/* 老师管理后台样式 - 暗色星空主题 */

/* 星空背景动画 */
@keyframes twinkle {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 1; }
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
}

.teacher-dashboard {
    display: flex;
    min-height: 100vh;
    background: linear-gradient(135deg, #0c0c0c 0%, #1a1a2e 50%, #16213e 100%);
    position: relative;
    overflow: hidden;
}

/* 星空背景效果 */
.teacher-dashboard::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        radial-gradient(2px 2px at 20px 30px, #eee, transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.8), transparent),
        radial-gradient(1px 1px at 90px 40px, #fff, transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(255,255,255,0.6), transparent),
        radial-gradient(2px 2px at 160px 30px, #ddd, transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: twinkle 4s ease-in-out infinite;
    pointer-events: none;
    z-index: 1;
}

.teacher-dashboard::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        radial-gradient(1px 1px at 50px 50px, #4a90e2, transparent),
        radial-gradient(1px 1px at 100px 100px, #7b68ee, transparent),
        radial-gradient(1px 1px at 150px 25px, #9370db, transparent);
    background-repeat: repeat;
    background-size: 150px 150px;
    animation: float 6s ease-in-out infinite;
    pointer-events: none;
    z-index: 1;
}

/* 老师等级徽章 */
.teacher-level-info {
    margin-right: 15px;
}

.level-badge {
    display: inline-block;
    padding: 6px 12px;
    background: linear-gradient(135deg, #28a745, #20c997);
    color: white;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    box-shadow: 0 2px 8px rgba(40, 167, 69, 0.3);
}

.level-badge.lv3 {
    background: linear-gradient(135deg, #ffc107, #ff9800);
    box-shadow: 0 2px 8px rgba(255, 193, 7, 0.3);
}

/* 侧边栏 */
.sidebar {
    width: 250px;
    background: linear-gradient(180deg, rgba(20, 20, 40, 0.95) 0%, rgba(30, 30, 60, 0.9) 100%);
    color: #e8e8e8;
    display: flex;
    flex-direction: column;
    box-shadow: 2px 0 20px rgba(0,0,0,0.5);
    backdrop-filter: blur(10px);
    border-right: 1px solid rgba(255,255,255,0.1);
    position: relative;
    z-index: 10;
}

.sidebar-header {
    padding: 20px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    background: linear-gradient(135deg, rgba(100, 100, 200, 0.2), rgba(150, 100, 200, 0.1));
}

.sidebar-header h2 {
    margin: 0;
    font-size: 18px;
    font-weight: 600;
    color: #ffffff;
    text-shadow: 0 0 10px rgba(255,255,255,0.3);
}

.sidebar-header i {
    margin-right: 10px;
    color: #ffd700;
    text-shadow: 0 0 5px rgba(255,215,0,0.5);
}

.sidebar-nav {
    flex: 1;
    padding: 20px 0;
}

.sidebar-nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.nav-item {
    display: flex;
    align-items: center;
    padding: 15px 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 3px solid transparent;
    color: #e8e8e8;
    position: relative;
}

.nav-item:hover {
    background: linear-gradient(90deg, rgba(100, 100, 200, 0.2), rgba(150, 100, 200, 0.1));
    border-left-color: #ffd700;
    color: #ffffff;
    text-shadow: 0 0 5px rgba(255,255,255,0.3);
}

.nav-item.active {
    background: linear-gradient(90deg, rgba(100, 100, 200, 0.3), rgba(150, 100, 200, 0.2));
    border-left-color: #ffd700;
    color: #ffffff;
    text-shadow: 0 0 8px rgba(255,255,255,0.4);
}

.nav-item i {
    margin-right: 12px;
    width: 20px;
    text-align: center;
    color: #b8b8b8;
    transition: color 0.3s ease;
}

.nav-item:hover i,
.nav-item.active i {
    color: #ffd700;
    text-shadow: 0 0 5px rgba(255,215,0,0.5);
}

