With CSS, how do I make an image span the full width of the page as a background image?

Question

Say, like in this example here: http://www.electrictoolbox.com/examples/wide-background-image.html

When I do it, I end up getting white borders around the image no matter what I do. What am I doing wrong?

Answer 1

If you're hoping to use background-image: url(...);, I don't think you can. However, if you want to play with layering, you can do something like this:

<img class="bg" src="..." />

And then some CSS:

.bg
{
  width: 100%;
  z-index: 0;
}

You can now layer content above the stretched image by playing with z-indexes and such. One quick note, the image can't be contained in any other elements for the width: 100%; to apply to the whole page.

Here's a quick demo if you can't rely on background-size: http://jsfiddle.net/bB3Uc/

Answer 2

Background images, ideally, are always done with CSS. All other images are done with html. This will span the whole background of your site.

body {
  background: url('../images/cat.ong');
  background-size: cover;
  background-position: center;
  background-attachment: fixed;
}