/* ============================================================
   金泰锅炉 全站样式（PC + 移动端等价）
   ============================================================ */
:root{
  --brand:#c8102e;        /* 工业红，主色 */
  --brand-dark:#9a0c22;
  --ink:#1f2933;
  --muted:#6b7785;
  --line:#e3e8ee;
  --bg:#f5f7fa;
  --card:#fff;
  --radius:10px;
  --maxw:1200px;
}
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:"Microsoft YaHei","PingFang SC",system-ui,sans-serif;color:var(--ink);background:var(--bg);line-height:1.6;font-size:15px}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{width:100%;max-width:var(--maxw);margin:0 auto;padding:0 16px}

/* ---------- Header ---------- */
.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{display:flex;align-items:center;font-weight:700;font-size:20px;color:var(--brand)}
.logo img{height:40px}
.logo-text{color:var(--brand)}
.site-nav ul{display:flex;gap:4px;list-style:none}
.site-nav a{display:block;padding:8px 14px;border-radius:6px;color:var(--ink);font-size:15px;transition:.2s}
.site-nav a:hover{color:var(--brand);background:var(--bg)}
.site-nav li.active a{color:#fff;background:var(--brand)}
.nav-toggle{display:none;background:none;border:1px solid var(--line);border-radius:6px;font-size:20px;width:42px;height:38px;cursor:pointer}

/* ---------- Layout ---------- */
.site-main{min-height:60vh}
.section{padding:48px 0}
.section-title{text-align:center;margin-bottom:28px}
.section-title h2{font-size:26px;color:var(--ink)}
.section-title p{color:var(--muted);margin-top:6px}

/* ---------- Banner ---------- */
.home-banner{position:relative;background:linear-gradient(135deg,var(--brand),var(--brand-dark));color:#fff}
.banner-slide{min-height:360px;display:flex;align-items:center;background-size:cover;background-position:center}
.banner-slide .overlay{padding:40px 0;width:100%;background:rgba(0,0,0,.35)}
.banner-slide h1{font-size:36px;margin-bottom:12px}
.banner-slide p{font-size:17px;max-width:620px;opacity:.95}
.banner-dots{position:absolute;bottom:16px;left:50%;transform:translateX(-50%);display:flex;gap:8px}
.banner-dots span{width:10px;height:10px;border-radius:50%;background:rgba(255,255,255,.5);cursor:pointer}
.banner-dots span.on{background:#fff}

/* ---------- Grid / Cards ---------- */
.grid{display:grid;gap:20px}
.grid-4{grid-template-columns:repeat(4,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-2{grid-template-columns:repeat(2,1fr)}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;transition:.2s}
.card:hover{box-shadow:0 8px 24px rgba(0,0,0,.08);transform:translateY(-2px)}
.card .thumb{aspect-ratio:4/3;background:var(--bg);overflow:hidden}
.card .thumb img{width:100%;height:100%;object-fit:cover}
.card .body{padding:14px 16px}
.card .body h3{font-size:16px;margin-bottom:6px}
.card .body p{color:var(--muted);font-size:13px}
.tag{display:inline-block;background:var(--bg);color:var(--muted);border-radius:4px;padding:2px 8px;font-size:12px;margin-right:6px}
.price-row{margin-top:8px;color:var(--brand);font-weight:600}

/* ---------- Buttons ---------- */
.btn{display:inline-block;background:var(--brand);color:#fff;padding:10px 22px;border-radius:6px;font-size:15px;cursor:pointer;border:none;transition:.2s}
.btn:hover{background:var(--brand-dark)}
.btn-mini{display:inline-block;background:var(--brand);color:#fff;padding:5px 14px;border-radius:5px;font-size:13px}
.btn-ghost{background:#fff;color:var(--brand);border:1px solid var(--brand)}

/* ---------- Page hero ---------- */
.page-hero{background:linear-gradient(135deg,var(--brand),var(--brand-dark));color:#fff;padding:40px 0;text-align:center}
.page-hero h1{font-size:28px}
.page-hero p{opacity:.92;margin-top:6px}

/* ---------- Breadcrumb ---------- */
.crumb{padding:14px 0;color:var(--muted);font-size:13px}
.crumb a:hover{color:var(--brand)}