.sidebar-footer {
    padding: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* 主内容区 */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
    z-index: 5;
}

/* 头部 */
.header {
    background: linear-gradient(135deg, rgba(20, 20, 40, 0.95), rgba(30, 30, 60, 0.9));
    padding: 20px 30px;
    box-shadow: 0 2px 20px rgba(0,0,0,0.3);
    display: flex;
    justify-content: space-between;
    align-items: center;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.header-left h1 {
    margin: 0;
    font-size: 24px;
    color: #ffffff;
    text-shadow: 0 0 10px rgba(255,255,255,0.3);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 10px;
    color: #e8e8e8;
}

.user-info i {
    font-size: 24px;
    color: #b8b8b8;
}

/* 内容区域 */
.content {
    flex: 1;
    padding: 30px;
    background: rgba(10, 10, 20, 0.3);
    backdrop-filter: blur(5px);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* 统计卡片 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: linear-gradient(135deg, rgba(30, 30, 60, 0.8), rgba(40, 40, 80, 0.6));
    padding: 25px;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    border: 1px solid rgba(255,255,255,0.1);
    backdrop-filter: blur(10px);
    display: flex;
    align-items: center;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, #4a90e2, #7b68ee, #9370db);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0,0,0,0.4);
    border-color: rgba(255,255,255,0.2);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 20px;
    font-size: 24px;
    color: white;
    background: linear-gradient(135deg, #4a90e2, #7b68ee);
    box-shadow: 0 4px 15px rgba(74, 144, 226, 0.3);
    text-shadow: 0 0 10px rgba(255,255,255,0.3);
}

.stat-info h3 {
    margin: 0 0 5px 0;
    font-size: 14px;
    color: #b8b8b8;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-info .stat-value {
    font-size: 28px;
    font-weight: bold;
    color: #ffffff;
    text-shadow: 0 0 10px rgba(255,255,255,0.2);
}

.stat-card:nth-child(1) .stat-icon {
    background: linear-gradient(135deg, #667eea, #764ba2);
}

.stat-card:nth-child(2) .stat-icon {
    background: linear-gradient(135deg, #f093fb, #f5576c);
}

.stat-card:nth-child(3) .stat-icon {
    background: linear-gradient(135deg, #4facfe, #00f2fe);
}

.stat-card:nth-child(4) .stat-icon {
    background: linear-gradient(135deg, #43e97b, #38f9d7);
}

.stat-info h3 {
    margin: 0 0 5px 0;
    font-size: 28px;
    font-weight: 700;
    color: #2c3e50;
}

.stat-info p {
    margin: 0;
    color: #7f8c8d;
    font-size: 14px;
}

/* 图表区域 */
.charts-section {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-top: 30px;
}

.chart-container {
    background: white;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.chart-container h3 {
    margin: 0 0 20px 0;
    color: #2c3e50;
    font-size: 18px;
}

/* 页面头部 */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}

.page-header h2 {
    margin: 0;
    color: #2c3e50;
    font-size: 24px;
}

.header-actions {
    display: flex;
    gap: 15px;
    align-items: center;
}

/* 班级网格 */
.classes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.class-card {
    background: white;
    border-radius: 10px;
    padding: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.class-card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 15px;
}

.class-card h3 {
    font-size: 18px;
    font-weight: 600;
    color: #1a252f;
    margin: 0;
    line-height: 1.3;
}

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

.class-code {
    background: #e8f4fd;
    color: #2980b9;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 500;
}

.class-info {
    margin-bottom: 20px;
}

.class-description {
    color: #7f8c8d;
    font-size: 14px;
    margin-bottom: 10px;
}

.class-stats {
    display: flex;
    gap: 20px;
}

.class-stat {
    text-align: center;
}

.class-stat-number {
    font-size: 20px;
    font-weight: 700;
    color: #2c3e50;
}

