/* ================================
   CSS 变量定义 (CSS Variables)
   ================================ */
:root {
    /* 主题颜色 */
    --primary-color: #409EFF;
    --primary-hover: #0056b3;
    --success-color: #28a745;
    --danger-color: #F65266;
    
    /* 浅色主题 */
    --light-bg: #ffffff;
    --light-bg-alt: #f8f9fa;
    --light-text: #212529;
    --light-text-muted: #6c757d;
    --light-border: #e9ecef;
    --light-border-alt: #dee2e6;
    
    /* 暗色主题 */
    --dark-bg: #212529;
    --dark-bg-alt: #343a40;
    --dark-bg-hover: #495057;
    --dark-text: #e9ecef;
    --dark-text-alt: #adb5bd;
    --dark-border: #495057;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 0.75rem;
    --spacing-lg: 1rem;
    --spacing-xl: 1.25rem;
    
    /* 字体大小 */
    --font-xs: 0.65rem;
    --font-sm: 0.75rem;
    --font-base: 1rem;
    --font-lg: 1.1rem;
    --font-xl: 1.3rem;
    
    /* 圆角 */
    --border-radius: 0.375rem;
    --border-radius-lg: 0.5rem;
    
    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(64, 158, 255, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 123, 255, 0.3);
    --shadow-lg: 0 6px 16px rgba(0, 123, 255, 0.4);
}

[data-bs-theme="dark"] {
    --shadow-sm: 0 2px 8px rgba(64, 158, 255, 0.4);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 6px 16px rgba(0, 0, 0, 0.6);
}

/* ================================
   全局样式 (Global Styles)
   ================================ */
body {
    padding-top: 60px !important;
    display: flex !important;
    flex-direction: column !important;
    min-height: 100vh !important;
}

@media (min-width: 992px) {
    body {
        padding-top: 80px !important;
    }
}

.content-wrapper {
    flex: 1 !important;
    min-height: auto !important;
}

/* ================================
   警告框样式 (Alert Styles)
   ================================ */
.alert.alert-dismissible,
.alert.alert-dismissible.rounded-0,
body .alert.alert-dismissible,
.alert-primary, .alert-secondary, .alert-success, 
.alert-danger, .alert-warning, .alert-info, 
.alert-light, .alert-dark {
    background-color: var(--light-bg);
    background-image: none;
    border: 1px solid var(--light-border);
    color: var(--light-text);
}

[data-bs-theme="dark"] .alert.alert-dismissible,
[data-bs-theme="dark"] .alert.alert-dismissible.rounded-0,
[data-bs-theme="dark"] body .alert.alert-dismissible,
[data-bs-theme="dark"] .alert-primary,
[data-bs-theme="dark"] .alert-secondary,
[data-bs-theme="dark"] .alert-success,
[data-bs-theme="dark"] .alert-danger,
[data-bs-theme="dark"] .alert-warning,
[data-bs-theme="dark"] .alert-info,
[data-bs-theme="dark"] .alert-light,
[data-bs-theme="dark"] .alert-dark {
    background-color: var(--dark-bg);
    background-image: none;
    border: 1px solid var(--dark-border);
    color: var(--dark-text);
}

/* ================================
   导航栏样式 (Navbar Styles)
   ================================ */
.navbar {
    min-height: 50px !important;
    padding: var(--spacing-sm) 0 !important;
}

.navbar-sticky {
    position: fixed !important;
    top: 0 !important;
    left: 0 !important;
    right: 0 !important;
    z-index: 1030 !important;
    width: 100% !important;
}

.navbar-brand {
    padding: var(--spacing-sm) 0 !important;
}

.navbar-brand img {
    width: 120px !important;
    height: 60px !important;
    object-fit: contain !important;
}

.navbar .btn-primary {
    background-color: #040506 !important;
    border-color: #040506 !important;
    font-size: var(--font-lg) !important;
    font-weight: 600 !important;
    padding: var(--spacing-sm) var(--spacing-xl) !important;
}

.navbar .btn-primary:hover {
    background-color: #2a2f3a !important;
    border-color: #2a2f3a !important;
}

