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

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

.container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: white;
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

header h1 {
    color: #4a5568;
    font-size: 28px;
    font-weight: 600;
}

header h1 i {
    color: #667eea;
    margin-right: 10px;
}

.header-controls {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

.btn-success {
    background: linear-gradient(135deg, #48bb78 0%, #38a169 100%);
    color: white;
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(72, 187, 120, 0.4);
}

.btn-warning {
    background: linear-gradient(135deg, #ed8936 0%, #dd6b20 100%);
    color: white;
}

.btn-warning:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(237, 137, 54, 0.4);
}

.btn-info {
    background: linear-gradient(135deg, #4299e1 0%, #3182ce 100%);
    color: white;
}

.btn-info:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(66, 153, 225, 0.4);
}

.btn-secondary {
    background: #e2e8f0;
    color: #4a5568;
}

.btn-secondary:hover {
    background: #cbd5e0;
}

.btn-danger {
    background: linear-gradient(135deg, #f56565 0%, #e53e3e 100%);
    color: white;
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(245, 101, 101, 0.4);
}

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

/* 批量操作工具栏 */
.batch-toolbar {
    background: white;
    padding: 15px 20px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.batch-info {
    font-weight: 500;
    color: #4a5568;
}

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

.batch-info-display {
    background: #f7fafc;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    border-left: 4px solid #667eea;
}

.batch-info-display p {
    margin: 0;
    color: #4a5568;
}

.batch-info-display strong {
    color: #667eea;
}

.table-container {
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    overflow: hidden;
}

.table-header {
    padding: 20px;
    border-bottom: 1px solid #e2e8f0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.search-controls {
    display: flex;
    gap: 15px;
    align-items: center;
    flex-wrap: wrap;
    flex: 1;
}

.search-box {
    position: relative;
    min-width: 200px;
}

.search-box i {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #a0aec0;
}

.search-box input {
    width: 100%;
    padding: 12px 15px 12px 45px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 14px;
    transition: border-color 0.3s ease;
}

.search-box input:focus {
    outline: none;
    border-color: #667eea;
}

.filter-box {
    min-width: 150px;
}

.filter-box select {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 14px;
    background-color: white;
    transition: border-color 0.3s ease;
    cursor: pointer;
}

.filter-box select:focus {
    outline: none;
    border-color: #667eea;
}

.table-info {
    color: #718096;
    font-size: 14px;
    white-space: nowrap;
}

.table-wrapper {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

thead {
    background: linear-gradient(135deg, #f7fafc 0%, #edf2f7 100%);
}

th {
    padding: 15px 12px;
    text-align: left;
    font-weight: 600;
    color: #4a5568;
    border-bottom: 2px solid #e2e8f0;
    white-space: nowrap;
}

th i {
    margin-left: 5px;
    font-size: 12px;
    color: #a0aec0;
}

td {
    padding: 12px;
    border-bottom: 1px solid #f1f5f9;
    vertical-align: middle;
}

tbody tr:hover {
    background: #f8fafc;
    transition: background 0.2s ease;
}

/* 选择框样式 */
.row-checkbox {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: #667eea;
}

.professor-select {
    position: relative;
    cursor: pointer;
}

.professor-display {
    padding: 8px 12px;
    background: #f7fafc;
    border: 1px solid #e2e8f0;
    border-radius: 6px;
    font-size: 13px;
    color: #4a5568;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.professor-display:hover {
    background: #edf2f7;
    border-color: #cbd5e0;
}

.professor-display i {
    font-size: 12px;
    color: #a0aec0;
}

.selected-professors {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    margin-top: 4px;
}

.professor-tag {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 11px;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.professor-tag .remove {
    cursor: pointer;
    font-size: 10px;
    opacity: 0.8;
}

.professor-tag .remove:hover {
    opacity: 1;
}

.action-buttons {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

/* 教授管理样式 */
.professor-manager-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 20px;
}

.professor-list-section,
.professor-add-section {
    background: #f7fafc;
    padding: 20px;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
}

.professor-list-section h4,
.professor-add-section h4 {
    margin-bottom: 15px;
    color: #4a5568;
    font-size: 16px;
    font-weight: 600;
}

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

.professor-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px;
    background: white;
    border-radius: 8px;
    margin-bottom: 8px;
    border: 1px solid #e2e8f0;
    transition: all 0.3s ease;
}

.professor-item:hover {
    border-color: #667eea;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.1);
}

.professor-info {
    flex: 1;
}

.professor-name {
    font-weight: 600;
    color: #4a5568;
    margin-bottom: 4px;
}

