted);max-width:76px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.ext-links{display:flex;flex-wrap:wrap;gap:.75rem;padding:1rem 0;border-bottom:1px solid var(--line)}
.ext-links a{padding:.45rem .9rem;border:1px solid var(--line);border-radius:999px;font-size:.88rem;color:var(--ink);background:#fff}
.ext-links a:hover{border-color:var(--accent);color:var(--accent);text-decoration:none}
.hero-wrap{padding:2rem 0 1rem;border-bottom:1px solid var(--line)}
.hero-inner h1{font-size:clamp(1.5rem,3.5vw,2.1rem);line-height:1.35;margin-bottom:1rem}
.lead{color:#333;font-size:1.05rem;margin-bottom:1.25rem}
.hero-img img{border-radius:var(--radius);box-shadow:0 8px 24px rgba(0,0,0,.08)}
.content-block{margin:2rem 0;padding-bottom:1.5rem;border-bottom:1px dashed var(--line)}
.content-block h2{font-size:1.25rem;color:var(--accent);margin-bottom:1rem}
.content-block p{margin-bottom:1rem;text-align:justify}
.inline-fig{margin:1rem 0}
.tip-box{background:var(--accent-soft);border-left:4px solid var(--accent);padding:1rem 1.2rem;border-radius:0 var(--radius) var(--radius) 0;margin-top:1rem}
.faq-block{padding:2rem 0 3rem}
.faq-block h2{margin-bottom:1rem}
.faq-block details{border:1px solid var(--line);border-radius:var(--radius);padding:1rem;margin-bottom:.75rem;background:#fafafa}
.faq-block summary{cursor:pointer;font-weight:600}
.page-hero{padding:2rem 0 1rem;border-bottom:1px solid var(--line)}
.breadcrumb{font-size:.86rem;color:var(--muted);margin-bottom:.5rem}
.prose-wrap{padding:2rem 0 3rem}
.prose-section{margin-bottom:2rem}
.prose-section h2{color:var(--accent);margin-bottom:1rem}
.prose-section p{margin-bottom:1rem;text-align:justify}
.related-read{margin-top:2rem;padding:1.5rem;border:1px solid var(--line);border-radius:var(--radius);background:#fafafa}
.related-read ul{list-style:none;display:grid;gap:.5rem}
.site-footer{border-top:1px solid var(--line);padding:2rem 0;text-align:center;color:var(--muted);font-size:.88rem}
.footer-links{display:flex;flex-wrap:wrap;justify-content:center;gap:1rem;margin-bottom:.75rem}
.footer-links a{color:var(--muted)}
.error-wrap{padding:3rem 0;min-height:50vh}
.error-wrap .code{font-size:4rem;font-weight:700;color:var(--accent);line-height:1}
.error-wrap h1{margin:1rem 0}
@media(max-width:768px){
  .nav-toggle{display:block}
  .site-nav{display:none;position:absolute;top:64px;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);padding:1rem}
  .site-nav.open{display:block}
  .site-nav ul{flex-direction:column}
}

.main-body.layout-narrow{max-width:680px;margin-inline:auto}
.main-body.layout-narrow .content-block{border-bottom:none}
.main-body.layout-narrow .content-block p{font-size:1.05rem;line-height:2}
.main-body.layout-narrow .content-block h2{text-align:center;border-bottom:2px solid var(--accent);padding-bottom:.5rem}