.navbar-nav .nav-link,
.navbar-nav .dropdown-toggle {
    padding: var(--spacing-sm) var(--spacing-lg) !important;
    font-size: var(--font-xl) !important;
    font-weight: 700 !important;
}

.navbar-nav .dropdown-item {
    font-size: var(--font-xl) !important;
    font-weight: 700 !important;
    padding: var(--spacing-md) var(--spacing-lg) !important;
}

/* Offcanvas 样式 */
.offcanvas-title {
    font-size: 1.25rem !important;
    font-weight: 700 !important;
}

.offcanvas-body .navbar-nav .nav-link {
    font-size: var(--font-lg) !important;
    font-weight: 600 !important;
    padding: var(--spacing-md) var(--spacing-lg) !important;
}

/* ================================
   面包屑导航样式 (Breadcrumb)
   ================================ */
nav[aria-label="breadcrumb"],
nav.container[aria-label="breadcrumb"] {
    position: relative !important;
    z-index: 10 !important;
    margin-top: var(--spacing-sm) !important;
    background-color: transparent !important;
}

nav[aria-label="breadcrumb"] .breadcrumb,
nav.container[aria-label="breadcrumb"] .breadcrumb {
    position: relative !important;
    z-index: 1 !important;
}

@media (min-width: 992px) {
    nav.container[aria-label="breadcrumb"],
    nav[aria-label="breadcrumb"].container {
        margin-top: var(--spacing-sm) !important;
        margin-bottom: var(--spacing-sm) !important;
        padding-top: 0.25rem !important;
        padding-bottom: 0.25rem !important;
    }
    
    nav.container[aria-label="breadcrumb"] .breadcrumb,
    nav[aria-label="breadcrumb"].container .breadcrumb {
        display: flex;
        flex-wrap: nowrap;
        overflow: hidden;
        width: 100%;
        white-space: nowrap;
    }
    
    nav.container[aria-label="breadcrumb"] .breadcrumb-item:first-child,
    nav[aria-label="breadcrumb"].container .breadcrumb-item:first-child,
    nav.container[aria-label="breadcrumb"] .breadcrumb-item + .breadcrumb-item::before,
    nav[aria-label="breadcrumb"].container .breadcrumb-item + .breadcrumb-item::before {
        flex-shrink: 0;
        white-space: nowrap;
    }
    
    nav.container[aria-label="breadcrumb"] .breadcrumb-item.active,
    nav[aria-label="breadcrumb"].container .breadcrumb-item.active {
        flex: 1 1 0%;
        min-width: 0;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
        max-width: 100%;
    }
}

@media (max-width: 991.98px) {
    nav.container[aria-label="breadcrumb"],
    nav[aria-label="breadcrumb"].container {
        padding-top: var(--spacing-sm) !important;
        padding-bottom: 0 !important;
        margin-top: 0 !important;
        margin-bottom: var(--spacing-sm) !important;
    }
    
    .breadcrumb {
        display: flex;
        flex-wrap: nowrap;
        overflow: hidden;
        width: 100%;
        margin-bottom: 0;
        white-space: nowrap;
    }
    
    .breadcrumb-item {
        flex-shrink: 0;
        white-space: nowrap;
    }
    
    .breadcrumb-item.active {
        flex: 1 1 0%;
        min-width: 0;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
        max-width: 100%;
    }
}

/* ================================
   容器样式 (Container Styles)
   ================================ */
.container-fluid[style*="max-width: 1600px"],
.navbar[style*="max-width: 1600px"] {
    max-width: 1600px !important;
    width: 100% !important;
    margin: 0 auto !important;
}

.container-fluid[style*="max-width: 1600px"] {
    padding: 20px !important;
}

@media (max-width: 1599px) {
    .container-fluid[style*="max-width: 1600px"] {
        max-width: 100% !important;
        padding: 15px !important;
    }
}

@media (max-width: 991.98px) {
    .container-fluid[style*="max-width: 1600px"] {
        padding: 15px 0 !important;
    }
}

/* ================================
   卡片样式 (Card Styles)
   ================================ */
.card-header {
    border-color: var(--light-border);
}

