First commit.

Signed-off-by: Chen Xiao <abigwc@gmail.com>

client/node_modules/khroma/src/methods/rgba.ts

@@ -0,0 +1,36 @@
+
+/* IMPORT */
+
+import _ from '~/utils';
+import ChannelsReusable from '~/channels/reusable';
+import Color from '~/color';
+import change from '~/methods/change';
+import type {Channels} from '~/types';
+
+/* TYPES */
+
+type IRgba = {
+  ( color: string | Channels, opacity: number ): string,
+  ( r: number, g: number, b: number, a?: number ): string
+};
+
+/* MAIN */
+
+const rgba: IRgba = ( r: string | Channels | number, g: number, b: number = 0, a: number = 1 ): string => { //TSC: `b` shouldn't have a default value
+
+  if ( typeof r !== 'number' ) return change ( r, { a: g } );
+
+  const channels = ChannelsReusable.set ({
+    r: _.channel.clamp.r ( r ),
+    g: _.channel.clamp.g ( g ),
+    b: _.channel.clamp.b ( b ),
+    a: _.channel.clamp.a ( a )
+  });
+
+  return Color.stringify ( channels );
+
+};
+
+/* EXPORT */
+
+export default rgba;