/* Admin Dashboard Specific Styles */

.admin-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2rem 0;
    margin-bottom: 2rem;
}

.admin-header h1 {
    color: white;
    margin: 0;
}

.admin-header .user-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.9375rem;
}

.admin-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
    border-bottom: 2px solid var(--border-color);
    overflow-x: auto;
}

.admin-tab {
    padding: 0.75rem 1.5rem;
    background: none;
    border: none;
    border-bottom: 3px solid transparent;
    color: var(--text-secondary);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    white-space: nowrap;
}

.admin-tab:hover {
    color: var(--primary-color);
}

.admin-tab.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.admin-panel {
    display: none;
}

.admin-panel.active {
    display: block;
}

.admin-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: var(--card-bg);
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    text-align: center;
}

.stat-card .stat-value {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.stat-card .stat-label {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.student-list,
.lesson-list,
.assignment-list,
.submission-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

.list-item {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    margin-bottom: 0.75rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: box-shadow 0.2s;
}

.list-item:hover {
    box-shadow: var(--shadow-md);
}

.list-item-content {
    flex: 1;
}

.list-item-title {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.list-item-meta {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.list-item-actions {
    display: flex;
    gap: 0.5rem;
}

.submission-grouping {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.submission-grouping-header {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
}

.submission-view-toggle {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.submission-group-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: flex-end;
}

.submission-group-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.submission-group,
.subject-group {
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--card-bg);
}

.submission-group > summary,
.subject-group > summary {
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    cursor: pointer;
}

.submission-group summary::-webkit-details-marker,
.subject-group summary::-webkit-details-marker {
    display: none;
}

.submission-group-content {
    padding: 0 1rem 1rem;
}

.subject-group {
    margin-top: 0.5rem;
    background: var(--bg-color);
}

.subject-group > summary {
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius-sm);
}

.group-title {
    font-weight: 600;
    color: var(--text-primary);
}

.group-count {
    font-size: 0.8125rem;
    color: var(--text-secondary);
    background: var(--bg-color);
    border-radius: 999px;
    padding: 0.125rem 0.5rem;
    white-space: nowrap;
}

.submission-items .list-item {
    margin: 0.5rem 0 0;
}

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    padding: 3rem 2rem;
    text-align: center;
    background-color: var(--bg-color);
    transition: all 0.2s;
    cursor: pointer;
}

.upload-area:hover,
.upload-area.drag-over {
    border-color: var(--primary-color);
    background-color: rgba(37, 99, 235, 0.05);
}

.upload-area input[type="file"] {
    display: none;
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.upload-text {
    font-size: 1.125rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.upload-hint {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.progress-bar-container {
    width: 100%;
    height: 8px;
    background-color: var(--border-color);
    border-radius: 9999px;
    overflow: hidden;
    margin-top: 1rem;
}

.progress-bar {
    height: 100%;
    background-color: var(--primary-color);
    transition: width 0.3s;
    border-radius: 9999px;
}

.student-progress {
    margin-top: 1rem;
}

.progress-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem;
    background: var(--bg-color);
    border-radius: var(--radius-sm);
    margin-bottom: 0.5rem;
}

.schedule-form {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.schedule-form .form-group {
    margin-bottom: 0;
}

.progress-lesson {
    flex: 1;
    font-weight: 500;
}

.progress-status {
    margin-right: 1rem;
}

.assignment-form {
    display: grid;
    gap: 1rem;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

.empty-state {
    text-align: center;
    padding: 3rem 2rem;
    color: var(--text-secondary);
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.3;
}

.empty-state-text {
    font-size: 1.125rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.empty-state-hint {
    font-size: 0.9375rem;
    color: var(--text-secondary);
}

.resource-form {
    display: grid;
    gap: 1rem;
}

.resource-divider {
    text-align: center;
    margin: 1.5rem 0;
    color: var(--text-secondary);
    font-weight: 600;
}

.resource-status {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

@media (max-width: 768px) {
    .admin-stats {
        grid-template-columns: 1fr;
    }

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

    .list-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .list-item-actions {
        width: 100%;
        justify-content: flex-end;
    }
}