.professor-details {
    font-size: 12px;
    color: #718096;
}

.professor-actions {
    display: flex;
    gap: 8px;
}

.add-professor-form {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.add-professor-form .form-group {
    margin-bottom: 0;
}

/* 统计报告样式 */
.statistics-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    border-bottom: 2px solid #e2e8f0;
    padding-bottom: 10px;
}

.tab-btn {
    padding: 10px 20px;
    border: none;
    background: none;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: #718096;
    border-radius: 8px 8px 0 0;
    transition: all 0.3s ease;
}

.tab-btn:hover {
    background: #f7fafc;
    color: #4a5568;
}

.tab-btn.active {
    background: #667eea;
    color: white;
}

.stats-content {
    display: none;
}

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

.stats-content h4 {
    margin-bottom: 15px;
    color: #4a5568;
    font-size: 18px;
}

.stats-table-container {
    overflow-x: auto;
    margin-bottom: 20px;
}

.stats-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.stats-table th {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 15px 12px;
    text-align: left;
    font-weight: 600;
}

.stats-table td {
    padding: 12px;
    border-bottom: 1px solid #f1f5f9;
}

.stats-table tbody tr:hover {
    background: #f8fafc;
}

.stats-table tbody tr:last-child {
    font-weight: 600;
    background: #f7fafc;
}

/* 模态框样式 */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background-color: white;
    margin: 10% auto;
    padding: 0;
    border-radius: 15px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    animation: modalSlideIn 0.3s ease;
}

.modal-large {
    max-width: 1000px;
}

.modal-medium {
    max-width: 600px;
}

.modal-small {
    max-width: 400px;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    padding: 20px;
    border-bottom: 1px solid #e2e8f0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    color: #4a5568;
    font-size: 18px;
    font-weight: 600;
}

.close {
    color: #a0aec0;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s ease;
}

.close:hover {
    color: #4a5568;
}

.modal-body {
    padding: 20px;
}

.professor-options {
    margin-bottom: 20px;
}

.checkbox-container {
    display: block;
    position: relative;
    padding: 12px 0;
    cursor: pointer;
    font-size: 16px;
    color: #4a5568;
    transition: all 0.3s ease;
}

.checkbox-container:hover {
    color: #667eea;
}

.checkbox-container input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.checkmark {
    height: 20px;
    width: 20px;
    background-color: #f7fafc;
    border: 2px solid #e2e8f0;
    border-radius: 4px;
    display: inline-block;
    margin-right: 12px;
    position: relative;
    transition: all 0.3s ease;
}

.checkbox-container:hover .checkmark {
    border-color: #667eea;
    background-color: #edf2f7;
}

.checkbox-container input:checked ~ .checkmark {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-color: #667eea;
}

.checkmark:after {
    content: "";
    position: absolute;
    display: none;
    left: 6px;
    top: 2px;
    width: 6px;
    height: 10px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.checkbox-container input:checked ~ .checkmark:after {
    display: block;
}

.modal-actions {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
}

/* 表单样式 */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 20px;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 8px;
    font-weight: 500;
    color: #4a5568;
    font-size: 14px;
}

.form-group input,
.form-group select {
    padding: 12px;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 14px;
    transition: border-color 0.3s ease;
    background-color: white;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: #667eea;
}

.form-group input[readonly] {
    background-color: #f7fafc;
    color: #718096;
    cursor: not-allowed;
}

.form-group input[type="number"] {
    -moz-appearance: textfield;
}

.form-group input[type="number"]::-webkit-outer-spin-button,
.form-group input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.form-help {
    font-size: 12px;
    color: #a0aec0;
    margin-top: 4px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    header {
        flex-direction: column;
        text-align: center;
    }
    
    .header-controls {
        justify-content: center;
    }
    
    .batch-toolbar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .batch-actions {
        justify-content: center;
    }
    
    .table-header {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-box,
    .filter-box {
        min-width: auto;
    }
    
    .professor-manager-content {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    th, td {
        padding: 8px 6px;
        font-size: 12px;
    }
    
    .modal-content {
        margin: 5% auto;
        width: 95%;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
    }
    
    .action-buttons {
        flex-direction: column;
    }
    
    .statistics-tabs {
        flex-direction: column;
    }
    
    .tab-btn {
        border-radius: 8px;
    }
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #a0aec0;
}

.empty-state i {
    font-size: 48px;
    margin-bottom: 20px;
    opacity: 0.5;
}

.empty-state h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: #718096;
}

.empty-state p {
    font-size: 14px;
    line-height: 1.5;
}