zotero/scss/elements/_librariesCollectionsBox.scss

libraries-collections-box {
	display: flex;
	flex-direction: column;

	&[hidden] {
		display: none;
	}
	
	.body {
		display: flex;
		flex-direction: column;
		margin-inline-start: 12px;
		
		.row {
			display: flex;
			align-items: flex-start;
			gap: 4px;
			margin-inline-start: calc(16px * var(--level, 0));
			
			@include comfortable {
				padding-block: 2px;
			}
			
			&.context {
				color: var(--fill-secondary);

				.box .icon {
					opacity: 0.5;
				}
			}
			
			.box {
				@include clicky-item;
				flex: 1;
				
				&.current {
					font-weight: 600;
				}
				
				.icon {
					width: 16px;
					height: 16px;
				}
			}

			toolbarbutton {
				margin-inline-start: auto;
				visibility: hidden;
				border-radius: 2px;
			}

			&:is(:hover, :focus-within) toolbarbutton {
				visibility: visible;
			}
		}
	}

	&:not([mode=edit]) {
		.add {
			display: none;
		}
	}
}