/* Apple Design 风格 CSS */

/* 全局样式 */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: #f5f5f7;
    color: #1d1d1f;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

/* 间距类 */
.mb-16 {
    margin-bottom: 1rem !important;
}

.mb-12 {
    margin-bottom: 3rem !important;
}

.mb-8 {
    margin-bottom: 2rem !important;
}

.mb-6 {
    margin-bottom: 1.5rem !important;
}

.py-8 {
    padding-top: 2rem !important;
    padding-bottom: 2rem !important;
}

.py-12 {
    padding-top: 3rem !important;
    padding-bottom: 3rem !important;
}

.p-12 {
    padding: 3rem !important;
}

.p-8 {
    padding: 2rem !important;
}

.p-6 {
    padding: 1.5rem !important;
}

.p-4 {
    padding: 1rem !important;
}

.gap-8 {
    gap: 2rem !important;
}

.gap-6 {
    gap: 1.5rem !important;
}

.gap-4 {
    gap: 1rem !important;
}

/* 区域间距 */
section {
    margin-bottom: 4rem;
}

section:last-child {
    margin-bottom: 0;
}

/* 容器样式 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 卡片样式 */
.card {
    background-color: #ffffff;
    border: none;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    overflow: hidden;
}

.card:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    transform: translateY(-2px);
}

.card-body {
    padding: 24px;
}

.card-title {
    font-weight: 600;
    font-size: 1.25rem;
    margin-bottom: 16px;
    color: #1d1d1f;
}

.card-text {
    color: #6e6e73;
}

/* 按钮样式 */
.btn {
    font-weight: 500;
    border-radius: 8px;
    padding: 10px 20px;
    transition: all 0.2s ease;
    border: none;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.btn-primary {
    background-color: #0071e3;
    color: white;
}

.btn-primary:hover {
    background-color: #0077ed;
    box-shadow: 0 4px 12px rgba(0, 113, 227, 0.3);
    transform: translateY(-1px);
}

.btn-primary:active {
    background-color: #005bb5;
    transform: translateY(0);
}

.btn-secondary {
    background-color: #f5f5f7;
    color: #1d1d1f;
}

.btn-secondary:hover {
    background-color: #ececec;
}

.btn-danger {
    background-color: #ff3b30;
    color: white;
}

.btn-danger:hover {
    background-color: #ff453a;
    box-shadow: 0 4px 12px rgba(255, 59, 48, 0.3);
    transform: translateY(-1px);
}

/* 导航栏样式 */
.navbar {
    background-color: #0071e3;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    padding: 12px 0;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

/* 为页面内容添加顶部间距，避免被固定导航栏遮挡 */
body {
    padding-top: 70px;
}

/* 后台固定侧边栏样式 */
.admin-container {
    display: flex;
    min-height: calc(100vh - 70px);
    margin-top: none;
    overflow: hidden;
}

.admin-sidebar {
    width: 250px;
    background-color: #ffffff;
    border-right: 1px solid rgba(0, 0, 0, 0.1);
    position: fixed;
    top: 70px;
    left: 0;
    bottom: 0;
    overflow-y: auto;
    box-shadow: 1px 0 3px rgba(0, 0, 0, 0.05);
    z-index: 999;
}

.admin-content {
    flex: 1;
    margin-left: 250px;
    padding: 20px;
    background-color: #f5f5f7;
    min-height: calc(100vh - 70px);
    overflow-y: auto;
    box-sizing: border-box;
    width: calc(100% - 250px);
}

/* 移动端调整 */
@media (max-width: 991px) {
    .admin-content {
        margin-left: 0;
        width: 100%;
        padding: 15px;
        overflow-x: hidden;
    }
    
    /* 确保内容容器不会被表格撑开 */
    .admin-content > * {
        max-width: 100%;
        box-sizing: border-box;
    }
    
    /* 确保卡片容器不会被表格撑开 */
    .card {
        max-width: 100%;
        box-sizing: border-box;
        overflow: hidden;
    }
    
    .card-body {
        max-width: 100%;
        box-sizing: border-box;
    }
}

/* 侧边栏列表组样式 */
.admin-sidebar .list-group {
    border-radius: 0;
    box-shadow: none;
}

.admin-sidebar .list-group-item {
    border-radius: 0;
    border-left: 3px solid transparent;
}

.admin-sidebar .list-group-item.active {
    background-color: rgba(0, 113, 227, 0.1);
    border-left-color: #0071e3;
    color: #0071e3;
}

