@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --color-brand: #2563EB;
    --color-brand-dark: #1D4ED8;
    --color-text: #1F2937;
    --color-muted: #6B7280;
    --color-border: #E5E7EB;
    --color-bg: #F9FAFB;
    --color-danger: #DC2626;
    --color-success: #16A34A;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Inter', ui-sans-serif, system-ui, sans-serif;
    color: var(--color-text);
    background: #fff;
    line-height: 1.5;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* ---------- Alerts ---------- */
.alert {
    padding: 12px 20px;
    text-align: center;
    font-weight: 500;
}
.alert-success { background: #DCFCE7; color: var(--color-success); }
.alert-error { background: #FEE2E2; color: var(--color-danger); }

/* ---------- Buttons ---------- */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    font-weight: 600;
    font-size: 14px;
    text-align: center;
}
.btn-primary { background: var(--color-brand); color: #fff; }
.btn-primary:hover { background: var(--color-brand-dark); }
.btn-secondary { background: #fff; color: var(--color-text); border: 1px solid var(--color-border); }
.btn-secondary:hover { background: var(--color-bg); }
.btn-danger { background: var(--color-danger); color: #fff; }
.btn-sm { padding: 6px 12px; font-size: 13px; }
.btn-block { width: 100%; }
.btn-link { background: none; border: none; color: var(--color-brand); cursor: pointer; font-size: 14px; padding: 0; }
.text-danger { color: var(--color-danger); }
.text-success { color: var(--color-success); }
.inline-form { display: inline-block; margin: 0; }

/* ---------- Header ---------- */
.site-header {
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    background: #fff;
    z-index: 100;
}
.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 20px;
    gap: 20px;
    flex-wrap: wrap;
}
.logo { font-size: 22px; font-weight: 700; color: var(--color-brand); }
.main-menu ul { list-style: none; display: flex; gap: 20px; margin: 0; padding: 0; }
.main-menu a { font-weight: 500; }
.main-menu a:hover { color: var(--color-brand); }
.header-actions { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.search-form { display: flex; }
.search-form input {
    padding: 8px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius) 0 0 var(--radius);
    outline: none;
}
.search-form button {
    border: 1px solid var(--color-border);
    border-left: none;
    background: var(--color-bg);
    border-radius: 0 var(--radius) var(--radius) 0;
    cursor: pointer;
    padding: 0 12px;
}
.cart-icon { position: relative; font-size: 20px; }
.cart-count {
    position: absolute;
    top: -8px;
    right: -10px;
    background: var(--color-danger);
    color: #fff;
    font-size: 11px;
    border-radius: 50%;
    width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.user-greeting { font-size: 14px; color: var(--color-muted); }
.menu-toggle { display: none; background: none; border: none; font-size: 22px; cursor: pointer; }

/* ---------- Hero / Sections ---------- */
.hero {
    background: linear-gradient(135deg, var(--color-brand), var(--color-brand-dark));
    color: #fff;
    text-align: center;
    padding: 80px 20px;
}
.hero h1 { font-size: 42px; margin-bottom: 10px; }
.hero .btn-primary { background: #fff; color: var(--color-brand); margin-top: 20px; }
.section-title { font-size: 26px; margin: 40px 0 20px; font-weight: 700; }

.category-list { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 20px; }
.category-item {
    padding: 8px 18px;
    border: 1px solid var(--color-border);
    border-radius: 999px;
    font-weight: 500;
}
.category-item:hover { background: var(--color-brand); color: #fff; border-color: var(--color-brand); }

/* ---------- Product Grid / Card ---------- */
.product-grid, .news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}
.product-card, .news-card {
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    overflow: hidden;
    background: #fff;
    box-shadow: var(--shadow);
    transition: transform .15s ease;
}
.product-card:hover, .news-card:hover { transform: translateY(-3px); }
.product-card img, .news-card img { height: 200px; width: 100%; object-fit: cover; }
.product-card-body, .news-card-body { padding: 14px; }
.product-card-body h3 { font-size: 15px; margin: 0 0 8px; }
.price { margin-bottom: 10px; }
.old-price { text-decoration: line-through; color: var(--color-muted); margin-right: 8px; font-size: 13px; }
.new-price { color: var(--color-brand); font-weight: 700; font-size: 16px; }
.news-category { color: var(--color-brand); font-size: 12px; font-weight: 600; text-transform: uppercase; }

