woocommerce/plugins/woocommerce-admin/client/layout/sidebar/style.scss

/** @format */

.woocommerce-layout__sidebar-header {
	display: flex;
	flex-direction: row;
	align-items: center;

	.woocommerce-layout__sidebar-header-label {
		flex-grow: 0;
		text-transform: uppercase;
		margin-right: 8px;
		color: $gray-text;
		font-weight: 500;
		font-size: 1.1em;
	}

	.woocommerce-layout__sidebar-header-divider {
		flex-grow: 1;
		height: 1px;
		background-color: $gray-darken-40;
	}
}