/* 响应式调整 */
@media (max-width: 1024px) {
    .admin-sidebar {
        width: 250px;
        transform: translateX(-100%);
        transition: transform 0.3s ease;
    }
    
    .admin-sidebar.show {
        transform: translateX(0);
    }
    
    .admin-content {
        margin-left: 0;
        width: 100%;
    }
}

/* 移动端进一步优化 */
@media (max-width: 768px) {
    .admin-sidebar {
        width: 100%;
    }
}

.navbar-brand {
    font-weight: 600;
    font-size: 1.25rem;
    color: white;
    text-decoration: none;
}

.navbar-brand:hover {
    color: white;
    text-decoration: none;
}

.navbar-nav .nav-link {
    color: white;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.navbar-nav .nav-link:hover {
    background-color: rgba(255, 255, 255, 0.15);
    color: white;
}

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

/* 导航栏切换按钮 */
.navbar-toggler {
    border-color: rgba(255, 255, 255, 0.2);
}

.navbar-toggler:hover,
.navbar-toggler:focus {
    border-color: white;
    outline: none;
    box-shadow: 0 0 0 0.25rem rgba(255, 255, 255, 0.25);
}

.navbar-toggler-icon {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba%28255, 255, 255, 0.8%29' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

/* 表单样式 */
.form-control {
    border: 1px solid rgba(0, 0, 0, 0.2);
    border-radius: 8px;
    padding: 10px 12px;
    font-size: 1rem;
    transition: all 0.2s ease;
    background-color: #ffffff;
}

.form-control:focus {
    border-color: #0071e3;
    box-shadow: 0 0 0 3px rgba(0, 113, 227, 0.1);
    outline: none;
}

.form-label {
    font-weight: 500;
    color: #1d1d1f;
    margin-bottom: 8px;
}

.form-check-input {
    width: 18px;
    height: 18px;
    margin-top: 4px;
}

.form-check-label {
    color: #6e6e73;
    margin-left: 8px;
}

/* 表格样式 */
.table {
    border-collapse: separate;
    border-spacing: 0;
    background-color: #ffffff;
    border-radius: 12px;
    overflow: visible;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    table-layout: auto;
}

.table th {
    background-color: #f5f5f7;
    font-weight: 600;
    color: #1d1d1f;
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    white-space: nowrap;
}

.table td {
    padding: 12px 16px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    color: #1d1d1f;
    white-space: nowrap;
}

.table tbody tr:hover {
    background-color: rgba(0, 0, 0, 0.02);
}

.table tbody tr:last-child td {
    border-bottom: none;
}

/* 表格响应式样式 - 添加水平滚动条 */
.table-responsive {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin-bottom: 1rem;
    display: block;
    max-width: 100%;
    box-sizing: border-box;
}

/* 优化移动端表格滚动体验 */
@media (max-width: 768px) {
    .table-responsive {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        scrollbar-width: thin;
        scrollbar-color: rgba(0, 113, 227, 0.5) transparent;
    }
    
    /* 为表格添加最小宽度，确保内容完整显示 */
    .table-responsive table {
        min-width: 600px;
        box-sizing: border-box;
    }
    
    /* 优化表格单元格内边距，减少移动端拥挤感 */
    .table-responsive td,
    .table-responsive th {
        padding: 8px 12px;
        font-size: 0.875rem;
    }
    
    /* 确保表格容器不会超出父元素宽度 */
    .table-responsive {
        width: 100%;
        margin-left: 0;
        margin-right: 0;
    }
}

/* 徽章样式 */
.badge {
    border-radius: 12px;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 500;
}

.badge-success {
    background-color: #34c759;
    color: white;
}

.badge-danger {
    background-color: #ff3b30;
    color: white;
}

.badge-warning {
    background-color: #ff9500;
    color: white;
}

/* 统计卡片样式 */
.card.bg-primary,
.card.bg-success,
.card.bg-warning,
.card.bg-danger {
    color: white;
    border: none;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.card.bg-primary .card-title,
.card.bg-success .card-title,
.card.bg-warning .card-title,
.card.bg-danger .card-title {
    color: white;
    opacity: 0.9;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 8px;
}

.card.bg-primary .card-text,
.card.bg-success .card-text,
.card.bg-warning .card-text,
.card.bg-danger .card-text {
    color: white;
    font-size: 2rem;
    font-weight: 600;
}