.empty-state { text-align: center; color: var(--color-muted); padding: 40px 0; }

/* ---------- Filters / Pagination ---------- */
.filter-form { display: flex; gap: 10px; margin-bottom: 24px; flex-wrap: wrap; align-items: center; }
.filter-form input, .filter-form select {
    padding: 8px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
}
.filter-form a {
    padding: 6px 14px;
    border: 1px solid var(--color-border);
    border-radius: 999px;
    font-size: 14px;
}
.filter-form a.active { background: var(--color-brand); color: #fff; border-color: var(--color-brand); }

.pagination { display: flex; gap: 8px; margin-bottom: 40px; }
.pagination a {
    padding: 8px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
}
.pagination a.active { background: var(--color-brand); color: #fff; }

/* ---------- Product Detail ---------- */
.product-detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; margin: 30px 0; }
.main-image { width: 100%; border-radius: var(--radius); }
.thumbnail-list { display: flex; gap: 8px; margin-top: 10px; }
.thumb { width: 60px; height: 60px; object-fit: cover; border-radius: 6px; cursor: pointer; border: 1px solid var(--color-border); }
.stock-info { color: var(--color-muted); font-size: 14px; }
.add-to-cart-form { display: flex; align-items: center; gap: 10px; margin-top: 20px; }
.add-to-cart-form input[type=number] { width: 70px; padding: 8px; border: 1px solid var(--color-border); border-radius: var(--radius); }

/* ---------- Article ---------- */
.article-detail { max-width: 800px; margin: 30px auto; }
.article-detail h1 { font-size: 30px; margin: 10px 0; }
.article-date { color: var(--color-muted); font-size: 14px; margin-bottom: 20px; }
.article-image { width: 100%; border-radius: var(--radius); margin-bottom: 20px; }
.article-content { line-height: 1.8; }

/* ---------- Cart ---------- */
.cart-table, .order-table, .admin-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}
.cart-table th, .cart-table td,
.order-table th, .order-table td,
.admin-table th, .admin-table td {
    padding: 12px;
    border-bottom: 1px solid var(--color-border);
    text-align: left;
    font-size: 14px;
}
.cart-product-cell { display: flex; align-items: center; gap: 10px; }
.cart-product-cell img { width: 50px; height: 50px; object-fit: cover; border-radius: 6px; }
.qty-input { width: 60px; padding: 6px; border: 1px solid var(--color-border); border-radius: 6px; }
.cart-summary { text-align: right; }
.cart-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 10px; }

/* ---------- Checkout / Contact / Auth Forms ---------- */
.checkout-grid, .contact-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 30px; margin: 30px 0; }
.checkout-form label, .contact-form label, .admin-form label, .auth-box label {
    display: block;
    margin: 14px 0 6px;
    font-weight: 500;
    font-size: 14px;
}
.checkout-form input, .checkout-form textarea,
.contact-form input, .contact-form textarea,
.admin-form input, .admin-form textarea, .admin-form select,
.auth-box input, .auth-box select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 14px;
}
.checkout-summary, .contact-info {
    background: var(--color-bg);
    border-radius: var(--radius);
    padding: 20px;
    height: fit-content;
}
.checkout-summary ul { list-style: none; padding: 0; }
.checkout-summary li { display: flex; justify-content: space-between; padding: 6px 0; font-size: 14px; }
.checkout-total { font-size: 18px; text-align: right; margin-top: 10px; }
.checkbox-label { display: flex; align-items: center; gap: 8px; font-weight: 400 !important; }
.checkbox-label input { width: auto; }

