Custom Colour

[ItzCodyyTM]

Hi There!

I would like to change the colour of the button, navbar, etc with a custom HEX code but I cannot find where to do so. I've changed the values of the "red" theme to my custom HEX but it has not changed. What should I do to change that?

Also I would like to change the background colour of the card, is there a way I can do that?

Thanks