.card-header .form-control {
    border: 1px solid var(--light-border-alt);
    border-radius: 6px;
    font-size: 0.9rem;
    height: 38px;
    transition: all 0.3s ease;
}

.card-header .form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}

.card-body .d-flex.justify-content-between {
    flex-wrap: nowrap;
    gap: var(--spacing-lg);
}

.card-body .d-flex.justify-content-between > div:first-child {
    flex: 1;
    min-width: 0;
}

.card-body .d-flex.justify-content-between > div:last-child {
    flex-shrink: 0;
}

/* 暗黑主题卡片 */
[data-bs-theme="dark"] .card {
    background-color: var(--dark-bg);
    border-color: var(--dark-border);
}

[data-bs-theme="dark"] .card-header {
    background-color: var(--dark-bg-alt);
    border-color: var(--dark-border);
    color: var(--dark-text);
}

[data-bs-theme="dark"] .card-body {
    background-color: var(--dark-bg);
    color: var(--dark-text);
}

[data-bs-theme="dark"] .card-header .form-control {
    background-color: var(--dark-bg-alt);
    border-color: var(--dark-border);
    color: var(--light-bg);
}

[data-bs-theme="dark"] .card-header .form-control:focus {
    background-color: var(--dark-bg-alt);
    border-color: var(--primary-color);
}

[data-bs-theme="dark"] .card-header .form-control::placeholder {
    color: var(--dark-text-alt);
}

/* ================================
   分类列表样式 (Category List)
   ================================ */
.category-children {
    max-height: 0 !important;
    overflow: hidden !important;
    transition: max-height 0.3s ease-in-out;
}

.category-children.expanded {
    max-height: 10000px !important;
}

.category-children.collapsed {
    max-height: 0 !important;
}

.list-group-item {
    border: none;
    border-bottom: 1px solid var(--light-bg-alt);
    background-color: var(--light-bg) !important;
    color: var(--light-text) !important;
}

.list-group-item:hover {
    background-color: var(--light-bg-alt) !important;
    color: var(--light-text) !important;
}

.list-group-item.active {
    background-color: var(--primary-color) !important;
    border-color: var(--primary-color) !important;
    color: white !important;
}

.category-name {
    color: var(--light-text) !important;
    font-weight: 700 !important;
    font-size: var(--font-base) !important;
    margin: 0 !important;
    line-height: 1.2 !important;
}

h5.category-name,
h5.category-count {
    margin: 0 !important;
    padding: 0 !important;
    font-size: var(--font-base) !important;
    line-height: 1.2 !important;
    display: inline !important;
}

.category-count {
    background-color: transparent !important;
    color: var(--light-text-muted) !important;
    font-weight: 700 !important;
    font-size: var(--font-base) !important;
    border: none !important;
    padding: 0 !important;
    margin: 0 !important;
    line-height: 1.2 !important;
}

.list-group-item.active .category-name {
    color: white !important;
    font-weight: 700 !important;
}

.list-group-item.active .category-count {
    background-color: transparent !important;
    color: var(--light-bg) !important;
    border: none !important;
    font-weight: 700 !important;
    font-size: var(--font-base) !important;
}

.list-group-item:not(.active) .category-name {
    color: var(--light-text) !important;
    font-weight: 700 !important;
}

.list-group-item:not(.active) .category-count {
    background-color: transparent !important;
    color: var(--light-text-muted) !important;
    border: none !important;
    font-weight: 700 !important;
    font-size: var(--font-base) !important;
}

/* 暗黑主题分类 */
[data-bs-theme="dark"] .list-group-item {
    border-bottom-color: var(--dark-border) !important;
    background-color: var(--dark-bg) !important;
    color: var(--light-bg) !important;
}

[data-bs-theme="dark"] .list-group-item:hover {
    background-color: var(--dark-bg-alt) !important;
    color: var(--light-bg) !important;
}

[data-bs-theme="dark"] .list-group-item.active {
    background-color: var(--primary-color) !important;
    border-color: var(--primary-color) !important;
    color: white !important;
}

[data-bs-theme="dark"] .category-name {
    color: var(--light-bg) !important;
    font-weight: 700 !important;
}

