How to remove grey line in the header of Twenty Eleven

in style.css:

#branding {
	border-top: 2px solid #bbb;
	padding-bottom: 10px;
	position: relative;
	z-index: 2;
}

this is the style that does the grey line –
change this line:

border-top: 2px solid #bbb;

to:

border-top: none;

i.e. add:

#branding {
	border-top: none;
}

to style.css of the child theme of twenty eleven.

basic knowledge of css is essential to modifying themes – find some online tutorials, such as http://www.w3schools.com/css/

I tried adding

#branding {
	border-top: none;
}

to style.css in my twentyeleven-child folder and it makes no difference. How might I trouble-shoot this?

Thanks,
Matt

This worked great for removing the top boarder, however, I tried removing the left boarder with the following code and it didn’t work.

http://www.khartist.com

#branding {
border-top: none;
border-left: none;
}