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.