[data-bs-theme="dark"] .category-count {
    background-color: transparent !important;
    color: var(--dark-text-alt) !important;
    font-weight: 700 !important;
    border: none !important;
}

[data-bs-theme="dark"] .list-group-item.active .category-name {
    color: var(--light-bg) !important;
    font-weight: 700 !important;
}

[data-bs-theme="dark"] .list-group-item.active .category-count {
    background-color: transparent !important;
    color: var(--light-bg) !important;
    border: none !important;
    font-weight: 700 !important;
    font-size: var(--font-base) !important;
}

[data-bs-theme="dark"] .list-group-item:not(.active) .category-name {
    color: var(--light-bg) !important;
    font-weight: 700 !important;
}

[data-bs-theme="dark"] .list-group-item:not(.active) .category-count {
    background-color: transparent !important;
    color: var(--dark-text-alt) !important;
    border: none !important;
    font-weight: 700 !important;
    font-size: var(--font-base) !important;
}

/* 暗黑主题list-group */
[data-bs-theme="dark"] .list-group {
    background-color: var(--dark-bg) !important;
}

[data-bs-theme="dark"] .list-group-flush {
    background-color: transparent !important;
}

/* 暗黑主题卡片列表背景 */
[data-bs-theme="dark"] .card.border-0.bg-light,
[data-bs-theme="dark"] .bg-light {
    background-color: var(--dark-bg) !important;
    color: var(--dark-text) !important;
}

[data-bs-theme="dark"] .card-header.bg-light {
    background-color: var(--dark-bg-alt) !important;
    color: var(--dark-text) !important;
}

[data-bs-theme="dark"] .card-header.bg-light .card-title {
    color: var(--dark-text) !important;
}

[data-bs-theme="dark"] .card-header.bg-light i {
    color: var(--dark-text) !important;
}

[data-bs-theme="dark"] #productSearch {
    background-color: var(--dark-bg-alt);
    border-color: var(--dark-border);
    color: var(--light-bg);
}

[data-bs-theme="dark"] #productSearch:focus {
    background-color: var(--dark-bg-alt);
    border-color: var(--primary-color);
    color: var(--light-bg);
}

[data-bs-theme="dark"] #productSearch::placeholder {
    color: var(--dark-text-alt);
}

/* ================================
   公告内容样式 (Notice Content)
   ================================ */
.notice-content {
    background-color: var(--light-bg-alt);
    border-radius: 8px;
    padding: 20px;
    border-left: 4px solid var(--primary-color);
    margin: 0;
    width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
}

.notice-content p,
.notice-content div,
.notice-content ul,
.notice-content li {
    margin-bottom: 8px;
    line-height: 1.6;
}

.notice-content > *:last-child,
.notice-content ul:last-child li:last-child {
    margin-bottom: 0;
}

[data-bs-theme="dark"] .notice-content {
    background-color: var(--dark-bg-alt);
    color: var(--dark-text);
}

/* ================================
   支付方式样式 (Payment Methods)
   ================================ */
.balance-payment-icon {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 8px;
}

.balance-payment-icon i {
    font-size: 24px;
    color: var(--success-color);
}

.balance-amount {
    font-size: 10px;
    color: var(--success-color);
    margin-top: 1px;
    font-weight: bold;
}

.payment-amount-display {
    color: var(--danger-color);
    font-weight: bold;
}

.payment-method-option {
    cursor: pointer;
    margin: 2px;
}

.payment-method-option .btn {
    border: 2px solid var(--light-border-alt);
    transition: all 0.3s ease;
    width: 50px;
    height: 50px;
    padding: 5px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.payment-method-option .btn:hover,
.payment-method-option input[type="radio"]:checked + .btn {
    border-color: var(--success-color);
    background-color: var(--light-bg-alt);
}

.payment-method-option input[type="radio"]:checked + .btn {
    box-shadow: 0 0 0 0.2rem rgba(40, 167, 69, 0.25);
}

.paymentsvg {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ================================
   产品列表样式 (Product List)
   ================================ */
.product-item {
    margin-bottom: 0;
}

.product-item .card,
.product-item a.card,
.product-item .product-card {
    border-bottom: 1px solid var(--light-border) !important;
    border-radius: 0 !important;
    margin-bottom: 0 !important;
    cursor: pointer !important;
    transition: all 0.3s ease;
}

