/* ==============================================
   ADMIN PANEL STYLES
   ============================================== */

.admin-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-2xl) var(--spacing-lg);
}

.admin-header {
    background: linear-gradient(135deg, #7c3aed 0%, #a855f7 100%);
    color: white;
    padding: var(--spacing-xl);
    border-radius: 16px;
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
}

.admin-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.admin-subtitle {
    opacity: 0.9;
    font-size: 1.1rem;
}

/* Login Form */
.login-container {
    max-width: 400px;
    margin: 100px auto;
    background: var(--bg-card);
    padding: var(--spacing-2xl);
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    text-align: center;
}

.login-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
}

.login-title {
    font-size: 1.8rem;
    margin-bottom: var(--spacing-xl);
    color: var(--primary-dark);
}

.form-group {
    margin-bottom: var(--spacing-lg);
    text-align: left;
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
    color: var(--text-primary);
}

.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: var(--font-main);
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

/* Admin Sections */
.admin-nav {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.admin-nav-btn {
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--bg-hover);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.admin-nav-btn:hover {
    background: var(--border-color);
}

.admin-nav-btn.active {
    background: var(--primary-blue);
    color: white;
    border-color: var(--primary-blue);
}

.admin-section {
    display: none;
}

.admin-section.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

/* Materials List */
.materials-list {
    margin-top: var(--spacing-xl);
}

.material-item {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    transition: all var(--transition-normal);
}

.material-item:hover {
    border-color: var(--primary-blue);
    box-shadow: var(--shadow-md);
}

.material-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.material-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary-dark);
    flex: 1;
}

.material-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.material-description {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

.material-meta {
    display: flex;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
    align-items: center;
}

.material-category {
    background: var(--bg-hover);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary);
}

.material-tags {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.tag {
    background: #dbeafe;
    color: #1e40af;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.material-link {
    color: var(--primary-blue);
    text-decoration: none;
    font-size: 0.9rem;
    word-break: break-all;
}

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

/* Tag Filter */
.tag-filter {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.tag-filter-title {
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--primary-dark);
}

.tag-filter-list {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.tag-filter-item {
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-hover);
    border: 2px solid var(--border-color);
    border-radius: 20px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.tag-filter-item:hover {
    background: var(--border-color);
}

.tag-filter-item.active {
    background: var(--primary-blue);
    color: white;
    border-color: var(--primary-blue);
}

/* Action Buttons */
.btn-edit {
    background: #fbbf24;
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-edit:hover {
    background: #f59e0b;
    transform: translateY(-2px);
}

.btn-delete {
    background: #ef4444;
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-delete:hover {
    background: #dc2626;
    transform: translateY(-2px);
}

.btn-success {
    background: #10b981;
    color: white;
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-success:hover {
    background: #059669;
    transform: translateY(-2px);
}

.btn-cancel {
    background: var(--bg-hover);
    color: var(--text-primary);
    padding: var(--spacing-md) var(--spacing-xl);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-cancel:hover {
    background: var(--border-color);
}

/* Form Card */
.form-card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.form-actions {
    display: flex;
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
}

/* Checkbox Group */
.checkbox-group {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.checkbox-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-hover);
    border-radius: 8px;
}

.checkbox-item input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

/* Logout Button */
.logout-btn {
    background: #ef4444;
    color: white;
    padding: var(--spacing-sm) var(--spacing-lg);
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.logout-btn:hover {
    background: #dc2626;
    transform: translateY(-2px);
}

/* Stats Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: var(--spacing-lg);
    text-align: center;
}

.stat-card-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-blue);
    margin-bottom: var(--spacing-sm);
}

.stat-card-label {
    color: var(--text-secondary);
    font-weight: 600;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: var(--spacing-2xl);
    color: var(--text-secondary);
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
    opacity: 0.5;
}

.empty-state-text {
    font-size: 1.2rem;
}

/* Upload Success Animation */
@keyframes uploadSuccess {
    0% {
        transform: scale(1);
        border-color: var(--border-color);
    }
    50% {
        transform: scale(1.02);
        border-color: #10b981;
        box-shadow: 0 0 20px rgba(16, 185, 129, 0.3);
    }
    100% {
        transform: scale(1);
        border-color: var(--border-color);
    }
}

.upload-success {
    animation: uploadSuccess 0.6s ease;
}

/* Upload Progress Indicator */
.upload-progress {
    position: relative;
    overflow: hidden;
}

.upload-progress::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, #10b981, #34d399);
    animation: uploadProgressBar 1s ease-in-out;
}

@keyframes uploadProgressBar {
    0% { left: -100%; }
    100% { left: 100%; }
}

/* Success Flash */
.success-flash {
    position: fixed;
    top: 20px;
    right: 20px;
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: white;
    padding: 15px 25px;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(16, 185, 129, 0.4);
    z-index: 9999;
    animation: successSlideIn 0.5s ease, successFadeOut 0.5s ease 2.5s forwards;
    font-weight: 600;
}

@keyframes successSlideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes successFadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
        transform: translateY(-20px);
    }
}

/* Clear Filters Button */
.clear-filters-btn {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.clear-filters-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

/* Responsive */
@media (max-width: 768px) {
    .admin-container {
        padding: var(--spacing-lg) var(--spacing-md);
    }
    
    .material-header {
        flex-direction: column;
    }
    
    .material-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .form-actions button {
        width: 100%;
    }
    
    .success-flash {
        left: 50%;
        transform: translateX(-50%);
        right: auto;
        top: 10px;
        max-width: 90%;
    }
}