:root {
    --sidebar-width: 300px;
    --primary-color: #d4a932; /* Gold */
    --accent-color: #fdc60a;
    --text-color: rgba(255, 255, 255, 0.9);
    --text-light: rgba(255, 255, 255, 0.6);
    --border-color: rgba(212, 169, 50, 0.2);
    --bg-hover: rgba(212, 169, 50, 0.1);
}

/* Category Tree Styles */
.category-tree {
    list-style: none;
    padding: 0;
    margin: 0;
}

.category-tree-item {
    margin-bottom: 0.5rem;
}

.category-tree-header {
    display: flex;
    align-items: center;
    padding: 0.6rem 0.75rem;
    cursor: pointer;
    border-radius: 6px;
    transition: all 0.2s;
    gap: 0;
}

.category-tree-header:hover {
    background-color: var(--bg-hover);
}

.category-tree-header.active {
    color: var(--primary-color);
}

.category-tree-toggle {
    background: rgba(212, 169, 50, 0.1);
    border: 1px solid rgba(212, 169, 50, 0.3);
    border-radius: 4px;
    padding: 0;
    margin-left: auto;
    cursor: pointer;
    color: var(--primary-color);
    transition: all 0.2s;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.category-tree-toggle:hover {
    background: rgba(212, 169, 50, 0.2);
    border-color: var(--primary-color);
}

.category-tree-toggle.expanded {
    background: rgba(212, 169, 50, 0.2);
}

.category-tree-toggle.hidden {
    visibility: hidden;
}

.category-checkbox {
    margin-right: 0.7rem;
    width: 17px;
    height: 17px;
    border: 2px solid rgba(212, 169, 50, 0.4);
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    flex-shrink: 0;
}

.category-tree-header.active .category-checkbox {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}

.category-tree-header:hover .category-checkbox {
    border-color: var(--primary-color);
}

.category-checkbox::after {
    content: '\f00c';
    font-family: 'Font Awesome 5 Free';
    font-weight: 900;
    font-size: 10px;
    color: #070d15; /* Dark text for checkmark on gold bg */
    display: none;
}

.category-tree-header.active .category-checkbox::after {
    display: block;
}

.category-name {
    flex-grow: 1;
    font-size: 0.9rem;
    font-family: 'Montserrat', sans-serif;
    color: var(--text-color);
    transition: color 0.3s;
}

.category-tree-header.active .category-name {
    color: var(--primary-color);
    font-weight: 500;
}

.category-count {
    font-size: 0.75rem;
    font-family: 'Montserrat', sans-serif;
    color: var(--text-light);
    background: rgba(255, 255, 255, 0.1);
    padding: 0.15rem 0.5rem;
    border-radius: 10px;
    margin-left: 0.5rem;
}

.category-children {
    padding: 0.75rem;
    margin-left: 0;
    margin-top: 0.5rem;
    margin-bottom: 0.5rem;
    display: none;
    background: rgba(7, 13, 21, 0.4);
    border: 1px solid rgba(212, 169, 50, 0.15);
    border-radius: 8px;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.2);
}

.category-children.expanded {
    display: block;
}

/* Sidebar Specific Overrides */
.sidebar-filter-card .category-tree {
    margin-top: 0.5rem;
    max-height: 400px;
    overflow-y: auto;
}

.sidebar-filter-card .category-tree::-webkit-scrollbar {
    width: 6px;
}

.sidebar-filter-card .category-tree::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 3px;
}

.sidebar-filter-card .category-tree::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 3px;
}

.sidebar-filter-card .category-tree::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
}

/* Subitem (Grandchildren) Styles */
.category-tree-subitem {
    margin-bottom: 0.4rem;
}

.category-tree-subitem:last-child {
    margin-bottom: 0;
}

.category-tree-subitem .category-tree-header {
    padding: 0.5rem 0.6rem;
    font-size: 0.85rem;
    border-radius: 6px;
    margin-left: 0;
    background: rgba(255, 255, 255, 0.02);
}

.category-tree-subitem .category-tree-header:hover {
    background-color: rgba(212, 169, 50, 0.15);
    border: 1px solid rgba(212, 169, 50, 0.2);
    margin: -1px;
}

.category-tree-subitem .category-tree-header.active {
    background-color: rgba(212, 169, 50, 0.2);
    border: 1px solid rgba(212, 169, 50, 0.3);
    margin: -1px;
}

.category-tree-subitem .category-checkbox {
    width: 15px;
    height: 15px;
    margin-right: 0.6rem;
    border-width: 1.5px;
}

.category-tree-subitem .category-name {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.85);
}

.category-tree-subitem .category-tree-header.active .category-name {
    color: var(--primary-color);
    font-weight: 500;
}

/* Parent Badge */
.category-parent-badge {
    font-size: 0.65rem;
    color: rgba(212, 169, 50, 0.9);
    background: rgba(212, 169, 50, 0.12);
    padding: 0.2rem 0.6rem;
    border-radius: 12px;
    margin-left: auto;
    white-space: nowrap;
    border: 1px solid rgba(212, 169, 50, 0.2);
    font-weight: 500;
    letter-spacing: 0.02em;
}

/* Horizontal Tags Loading State */
.category-tags.loading {
    opacity: 0.5;
    pointer-events: none;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .sidebar-filter {
        width: 100%;
        max-width: none;
    }

    .category-tree-header {
        padding: 0.6rem 0.5rem;
    }

    .category-name {
        font-size: 0.95rem;
    }

    .category-parent-badge {
        font-size: 0.65rem;
        padding: 0.1rem 0.4rem;
    }
}