.product-item:last-child .card,
.product-item:last-child a.card,
.product-item:last-child .product-card {
    border-bottom: none;
}

.product-item .card-body {
    padding: 0.15rem 0.5rem !important;
}

/* 产品卡片 hover 效果 */
.product-item .card:hover,
.product-item a.card:hover,
.product-item .product-card:hover,
.product-item .bg-light:hover {
    background-color: var(--primary-color) !important;
    background: var(--primary-color) !important;
    color: var(--light-bg) !important;
    box-shadow: var(--shadow-sm) !important;
}

.product-item .card:hover *,
.product-item a.card:hover *,
.product-item .product-card:hover *,
.product-item .bg-light:hover * {
    color: var(--light-bg) !important;
}

.product-item .card:hover .badge,
.product-item a.card:hover .badge,
.product-item .product-card:hover .badge,
.product-item .bg-light:hover .badge {
    background-color: var(--light-bg) !important;
    color: var(--primary-color) !important;
}

.product-item .card:hover .text-muted,
.product-item a.card:hover .text-muted,
.product-item .product-card:hover .text-muted,
.product-item .bg-light:hover .text-muted {
    color: #e0e0e0 !important;
}

.product-item h6 {
    margin: 0 !important;
    line-height: 1.2 !important;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    word-break: keep-all;
    word-wrap: normal;
    max-width: 100%;
    flex-shrink: 1;
    min-width: 0;
}

.product-item .d-flex.align-items-center {
    min-height: 38px !important;
}

.product-item .col,
.product-item .d-flex.flex-grow-1 {
    min-width: 0;
    flex-shrink: 1;
}

/* 暗黑主题产品列表 */
[data-bs-theme="dark"] .product-item .card,
[data-bs-theme="dark"] .product-item a.card,
[data-bs-theme="dark"] .product-item .product-card {
    border-bottom-color: var(--dark-border) !important;
    background-color: var(--dark-bg) !important;
}

[data-bs-theme="dark"] .product-item .card.bg-light,
[data-bs-theme="dark"] .product-item a.card.bg-light {
    background-color: var(--dark-bg) !important;
}

[data-bs-theme="dark"] .product-item .card-body {
    background-color: var(--dark-bg) !important;
    color: var(--dark-text) !important;
}

[data-bs-theme="dark"] .product-item .card:hover,
[data-bs-theme="dark"] .product-item a.card:hover,
[data-bs-theme="dark"] .product-item .product-card:hover,
[data-bs-theme="dark"] .product-item .bg-light:hover,
[data-bs-theme="dark"] .product-item .card.bg-light:hover,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover {
    background-color: #409EFF !important;
    background: #409EFF !important;
    background-image: none !important;
    color: #ffffff !important;
    box-shadow: 0 2px 8px rgba(64, 158, 255, 0.4) !important;
}

[data-bs-theme="dark"] .product-item .card:hover .card-body,
[data-bs-theme="dark"] .product-item a.card:hover .card-body,
[data-bs-theme="dark"] .product-item .product-card:hover .card-body,
[data-bs-theme="dark"] .product-item .bg-light:hover .card-body,
[data-bs-theme="dark"] .product-item .card.bg-light:hover .card-body,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover .card-body {
    background-color: #409EFF !important;
    background: #409EFF !important;
    background-image: none !important;
    color: #ffffff !important;
}

[data-bs-theme="dark"] .product-item .card:hover *,
[data-bs-theme="dark"] .product-item a.card:hover *,
[data-bs-theme="dark"] .product-item .product-card:hover *,
[data-bs-theme="dark"] .product-item .bg-light:hover *,
[data-bs-theme="dark"] .product-item .card.bg-light:hover *,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover * {
    color: #ffffff !important;
}

[data-bs-theme="dark"] .product-item .card:hover .badge,
[data-bs-theme="dark"] .product-item a.card:hover .badge,
[data-bs-theme="dark"] .product-item .product-card:hover .badge,
[data-bs-theme="dark"] .product-item .bg-light:hover .badge,
[data-bs-theme="dark"] .product-item .card.bg-light:hover .badge,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover .badge {
    background-color: #ffffff !important;
    color: #409EFF !important;
}

