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

:root {
    --primary-color: #1677ff;
    --primary-hover: #4096ff;
    --success-color: #52c41a;
    --error-color: #ff4d4f;
    --warning-color: #faad14;
    --text-primary: #262626;
    --text-secondary: #8c8c8c;
    --border-color: #d9d9d9;
    --bg-color: #f5f5f5;
    --white: #ffffff;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 4px 16px rgba(0, 0, 0, 0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    width: 100%;
}

/* 头部导航 */
.header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-hover) 100%);
    color: var(--white);
    padding: 16px 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 24px;
    font-weight: 600;
}

.logo-icon {
    font-size: 32px;
}

.nav {
    display: flex;
    gap: 30px;
    align-items: center;
}

.nav-link {
    color: var(--white);
    text-decoration: none;
    font-size: 16px;
    padding: 8px 16px;
    border-radius: 6px;
    transition: background 0.3s ease;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    background: rgba(255, 255, 255, 0.2);
}

.cart-count {
    background: var(--error-color);
    color: var(--white);
    border-radius: 12px;
    padding: 2px 8px;
    font-size: 12px;
    margin-left: 6px;
}

/* 主要内容区域 */
.main-content {
    flex: 1;
    padding: 30px 0;
}

.page {
    display: none;
}

.page.active {
    display: block;
}

/* 页面头部 */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
    gap: 20px;
}

.page-header h1 {
    font-size: 28px;
    color: var(--text-primary);
}

.search-bar {
    display: flex;
    gap: 10px;
}

.search-bar input {
    padding: 10px 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 14px;
    width: 300px;
}

.search-btn {
    padding: 10px 20px;
    background: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
}

/* 分类筛选 */
.category-filter {
    display: flex;
    gap: 12px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.category-btn {
    padding: 8px 20px;
    border: 1px solid var(--border-color);
    background: var(--white);
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s ease;
}

.category-btn:hover,
.category-btn.active {
    background: var(--primary-color);
    color: var(--white);
    border-color: var(--primary-color);
}

/* 商品网格 */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 24px;
}

.product-card {
    background: var(--white);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.product-image {
    width: 100%;
    height: 200px;
    background: var(--bg-color);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.product-info {
    padding: 16px;
}

.product-name {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--text-primary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.product-desc {
    font-size: 12px;
    color: var(--text-secondary);
    margin-bottom: 12px;
    height: 36px;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

.product-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.product-price {
    font-size: 20px;
    font-weight: 600;
    color: var(--error-color);
}

.btn {
    padding: 8px 16px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s ease;
    font-family: inherit;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
}

.btn-success {
    background: var(--success-color);
    color: var(--white);
}

.btn-success:hover {
    background: #73d13d;
}

.btn-secondary {
    background: var(--white);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

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

.btn-large {
    padding: 12px 32px;
    font-size: 16px;
}

/* 商品详情 */
.back-btn {
    background: none;
    border: none;
    color: var(--primary-color);
    font-size: 16px;
    cursor: pointer;
    margin-bottom: 20px;
    padding: 8px 0;
}

.product-detail {
    background: var(--white);
    border-radius: 12px;
    padding: 30px;
    box-shadow: var(--shadow);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.detail-image {
    width: 100%;
    height: 400px;
    background: var(--bg-color);
    border-radius: 12px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.detail-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.detail-info h2 {
    font-size: 24px;
    margin-bottom: 16px;
}

.detail-price {
    font-size: 32px;
    color: var(--error-color);
    font-weight: 600;
    margin-bottom: 20px;
}

.detail-desc {
    color: var(--text-secondary);
    margin-bottom: 30px;
    line-height: 1.8;
}

.detail-actions {
    display: flex;
    gap: 12px;
}

.quantity-selector {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.quantity-btn {
    width: 32px;
    height: 32px;
    border: 1px solid var(--border-color);
    background: var(--white);
    border-radius: 4px;
    cursor: pointer;
    font-size: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.quantity-input {
    width: 60px;
    text-align: center;
    padding: 6px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

/* 购物车 */
.cart-content {
    background: var(--white);
    border-radius: 12px;
    padding: 30px;
    box-shadow: var(--shadow);
}

.cart-empty,
.orders-empty {
    text-align: center;
    padding: 60px 20px;
}

.empty-icon {
    font-size: 80px;
    margin-bottom: 20px;
}

.cart-empty p,
.orders-empty p {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.cart-item {
    display: flex;
    gap: 20px;
    padding: 20px;
    border-bottom: 1px solid var(--border-color);
    align-items: center;
}

.cart-item:last-child {
    border-bottom: none;
}

.cart-item-image {
    width: 100px;
    height: 100px;
    background: var(--bg-color);
    border-radius: 8px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.cart-item-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

