/* 通用样式 */
* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f5f6fa;
    color: #2c3e50;
    line-height: 1.6;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 10px !important;
    }
    
    .row {
        flex-direction: column !important;
    }
    
    .col-md-4, .col-md-6, .col-md-12 {
        flex: 0 0 100% !important;
    }
    
    .nav a {
        display: block;
        margin-bottom: 0.5rem;
    }
    
    .btn {
        width: 100%;
        margin-bottom: 0.5rem;
    }
    
    .table {
        font-size: 0.8rem;
    }
    
    .modal-content {
        width: 95% !important;
        margin: 10% auto !important;
    }
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: #c1c1c1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #a8a8a8;
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.3s ease-out;
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 工具提示 */
.tooltip {
    position: relative;
    display: inline-block;
}

.tooltip .tooltiptext {
    visibility: hidden;
    width: 120px;
    background-color: #555;
    color: #fff;
    text-align: center;
    border-radius: 6px;
    padding: 5px;
    position: absolute;
    z-index: 1;
    bottom: 125%;
    left: 50%;
    margin-left: -60px;
    opacity: 0;
    transition: opacity 0.3s;
    font-size: 0.8rem;
}

.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}

/* 徽章样式 */
.badge {
    display: inline-block;
    padding: 0.25em 0.4em;
    font-size: 75%;
    font-weight: 700;
    line-height: 1;
    text-align: center;
    white-space: nowrap;
    vertical-align: baseline;
    border-radius: 0.25rem;
}

.badge-primary {
    color: #fff;
    background-color: #3498db;
}

.badge-success {
    color: #fff;
    background-color: #27ae60;
}

.badge-danger {
    color: #fff;
    background-color: #e74c3c;
}

.badge-warning {
    color: #212529;
    background-color: #f39c12;
}

.badge-info {
    color: #fff;
    background-color: #17a2b8;
}

/* 分页样式 */
.pagination {
    display: flex;
    justify-content: center;
    margin-top: 2rem;
}

.pagination a {
    color: #3498db;
    padding: 8px 16px;
    text-decoration: none;
    border: 1px solid #ddd;
    margin: 0 2px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.pagination a:hover {
    background-color: #f5f5f5;
}

.pagination a.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 空状态样式 */
.empty-state {
    text-align: center;
    padding: 3rem;
    color: #6c757d;
}

.empty-state img {
    max-width: 200px;
    opacity: 0.5;
    margin-bottom: 1rem;
}

.empty-state h3 {
    margin-bottom: 0.5rem;
    color: #495057;
}

/* 打印样式 */
@media print {
    .nav, .btn, .modal, .alert {
        display: none !important;
    }
    
    .container {
        max-width: none !important;
        padding: 0 !important;
    }
    
    .card {
        box-shadow: none !important;
        border: 1px solid #ddd !important;
    }
    
    .table {
        font-size: 12px;
    }
}

/* 可访问性改进 */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* 焦点样式 */
button:focus,
input:focus,
select:focus,
textarea:focus {
    outline: 2px solid #3498db;
    outline-offset: 2px;
}

/* 禁用状态 */
.disabled,
button:disabled,
input:disabled,
select:disabled,
textarea:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* 成功/错误状态 */
.is-valid {
    border-color: #27ae60 !important;
}

.is-invalid {
    border-color: #e74c3c !important;
}

.valid-feedback {
    color: #27ae60;
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

.invalid-feedback {
    color: #e74c3c;
    font-size: 0.875rem;
    margin-top: 0.25rem;
}