/* 统计卡片容器 - 移动端紧凑并排显示 */
.stats-cards-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 12px;
    margin-bottom: 20px;
    width: 100%;
}

.stats-cards-container .card {
    flex: 1;
    min-width: 0;
    border-radius: 12px;
    overflow: hidden;
}

/* 优化统计卡片内部样式 */
.stats-cards-container .card-body {
    padding: 12px;
    text-align: center;
}

.stats-cards-container .card-title {
    font-size: 0.75rem;
    margin-bottom: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.stats-cards-container .card-text {
    font-size: 1.25rem;
    font-weight: 600;
    line-height: 1;
    margin: 0;
}

/* 确保在各种屏幕尺寸下都能紧凑显示 */
@media (max-width: 1024px) {
    .stats-cards-container {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (max-width: 768px) {
    .stats-cards-container {
        grid-template-columns: repeat(4, 1fr);
        gap: 8px;
    }
    
    .stats-cards-container .card-body {
        padding: 10px;
    }
    
    .stats-cards-container .card-title {
        font-size: 0.6875rem;
    }
    
    .stats-cards-container .card-text {
        font-size: 1.125rem;
    }
}

@media (max-width: 480px) {
    .stats-cards-container {
        grid-template-columns: repeat(4, 1fr);
        gap: 6px;
    }
    
    .stats-cards-container .card-body {
        padding: 8px;
    }
    
    .stats-cards-container .card-title {
        font-size: 0.625rem;
    }
    
    .stats-cards-container .card-text {
        font-size: 1rem;
    }
}

/* 关键链接样式 - 一排显示 */
.key-links-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    margin-top: 16px;
    width: 100%;
}

.key-link-card {
    background-color: #ffffff;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: all 0.2s ease;
}

.key-link-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.key-link-content {
    padding: 16px;
    text-align: center;
}

.key-link-title {
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: #1d1d1f;
}

.key-link-text {
    font-size: 0.75rem;
    color: #6e6e73;
    margin-bottom: 12px;
    line-height: 1.4;
}

.key-link-card .btn {
    font-size: 0.75rem;
    padding: 6px 12px;
    border-radius: 8px;
}

/* 关键链接响应式设计 */
@media (max-width: 1024px) {
    .key-links-container {
        grid-template-columns: repeat(3, 1fr);
        gap: 12px;
    }
    
    .key-link-content {
        padding: 12px;
    }
    
    .key-link-title {
        font-size: 0.8125rem;
    }
    
    .key-link-text {
        font-size: 0.71875rem;
        margin-bottom: 10px;
    }
}

@media (max-width: 768px) {
    .key-links-container {
        grid-template-columns: repeat(3, 1fr);
        gap: 10px;
    }
    
    .key-link-content {
        padding: 10px;
    }
    
    .key-link-title {
        font-size: 0.75rem;
        margin-bottom: 6px;
    }
    
    .key-link-text {
        font-size: 0.6875rem;
        margin-bottom: 8px;
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
        overflow: hidden;
        text-overflow: ellipsis;
    }
    
    .key-link-card .btn {
        font-size: 0.71875rem;
        padding: 5px 10px;
    }
}

@media (max-width: 480px) {
    .key-links-container {
        grid-template-columns: repeat(3, 1fr);
        gap: 8px;
    }
    
    .key-link-content {
        padding: 8px;
    }
    
    .key-link-title {
        font-size: 0.71875rem;
        margin-bottom: 4px;
    }
    
    .key-link-text {
        font-size: 0.625rem;
        margin-bottom: 6px;
        -webkit-line-clamp: 1;
    }
    
    .key-link-card .btn {
        font-size: 0.6875rem;
        padding: 4px 8px;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .card-body {
        padding: 16px;
    }
    
    .navbar-nav .nav-link {
        padding: 8px;
    }
    
    .table th,
    .table td {
        padding: 8px 12px;
        font-size: 0.875rem;
    }
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card {
    animation: fadeIn 0.3s ease;
}

/* 辅助类 */
.text-center {
    text-align: center;
}

.mb-4 {
    margin-bottom: 1.5rem;
}

.mt-4 {
    margin-top: 1.5rem;
}

.p-4 {
    padding: 1.5rem;
}

.shadow-sm {
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

/* 按钮组样式 */
.btn-group .btn {
    border-radius: 0;
}

.btn-group .btn:first-child {
    border-top-left-radius: 8px;
    border-bottom-left-radius: 8px;
}