[data-bs-theme="dark"] .product-item .card:hover .text-muted,
[data-bs-theme="dark"] .product-item a.card:hover .text-muted,
[data-bs-theme="dark"] .product-item .product-card:hover .text-muted,
[data-bs-theme="dark"] .product-item .bg-light:hover .text-muted,
[data-bs-theme="dark"] .product-item .card.bg-light:hover .text-muted,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover .text-muted {
    color: #e0e0e0 !important;
}

[data-bs-theme="dark"] .product-item .card:hover .text-danger,
[data-bs-theme="dark"] .product-item a.card:hover .text-danger,
[data-bs-theme="dark"] .product-item .product-card:hover .text-danger,
[data-bs-theme="dark"] .product-item .bg-light:hover .text-danger,
[data-bs-theme="dark"] .product-item .card.bg-light:hover .text-danger,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover .text-danger {
    color: #ffffff !important;
}

[data-bs-theme="dark"] .product-item .card:hover h6,
[data-bs-theme="dark"] .product-item a.card:hover h6,
[data-bs-theme="dark"] .product-item .product-card:hover h6,
[data-bs-theme="dark"] .product-item .bg-light:hover h6,
[data-bs-theme="dark"] .product-item .card.bg-light:hover h6,
[data-bs-theme="dark"] .product-item a.card.bg-light:hover h6 {
    color: #ffffff !important;
}

/* 暗黑主题产品列表 focus/active 状态 */
[data-bs-theme="dark"] .product-item .card:focus,
[data-bs-theme="dark"] .product-item a.card:focus,
[data-bs-theme="dark"] .product-item .card:active,
[data-bs-theme="dark"] .product-item a.card:active,
[data-bs-theme="dark"] .product-item .card.bg-light:focus,
[data-bs-theme="dark"] .product-item a.card.bg-light:focus,
[data-bs-theme="dark"] .product-item .card.bg-light:active,
[data-bs-theme="dark"] .product-item a.card.bg-light:active {
    background-color: #409EFF !important;
    background: #409EFF !important;
    color: #ffffff !important;
    box-shadow: 0 2px 8px rgba(64, 158, 255, 0.4) !important;
}

[data-bs-theme="dark"] .product-item .card:focus *,
[data-bs-theme="dark"] .product-item a.card:focus *,
[data-bs-theme="dark"] .product-item .card:active *,
[data-bs-theme="dark"] .product-item a.card:active *,
[data-bs-theme="dark"] .product-item .card.bg-light:focus *,
[data-bs-theme="dark"] .product-item a.card.bg-light:focus *,
[data-bs-theme="dark"] .product-item .card.bg-light:active *,
[data-bs-theme="dark"] .product-item a.card.bg-light:active * {
    color: #ffffff !important;
}

/* ================================
   回到顶部按钮 (Scroll Top Button)
   ================================ */
.btn-scroll-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 1000;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--primary-color);
    color: white;
    border: none;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    text-decoration: none;
}

.btn-scroll-top:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    color: white;
}

.btn-scroll-top svg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.btn-scroll-top svg rect {
    fill: none;
    stroke: currentColor;
    stroke-width: 1.5;
    stroke-dasharray: 155.201;
    stroke-dashoffset: 155.201;
    transition: stroke-dashoffset 0.3s ease;
}

/* ================================
   响应式布局 - 大屏幕 (Desktop)
   ================================ */
@media (min-width: 992px) {
    section.container[style*="max-width: 1600px"].py-5 {
        padding-top: 0 !important;
        padding-bottom: 1rem !important;
    }
}

/* ================================
   响应式布局 - 平板 (Tablet)
   ================================ */
@media (max-width: 992px) {
    .card-body .d-flex.justify-content-between {
        gap: var(--spacing-sm);
    }
}

@media (max-width: 768px) {
    .card-header.d-flex {
        flex-direction: column;
        align-items: stretch;
        gap: 15px;
    }
    
    .card-header .position-relative {
        max-width: 100%;
        width: 100%;
    }
    
