:root{
  --brand:#2b6cb0; --brand-d:#215688; --accent:#f5893b; --accent-d:#e0742a;
  --ink:#20262e; --muted:#7f8894; --line:#e6e9ee; --bg:#f4f6f9; --card:#fff;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font-family:-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;background:var(--bg);color:var(--ink);line-height:1.6}
a{color:inherit;text-decoration:none}
.topbar{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.topbar-in{max-width:1120px;margin:0 auto;padding:0 20px;height:56px;display:flex;align-items:center;justify-content:space-between}
.logo{display:flex;align-items:center;gap:10px}
.logo-mark{width:32px;height:32px;border-radius:9px;background:linear-gradient(135deg,var(--brand),#4a90d9);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:700}
.logo-tx b{display:block;font-size:15px;line-height:1.1}
.logo-tx em{font-style:normal;font-size:11px;color:var(--muted)}
.nav{display:flex;gap:4px;flex-wrap:wrap}
.nav a{padding:7px 12px;border-radius:8px;font-size:14px;color:#5b616b}
.nav a:hover{background:var(--bg)}
.nav a.active{background:rgba(43,108,176,.1);color:var(--brand-d);font-weight:600}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;height:42px;padding:0 22px;border-radius:9px;border:1px solid var(--line);background:#fff;color:var(--ink);font-size:15px;cursor:pointer;font-family:inherit}
.btn:hover{border-color:var(--brand)}
.btn-primary{background:var(--accent);border-color:var(--accent);color:#fff}
.btn-primary:hover{background:var(--accent-d);border-color:var(--accent-d)}
.sitefoot{max-width:1120px;margin:28px auto 0;padding:22px 20px 40px;color:var(--muted);font-size:13px;border-top:1px solid var(--line);text-align:center}
.sitefoot a{color:#5b616b}.sitefoot .beian{margin-top:6px;font-size:12px}
/* 内容/文章 */
.content{max-width:820px;margin:0 auto;padding:24px 20px}
.content h1{font-size:26px;margin:6px 0 12px}
.content h2{font-size:19px;margin:26px 0 10px}
.content h3{font-size:16px;margin:20px 0 8px}
.content p{margin:10px 0}
.content .lead{color:var(--muted);margin:0 0 16px}
.content ul,.content ol{padding-left:22px}.content li{margin:6px 0}
.crumb{font-size:13px;color:var(--muted);margin-bottom:10px}.crumb a{color:#5b616b}
.linklist{padding-left:0;list-style:none}.linklist li{margin:0 0 10px}
.linklist a{color:var(--brand-d);font-weight:600}
.tip{background:#fff7ee;border:1px solid #ffd9b3;color:#8a5a24;border-radius:10px;padding:12px 14px;font-size:13px;margin:14px 0}
/* 首页工具网格 */
.hero{background:linear-gradient(135deg,#2b6cb0,#1c4e80);color:#fff;border-radius:0}
.hero-in{max-width:1120px;margin:0 auto;padding:34px 20px 30px}
.hero h1{font-size:26px;margin:0 0 8px}
.hero p{margin:0;opacity:.9;font-size:15px}
.section{max-width:1120px;margin:0 auto;padding:26px 20px}
.section>h2{font-size:19px;margin:0 0 14px}
.tools{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:16px}
.tool{background:#fff;border:1px solid var(--line);border-radius:14px;padding:20px;display:block;transition:.15s}
.tool:hover{border-color:var(--brand);transform:translateY(-2px);box-shadow:0 8px 24px rgba(43,108,176,.1)}
.tool .ic{width:44px;height:44px;border-radius:11px;background:rgba(43,108,176,.1);color:var(--brand-d);display:flex;align-items:center;justify-content:center;font-size:22px;margin-bottom:12px}
.tool b{display:block;font-size:16px;margin-bottom:4px}
.tool p{margin:0;color:var(--muted);font-size:13px}
