:root {
    --primary: #5b6ef5;
    --primary-dark: #4755c5;
    --primary-light: #eef0fe;
    --text: #1a1a2e;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg: #ffffff;
    --bg-soft: #f8f9fc;
    --border: #e5e7eb;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 2px 12px rgba(0,0,0,.06);
    --shadow-hover: 0 8px 30px rgba(0,0,0,.12);
    --max-width: 1200px;
    --header-h: 64px;
    --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    padding-bottom: 60px;
}

a { color: var(--primary); text-decoration: none; transition: color .2s; }
a:hover { color: var(--primary-dark); }

img { max-width: 100%; display: block; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header {
    position: sticky; top: 0; z-index: 100;
    background: rgba(255,255,255,.95); backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    height: var(--header-h);
    display: flex; align-items: center;
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; width: 100%; }
.site-logo { font-size: 20px; font-weight: 700; color: var(--text); display: flex; align-items: center; gap: 8px; }
.site-logo span { color: var(--primary); }
.site-nav { display: flex; align-items: center; gap: 24px; }
.site-nav a { color: var(--text-secondary); font-size: 15px; font-weight: 500; }
.site-nav a:hover, .site-nav a.active { color: var(--primary); }
.search-box { display: flex; align-items: center; gap: 6px; }
.search-box input {
    padding: 8px 14px; border: 1px solid var(--border); border-radius: 20px;
    font-size: 14px; width: 180px; transition: all .2s; outline: none;
}
.search-box input:focus { border-color: var(--primary); width: 240px; }
.search-box button {
    padding: 8px 16px; background: var(--primary); color: #fff;
    border: none; border-radius: 20px; font-size: 14px; cursor: pointer;
}
.btn-contact {
    padding: 8px 18px; background: var(--primary); color: #fff;
    border: none; border-radius: 20px; font-size: 14px; cursor: pointer;
    transition: background .2s;
}
.btn-contact:hover { background: var(--primary-dark); }
.mobile-menu-btn { display: none; background: none; border: none; font-size: 22px; cursor: pointer; }

/* Hero */
.hero { text-align: center; padding: 30px 20px 30px; }
.hero h1 { font-size: 36px; font-weight: 700; margin-bottom: 12px; }
.hero p { font-size: 16px; color: var(--text-secondary); max-width: 500px; margin: 0 auto; }

/* Filters */
.filters { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; justify-content: center; padding: 0 20px 24px; }
.filter-group { display: flex; gap: 6px; flex-wrap: wrap; justify-content: center; }
.filter-chip {
    padding: 6px 16px; border-radius: 20px; font-size: 14px;
    background: var(--bg-soft); color: var(--text-secondary);
    cursor: pointer; transition: all .2s; border: 1px solid transparent;
}
.filter-chip:hover { border-color: var(--primary); }
.filter-chip.active { background: var(--primary); color: #fff; }
.sort-select {
    padding: 6px 12px; border: 1px solid var(--border); border-radius: 20px;
    font-size: 14px; background: #fff; cursor: pointer; outline: none;
}

/* Cards Grid */
.cards-grid {
    display: grid; gap: 24px; padding: 0 20px 40px;
    grid-template-columns: repeat(4, 1fr);
}
@media (max-width: 1279px) { .cards-grid { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 1023px) { .cards-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 767px)  { .cards-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; } }

.card {
    background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
    overflow: hidden; transition: all .3s; display: flex; flex-direction: column;
}
.card:hover { box-shadow: var(--shadow-hover); transform: translateY(-4px); }

.card-image {
    position: relative; aspect-ratio: 16/10; overflow: hidden; background: var(--bg-soft);
}
.card-image img { width: 100%; height: 100%; object-fit: cover; transition: transform .3s; }
.card:hover .card-image img { transform: scale(1.05); }
.card-badge {
    position: absolute; top: 10px; left: 10px; padding: 3px 10px;
    border-radius: 12px; font-size: 12px; color: #fff; font-weight: 600;
}
.badge-hot { background: #f44336; }
.badge-new { background: #4caf50; }

