How to make a gradiant cover the whole page?

I have a gradiant in a css file and have linked to it on one of my pages and it works fine but it only covers around anything i put into the html and doesn't cover the whole page. Its almost like i need a empty element that covers the whole page so that the gradiant can fill it in

here is the css rule ....
.gradiant{
width: 100%;
height: 100%;
background: #1e5799; /* Old browsers */
background: #1e5799; /* Old browsers */
background: -moz-linear-gradient(top, #1e5799 0%, #7db9e8 48%, #7db9e8 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#1e5799), color-stop(48%,#7db9e8), color-stop(100%,#7db9e8)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #1e5799 0%,#7db9e8 48%,#7db9e8 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #1e5799 0%,#7db9e8 48%,#7db9e8 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #1e5799 0%,#7db9e8 48%,#7db9e8 100%); /* IE10+ */
background: linear-gradient(to bottom, #1e5799 0%,#7db9e8 48%,#7db9e8 100%); /* W3C */
filter: progidXImageTransform.Microsoft.gradient( startColorstr='#1e5799', endColorstr='#7db9e8',GradientType=0 );} /* IE6-9 */

 

You don't write what you are applying this CSS to.

Try this:

html { min-height:100%; }
body { min-height:100%; }

Now add your gradient CSS to your body element as well.