/* ---------- Product detail ---------- */
.detail-wrap{display:grid;grid-template-columns:1fr 1fr;gap:32px;align-items:start}
.spec-table{width:100%;border-collapse:collapse;margin-top:14px}
.spec-table th,.spec-table td{border:1px solid var(--line);padding:10px 12px;text-align:left;font-size:14px}
.spec-table th{background:var(--bg);width:140px;color:var(--muted);font-weight:600}
.gallery{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:12px}
.gallery img{border:1px solid var(--line);border-radius:6px}
.rich-content img{max-width:100%}
.rich-content{padding:8px 0;color:#334}

/* ---------- Forms ---------- */
.form{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;max-width:640px}
.field{margin-bottom:16px}
.field label{display:block;margin-bottom:6px;font-weight:600;font-size:14px}
.field input,.field textarea,.field select{width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:6px;font-size:14px;font-family:inherit}
.field textarea{min-height:120px;resize:vertical}
.alert{padding:12px 16px;border-radius:6px;margin-bottom:16px}
.alert-ok{background:#e7f7ec;color:#1a7f37;border:1px solid #b7e4c7}
.alert-err{background:#fdeaea;color:#c0392b;border:1px solid #f5c6c6}

/* ---------- Pager ---------- */
.pager{display:flex;gap:6px;justify-content:center;margin:28px 0}
.pager a{padding:7px 12px;border:1px solid var(--line);border-radius:6px;background:#fff}
.pager a.active{background:var(--brand);color:#fff;border-color:var(--brand)}

/* ---------- Footer ---------- */
.site-footer{background:#1f2933;color:#cbd5e1;margin-top:40px;padding:36px 0 0}
.footer-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.footer-grid h4{color:#fff;margin-bottom:12px;font-size:16px}
.footer-grid p{margin-bottom:6px;font-size:14px}
.footer-grid a:hover{color:#fff}
.footer-bottom{border-top:1px solid #38444f;margin-top:24px;padding:14px 0;text-align:center;font-size:13px;color:#8a97a5}

/* ---------- Contact ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:32px}
.map-box{background:var(--bg);border:1px solid var(--line);border-radius:var(--radius);min-height:280px;display:flex;align-items:center;justify-content:center;color:var(--muted)}

/* ---------- Admin ---------- */
.admin-body{background:var(--bg)}
.admin-login{max-width:380px;margin:80px auto;background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:32px}
.admin-bar{background:#1f2933;color:#fff}
.admin-bar .container{display:flex;align-items:center;justify-content:space-between;height:54px}
.admin-bar a{color:#cbd5e1}
.admin-layout{display:grid;grid-template-columns:200px 1fr;min-height:calc(100vh - 54px)}
.admin-side{background:#fff;border-right:1px solid var(--line);padding:16px}
.admin-side a{display:block;padding:10px 12px;border-radius:6px;color:var(--ink);font-size:14px}
.admin-side a:hover,.admin-side a.active{background:var(--brand);color:#fff}
.admin-main{padding:24px}
.admin-main h2{margin-bottom:16px}
.table{width:100%;border-collapse:collapse;background:#fff}
.table th,.table td{border:1px solid var(--line);padding:10px;font-size:14px;text-align:left}
.table th{background:var(--bg)}
.table img{height:42px;border-radius:4px}
.admin-toolbar{display:flex;gap:10px;margin-bottom:16px;flex-wrap:wrap}
.admin-toolbar input,.admin-toolbar select{padding:8px 10px;border:1px solid var(--line);border-radius:6px}
.muted{color:var(--muted)}
.right{text-align:right}
.nowrap{white-space:nowrap}

/* ---------- Responsive ---------- */
@media (max-width:960px){
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .grid-3{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:768px){
  .nav-toggle{display:block}
  .site-nav{position:absolute;top:64px;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);display:none}
  .site-nav.open{display:block}
  .site-nav ul{flex-direction:column;padding:8px 0}
  .site-nav li.active a{border-radius:0}
  .banner-slide{min-height:260px}
  .banner-slide h1{font-size:24px}
  .grid-4,.grid-3,.grid-2{grid-template-columns:1fr}
  .detail-wrap,.contact-grid{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .admin-layout{grid-template-columns:1fr}
  .admin-side{display:none}
  .section{padding:32px 0}
}