.card-body { padding: 16px; flex: 1; display: flex; flex-direction: column; }
.card-title { font-size: 16px; font-weight: 600; margin-bottom: 6px; }
.card-desc {
    font-size: 14px; color: var(--text-secondary); margin-bottom: 10px;
    display: -webkit-box; -webkit-line-clamp: 5; -webkit-box-orient: vertical; overflow: hidden;
}
.card-desc.expanded { -webkit-line-clamp: unset; }
.card-expand { font-size: 13px; color: var(--primary); cursor: pointer; margin-bottom: 8px; }
.card-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 10px; }
.tag-chip { font-size: 12px; padding: 2px 8px; background: var(--primary-light); color: var(--primary); border-radius: 4px; }

.card-price { display: flex; align-items: baseline; gap: 6px; margin-bottom: 12px; }
.price-now { font-size: 20px; font-weight: 700; color: var(--primary); }
.price-origin { font-size: 14px; color: var(--text-light); text-decoration: line-through; }
.price-free { font-size: 18px; font-weight: 600; color: #4caf50; }

.card-actions { display: flex; gap: 8px; margin-top: auto; }
.btn {
    flex: 1; padding: 8px 0; text-align: center; border: none; border-radius: var(--radius-sm);
    font-size: 14px; cursor: pointer; transition: all .2s; font-weight: 500;
}
.btn-demo { background: var(--primary); color: #fff; }
.btn-demo:hover { background: var(--primary-dark); }
.btn-buy { background: var(--bg-soft); color: var(--text); }
.btn-buy:hover { background: var(--border); }
.btn-contact-sm { background: var(--bg-soft); color: var(--text); }
.btn-contact-sm:hover { background: var(--border); }

/* Load more */
.load-more { text-align: center; padding: 0 20px 60px; }
.load-more button {
    padding: 12px 40px; background: var(--bg-soft); color: var(--text-secondary);
    border: 1px solid var(--border); border-radius: 24px; font-size: 15px;
    cursor: pointer; transition: all .2s;
}
.load-more button:hover { border-color: var(--primary); color: var(--primary); }

/* Footer */
.site-footer { border-top: 1px solid var(--border); padding: 24px 20px; text-align: center; }
.site-footer p { font-size: 14px; color: var(--text-light); }
.footer-links { margin-bottom: 8px; }
.footer-links a { font-size: 14px; color: var(--text-secondary); margin: 0 8px; }

/* Contact Modal */
.modal-overlay {
    position: fixed; inset: 0; background: rgba(0,0,0,.5);
    display: none; align-items: center; justify-content: center; z-index: 200;
}
.modal-overlay.show { display: flex; }
.modal {
    background: #fff; border-radius: var(--radius); padding: 32px;
    max-width: 400px; width: 90%; text-align: center;
    animation: modalIn .3s ease;
}
@keyframes modalIn { from { opacity: 0; transform: scale(.9); } to { opacity: 1; transform: scale(1); } }
.modal h3 { font-size: 20px; margin-bottom: 20px; }
.modal-item { display: flex; align-items: center; gap: 12px; padding: 10px 0; border-bottom: 1px solid var(--border); }
.modal-item:last-child { border: none; }
.modal-item .label { color: var(--text-light); width: 60px; text-align: left; }
.modal-item .value { font-weight: 500; }

/* Skeleton */
.skeleton-card {
    background: var(--bg-soft); border-radius: var(--radius); overflow: hidden;
}
.skeleton-img { aspect-ratio: 16/10; background: #eee; animation: shimmer 1.5s infinite; }
.skeleton-line { height: 14px; background: #eee; border-radius: 4px; margin: 8px 12px; animation: shimmer 1.5s infinite; }
@keyframes shimmer { 0% { background: #eee; } 50% { background: #f5f5f5; } 100% { background: #eee; } }

/* Detail page */
.detail-page { padding: 24px 20px 60px; }
.breadcrumb { display: flex; gap: 8px; font-size: 14px; color: var(--text-light); margin-bottom: 24px; }
.detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 32px; }
@media (max-width: 767px) { .detail-grid { grid-template-columns: 1fr; } }
.detail-images img { border-radius: var(--radius); width: 100%; }
.detail-info h1 { font-size: 28px; margin-bottom: 8px; }
.detail-price { display: flex; align-items: baseline; gap: 8px; margin: 12px 0; }
.detail-meta { display: flex; flex-wrap: wrap; gap: 16px; margin-bottom: 16px; color: var(--text-secondary); font-size: 14px; }
.detail-actions { display: flex; gap: 12px; margin: 20px 0; }
.detail-actions .btn { flex: none; padding: 10px 28px; }
.detail-content { margin-top: 40px; line-height: 1.8; }
.detail-content h2 { font-size: 22px; margin: 20px 0 12px; }
.related-section { margin-top: 40px; }
.related-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 767px) { .related-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; } }
.related-item { border: 1px solid var(--border); border-radius: var(--radius-sm); overflow: hidden; }
.related-item img { aspect-ratio: 16/10; object-fit: cover; }
.related-item .info { padding: 10px; }
.related-item .info h4 { font-size: 14px; }
.related-item .info .price { color: var(--primary); font-weight: 600; font-size: 14px; }

