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

body {
    font-family: 'Microsoft YaHei', sans-serif;
    background: #f5f5f5;
}

/* 导航栏 */
.navbar {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.navbar-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.8rem;
    font-weight: bold;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: white;
    text-decoration: none;
    transition: opacity 0.3s;
}

.nav-links a:hover {
    opacity: 0.8;
}

.cart-icon {
    position: relative;
    cursor: pointer;
    font-size: 1.5rem;
}

.cart-count {
    position: absolute;
    top: -8px;
    right: -8px;
    background: #ff4444;
    color: white;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.75rem;
}

/* 搜索栏 */
.search-bar {
    background: white;
    padding: 1.5rem 2rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.search-container {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    gap: 0.5rem;
}

.search-input {
    flex: 1;
    padding: 0.8rem 1rem;
    border: 2px solid #ddd;
    border-radius: 25px;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.3s;
}

.search-input:focus {
    border-color: #667eea;
}

.search-btn {
    background: #667eea;
    color: white;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 25px;
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

.search-btn:hover {
    background: #5568d3;
}

/* 主容器 */
.container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
}

/* 分类导航 */
.categories {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    justify-content: center;
}

.category-btn {
    padding: 0.6rem 1.5rem;
    border: none;
    background: white;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.95rem;
    transition: all 0.3s;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.category-btn:hover,
.category-btn.active {
    background: #667eea;
    color: white;
}

/* 产品网格 */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 2rem;
}

/* 产品卡片 */
.product-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 3px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.product-image {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
}

.product-info {
    padding: 1.2rem;
}

.product-title {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: #333;
}

.product-desc {
    font-size: 0.85rem;
    color: #888;
    margin-bottom: 0.8rem;
}

.product-price {
    font-size: 1.4rem;
    color: #ff4444;
    font-weight: bold;
    margin-bottom: 1rem;
}

.add-to-cart {
    width: 100%;
    padding: 0.8rem;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

.add-to-cart:hover {
    background: #5568d3;
}

/* 购物车侧边栏 */
.cart-sidebar {
    position: fixed;
    top: 0;
    right: -400px;
    width: 400px;
    height: 100vh;
    background: white;
    box-shadow: -5px 0 20px rgba(0,0,0,0.2);
    z-index: 1000;
    transition: right 0.3s;
    display: flex;
    flex-direction: column;
}

.cart-sidebar.open {
    right: 0;
}

.cart-header {
    padding: 1.5rem;
    background: #667eea;
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.close-cart {
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

.cart-items {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

.cart-item {
    display: flex;
    gap: 1rem;
    padding: 1rem;
    border-bottom: 1px solid #eee;
}

.cart-item-image {
    width: 80px;
    height: 80px;
    background: #f5f7fa;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
}

.cart-item-info {
    flex: 1;
}

.cart-item-title {
    font-size: 1rem;
    margin-bottom: 0.3rem;
}

.cart-item-price {
    color: #ff4444;
    font-weight: bold;
}

.cart-item-quantity {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.qty-btn {
    width: 28px;
    height: 28px;
    border: 1px solid #ddd;
    background: white;
    cursor: pointer;
    border-radius: 4px;
}

.cart-footer {
    padding: 1.5rem;
    background: #f9f9f9;
    border-top: 1px solid #eee;
}

.cart-total {
    display: flex;
    justify-content: space-between;
    font-size: 1.3rem;
    margin-bottom: 1rem;
}

.checkout-btn {
    width: 100%;
    padding: 1rem;
    background: #ff4444;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    cursor: pointer;
    transition: background 0.3s;
}

.checkout-btn:hover {
    background: #cc0000;
}

/* 遮罩层 */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 999;
    display: none;
}

.overlay.show {
    display: block;
}

/* 提示消息 */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background: #333;
    color: white;
    padding: 1rem 2rem;
    border-radius: 8px;
    z-index: 1001;
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        transform: translateX(-50%) translateY(100px);
        opacity: 0;
    }
    to {
        transform: translateX(-50%) translateY(0);
        opacity: 1;
    }
}

/* 空购物车 */
.empty-cart {
    text-align: center;
    padding: 3rem;
    color: #888;
}

.empty-cart-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
}

/* 响应式 */
@media (max-width: 768px) {
    .cart-sidebar {
        width: 100%;
        right: -100%;
    }

    .nav-links {
        display: none;
    }
}

/* 页脚 */
.footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 2rem;
    margin-top: 3rem;
}