woocommerce/plugins/woocommerce-blocks/assets/js/base/components/dropdown-selector/style.scss

.wc-block-dropdown-selector {
	max-width: 300px;
	position: relative;
	width: 100%;
}

.wc-block-dropdown-selector__input-wrapper {
	align-items: baseline;
	border: 1px solid #9f9f9f;
	border-radius: 4px;
	cursor: text;
	display: flex;
	flex-wrap: wrap;
	padding: 2px;

	.is-disabled & {
		background-color: $core-grey-light-500;
	}
}

.wc-block-dropdown-selector__placeholder {
	font-size: 0.8em;
	height: 1.8em;
	margin: 0 $gap-smallest;
	white-space: nowrap;
}

.wc-block-dropdown-selector__input {
	background: transparent;
	border: 0;
	flex: 1;
	font-size: 0.8em;
	height: 1.8em;
	min-width: 0;
	margin: 1.5px;

	&:hover,
	&:focus,
	&:active {
		outline: 0;
	}
}

.wc-block-dropdown-selector__selected-chip {
	background-color: $core-grey-light-600;
	border: 1px solid #9f9f9f;
	border-radius: 4px;
	color: $core-grey-dark-600;
	display: inline-block;
	font-size: 0.8em;
	font-weight: inherit;
	height: 1.8em;
	margin: 1.5px;
	padding: 0 0 0 0.3em;
	white-space: nowrap;

	&:hover,
	&:focus,
	&:active {
		background-color: $core-grey-light-600;
		border: 1px solid #9f9f9f;
		color: $core-grey-dark-600;
	}
}

.wc-block-dropdown-selector__selected-chip__remove {
	background-color: transparent;
	border: 0;
	display: inline-block;
	padding: 0 0.3em;
}

.wc-block-dropdown-selector__list {
	list-style: none;
	margin: -1px 0 0;
	position: absolute;
	left: 0;
	right: 0;
	top: 100%;
	max-height: 300px;
	overflow-y: auto;
	z-index: 1;

	&:not(:empty) {
		border: 1px solid #9f9f9f;
	}
}

.wc-block-dropdown-selector__list-item {
	background-color: #fff;
	color: $core-grey-dark-600;
	padding: 0 $gap-smallest;

	&.is-selected {
		background-color: $core-grey-light-600;
	}

	&:hover,
	&:focus,
	&.is-highlighted,
	&:active {
		background-color: #00669e;
		color: #fff;
	}
}