/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* 导航栏样式 */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 2rem;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand h1 {
    color: #2c3e50;
    font-size: 1.5rem;
    font-weight: 600;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #7f8c8d;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    transition: all 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: #3498db;
    background: rgba(52, 152, 219, 0.1);
}

/* 主容器 */
.container {
    max-width: 1400px;
    margin: 2rem auto;
    padding: 0 2rem;
}

/* 仪表板区域 */
.dashboard-section {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.section-header h2 {
    color: #2c3e50;
    font-size: 2rem;
    font-weight: 600;
}

.controls {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.control-select,
.control-btn {
    padding: 0.5rem 1rem;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    background: white;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.control-select:focus,
.control-btn:hover {
    border-color: #3498db;
    outline: none;
}

.control-btn {
    background: #3498db;
    color: white;
    border: none;
}

.control-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

/* 统计卡片网格 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1.5rem;
    border-radius: 15px;
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
}

.stat-icon {
    font-size: 2.5rem;
}

.stat-content h3 {
    font-size: 0.9rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.stat-value {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-change {
    font-size: 0.8rem;
    padding: 0.2rem 0.5rem;
    border-radius: 15px;
    font-weight: 600;
}

.stat-change.positive {
    background: rgba(46, 204, 113, 0.2);
    color: #27ae60;
}

.stat-change.negative {
    background: rgba(231, 76, 60, 0.2);
    color: #c0392b;
}

/* 图表网格 */
.charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
}

.chart-container {
    background: white;
    padding: 1.5rem;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.chart-container.full-width {
    grid-column: 1 / -1;
}

.chart-container h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
    font-size: 1.2rem;
    font-weight: 600;
}

.chart-container canvas {
    width: 100% !important;
    height: 300px !important;
}

/* 页脚 */
footer {
    text-align: center;
    padding: 2rem;
    color: white;
    background: rgba(0, 0, 0, 0.1);
    margin-top: 2rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        padding: 1rem;
        flex-direction: column;
        gap: 1rem;
    }

    .nav-menu {
        gap: 1rem;
    }

    .container {
        padding: 0 1rem;
        margin: 1rem auto;
    }

    .dashboard-section {
        padding: 1rem;
    }

    .section-header {
        flex-direction: column;
        gap: 1rem;
        align-items: flex-start;
    }

    .charts-grid {
        grid-template-columns: 1fr;
    }

    .chart-container canvas {
        height: 250px !important;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }
}

/* 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); }
}