    .card-body .d-flex.justify-content-between:not(.product-first-row):not(.product-detail-header) {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }
    
    .product-detail-header {
        flex-direction: row;
        align-items: center;
        flex-wrap: nowrap;
    }
    
    .product-item .card-body .product-first-row {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
        flex-wrap: nowrap;
    }
}

/* ================================
   响应式布局 - 移动端 (Mobile)
   ================================ */
@media (max-width: 991.98px) {
    .product-item .card-body {
        padding: 0.15rem 0.25rem !important;
        overflow: visible;
    }
    
    section.container[style*="max-width: 1600px"] > .row {
        display: grid;
        grid-template-columns: 1fr;
        grid-template-rows: auto auto auto;
        gap: var(--spacing-lg);
    }
    
    .container-fluid[style*="max-width: 1600px"] > .row {
        display: grid;
        grid-template-columns: 1fr;
        grid-template-rows: auto auto auto;
        gap: var(--spacing-lg);
        padding-left: 15px;
        padding-right: 15px;
    }
    
    /* 移动端分类隐藏 */
    .col-lg-3.col-md-4.mobile-order-2 {
        display: none;
    }
    
    /* 移动端水平导航 */
    .mobile-nav-horizontal {
        display: flex;
        flex-direction: row;
        flex-wrap: nowrap;
        justify-content: space-around;
        align-items: center;
        width: 100%;
        gap: var(--spacing-sm);
        padding: var(--spacing-sm) 0;
        overflow-x: auto;
        overflow-y: hidden;
    }
    
    .nav-link-horizontal {
        flex: 0 0 auto;
        flex-shrink: 0;
        text-align: center;
        padding: var(--spacing-sm) var(--spacing-md);
        color: var(--light-text);
        text-decoration: none;
        font-size: var(--font-base);
        font-weight: 500;
        border-radius: var(--border-radius);
        transition: background-color 0.2s ease;
        white-space: nowrap;
    }
    
    .nav-link-horizontal:hover,
    .nav-link-horizontal:active {
        background-color: var(--light-bg-alt);
    }
    
    .nav-link-horizontal.active {
        background-color: var(--primary-color);
        color: var(--light-bg);
    }
    
    [data-bs-theme="dark"] .nav-link-horizontal {
        color: var(--dark-text);
        background-color: #2b3035;
        border: 1px solid var(--dark-border);
    }
    
    [data-bs-theme="dark"] .nav-link-horizontal:hover,
    [data-bs-theme="dark"] .nav-link-horizontal:active {
        background-color: var(--dark-bg-alt);
        border-color: #6c757d;
    }
    
    [data-bs-theme="dark"] .nav-link-horizontal.active {
        background-color: var(--primary-color);
        color: var(--light-bg);
        border-color: var(--primary-color);
    }
}

/* 移动端产品布局 */
@media (max-width: 767.98px) {
    .product-item .d-md-none.d-flex.align-items-start {
        width: 100%;
        gap: var(--spacing-sm);
        flex-direction: row;
        display: flex;
    }
    
    .product-item .d-md-none img.rounded.flex-shrink-0 {
        width: 32px;
        height: 32px;
        object-fit: cover;
        border-radius: var(--spacing-xs);
        order: -1;
        margin-right: var(--spacing-sm);
        flex-shrink: 0;
        display: block;
    }
    
    .product-item .d-md-none .flex-grow-1 {
        min-width: 0;
        flex: 1;
        overflow: hidden;
    }
    
    .product-item .d-md-none .badge.bg-primary {
        font-size: var(--font-sm);
        padding: 0.2rem 0.4rem;
        line-height: 1.4;
        white-space: nowrap;
        flex-shrink: 0;
    }
    
    .product-item .d-md-none h6.mb-0 {
        white-space: normal;
        word-break: break-word;
        word-wrap: break-word;
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
        overflow: hidden;
        text-overflow: ellipsis;
        flex: 1;
        font-size: 0.875rem;
        line-height: 1.4;
        margin: 0;
        overflow-wrap: break-word;
    }
    
    .product-item .card-body.py-2 {
        padding: 0.3rem !important;
    }
}

@media (max-width: 575.98px) {
    .product-item .d-md-none img.rounded.flex-shrink-0 {
        width: 28px;
        height: 28px;
    }
    
