/* 练习中心页面样式 */
#practice-center-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.page-header {
    text-align: center;
    margin-bottom: 40px;
}

.page-header h2 {
    color: var(--primary);
    font-size: var(--text-3xl);
    margin-bottom: 10px;
}

.page-header p {
    color: var(--text-secondary);
    font-size: var(--text-lg);
}

/* 当前选择显示 */
.current-selection {
    background: rgba(58, 91, 201, 0.1);
    padding: 20px;
    border-radius: var(--border-radius);
    margin: 30px 0;
    display: flex;
    align-items: center;
    gap: 15px;
    border-left: 4px solid var(--primary);
}

.current-selection i {
    color: var(--primary);
    font-size: 1.8rem;
}

.current-selection h4 {
    color: var(--primary);
    margin-bottom: 5px;
}

.current-selection p {
    color: var(--text-secondary);
    margin: 0;
}

.change-subject-btn {
    margin-left: auto;
    color: var(--primary);
    border-color: var(--primary);
}

.change-subject-btn:hover {
    background: var(--primary);
    color: white;
}

/* 练习容器 */
.practice-container {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

/* 练习部分 */
.practice-section {
    background: white;
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--box-shadow);
}

.section-title {
    font-size: 1.5rem;
    color: var(--primary);
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 2px solid #f0f0f0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.section-title i {
    font-size: 1.3rem;
}

/* 练习模式网格 */
.practice-modes {
    display: grid;
    gap: 25px;
    margin: 20px 0;
}

.practice-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 30px;
    text-align: center;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
    cursor: pointer;
    border: 2px solid transparent;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.practice-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
    border-color: var(--primary);
}

.practice-icon {
    font-size: 3.5rem;
    color: var(--primary);
    margin-bottom: 20px;
}

.practice-card h3 {
    margin-bottom: 15px;
    color: var(--primary);
    font-size: var(--text-xl);
}

.practice-card p {
    color: var(--text-secondary);
    margin-bottom: 25px;
    flex: 1;
}

.feature-list {
    text-align: left;
    margin: 20px 0;
    list-style: none;
    flex: 1;
}

.feature-list li {
    padding: 8px 0;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
}

.feature-list i {
    color: var(--primary);
    width: 20px;
}

.start-practice-btn {
    margin-top: auto;
    width: 100%;
}

/* 分界线 */
.divider {
    height: 1px;
    background: linear-gradient(to right, transparent, #ddd, transparent);
    margin: 30px 0;
}

/* 统计网格 */
.stats-grid {
    display: grid;
    gap: 20px;
    margin: 20px 0;
}

.stat-card {
    background: white;
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
    transition: var(--transition);
    border-top: 4px solid var(--primary);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
}

.stat-icon {
    margin-bottom: 15px;
}

.stat-icon.fa-clipboard-list { color: var(--primary); }
.stat-icon.fa-check-circle { color: var(--success); }
.stat-icon.fa-trophy { color: var(--warning); }
.stat-icon.fa-clock { color: var(--info); }

.stat-number {
    font-size: var(--text-3xl);
    font-weight: bold;
    color: var(--primary);
    margin: 15px 0;
}

.stat-title {
    color: var(--text-secondary);
    font-size: var(--text-base);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .current-selection {
        flex-direction: column;
        text-align: center;
        gap: 15px;
    }
    
    .change-subject-btn {
        margin-left: 0;
        width: 100%;
    }
    
    .practice-modes {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .practice-section {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .practice-card {
        padding: 20px;
    }
}