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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --text-color: #333;
    --bg-color: #f8f9fa;
    --white: #ffffff;
    --border-color: #e0e0e0;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 1rem 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand h1 {
    color: var(--primary-color);
    font-size: 1.8rem;
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-link:hover,
.nav-link.active {
    color: var(--secondary-color);
}

.nav-icons {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.cart-icon {
    position: relative;
    color: var(--text-color);
    font-size: 1.5rem;
    text-decoration: none;
}

.cart-count {
    position: absolute;
    top: -8px;
    right: -8px;
    background: var(--accent-color);
    color: var(--white);
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
    font-weight: bold;
}

/* 首页横幅 */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: var(--white);
    padding: 100px 20px;
    text-align: center;
}

.hero-content h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.btn-primary {
    display: inline-block;
    padding: 12px 30px;
    background: var(--accent-color);
    color: var(--white);
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

/* 产品区域 */
.products-section {
    padding: 60px 20px;
}

.about-section,
.contact-section {
    padding: 60px 20px;
    background: var(--white);
    margin-top: 2rem;
    box-shadow: var(--shadow);
}

.about-content,
.contact-content {
    display: grid;
    gap: 2rem;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    align-items: center;
}

.about-text,
.contact-text {
    margin-bottom: 1rem;
    color: #555;
}

.about-highlights {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 0.8rem;
}

.about-highlights li {
    font-weight: 600;
    color: var(--primary-color);
}

.contact-details p {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
    font-weight: 600;
}

.contact-form {
    background: var(--bg-color);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.contact-submit {
    width: 100%;
    margin-top: 0.5rem;
    text-align: center;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--primary-color);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.product-card {
    background: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.15);
}

.product-image {
    width: 100%;
    height: 250px;
    object-fit: cover;
    background: #f0f0f0;
}

.product-info {
    padding: 1.5rem;
}

.product-name {
    font-size: 1.2rem;
    font-weight: bold;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.product-description {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.product-price {
    font-size: 1.5rem;
    color: var(--accent-color);
    font-weight: bold;
    margin-bottom: 1rem;
}

.product-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-add-cart,
.btn-view-details {
    flex: 1;
    padding: 10px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    transition: background 0.3s;
}

.btn-add-cart {
    background: var(--secondary-color);
    color: var(--white);
}

.btn-add-cart:hover {
    background: #2980b9;
}

.btn-view-details {
    background: var(--primary-color);
    color: var(--white);
}

.btn-view-details:hover {
    background: #1a252f;
}

/* 购物车侧边栏 */
.cart-sidebar {
    position: fixed;
    right: -400px;
    top: 0;
    width: 400px;
    height: 100vh;
    background: var(--white);
    box-shadow: -2px 0 10px rgba(0,0,0,0.1);
    transition: right 0.3s;
    z-index: 2000;
    display: flex;
    flex-direction: column;
}

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

.cart-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.cart-header h3 {
    color: var(--primary-color);
}

.close-cart {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-color);
}

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

.cart-item {
    display: flex;
    gap: 1rem;
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 1rem;
}

.cart-item-image {
    width: 80px;
    height: 80px;
    object-fit: cover;
    border-radius: 5px;
}

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

.cart-item-name {
    font-weight: bold;
    margin-bottom: 0.5rem;
}

.cart-item-price {
    color: var(--accent-color);
    font-weight: bold;
    margin-bottom: 0.5rem;
}

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

.quantity-btn {
    width: 25px;
    height: 25px;
    border: 1px solid var(--border-color);
    background: var(--white);
    cursor: pointer;
    border-radius: 3px;
}

.quantity-btn:hover {
    background: var(--bg-color);
}

.remove-item {
    background: var(--accent-color);
    color: var(--white);
    border: none;
    padding: 5px 10px;
    border-radius: 3px;
    cursor: pointer;
    font-size: 0.8rem;
}

.empty-cart {
    text-align: center;
    color: #999;
    padding: 2rem;
}

.cart-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.cart-total {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.btn-checkout {
    width: 100%;
    padding: 12px;
    background: var(--accent-color);
    color: var(--white);
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.3s;
}

.btn-checkout:hover {
    background: #c0392b;
}

/* 产品详情模态框 */
.product-modal {
    display: none;
    position: fixed;
    z-index: 3000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    overflow: auto;
}

.product-modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--white);
    margin: auto;
    padding: 2rem;
    border-radius: 10px;
    max-width: 900px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    position: relative;
}

.close-modal {
    position: absolute;
    right: 20px;
    top: 20px;
    font-size: 2rem;
    color: var(--text-color);
    cursor: pointer;
}

.close-modal:hover {
    color: var(--accent-color);
}

.modal-body {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-top: 2rem;
}

.modal-image {
    width: 100%;
    border-radius: 10px;
}

.modal-info h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.modal-price {
    font-size: 2rem;
    color: var(--accent-color);
    font-weight: bold;
    margin-bottom: 1rem;
}

.modal-description {
    color: #666;
    line-height: 1.8;
    margin-bottom: 2rem;
}

/* 支付模态框 */
.payment-modal {
    display: none;
    position: fixed;
    z-index: 4000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    overflow: auto;
}

.payment-modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.payment-content {
    background: var(--white);
    margin: auto;
    padding: 2rem;
    border-radius: 10px;
    max-width: 500px;
    width: 90%;
    position: relative;
}

.close-payment {
    position: absolute;
    right: 20px;
    top: 20px;
    font-size: 2rem;
    color: var(--text-color);
    cursor: pointer;
}

.close-payment:hover {
    color: var(--accent-color);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 1rem;
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
}

.payment-summary {
    background: var(--bg-color);
    padding: 1rem;
    border-radius: 5px;
    margin-bottom: 1.5rem;
}

.payment-summary p {
    font-size: 1.2rem;
    font-weight: bold;
    color: var(--primary-color);
}

.btn-pay {
    width: 100%;
    padding: 12px;
    background: var(--accent-color);
    color: var(--white);
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.3s;
}

.btn-pay:hover {
    background: #c0392b;
}

/* 页脚 */
.footer {
    background: var(--primary-color);
    color: var(--white);
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .hero-content h2 {
        font-size: 2rem;
    }

    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 1rem;
    }

    .cart-sidebar {
        width: 100%;
        right: -100%;
    }

    .modal-body {
        grid-template-columns: 1fr;
    }

    .modal-content {
        padding: 1rem;
    }
}