.class-stat-label {
    font-size: 12px;
    color: #7f8c8d;
}

.class-actions {
    display: flex;
    gap: 10px;
}

/* 学生表格 */
.students-table-container {
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    overflow: hidden;
}

.students-table {
    width: 100%;
    border-collapse: collapse;
    background: rgba(30, 30, 60, 0.6);
    border-radius: 10px;
    overflow: hidden;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.1);
}

.students-table th {
    background: linear-gradient(135deg, rgba(50, 50, 100, 0.8), rgba(60, 60, 120, 0.6));
    padding: 15px;
    text-align: left;
    font-weight: 600;
    color: #ffffff;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    text-shadow: 0 0 5px rgba(255,255,255,0.2);
}

.students-table td {
    padding: 15px;
    border-bottom: 1px solid rgba(255,255,255,0.05);
    color: #e8e8e8;
    background: rgba(20, 20, 40, 0.3);
}

.students-table tr:hover {
    background: linear-gradient(90deg, rgba(100, 100, 200, 0.1), rgba(150, 100, 200, 0.05));
}

/* 考试任务列表 */
.assignments-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* 考试任务表格容器（使用表格渲染时） */
#assignmentsTable table {
    color: #e8e8e8;
    background: rgba(30, 30, 60, 0.6);
    border-radius: 10px;
    overflow: hidden;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.1);
}

#assignmentsTable thead th {
    color: #ffffff;
    font-weight: 700;
    background: linear-gradient(135deg, rgba(50, 50, 100, 0.8), rgba(60, 60, 120, 0.6));
    border-bottom: 1px solid rgba(255,255,255,0.1);
    text-shadow: 0 0 5px rgba(255,255,255,0.2);
}

#assignmentsTable tbody td {
    color: #e8e8e8;
    font-weight: 600;
    background: rgba(20, 20, 40, 0.3);
    border-bottom: 1px solid rgba(255,255,255,0.05);
}

#assignmentsTable .badge-success {
    color: #28a745;
    background: rgba(40, 167, 69, 0.2);
    border: 1px solid rgba(40, 167, 69, 0.3);
}
#assignmentsTable .badge-secondary {
    color: #b8b8b8;
    background: rgba(100, 100, 200, 0.2);
    border: 1px solid rgba(100, 100, 200, 0.3);
}

/* 列居中 */
.assignments-table-center thead th,
.assignments-table-center tbody td {
    text-align: center;
    vertical-align: middle;
}

/* 列宽优化：开始时间、时长、状态缩小，操作列加宽并单行排列按钮 */
#assignmentsTable table th:nth-child(4),
#assignmentsTable table td:nth-child(4) {
    width: 150px; /* 开始时间 */
}

#assignmentsTable table th:nth-child(5),
#assignmentsTable table td:nth-child(5) {
    width: 80px; /* 时长 */
}

#assignmentsTable table th:nth-child(6),
#assignmentsTable table td:nth-child(6) {
    width: 90px; /* 状态 */
}

#assignmentsTable table th:nth-child(7),
#assignmentsTable table td:nth-child(7) {
    width: 260px; /* 操作列加宽，三按钮同行 */
}

#assignmentsTable td:last-child {
    white-space: nowrap; /* 防止按钮换行 */
}

#assignmentsTable td:last-child .btn {
    margin-right: 8px;
}

#assignmentsTable td:last-child .btn:last-child {
    margin-right: 0;
}

.assignment-card {
    background: white;
    border-radius: 10px;
    padding: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.assignment-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 15px;
}

.assignment-name {
    font-size: 18px;
    font-weight: 600;
    color: #2c3e50;
    margin: 0;
}

.assignment-status {
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
}

.assignment-status.scheduled {
    background: #e8f4fd;
    color: #3498db;
}

.assignment-status.active {
    background: #d4edda;
    color: #155724;
}

.assignment-status.completed {
    background: #f8d7da;
    color: #721c24;
}

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

.assignment-detail {
    display: flex;
    flex-direction: column;
}

.assignment-detail-label {
    font-size: 12px;
    color: #7f8c8d;
    margin-bottom: 5px;
}

