/* ============================
   全局样式 & CSS变量
   ============================ */
:root {
    --bg: #ffffff;
    --text: #222;
    --card-bg: #ffffff;
    --card-shadow: 0 4px 20px rgba(0,0,0,0.08);
    --primary: #2e7d32;
    --primary-light: #4caf50;
    --accent: #ffb300;
    --radius: 16px;
    --transition: 0.3s ease;
    --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
}
[data-theme="dark"] {
    --bg: #121212;
    --text: #eee;
    --card-bg: #1e1e1e;
    --card-shadow: 0 4px 20px rgba(0,0,0,0.5);
    --primary: #66bb6a;
    --primary-light: #81c784;
}
* { margin:0; padding:0; box-sizing:border-box; }
body { font-family: var(--font); background: var(--bg); color: var(--text); line-height:1.6; transition: background var(--transition), color var(--transition); }
a { color: var(--primary); text-decoration:none; }
a:hover { color: var(--primary-light); }
img { max-width:100%; }
.container { max-width:1200px; margin:0 auto; padding:0 20px; }
.btn { display:inline-block; padding:10px 24px; border-radius:30px; border:none; cursor:pointer; font-weight:600; transition: var(--transition); }
.btn-primary { background: var(--primary); color:#fff; }
.btn-primary:hover { background: var(--primary-light); transform:translateY(-2px); box-shadow:0 8px 20px rgba(46,125,50,0.3); }
.btn-outline { background:transparent; border:2px solid var(--primary); color:var(--primary); }
.btn-outline:hover { background:var(--primary); color:#fff; }
.btn-sm { padding:6px 16px; font-size:0.9rem; }
.btn-icon { background:transparent; border:none; font-size:1.3rem; cursor:pointer; color:var(--text); padding:6px; border-radius:50%; transition:var(--transition); }
.btn-icon:hover { background:rgba(0,0,0,0.05); }
.card { background: var(--card-bg); border-radius: var(--radius); box-shadow: var(--card-shadow); overflow:hidden; transition: var(--transition); }
.card:hover { transform:translateY(-4px); box-shadow:0 12px 30px rgba(0,0,0,0.12); }
.card-img { width:100%; }
.card-body { padding:20px; }
.card-meta { display:flex; justify-content:space-between; align-items:center; margin:12px 0; }
.tag { display:inline-block; background:var(--primary); color:#fff; padding:2px 12px; border-radius:20px; font-size:0.8rem; margin-bottom:8px; }
.price { font-size:1.3rem; font-weight:700; color:var(--accent); }
.rating { color:var(--text); }
.form-group { margin-bottom:15px; }
.form-group input, .form-group textarea, .form-group select { width:100%; padding:12px 16px; border-radius:10px; border:1px solid #ccc; font-size:1rem; background:var(--bg); color:var(--text); }
.form-group input:focus, .form-group textarea:focus { outline:2px solid var(--primary); }
.alert { background:#e8f5e9; padding:12px 20px; border-radius:10px; margin-bottom:20px; color:#2e7d32; }

/* Header */
.header { background: var(--card-bg); box-shadow:0 2px 10px rgba(0,0,0,0.05); position:sticky; top:0; z-index:100; }
.header-inner { display:flex; align-items:center; justify-content:space-between; padding:14px 0; }
.logo { font-size:1.5rem; font-weight:700; color:var(--primary); }
.nav { display:flex; gap:20px; align-items:center; }
.nav a { font-weight:500; padding:6px 0; border-bottom:2px solid transparent; }
.nav a:hover { border-color:var(--primary); }
.header-actions { display:flex; gap:10px; align-items:center; }
.theme-switcher select { padding:6px 12px; border-radius:20px; border:1px solid #ccc; background:var(--bg); color:var(--text); }
.hamburger { display:none; }

/* Hero */
.hero h1 { font-size:2.5rem; margin-bottom:10px; }

/* Search Filter */
.search-filter { display:flex; gap:12px; flex-wrap:wrap; }
.search-filter input, .search-filter select { flex:1; min-width:180px; padding:12px 16px; border-radius:30px; border:1px solid #ddd; background:var(--card-bg); color:var(--text); }

/* Product Grid */
.product-grid { display:grid; grid-template-columns:repeat(auto-fill, minmax(280px,1fr)); gap:24px; }
.product-card .card-actions { display:flex; gap:10px; margin-top:12px; }

/* Stats */
.stats-grid { display:grid; grid-template-columns:repeat(auto-fit, minmax(180px,1fr)); gap:20px; }
.stat-card { background:var(--card-bg); border-radius:var(--radius); box-shadow:var(--card-shadow); padding:24px; display:flex; align-items:center; gap:16px; }
.stat-card i { font-size:2.5rem; color:var(--primary); }
.stat-card h3 { font-size:1.8rem; }

/* Heatmap */
.heatmap { display:flex; flex-wrap:wrap; gap:8px; justify-content:center; }
.heat-item { width:80px; height:80px; border-radius:12px; display:flex; align-items:center; justify-content:center; color:#fff; font-weight:600; font-size:0.8rem; text-align:center; transition:var(--transition); }
.heat-item:hover { transform:scale(1.08); }

/* Footer */
.footer { background: var(--card-bg); padding:30px 0; text-align:center; margin-top:40px; border-top:1px solid #e0e0e0; }
.footer-links { display:flex; gap:20px; justify-content:center; flex-wrap:wrap; margin-bottom:15px; }

/* Admin */
.admin-grid { display:grid; grid-template-columns:1fr 1fr; gap:24px; margin:30px 0; }
.table-wrap { overflow-x:auto; }
table { width:100%; border-collapse:collapse; }
th, td { padding:12px 16px; text-align:left; border-bottom:1px solid #ddd; }
th { background:var(--primary); color:#fff; }

/* Responsive */
@media (max-width:768px) {
    .nav { display:none; flex-direction:column; position:absolute; top:60px; left:0; right:0; background:var(--card-bg); padding:20px; box-shadow:0 10px 30px rgba(0,0,0,0.1); }
    .nav.open { display:flex; }
    .hamburger { display:block; }
    .admin-grid { grid-template-columns:1fr; }
    .hero h1 { font-size:1.8rem; }
    .search-filter input, .search-filter select { min-width:100%; }
}