/* 404 */
.error-page { text-align: center; padding: 80px 20px; }
.error-page h1 { font-size: 72px; color: var(--primary); }
.error-page p { font-size: 18px; color: var(--text-secondary); margin: 16px 0 24px; }

/* Responsive */
@media (max-width: 767px) {
    .site-nav { display: none; }
    .mobile-menu-btn { display: block; }
    .hero h1 { font-size: 26px; }
    .hero { padding: 18px 14px 22px; }
    .search-box input { width: 120px; }
    .search-box input:focus { width: 160px; }
    .card-body { padding: 10px; }
    .card-title { font-size: 13px; margin-bottom: 4px; }
    .card-desc { font-size: 12px; -webkit-line-clamp: 4; }
    .card-tags { gap: 4px; }
    .tag-chip { font-size: 10px; padding: 1px 6px; }
    .price-now { font-size: 16px; }
    .price-origin { font-size: 12px; }
    .price-free { font-size: 14px; }
    .card-actions { gap: 6px; }
    .card-actions .btn { font-size: 12px; padding: 6px 0; }
    .card-badge { font-size: 10px; padding: 2px 6px; top: 6px; left: 6px; }
}

/* APP风格底部Tab Bar */
.tab-bar {
    position: fixed;
    bottom: 0; left: 0; right: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    background: #fff;
    box-shadow: 0 -2px 12px rgba(0,0,0,.08);
    z-index: 999;
    padding: 6px 0;
    padding-bottom: calc(6px + env(safe-area-inset-bottom, 0));
}
.tab-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
    padding: 4px 16px;
    cursor: pointer;
    transition: all .2s;
    color: #9ca3af;
}
.tab-icon {
    width: 24px; height: 24px;
    object-fit: contain;
    transition: transform .2s;
}
.tab-label {
    font-size: 11px;
    font-weight: 500;
}
.tab-item.active {
    color: #4f46e5;
}
.tab-item.active .tab-icon {
    transform: translateY(-2px) scale(1.15);
}
.tab-item.active .tab-label {
    font-weight: 600;
}

/* 前端搜索 */
.site-header { padding-bottom: 8px; }
.site-nav a { white-space: nowrap; }
@media (max-width: 767px) {
    .tab-icon { width: 22px; height: 22px; }
    .tab-label { font-size: 10px; }
    .tab-item { padding: 4px 10px; }
}

/* 详情页底部悬浮操作栏 */
.detail-action-bar {
    position: fixed;
    bottom: 0; left: 0; right: 0;
    display: flex;
    gap: 12px;
    justify-content: center;
    align-items: center;
    padding: 10px 16px;
    padding-bottom: calc(10px + env(safe-area-inset-bottom, 0));
    background: #fff;
    box-shadow: 0 -2px 12px rgba(0,0,0,.1);
    z-index: 998;
}
.detail-action-bar .btn {
    flex: 1;
    max-width: 200px;
    padding: 12px 0;
    text-align: center;
}
/* 详情页有底部栏时 body 加大底部留白 */
body:has(.detail-action-bar) { padding-bottom: 80px; }
@media (max-width: 767px) {
    .detail-action-bar { gap: 8px; padding: 8px 12px; }
    .detail-action-bar .btn { font-size: 14px; padding: 10px 0; }
}

/* 缩略图hover提示 */
.card-image {
    position: relative;
}
.card-image::after {
    content: '点击查看详情';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,.5);
    color: #fff;
    font-size: 14px;
    font-weight: 500;
    opacity: 0;
    transition: opacity .2s;
    border-radius: var(--radius) var(--radius) 0 0;
}
.card-image:hover::after {
    opacity: 1;
}