:root{color-scheme:light;--background:#f5f7fb;--surface:#fff;--text:#172033;--muted:#687187;--line:#e6eaf1;--accent:#315efb;--accent-soft:#eef2ff;--warning:#9a5b00;--warning-bg:#fff7e8}
*{box-sizing:border-box}
html{background:var(--background)}
body{margin:0;min-height:100vh;min-height:100dvh;color:var(--text);background:var(--background);font-family:-apple-system,BlinkMacSystemFont,"SF Pro Text","PingFang SC","Helvetica Neue",sans-serif;-webkit-font-smoothing:antialiased;-webkit-text-size-adjust:100%}
a{color:inherit;-webkit-tap-highlight-color:transparent}
.shell{width:min(100%,680px);margin:0 auto;padding:calc(20px + env(safe-area-inset-top)) 18px calc(32px + env(safe-area-inset-bottom))}
.top{display:flex;min-height:36px;align-items:center;justify-content:space-between;margin-bottom:24px}
.brand{font-size:15px;font-weight:700;text-decoration:none}
.back{color:var(--accent);font-size:14px;text-decoration:none}
.hero,.document{border:1px solid var(--line);border-radius:20px;background:var(--surface);box-shadow:0 10px 32px rgba(28,42,72,.06)}
.hero{padding:26px 22px}
.hero h1,.document h1{margin:0;font-size:27px;line-height:1.3;letter-spacing:-.02em}
.hero>p{margin:10px 0 0;color:var(--muted);font-size:14px;line-height:1.7}
.warning{margin-top:20px;padding:13px 14px;border-radius:12px;color:var(--warning);background:var(--warning-bg);font-size:13px;line-height:1.65}
.toc{display:grid;gap:10px;margin-top:16px}
.toc a{display:flex;min-height:54px;align-items:center;justify-content:space-between;padding:0 17px;border:1px solid var(--line);border-radius:15px;background:var(--surface);font-size:15px;font-weight:600;text-decoration:none}
.toc a::after{content:"›";color:#9aa3b5;font-size:23px;font-weight:400}
.toc a:active{background:#f8f9fc;transform:scale(.995)}
.document{padding:25px 22px}
.document .summary{margin:9px 0 24px;color:var(--muted);font-size:13px}
.document h2,.document h3{margin:26px 0 10px;font-size:17px;line-height:1.5}
.document p,.document li{color:#4f5a70;font-size:15px;line-height:1.85}
.document p{margin:12px 0}
.document ul,.document ol{margin:12px 0;padding-left:21px}
.placeholder{color:#c23b3b;background:#fff0f0}
.note{margin-top:22px;padding:14px;border-radius:13px;color:var(--muted);background:var(--accent-soft);font-size:13px;line-height:1.7}
.meta{margin:8px 0 22px!important;color:var(--muted)!important;font-size:12px!important}
.document a{color:var(--accent);text-underline-offset:3px}
.table-wrap{max-width:100%;margin:16px 0;overflow-x:auto;border:1px solid var(--line);border-radius:12px;-webkit-overflow-scrolling:touch}
table{width:100%;min-width:560px;border-collapse:collapse;background:var(--surface);font-size:13px}
th,td{padding:12px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top;line-height:1.65}
th{color:var(--text);background:var(--accent-soft);font-weight:700}
td{color:var(--muted)}
tbody tr:last-child td{border-bottom:0}

/* 帮助中心 */
.help-page{padding:0;border:0;background:transparent;box-shadow:none}
.help-hero{position:relative;overflow:hidden;padding:26px 22px;border-radius:20px;color:#fff;background:linear-gradient(135deg,#ff4f86 0%,#ff285d 58%,#ff623d 100%);box-shadow:0 14px 34px rgba(255,40,93,.2)}
.help-hero::after{content:"?";position:absolute;right:18px;bottom:-35px;color:rgba(255,255,255,.13);font-size:130px;font-weight:800;line-height:1}
.help-eyebrow{display:inline-flex;padding:5px 10px;border:1px solid rgba(255,255,255,.35);border-radius:999px;background:rgba(255,255,255,.14);font-size:12px;font-weight:600}
.help-hero h1{position:relative;z-index:1;margin-top:15px;font-size:28px}
