Integrated message bar add style

Hi all,

I want to change the message bar his style depending of its type (error or warning).
Now I tried :

function afterRender(data) {
if (data != null) {
dps1.message(data.message, 5000, "#dc143c" ,"#fff" );
}
}

But it still shows the style that is found in the CSS. Even if I clear the CSS-class, the message doesn't get the style from the JS (there is no style at all)

Can someone help me with this issue?

Thanks in advance