/* 全局样式 */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* 导航栏样式 */
.navbar {
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar-brand {
    font-weight: bold;
    font-size: 1.5rem;
}

/* 图表卡片样式 */
.chart-card {
    border: none;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border-radius: 15px;
    overflow: hidden;
}

.chart-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.chart-card .card-header {
    border: none;
    padding: 1rem 1.5rem;
    font-weight: 600;
    background: linear-gradient(45deg, var(--bs-primary) 0%, var(--bs-info) 100%);
}

.chart-card .card-body {
    padding: 2rem;
    background: white;
}

/* 主标题样式 */
h1 {
    color: white;
    font-weight: bold;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
    margin-bottom: 1rem;
}

/* 统计卡片样式 */
.card.bg-primary, .card.bg-success, .card.bg-info, .card.bg-warning {
    border: none;
    transition: transform 0.3s ease;
}

.card.bg-primary:hover, .card.bg-success:hover, 
.card.bg-info:hover, .card.bg-warning:hover {
    transform: scale(1.05);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container-fluid {
        padding: 0 10px;
    }
    
    .chart-card .card-body {
        padding: 1rem;
    }
    
    #kochSnowflake {
        width: 100% !important;
        height: 300px !important;
    }
}

/* Canvas 容器样式 */
canvas {
    max-width: 100%;
    height: auto !important;
}

/* 页脚样式 */
footer {
    margin-top: 3rem !important;
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(0,0,0,.1);
    border-radius: 50%;
    border-top-color: #007bff;
    animation: spin 1s ease-in-out infinite;
}

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

/* 工具提示样式 */
.tooltip {
    font-size: 0.875rem;
}

/* 自定义滚动条 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}

/* 数据标签样式 */
.data-label {
    font-size: 0.85rem;
    color: #666;
    margin-top: 0.5rem;
}

/* 动画效果 */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 图例样式 */
.legend-item {
    margin: 0 10px;
    font-size: 0.9rem;
}

/* 标题修饰 */
.card-header h5 {
    margin: 0;
    display: flex;
    align-items: center;
    gap: 8px;
}