:root{
  --primary:#2563eb; --primary-d:#1d4ed8; --primary-l:#eff6ff;
  --bg:#f6f8fb; --text:#0f172a; --sub:#64748b; --card:#fff; --line:#e8edf3;
  --radius:14px; --shadow:0 1px 3px rgba(15,23,42,.05); --shadow-lg:0 12px 30px rgba(37,99,235,.12);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--bg);color:var(--text);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:var(--primary);text-decoration:none}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px}

/* 顶栏(对齐 szbs 主站) */
.f-top{background:linear-gradient(120deg,var(--primary-d),var(--primary));color:#fff;position:sticky;top:0;z-index:50;box-shadow:0 4px 20px rgba(37,99,235,.18)}
.f-bar{max-width:1080px;margin:0 auto;display:flex;align-items:center;gap:14px;padding:13px 20px}
.f-logo{font-size:18px;font-weight:800;display:flex;align-items:center;gap:9px;color:#fff}
.f-logo .mark{background:rgba(255,255,255,.2);width:34px;height:34px;border-radius:9px;display:inline-flex;align-items:center;justify-content:center;font-size:18px}
.f-nav{margin-left:auto;display:flex;gap:6px;align-items:center}
.f-nav>a{color:#dbeafe;font-size:14px;font-weight:600;padding:7px 13px;border-radius:9px;transition:.15s}
.f-nav>a:hover{background:rgba(255,255,255,.18);color:#fff}
.f-prod{position:relative}
.f-prod>a{display:flex;align-items:center;gap:4px;color:#dbeafe;font-size:14px;font-weight:600;padding:7px 13px;border-radius:9px}
.f-prod>a:hover{background:rgba(255,255,255,.18);color:#fff}
.f-prod .caret{font-size:9px;opacity:.8}
.f-prod-menu{position:absolute;top:calc(100% + 8px);right:0;background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:0 12px 30px rgba(15,23,42,.16);padding:8px;min-width:184px;display:none;z-index:50}
.f-prod:hover .f-prod-menu{display:block}
.f-prod-menu a{display:flex;align-items:center;gap:9px;color:var(--text);font-size:13.5px;font-weight:500;padding:9px 11px;border-radius:8px}
.f-prod-menu a:hover{background:var(--primary-l);color:var(--primary-d)}
.f-prod-menu .pi{font-size:16px}

/* Hero */
.hero{background:linear-gradient(135deg,var(--primary-d),var(--primary));color:#fff;text-align:center;padding:54px 20px 46px}
.hero h1{font-size:34px;font-weight:800;letter-spacing:1px;margin-bottom:10px}
.hero p{color:#dbeafe;margin-bottom:24px;font-size:15px}
.search{display:flex;max-width:540px;margin:0 auto;background:#fff;border-radius:999px;padding:6px;box-shadow:0 10px 30px rgba(0,0,0,.18)}
.search input{flex:1;border:0;outline:0;padding:11px 20px;font-size:15px;border-radius:999px;color:#1f2937}
.search button{border:0;background:var(--primary);color:#fff;padding:11px 24px;border-radius:999px;font-size:15px;cursor:pointer;font-weight:600}
.search button:hover{background:var(--primary-d)}

/* 分类与卡片 */
.cat{margin:42px 0}
.cat-title{font-size:21px;font-weight:800;color:var(--text);margin-bottom:4px;display:flex;align-items:center;gap:10px}
.cat-title .dot{width:9px;height:18px;border-radius:3px;background:var(--primary)}
.cat-sub{color:var(--sub);font-size:13.5px;margin-bottom:16px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(210px,1fr));gap:14px}
.ccard{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:18px 18px;transition:.2s;display:block;color:var(--text);box-shadow:var(--shadow)}
.ccard:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);border-color:var(--primary)}
.ccard .ico{font-size:26px;margin-bottom:9px}
.ccard h3{font-size:16px;margin-bottom:4px;color:var(--primary-d)}
.ccard p{font-size:12.5px;color:var(--sub);line-height:1.5}

/* footer */
.foot{text-align:center;font-size:12px;color:#94a3b8;padding:30px 16px 40px;line-height:1.9;border-top:1px solid var(--line);margin-top:40px}
.foot a{color:#64748b;margin:0 7px;text-decoration:none}
.foot a:hover{color:var(--primary);text-decoration:underline}
@media(max-width:760px){
  .hero h1{font-size:26px}
  .grid{grid-template-columns:repeat(auto-fill,minmax(150px,1fr))}
  .f-nav>a{display:none}
  .f-prod>a{display:inline-flex}
}

/* ========== 计算器子页面(calc/*) 统一亮蓝规范 ========== */
.topbar{background:linear-gradient(120deg,var(--primary-d),var(--primary));color:#fff;position:sticky;top:0;z-index:50;box-shadow:0 4px 20px rgba(37,99,235,.18)}
.topbar .wrap{display:flex;align-items:center;justify-content:space-between;padding:13px 20px}
.brand{font-size:18px;font-weight:800;color:#fff}
.brand span{opacity:.85;font-weight:600}
.back{color:#dbeafe;font-size:14px;font-weight:600;padding:7px 13px;border-radius:9px;transition:.15s}
.back:hover{background:rgba(255,255,255,.18);color:#fff}

.calc-page{padding:28px 0 10px}
.calc-box{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:26px 24px;max-width:560px;margin:0 auto;box-shadow:var(--shadow)}
.calc-box h2{font-size:22px;font-weight:800;color:var(--primary-d);margin-bottom:6px}
.calc-box .desc{color:var(--sub);font-size:14px;margin-bottom:20px}
.field{margin-bottom:16px}
.field label{display:block;font-size:13.5px;font-weight:600;color:var(--text);margin-bottom:7px}
.field input,.field select{width:100%;border:1px solid #d7dee8;border-radius:10px;padding:12px 14px;font-size:15px;outline:none;background:#fff;color:var(--text);transition:.15s}
.field input:focus,.field select:focus{border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-l)}
.row{display:flex;gap:14px}
.row .field{flex:1}
.hint{font-size:13px;color:var(--sub);background:var(--primary-l);border-radius:8px;padding:9px 13px;margin-bottom:16px}
/* 按钮: 子页面用 .search 当按钮, 限定 .calc-box 作用域避免与中心页搜索框冲突 */
.calc-box button.search,.calc-box .field button{width:100%;border:0;background:var(--primary);color:#fff;padding:13px;border-radius:10px;font-size:16px;font-weight:700;cursor:pointer;transition:.15s;display:block}
.calc-box button.search:hover,.calc-box .field button:hover{background:var(--primary-d)}
/* 结果区 */
.result{margin-top:20px;border-top:1px dashed var(--line);padding-top:18px}
.rrow{display:flex;align-items:baseline;justify-content:space-between;padding:9px 0;border-bottom:1px solid #f1f5f9}
.rrow:last-child{border-bottom:0}
.rk{font-size:14px;color:var(--sub);font-weight:500}
.rv{font-size:16px;font-weight:700;color:var(--text)}
.rv.big{font-size:24px;font-weight:800;color:var(--primary-d)}
@media(max-width:560px){
  .calc-box{padding:20px 16px;border-radius:12px}
  .row{flex-direction:column;gap:0}
  .calc-box h2{font-size:19px}
}