.assignment-detail-value {
    font-size: 14px;
    color: #000000; /* 使用纯黑色，最大对比度 */
    font-weight: 700; /* 加粗以便更清晰可见 */
}

.assignment-stats {
    display: flex;
    gap: 30px;
    margin-top: 15px;
}

.assignment-stat {
    text-align: center;
}

.assignment-stat-number {
    font-size: 18px;
    font-weight: 700;
    color: #2c3e50;
}

.assignment-stat-label {
    font-size: 12px;
    color: #7f8c8d;
}

/* 统计内容 */
.statistics-content {
    background: white;
    border-radius: 10px;
    padding: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

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

.stat-overview-card {
    text-align: center;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 8px;
}

.stat-overview-number {
    font-size: 32px;
    font-weight: 700;
    color: #2c3e50;
    margin-bottom: 5px;
}

.stat-overview-label {
    font-size: 14px;
    color: #7f8c8d;
}

.student-scores-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.student-scores-table th,
.student-scores-table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #dee2e6;
}

.student-scores-table th {
    background: #f8f9fa;
    font-weight: 600;
    color: #2c3e50;
}

.question-stats-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.question-stats-table th,
.question-stats-table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #dee2e6;
}

.question-stats-table th {
    background: #f8f9fa;
    font-weight: 600;
    color: #2c3e50;
}

.correct-rate {
    font-weight: 600;
}

.correct-rate.high {
    color: #28a745;
}

.correct-rate.medium {
    color: #ffc107;
}

.correct-rate.low {
    color: #dc3545;
}

/* 模态框 */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
}

.modal-content {
    background-color: white;
    margin: 5% auto;
    padding: 0;
    border-radius: 10px;
    width: 90%;
    max-width: 600px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

.modal-header {
    padding: 20px 25px;
    border-bottom: 1px solid #dee2e6;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    margin: 0;
    color: #2c3e50;
    font-size: 18px;
}

.close {
    color: #aaa;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: #000;
}

.modal-body {
    padding: 25px;
}

/* 班级详情样式 */
.class-details {
    color: #2c3e50;
    line-height: 1.6;
}

.class-details h4 {
    color: #1a252f;
    font-size: 20px;
    font-weight: 600;
    margin: 0 0 20px 0;
    padding-bottom: 10px;
    border-bottom: 2px solid #3498db;
}

.class-details p {
    color: #34495e;
    margin: 12px 0;
    font-size: 14px;
}

.class-details strong {
    color: #2c3e50;
    font-weight: 600;
    display: inline-block;
    min-width: 80px;
}

.modal-footer {
    padding: 20px 25px;
    border-top: 1px solid #dee2e6;
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

/* 表单样式 */
.form-group {
    margin-bottom: 20px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #333;
    text-shadow: 0 0 5px rgba(255,255,255,0.1);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid rgba(255,255,255,0.2);
    border-radius: 8px;
    font-size: 14px;
    background: rgba(30, 30, 60, 0.6);
    color: #ffffff;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #4a90e2;
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.2);
    background: rgba(40, 40, 80, 0.8);
}

.form-text {
    font-size: 12px;
    color: #b8b8b8;
    margin-top: 5px;
}

/* 按钮样式 */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    backdrop-filter: blur(10px);
    text-shadow: 0 0 5px rgba(255,255,255,0.2);
}

.btn-primary {
    background: linear-gradient(135deg, #4a90e2, #7b68ee);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
    box-shadow: 0 4px 15px rgba(74, 144, 226, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(74, 144, 226, 0.5);
    background: linear-gradient(135deg, #5ba0f2, #8b78fe);
}