.btn-group .btn:last-child {
    border-top-right-radius: 8px;
    border-bottom-right-radius: 8px;
}

/* 输入组样式 */
.input-group .form-control {
    border-right: none;
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
}

.input-group .btn {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
}

/* 列表组样式 */
.list-group {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.list-group-item {
    border: none;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    padding: 12px 16px;
    transition: all 0.2s ease;
}

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

.list-group-item:hover {
    background-color: rgba(0, 0, 0, 0.02);
}

.list-group-item.active {
    background-color: rgba(0, 113, 227, 0.1);
    color: #0071e3;
    font-weight: 500;
}

/* 分页样式 */
.pagination {
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.pagination .page-item .page-link {
    border: none;
    color: #1d1d1f;
    padding: 8px 16px;
    transition: all 0.2s ease;
}

.pagination .page-item .page-link:hover {
    background-color: rgba(0, 0, 0, 0.05);
    color: #0071e3;
}

.pagination .page-item.active .page-link {
    background-color: #0071e3;
    color: white;
}

/* 模态框样式 */
.modal-content {
    border-radius: 12px;
    border: none;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
}

.modal-header {
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    padding: 20px 24px;
}

.modal-title {
    font-weight: 600;
    color: #1d1d1f;
}

.modal-body {
    padding: 24px;
}

.modal-footer {
    border-top: 1px solid rgba(0, 0, 0, 0.1);
    padding: 20px 24px;
}

/* 提示框样式 */
.alert {
    border: none;
    border-radius: 8px;
    padding: 16px 20px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.alert-success {
    background-color: rgba(52, 199, 89, 0.1);
    color: #34c759;
}

.alert-danger {
    background-color: rgba(255, 59, 48, 0.1);
    color: #ff3b30;
}

.alert-warning {
    background-color: rgba(255, 149, 0, 0.1);
    color: #ff9500;
}

.alert-info {
    background-color: rgba(52, 199, 89, 0.1);
    color: #0071e3;
}

/* 代码块样式 */
pre {
    background-color: #f5f5f7;
    border-radius: 8px;
    padding: 16px;
    overflow-x: auto;
    font-family: 'SF Mono', Monaco, Inconsolata, 'Roboto Mono', Consolas, 'Courier New', Courier, monospace;
    font-size: 0.875rem;
    line-height: 1.5;
    color: #1d1d1f;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

code {
    background-color: rgba(0, 0, 0, 0.05);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'SF Mono', Monaco, Inconsolata, 'Roboto Mono', Consolas, 'Courier New', Courier, monospace;
    font-size: 0.875rem;
    color: #ff3b30;
}

pre code {
    background-color: transparent;
    padding: 0;
    color: #1d1d1f;
}

/* 页脚样式 */
footer {
    background-color: #f5f5f7;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
    padding: 24px 0;
    margin-top: 48px;
    color: #6e6e73;
    font-size: 0.875rem;
}

/* 标题样式 */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 1rem;
}

h1 {
    font-size: 2rem;
}

h2 {
    font-size: 1.75rem;
}

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

/* 链接样式 */
a {
    color: #0071e3;
    text-decoration: none;
    transition: all 0.2s ease;
}

a:hover {
    color: #0077ed;
    text-decoration: underline;
}

/* 图片样式 */
img {
    border-radius: 8px;
    max-width: 100%;
    height: auto;
}

/* 分隔线样式 */
hr {
    border-top: 1px solid rgba(0, 0, 0, 0.1);
    margin: 24px 0;
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(0, 0, 0, 0.1);
    border-radius: 50%;
    border-top-color: #0071e3;
    animation: spin 1s ease-in-out infinite;
}

