* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.class-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.chart-container {
    text-align: center;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 10px;
    margin-bottom: 20px;
}

.chart-img {
    max-width: 100%;
    height: auto;
}

.loading, .no-data, .error {
    text-align: center;
    padding: 20px;
    color: #666;
}

.export-btn {
    background-color: #27ae60;
    color: white;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 5px;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 30px;
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

header h1 {
    color: #2c3e50;
    margin-bottom: 10px;
}

.main-nav {
    display: flex;
    justify-content: center;
    margin-bottom: 30px;
    background: white;
    border-radius: 10px;
    padding: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-item {
    padding: 10px 20px;
    text-decoration: none;
    color: #333;
    border-radius: 5px;
    margin: 0 5px;
    transition: all 0.3s ease;
}

.nav-item:hover, .nav-item.active {
    background-color: #3498db;
    color: white;
}

.dashboard {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    border-radius: 10px;
    text-align: center;
}

.stat-card h3 {
    font-size: 14px;
    margin-bottom: 10px;
    opacity: 0.9;
}

.stat-number {
    font-size: 2em;
    font-weight: bold;
}

.quick-actions {
    margin-bottom: 30px;
}

.quick-actions h2 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.action-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    text-align: center;
    transition: all 0.3s ease;
    font-size: 14px;
}

.btn-primary {
    background-color: #3498db;
    color: white;
}

.btn-secondary {
    background-color: #95a5a6;
    color: white;
}

.btn-success {
    background-color: #27ae60;
    color: white;
}

.btn-danger {
    background-color: #e74c3c;
    color: white;
}

.btn-info {
    background-color: #17a2b8;
    color: white;
}

.btn-large {
    padding: 15px 30px;
    font-size: 18px;
}

.btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

.recent-activity h2 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.records-list {
    max-height: 300px;
    overflow-y: auto;
}

.record-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
    border-bottom: 1px solid #eee;
}

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

.student-name {
    font-weight: bold;
}

.call-time {
    color: #7f8c8d;
    font-size: 0.9em;
}

.score-change {
    font-weight: bold;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 0.8em;
}

.score-change.positive {
    background-color: #d4edda;
    color: #155724;
}

.score-change.negative {
    background-color: #f8d7da;
    color: #721c24;
}

/* 点名页面样式 */
.roll-call-interface {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.class-info {
    text-align: center;
    margin-bottom: 30px;
}

.class-info h2 {
    color: #2c3e50;
    margin-bottom: 10px;
}

.roll-call-result {
    text-align: center;
    margin-bottom: 30px;
}

.student-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px;
    border-radius: 15px;
    margin-bottom: 20px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.student-card h3 {
    font-size: 2em;
    margin-bottom: 10px;
}

.hidden {
    display: none;
}

.score-actions {
    margin-bottom: 30px;
}

.score-actions h3 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.recent-calls h3 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.calls-list {
    max-height: 200px;
    overflow-y: auto;
}

.call-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 8px 12px;
    border-bottom: 1px solid #eee;
}

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

.back-link {
    color: #3498db;
    text-decoration: none;
    margin-top: 10px;
    display: inline-block;
}

.back-link:hover {
    text-decoration: underline;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .action-buttons {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
}
/* 积分页面样式 */
.scores-container {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.class-filter {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.ranking-table table {
    width: 100%;
    border-collapse: collapse;
}

.ranking-table th, .ranking-table td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #eee;
}

.ranking-table th {
    background-color: #f8f9fa;
    font-weight: bold;
}

.ranking-table .rank {
    font-weight: bold;
    color: #3498db;
}

.ranking-table .score.positive {
    color: #27ae60;
    font-weight: bold;
}

.ranking-table .score.negative {
    color: #e74c3c;
    font-weight: bold;
}