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

.tree-navigation {
    max-height: 600px;
    overflow-y: auto;
}

.tree-item {
    border-bottom: 1px solid #e9ecef;
}

.tree-item:last-child {
    border-bottom: none;
}

.tree-link {
    display: block;
    padding: 0.75rem 1rem;
    color: #495057;
    text-decoration: none;
    transition: all 0.2s;
}

.tree-link:hover {
    background-color: #f8f9fa;
    color: var(--primary-color);
}

.tree-link.active {
    background-color: var(--primary-color);
    color: white;
}

.tree-children {
    background-color: #f8f9fa;
}

.tree-children .tree-link {
    padding-left: 2rem;
    font-size: 0.9rem;
}

.tree-children .tree-children .tree-link {
    padding-left: 3rem;
    font-size: 0.85rem;
}

.tree-children .tree-children .tree-children .tree-link {
    padding-left: 4rem;
    font-size: 0.85rem;
}

.article-card {
    position: relative;
    display: flex;
    flex-direction: column;
    background: #fff;
    border: 1px solid var(--border-light);
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.article-card:hover,
.article-card:focus-within {
    transform: translateY(-4px);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-lg) !important;
}

.article-card:focus-within {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

.article-image {
    height: 200px;
    overflow: hidden;
}

.article-image img {
    transition: transform 0.4s ease;
}

.article-card:hover .article-image img {
    transform: scale(1.05);
}

.article-card-title {
    color: var(--text-primary);
    transition: color 0.2s ease;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-card:hover .article-card-title,
.article-card:focus-within .article-card-title {
    color: var(--primary-color);
}

.article-card-excerpt {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.5;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.375rem;
    margin-bottom: 1rem;
}

.article-tag {
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-size: 0.7rem;
    font-weight: 500;
    color: var(--text-secondary);
    background: var(--bg-secondary);
    border-radius: 999px;
    padding: 0.2rem 0.6rem;
}

.article-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-light);
    font-size: 0.8rem;
}

.article-card-date {
    color: var(--text-muted);
    white-space: nowrap;
}

.article-card-readmore {
    display: inline-flex;
    align-items: center;
    font-weight: 600;
    color: var(--primary-color);
    white-space: nowrap;
}

.article-card-readmore i {
    transition: transform 0.2s ease;
}

.article-card:hover .article-card-readmore i,
.article-card:focus-within .article-card-readmore i {
    transform: translateX(3px);
}

@media (prefers-reduced-motion: reduce) {
    .article-card,
    .article-image img,
    .article-card-title,
    .article-card-readmore i {
        transition: none;
    }

    .article-card:hover,
    .article-card:focus-within {
        transform: none;
    }

    .article-card:hover .article-image img {
        transform: none;
    }
}

.category-card {
    max-height: 700px;
    display: flex;
    flex-direction: column;
}

.category-card .card-body {
    overflow-y: auto;
}

.tree-navigation::-webkit-scrollbar,
.category-card .card-body::-webkit-scrollbar {
    width: 6px;
}

.tree-navigation::-webkit-scrollbar-track,
.category-card .card-body::-webkit-scrollbar-track {
    background: #f1f1f1;
}

.tree-navigation::-webkit-scrollbar-thumb,
.category-card .card-body::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 3px;
}

.tree-navigation::-webkit-scrollbar-thumb:hover,
.category-card .card-body::-webkit-scrollbar-thumb:hover {
    background: #555;
}

.page-type-badge {
    font-size: 0.7rem;
    padding: 0.2rem 0.4rem;
    margin-left: 0.25rem;
}