WebBrowser component not showing CSS 3

I am building a piece of software that requires a WebBrowser component.
Unfortunatly it wont show my page right.

my content uses this CSS style:

.content_mid{
 background-image:url(http://img.awesome-o.net/Content_Mid.png);
 background-size: 100% 100%;
 vertical-align:text-top;
 padding-left: 40px;
 padding-right:20px;
 min-height:400px; 
 }
 

Since i already found out the WebBrowser component uses the installed version of interwebs explorer i checked the html on internet explorer, and it shows perfectly.

Here you see what it shows on IE:http://i.stack.imgur.com/rMrue.jpg

And here is how it displays on the webbrowser component:http://i.stack.imgur.com/gADsG.jpg

So.. i checked the browser version:

Debug.WriteLine("WebBrowser version: " + webBrowser1.Version);
 output: WebBrowser version: 9.0.8112.16443
 

So that should be alright i guess,

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