Support for WP's built-in color themes for select2 elements

assets/css/admin.scss

@@ -6699,6 +6699,56 @@ table.bar_chart {
 	}
 }
 
+/**
+  * Select2 colors for built-in admin color themes.
+  */
+.admin-color {
+	$wp_admin_colors: (
+		blue: #096484,
+		coffee: #c7a589,
+		ectoplasm: #a3b745,
+		midnight: #e14d43,
+		ocean: #9ebaa0,
+		sunrise: #dd823b,
+		light: #04a4cc
+	);
+
+	@each $name, $color in $wp_admin_colors {
+
+		&-#{$name} {
+
+			.select2-dropdown {
+				border-color: $color;
+			}
+
+			.select2-dropdown--below {
+				box-shadow: 0 0 0 1px $color, 0 2px 1px rgba(0, 0, 0, 0.1);
+			}
+
+			.select2-dropdown--above {
+				box-shadow: 0 0 0 1px $color, 0 -2px 1px rgba(0, 0, 0, 0.1);
+			}
+
+			.select2-selection--single .select2-selection__rendered:hover {
+				color: $color;
+			}
+
+			.select2-container.select2-container--focus .select2-selection--single,
+			.select2-container.select2-container--open .select2-selection--single,
+			.select2-container.select2-container--open .select2-selection--multiple {
+				border-color: $color;
+				box-shadow: 0 0 0 1px $color;
+			}
+
+			.select2-container--default .select2-results__option--highlighted[aria-selected],
+			.select2-container--default .select2-results__option--highlighted[data-selected] {
+				background-color: $color;
+			}
+		}
+	}
+}
+
+
 .post-type-product .tablenav,
 .post-type-shop_order .tablenav {