NodeBB/public/scss/modules/icon-picker.scss

.icon-container {
	.fa-nbb-none {
		border: 1px dotted $black;
	}
	.nbb-fa-icons {
		margin: 0;
		i {
			width: 36px;
			height: 36px;
			cursor: pointer;
			line-height: 36px;
			text-align: center;
			color: $body-color;
			margin: 4px;

			&:hover, &.selected {
				background: $component-active-bg;
			}
		}
	}
}