/* ---------- Auth ---------- */
.auth-page { display: flex; justify-content: center; padding: 60px 0; }
.auth-box { width: 100%; max-width: 400px; border: 1px solid var(--color-border); border-radius: var(--radius); padding: 30px; box-shadow: var(--shadow); }
.auth-switch { text-align: center; margin-top: 16px; font-size: 14px; }
.auth-switch a { color: var(--color-brand); font-weight: 600; }

/* ---------- Order status badges ---------- */
.badge {
    padding: 4px 10px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 600;
    white-space: nowrap;
}
.badge-status-ChoXacNhan { background: #FEF3C7; color: #92400E; }
.badge-status-DangXuLy { background: #DBEAFE; color: #1E40AF; }
.badge-status-DangGiao { background: #E0E7FF; color: #3730A3; }
.badge-status-HoanThanh { background: #DCFCE7; color: #166534; }
.badge-status-DaHuy { background: #FEE2E2; color: #991B1B; }
.badge-status-ChuaXuLy { background: #FEE2E2; color: #991B1B; }
.badge-status-DaXuLy { background: #DCFCE7; color: #166534; }

/* ---------- Footer ---------- */
.site-footer { background: #111827; color: #D1D5DB; margin-top: 60px; }
.footer-inner { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; padding: 40px 20px; }
.footer-col h4 { color: #fff; margin-bottom: 12px; }
.footer-col ul { list-style: none; padding: 0; }
.footer-col li { margin-bottom: 8px; }
.footer-bottom { text-align: center; padding: 16px; border-top: 1px solid #1F2937; font-size: 13px; }

/* ---------- Admin Layout ---------- */
.admin-layout { display: flex; min-height: 100vh; }
.admin-sidebar { width: 240px; background: #111827; color: #fff; flex-shrink: 0; }
.admin-logo { padding: 20px; font-weight: 700; font-size: 18px; border-bottom: 1px solid #1F2937; }
.admin-sidebar ul { list-style: none; padding: 0; margin: 0; }
.admin-sidebar li a { display: block; padding: 14px 20px; color: #D1D5DB; }
.admin-sidebar li.active a, .admin-sidebar li a:hover { background: var(--color-brand); color: #fff; }
.admin-content { flex: 1; padding: 30px; background: var(--color-bg); }
.admin-page-header { display: flex; justify-content: space-between; align-items: center; margin-top: 20px; }
.admin-panel { background: #fff; border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); }
.admin-grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 20px; }
.admin-table { background: #fff; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.admin-actions { display: flex; gap: 12px; }
.admin-actions a { color: var(--color-brand); font-size: 14px; }
.thumb-sm { width: 44px; height: 44px; object-fit: cover; border-radius: 6px; }
.thumb-preview { width: 120px; height: 120px; object-fit: cover; border-radius: 6px; margin: 10px 0; }
.status-update-form { display: flex; align-items: center; gap: 10px; margin: 16px 0; }

/* ---------- Stat cards ---------- */
.stat-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 16px; margin-top: 20px; }
.stat-card { background: #fff; border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); text-align: center; }
.stat-card h3 { font-size: 24px; margin: 0 0 6px; color: var(--color-brand); }
.stat-card p { margin: 0; color: var(--color-muted); font-size: 13px; }
.stat-card.highlight h3 { color: var(--color-danger); }

/* ---------- Modal ---------- */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}
.modal-box {
    background: #fff;
    border-radius: var(--radius);
    padding: 24px;
    width: 100%;
    max-width: 380px;
}
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 20px; }

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
    .main-menu { display: none; width: 100%; }
    .main-menu.open { display: block; }
    .main-menu ul { flex-direction: column; }
    .menu-toggle { display: block; }
    .product-detail-grid, .checkout-grid, .contact-grid, .admin-grid-2 { grid-template-columns: 1fr; }
    .admin-layout { flex-direction: column; }
    .admin-sidebar { width: 100%; }
    .footer-inner { grid-template-columns: 1fr; }
}