You're seeing just the function new_rgba, go back to CSSEx.RGBA module for more information.

Accepts any value in the form of a binary "hsla(0, 10%, 20%, 0.5)" or "hsl(0, 10%, 20%)", any hexadecimal representation in binary in the form of "#xxx", "#xxxx", "#xxxxxx" or "#xxxxxxxx", rgb/a as "rgba(100,100,100,0.1)" or "rgb(10,20,30)", or any literal color name defined as web colors (CSSEx.Colors) - returns a %CSSEx.HSLA{} struct.