.arts{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:14px}
.art{background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px 18px;display:block}
.art:hover{border-color:var(--brand)}
.art b{display:block;font-size:15px;margin-bottom:4px}
.art span{font-size:13px;color:var(--muted)}
/* 计算器 */
.calc{max-width:760px;margin:0 auto;padding:22px 20px}
.calc h1{font-size:24px;margin:6px 0 6px}
.calc .lead{color:var(--muted);margin:0 0 18px}
.card{background:#fff;border:1px solid var(--line);border-radius:14px;padding:22px 24px}
.fld{margin-bottom:16px}
.fld>label{display:block;font-size:13px;color:#5b616b;margin-bottom:6px}
.fld input[type=number],.fld input[type=text],.fld select{width:100%;border:1px solid var(--line);border-radius:9px;padding:11px 13px;font-size:15px;font-family:inherit;color:var(--ink);background:#fff}
.fld input:focus,.fld select:focus{border-color:var(--brand);outline:none}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.seg{display:flex;flex-wrap:wrap;gap:8px}
.seg button{flex:1;min-width:72px;padding:10px 6px;border:1px solid var(--line);border-radius:9px;background:#fff;font-size:14px;cursor:pointer;color:#5b616b;font-family:inherit}
.seg button.on{background:rgba(43,108,176,.1);border-color:var(--brand);color:var(--brand-d);font-weight:600}
.suffix{position:relative}.suffix input{padding-right:42px}.suffix .u{position:absolute;right:13px;top:50%;transform:translateY(-50%);color:var(--muted);font-size:13px}
/* 结果 */
.result{margin-top:20px;background:#f7fafd;border:1px solid #dce8f3;border-radius:14px;padding:20px 22px}
.result .big{font-size:15px;color:#5b616b}
.result .big b{font-size:30px;color:var(--brand-d);display:block;margin-top:2px}
.result .big b em{font-size:16px;font-style:normal;color:var(--muted);font-weight:400}
.kv{display:flex;justify-content:space-between;padding:9px 0;border-bottom:1px dashed #e2e8f0;font-size:14px}
.kv:last-child{border-bottom:none}.kv span{color:#5b616b}.kv b{color:var(--ink)}
.bars{margin-top:8px}
.bar{margin:9px 0}
.bar .t{display:flex;justify-content:space-between;font-size:13px;margin-bottom:4px;color:#5b616b}
.bar .track{height:9px;background:#e8eef4;border-radius:6px;overflow:hidden}
.bar .fill{height:100%;background:var(--brand);border-radius:6px}
.rowlist .rl{display:grid;grid-template-columns:1fr 1fr 1fr auto;gap:8px;margin-bottom:8px;align-items:center}
.rowlist input{width:100%}
.rowlist .del{border:1px solid var(--line);background:#fff;border-radius:8px;width:34px;height:38px;cursor:pointer;color:#c0392b}
.addrow{border:1px dashed var(--line);background:#fff;border-radius:9px;padding:9px;width:100%;cursor:pointer;color:var(--brand-d);font-size:14px}
.seo{background:#fff;border:1px solid var(--line);border-radius:14px;padding:20px 24px;margin-top:22px}
.seo h2{font-size:16px;margin:18px 0 8px}.seo h2:first-child{margin-top:0}
.seo h3{font-size:14px;margin:14px 0 4px;color:var(--ink)}
.seo p{color:#5b616b;font-size:14px;margin:8px 0}
.seo ul,.seo ol{color:#5b616b;font-size:14px;padding-left:20px;margin:8px 0}.seo li{margin:5px 0}
.faq{border-top:1px dashed var(--line);padding-top:14px;margin-top:14px}
.faq h3{font-size:15px;color:var(--ink);margin:0 0 4px}.faq h3::before{content:"Q ";color:var(--brand-d);font-weight:700}
.faq .a{color:#5b616b;font-size:14px;margin:0 0 14px}
@media(max-width:640px){.grid2{grid-template-columns:1fr}.rowlist .rl{grid-template-columns:1fr 1fr;}}