.btn-secondary {
    background: linear-gradient(135deg, rgba(100, 100, 200, 0.3), rgba(150, 100, 200, 0.2));
    color: #333;
    border: 1px solid rgba(255,255,255,0.1);
}

.btn-secondary:hover {
    background: linear-gradient(135deg, rgba(100, 100, 200, 0.4), rgba(150, 100, 200, 0.3));
    color: #ffffff;
}

.btn-success {
    background: linear-gradient(135deg, #28a745, #20c997);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
    box-shadow: 0 4px 15px rgba(40, 167, 69, 0.3);
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(40, 167, 69, 0.5);
}

.btn-danger {
    background: linear-gradient(135deg, #dc3545, #c82333);
    color: white;
    border: 1px solid rgba(255,255,255,0.2);
    box-shadow: 0 4px 15px rgba(220, 53, 69, 0.3);
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(220, 53, 69, 0.5);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 12px;
}

/* 选择框样式 */
.form-select {
    padding: 10px 12px;
    border: 1px solid #dee2e6;
    border-radius: 6px;
    font-size: 14px;
    background-color: white;
    cursor: pointer;
}

.form-select:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* 加载状态 */
.loading {
    text-align: center;
    padding: 40px;
    color: #7f8c8d;
}

.loading i {
    font-size: 24px;
    margin-bottom: 10px;
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255,255,255,0.9);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.loading-content {
    text-align: center;
    color: #2c3e50;
}

.loading-content i {
    font-size: 32px;
    margin-bottom: 15px;
    color: #667eea;
}

/* 消息提示 */
.message {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 20px;
    border-radius: 6px;
    color: white;
    font-weight: 500;
    z-index: 3000;
    display: flex;
    align-items: center;
    gap: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.message.success {
    background: #28a745;
}

.message.error {
    background: #dc3545;
}

.message.warning {
    background: #ffc107;
    color: #212529;
}

.message button {
    background: none;
    border: none;
    color: inherit;
    font-size: 18px;
    cursor: pointer;
    padding: 0;
    margin-left: 10px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .teacher-dashboard {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
    }

    .sidebar-nav ul {
        display: flex;
        overflow-x: auto;
    }

    .nav-item {
        white-space: nowrap;
        min-width: 120px;
    }

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

    .form-row {
        grid-template-columns: 1fr;
    }

    .header-actions {
        flex-direction: column;
        gap: 10px;
    }

    .modal-content {
        width: 95%;
        margin: 10% auto;
    }
}

@media (max-width: 480px) {
    .content {
        padding: 15px;
    }

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

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

    .assignment-info {
        grid-template-columns: 1fr;
    }

    .assignment-stats {
        flex-direction: column;
        gap: 15px;
    }
}

/* 表单提示文字样式 */
.form-text {
    display: block;
    margin-top: 5px;
    font-size: 12px;
    color: #6c757d;
    line-height: 1.4;
}

/* 登录检查页面样式 */
.login-check-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.login-check-content {
    background: white;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    text-align: center;
    max-width: 400px;
    width: 90%;
}

.login-check-icon {
    font-size: 48px;
    color: #667eea;
    margin-bottom: 20px;
}

.login-check-content h2 {
    color: #333;
    margin-bottom: 15px;
    font-size: 24px;
}

.login-check-content p {
    color: #666;
    margin-bottom: 30px;
    font-size: 16px;
    line-height: 1.5;
}

.login-check-actions {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

.login-check-actions .btn {
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all 0.3s ease;
}

.login-check-actions .btn-primary {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    border: none;
}

.login-check-actions .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(102, 126, 234, 0.3);
}

.login-check-actions .btn-secondary {
    background: #f8f9fa;
    color: #6c757d;
    border: 1px solid #dee2e6;
}

.login-check-actions .btn-secondary:hover {
    background: #e9ecef;
    transform: translateY(-2px);
}

@media (max-width: 480px) {
    .login-check-content {
        padding: 30px 20px;
    }

