Thread: Post block image

Post block image

I'm tying to add a custom background post block image on the front page of my site looks great but does not work with mobile versions I'm using the following CSS.

.post-block {
background: url("http://www.testsite.com/wp-content/uploads/2014/12/A-Custom-Background-Image.png") repeat-x scroll center top #fff;
border: 1px solid #fff;
border-radius: 3px;
margin: 0;
padding: 13px;
width: 560px;
}

is there a way to do this so it works responsive in all platforms including mobile. I notice in other sites the url is short like the following url("images/block_buyyt_featured.png") repeat-x scroll center top #fff
appreciate any help thanks.