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

/* 隐藏类 */
.hidden {
    display: none;
}

/* 显示类 */
.visible {
    display: block;
}

/* 浮动类 */
.float-left {
    float: left;
}

.float-right {
    float: right;
}

.clearfix::after {
    content: "";
    clear: both;
    display: table;
}

/* 文本对齐类 */
.text-left {
    text-align: left;
}

.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

/* 文本颜色类 */
.text-primary {
    color: #0071e3;
}

.text-success {
    color: #34c759;
}

.text-danger {
    color: #ff3b30;
}

.text-warning {
    color: #ff9500;
}

.text-muted {
    color: #6e6e73;
}

/* 背景颜色类 */
.bg-primary {
    background-color: #0071e3;
}

.bg-success {
    background-color: #34c759;
}

.bg-danger {
    background-color: #ff3b30;
}

.bg-warning {
    background-color: #ff9500;
}

.bg-light {
    background-color: #f5f5f7;
}

.bg-dark {
    background-color: #1d1d1f;
}

/* 边距类 */
.m-0 {
    margin: 0;
}

.mt-0 {
    margin-top: 0;
}

.mb-0 {
    margin-bottom: 0;
}

.ml-0 {
    margin-left: 0;
}

.mr-0 {
    margin-right: 0;
}

.p-0 {
    padding: 0;
}

.pt-0 {
    padding-top: 0;
}

.pb-0 {
    padding-bottom: 0;
}

.pl-0 {
    padding-left: 0;
}

.pr-0 {
    padding-right: 0;
}

/* 宽度类 */
.w-100 {
    width: 100%;
}

.w-50 {
    width: 50%;
}

.w-auto {
    width: auto;
}

/* 高度类 */
.h-100 {
    height: 100%;
}

.h-auto {
    height: auto;
}

/* 溢出类 */
.overflow-hidden {
    overflow: hidden;
}

.overflow-auto {
    overflow: auto;
}

.overflow-x-auto {
    overflow-x: auto;
}

.overflow-y-auto {
    overflow-y: auto;
}

/* 定位类 */
.position-relative {
    position: relative;
}

.position-absolute {
    position: absolute;
}

.position-fixed {
    position: fixed;
}

.position-sticky {
    position: sticky;
}

/* 显示类 */
.d-block {
    display: block;
}

.d-inline {
    display: inline;
}

.d-inline-block {
    display: inline-block;
}

.d-flex {
    display: flex;
}

.d-none {
    display: none;
}

/* Flexbox 类 */
.flex-row {
    flex-direction: row;
}

.flex-column {
    flex-direction: column;
}

.justify-content-start {
    justify-content: flex-start;
}

.justify-content-end {
    justify-content: flex-end;
}

.justify-content-center {
    justify-content: center;
}

.justify-content-between {
    justify-content: space-between;
}

.justify-content-around {
    justify-content: space-around;
}

.align-items-start {
    align-items: flex-start;
}

.align-items-end {
    align-items: flex-end;
}

.align-items-center {
    align-items: center;
}

.align-items-baseline {
    align-items: baseline;
}

.align-items-stretch {
    align-items: stretch;
}

.flex-wrap {
    flex-wrap: wrap;
}

.flex-nowrap {
    flex-wrap: nowrap;
}

/* 响应式显示类 */
@media (max-width: 576px) {
    .d-sm-none {
        display: none;
    }
    
    .d-sm-block {
        display: block;
    }
}

@media (max-width: 768px) {
    .d-md-none {
        display: none;
    }
    
    .d-md-block {
        display: block;
    }
}

@media (max-width: 992px) {
    .d-lg-none {
        display: none;
    }
    
    .d-lg-block {
        display: block;
    }
}

@media (max-width: 1200px) {
    .d-xl-none {
        display: none;
    }
    
    .d-xl-block {
        display: block;
    }
}

/* 响应式 Flexbox 类 */
@media (max-width: 576px) {
    .flex-sm-column {
        flex-direction: column;
    }
    
    .justify-content-sm-center {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    .flex-md-column {
        flex-direction: column;
    }
    
    .justify-content-md-center {
        justify-content: center;
    }
}

@media (max-width: 992px) {
    .flex-lg-column {
        flex-direction: column;
    }
    
    .justify-content-lg-center {
        justify-content: center;
    }
}

@media (max-width: 1200px) {
    .flex-xl-column {
        flex-direction: column;
    }
    
    .justify-content-xl-center {
        justify-content: center;
    }
}

/* 响应式边距类 */
@media (max-width: 576px) {
    .mb-sm-4 {
        margin-bottom: 1.5rem;
    }
    
    .mt-sm-4 {
        margin-top: 1.5rem;
    }
}

@media (max-width: 768px) {
    .mb-md-4 {
        margin-bottom: 1.5rem;
    }
    
    .mt-md-4 {
        margin-top: 1.5rem;
    }
}

@media (max-width: 992px) {
    .mb-lg-4 {
        margin-bottom: 1.5rem;
    }
    
    .mt-lg-4 {
        margin-top: 1.5rem;
    }
}

@media (max-width: 1200px) {
    .mb-xl-4 {
        margin-bottom: 1.5rem;
    }
    
    .mt-xl-4 {
        margin-top: 1.5rem;
    }
}