trying to resize Select Language at Sign Up

I want to resize select language at signup box but what I tried is not working.

To the style.css in my blogs-mu-child theme folder I add this

#element.style {

font-size:12px !important;

text-align:left;

width:65% !important;

}

But I see no change. However that piece of code worked in firebug.

Image attached.