.help-hero p{position:relative;z-index:1;max-width:430px;margin:8px 0 0;color:rgba(255,255,255,.88);font-size:14px;line-height:1.7}
.help-shortcuts{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin:14px 0 24px;padding:14px;border:1px solid var(--line);border-radius:18px;background:var(--surface);box-shadow:0 8px 28px rgba(28,42,72,.05)}
.help-shortcuts a{display:flex;min-width:0;align-items:center;flex-direction:column;gap:8px;color:var(--muted);font-size:12px;text-decoration:none}
.help-shortcut-icon{display:grid;width:38px;height:38px;place-items:center;border-radius:13px;color:#ff285d;background:#fff0f5;font-size:14px;font-weight:800}
.help-section{margin:0 0 16px;padding:8px 18px;border:1px solid var(--line);border-radius:18px;background:var(--surface);box-shadow:0 8px 28px rgba(28,42,72,.04);scroll-margin-top:16px}
.help-section h2{display:flex;align-items:center;gap:9px;margin:10px 0 4px;color:var(--text);font-size:17px}
.help-section h2 span{display:grid;width:29px;height:29px;place-items:center;border-radius:9px;color:#ff285d;background:#fff0f5;font-size:11px;font-weight:800}
.help-section details{border-top:1px solid var(--line)}
.help-section h2+details{border-top:0}
.help-section summary{position:relative;padding:17px 26px 17px 0;color:var(--text);font-size:15px;font-weight:600;line-height:1.5;cursor:pointer;list-style:none;-webkit-tap-highlight-color:transparent}
.help-section summary::-webkit-details-marker{display:none}
.help-section summary::after{content:"+";position:absolute;top:15px;right:1px;color:#9aa3b5;font-size:21px;font-weight:300;transition:transform .2s ease}
.help-section details[open] summary::after{transform:rotate(45deg)}
.help-section details p{margin:-4px 0 17px;padding-right:8px;color:var(--muted);font-size:14px;line-height:1.8}
.help-contact{margin-top:22px;padding:22px;border-radius:20px;color:#fff;background:linear-gradient(145deg,#283247,#172033)}
.help-contact h2{margin:0;font-size:19px}
.help-contact p{margin:8px 0 17px;color:rgba(255,255,255,.72);font-size:13px;line-height:1.7}
.help-contact a{display:flex;min-height:46px;align-items:center;justify-content:center;border-radius:999px;color:#fff;background:linear-gradient(90deg,#ff4f86,#ff285d);font-size:14px;font-weight:700;text-decoration:none}
.help-contact small{display:block;margin-top:10px;color:rgba(255,255,255,.55);font-size:11px;text-align:center}

/* App WebView：页面导航由原生导航栏承载，正文采用接近原生设置页的布局。 */
@media(max-width:720px){
  .shell{padding:calc(14px + env(safe-area-inset-top)) 18px calc(28px + env(safe-area-inset-bottom))}
  .top{display:none}
  .hero,.document{border:0;border-radius:0;box-shadow:none}
  .hero{padding:12px 2px 18px;background:transparent}
  .document{padding:4px 2px;background:transparent}
  .hero h1,.document h1{font-size:25px}
  .document h2,.document h3{scroll-margin-top:16px}
  .toc{margin-top:8px}
  .toc a{min-height:56px;border-radius:13px}
  .warning{margin-top:16px}
  .table-wrap{margin-right:-18px;margin-left:-2px;border-right:0;border-radius:12px 0 0 12px}
  .help-shell{padding-top:calc(12px + env(safe-area-inset-top));padding-right:14px;padding-left:14px}
  .help-page{padding:0}
  .help-hero{padding:23px 20px;border-radius:18px}
  .help-shortcuts{gap:5px;padding:13px 7px}
  .help-section{padding-right:16px;padding-left:16px}
}
@media(prefers-color-scheme:dark){:root{--background:#11141b;--surface:#1b1f28;--text:#f3f5fa;--muted:#a1a9b9;--line:#2c323e;--accent:#7da0ff;--accent-soft:#202b47;--warning:#efbd72;--warning-bg:#342919}
.document p,.document li{color:#c5cad4}
.toc a:active{background:#232832}
.placeholder{color:#ff9d9d;background:#3b2225}
.help-shortcut-icon,.help-section h2 span{color:#ff739c;background:#34202a}
}