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

.cart-item-name {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 8px;
}

.cart-item-price {
    color: var(--error-color);
    font-size: 18px;
    font-weight: 600;
}

.cart-item-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.remove-btn {
    background: none;
    border: none;
    color: var(--error-color);
    cursor: pointer;
    font-size: 14px;
    padding: 4px 8px;
}

.cart-summary {
    margin-top: 30px;
    padding-top: 30px;
    border-top: 2px solid var(--border-color);
}

.summary-row {
    display: flex;
    justify-content: space-between;
    margin-bottom: 16px;
    font-size: 16px;
}

.total-price {
    font-size: 24px;
    font-weight: 600;
    color: var(--error-color);
}

/* 订单确认 */
.checkout-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 30px;
}

.checkout-section {
    background: var(--white);
    border-radius: 12px;
    padding: 24px;
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.checkout-section h2 {
    font-size: 20px;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border-color);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
}

.form-group textarea {
    resize: vertical;
}

.checkout-item {
    display: flex;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-color);
}

.checkout-summary {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 2px solid var(--border-color);
}

.summary-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 12px;
    font-size: 14px;
}

.summary-item.total {
    font-size: 20px;
    font-weight: 600;
    color: var(--error-color);
    padding-top: 12px;
    border-top: 1px solid var(--border-color);
}

.payment-methods {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.payment-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.payment-option:hover,
.payment-option.active {
    border-color: var(--primary-color);
    background: rgba(22, 119, 255, 0.05);
}

.payment-option input[type="radio"] {
    width: 20px;
    height: 20px;
}

.payment-icon {
    font-size: 24px;
}

.payment-name {
    font-size: 16px;
    font-weight: 500;
}

.checkout-actions {
    display: flex;
    gap: 16px;
    justify-content: flex-end;
    margin-top: 30px;
}

/* 支付页面 */
.payment-content {
    max-width: 600px;
    margin: 0 auto;
    background: var(--white);
    border-radius: 12px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
}

.payment-info h1 {
    text-align: center;
    margin-bottom: 30px;
}

.order-info-box {
    background: var(--bg-color);
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 30px;
}

.order-info-box p {
    margin-bottom: 12px;
    font-size: 16px;
}

.order-info-box p:last-child {
    margin-bottom: 0;
}

.price {
    color: var(--error-color);
    font-size: 20px;
    font-weight: 600;
}

.qr-code-container {
    text-align: center;
    margin: 30px 0;
}

.qr-code-placeholder {
    display: inline-block;
    padding: 30px;
    background: var(--bg-color);
    border-radius: 12px;
}

.qr-code-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.qr-code-mock {
    width: 200px;
    height: 200px;
    background: var(--white);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    margin: 20px auto;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 4px;
    padding: 8px;
}

.qr-pattern {
    background: var(--text-primary);
    border-radius: 2px;
}

.qr-pattern:nth-child(even) {
    background: transparent;
}

.qr-tip {
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: 12px;
}

.payment-status {
    text-align: center;
    margin: 30px 0;
    min-height: 100px;
}

.status-pending {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.status-success {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.success-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: var(--success-color);
    color: var(--white);
    font-size: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.success-tip {
    color: var(--text-secondary);
    font-size: 14px;
}

.payment-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-top: 30px;
}

/* 订单列表 */
.order-card {
    background: var(--white);
    border-radius: 12px;
    padding: 24px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
}

.order-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 16px;
}

.order-number {
    font-weight: 600;
}

.order-status {
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

.order-status.pending {
    background: #fff7e6;
    color: var(--warning-color);
}

.order-status.paid {
    background: #f6ffed;
    color: var(--success-color);
}

.order-items {
    margin-bottom: 16px;
}

.order-item {
    display: flex;
    gap: 16px;
    margin-bottom: 12px;
}

.order-item:last-child {
    margin-bottom: 0;
}

.order-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 16px;
    border-top: 1px solid var(--border-color);
}

/* 底部 */
.footer {
    background: var(--white);
    padding: 20px 0;
    text-align: center;
    color: var(--text-secondary);
    border-top: 1px solid var(--border-color);
    margin-top: auto;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 16px;
    }

    .nav {
        width: 100%;
        justify-content: center;
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .search-bar input {
        width: 100%;
    }

    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
        gap: 16px;
    }

    .product-detail {
        grid-template-columns: 1fr;
    }

    .checkout-content {
        grid-template-columns: 1fr;
    }

    .cart-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .cart-item-actions {
        width: 100%;
        justify-content: space-between;
    }

    .checkout-actions,
    .payment-actions {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}