    .product-item .d-md-none .badge.bg-primary {
        font-size: var(--font-xs);
        padding: 0.15rem 0.35rem;
    }
    
    .product-item .d-md-none h6.mb-0 {
        font-size: 0.8125rem;
        line-height: 1.35;
    }
    
    .product-item .card-body.py-2 {
        padding: 0.25rem !important;
    }
}

/* 暗黑主题移动端 */
[data-bs-theme="dark"] .product-item .d-md-none .badge.bg-primary {
    background-color: var(--primary-color);
    color: var(--light-bg);
}

[data-bs-theme="dark"] .product-item .d-md-none .text-muted {
    color: var(--dark-text-alt);
}

[data-bs-theme="dark"] .product-item .d-md-none .fw-bold.text-danger {
    color: #ff6b6b;
}

/* ================================
   移动端分类手风琴 (Mobile Category Accordion)
   ================================ */
@media (max-width: 991.98px) {
    .mobile-category-accordion {
        margin-top: var(--spacing-md);
        padding: 0;
    }
    
    .mobile-category-accordion .category-item {
        width: 100%;
        border-bottom: 1px solid var(--light-border);
    }
    
    .mobile-category-accordion .category-item:last-child {
        border-bottom: none;
    }
    
    .mobile-category-accordion .category-link {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: var(--spacing-md) var(--spacing-lg);
        color: var(--light-text);
        text-decoration: none;
        font-size: 1.05rem;
        font-weight: 500;
        transition: background-color 0.2s ease;
    }
    
    .mobile-category-accordion .category-link:hover,
    .mobile-category-accordion .category-link:active {
        background-color: var(--light-bg-alt);
    }
    
    .mobile-category-accordion .category-parent.expanded .category-arrow {
        transform: rotate(180deg);
    }
    
    .mobile-category-accordion .category-arrow {
        transition: transform 0.3s ease;
        font-size: 0.9rem;
        color: var(--light-text-muted);
    }
    
    .mobile-category-accordion .category-children {
        background-color: var(--light-bg-alt);
        overflow: hidden;
        transition: max-height 0.3s ease;
        max-height: 0;
    }
    
    .mobile-category-accordion .category-children.expanded {
        max-height: 2000px;
    }
    
    .mobile-category-accordion .category-child-link {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 0.65rem var(--spacing-lg);
        color: #495057;
        text-decoration: none;
        font-size: 0.95rem;
        transition: background-color 0.2s ease;
        border-bottom: 1px solid var(--light-border-alt);
    }
    
    .mobile-category-accordion .category-child-link:last-child {
        border-bottom: none;
    }
    
    .mobile-category-accordion .category-child-link:hover,
    .mobile-category-accordion .category-child-link:active {
        background-color: var(--light-border);
    }
    
    /* 暗黑主题 */
    [data-bs-theme="dark"] .mobile-category-accordion .category-item {
        border-bottom-color: var(--dark-border);
    }
    
    [data-bs-theme="dark"] .mobile-category-accordion .category-link {
        color: var(--dark-text);
    }
    
    [data-bs-theme="dark"] .mobile-category-accordion .category-link:hover,
    [data-bs-theme="dark"] .mobile-category-accordion .category-link:active {
        background-color: var(--dark-bg-alt);
    }
    
    [data-bs-theme="dark"] .mobile-category-accordion .category-children {
        background-color: #2b3035;
    }
    
    [data-bs-theme="dark"] .mobile-category-accordion .category-child-link {
        color: var(--dark-text-alt);
        border-bottom-color: var(--dark-border);
    }
    
    [data-bs-theme="dark"] .mobile-category-accordion .category-child-link:hover,
    [data-bs-theme="dark"] .mobile-category-accordion .category-child-link:active {
        background-color: var(--dark-bg-alt);
    }
}

/* ================================
   工具类补充 (Utility Classes)
   ================================ */
@media (max-width: 991.98px) {
    .mobile-order-1 { order: 1; }
    .mobile-order-2 { order: 2; }
    .mobile-order-3 { order: 3; }
}