    .login-check-actions {
        flex-direction: column;
    }

    .login-check-actions .btn {
        width: 100%;
        justify-content: center;
    }
}

/* 班级详情页面样式 */
.class-detail-view {
    padding: 20px 0;
}

.class-detail-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 2px solid #e9ecef;
}

.class-detail-header h4 {
    margin: 0;
    color: #2c3e50;
    font-size: 24px;
    font-weight: 600;
}

.class-code-badge {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 0.5px;
}

.class-detail-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.detail-section {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    border: 1px solid #e9ecef;
}

.detail-section h5 {
    margin: 0 0 20px 0;
    color: #495057;
    font-size: 18px;
    font-weight: 600;
    border-bottom: 2px solid #e9ecef;
    padding-bottom: 10px;
}

.detail-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.detail-item {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.detail-item label {
    font-weight: 600;
    color: #6c757d;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.detail-item span {
    color: #2c3e50;
    font-size: 16px;
    font-weight: 500;
}

.detail-item .class-code {
    font-family: 'Courier New', monospace;
    background: #f8f9fa;
    padding: 8px 12px;
    border-radius: 6px;
    border: 1px solid #dee2e6;
    font-weight: 600;
    color: #495057;
}

.class-description {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 8px;
    border-left: 4px solid #667eea;
    margin: 0;
    line-height: 1.6;
    color: #495057;
    font-style: italic;
}

/* CSV上传区域样式 */
.csv-upload-section {
    position: relative;
}

.csv-actions {
    display: flex;
    gap: 10px;
    margin-top: 10px;
    justify-content: flex-end;
}

.csv-actions .btn {
    font-size: 12px;
    padding: 6px 12px;
}

.btn-outline-primary {
    color: #007bff;
    border-color: #007bff;
    background-color: transparent;
}

.btn-outline-primary:hover {
    color: #fff;
    background-color: #007bff;
    border-color: #007bff;
}

.btn-outline-secondary {
    color: #6c757d;
    border-color: #6c757d;
    background-color: transparent;
}

.btn-outline-secondary:hover {
    color: #fff;
    background-color: #6c757d;
    border-color: #6c757d;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .class-detail-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 15px;
    }

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

    .detail-section {
        padding: 20px;
    }

    .csv-actions {
        flex-direction: column;
        align-items: stretch;
    }

    .csv-actions .btn {
        width: 100%;
    }
}

/* 密码相关样式 */
.password-input-group {
    display: flex;
    gap: 8px;
    align-items: center;
}

.password-input-group input {
    flex: 1;
}

.password-display-group {
    display: flex;
    align-items: center;
    gap: 8px;
}

.password-text {
    font-family: 'Courier New', monospace;
    background: #f8f9fa;
    padding: 4px 8px;
    border-radius: 4px;
    border: 1px solid #dee2e6;
    font-size: 14px;
    color: #495057;
    user-select: all;
    min-width: 80px;
}

.password-mask {
    font-family: 'Courier New', monospace;
    background: #f8f9fa;
    padding: 4px 8px;
    border-radius: 4px;
    border: 1px solid #dee2e6;
    font-size: 14px;
    color: #6c757d;
    user-select: none;
    min-width: 80px;
}

.password-display-group button {
    padding: 4px 8px;
    font-size: 12px;
    line-height: 1.2;
    border-radius: 4px;
    border: 1px solid #dee2e6;
    background: white;
    color: #6c757d;
    cursor: pointer;
    transition: all 0.2s ease;
}

.password-display-group button:hover {
    background: #f8f9fa;
    border-color: #adb5bd;
    color: #495057;
}

.password-display-group button i {
    font-size: 12px;
}

.btn-xs {
    padding: 2px 6px;
    font-size: 12px;
    line-height: 1.2;
    border-radius: 3px;
}

@media (max-width: 768px) {
    .password-input-group {
        flex-direction: column;
        align-items: stretch;
    }
}