CSS3 gradient background set on body doesn't stretch but instead repeats?

Apply the following CSS:

html {
    height: 100%;
}
body {
    height: 100%;
    margin: 0;
    background-repeat: no-repeat;
    background-attachment: fixed;
}

Edit: Added margin: 0; to body declaration per comments (Martin).

Edit: Added background-attachment: fixed; to body declaration per comments (Johe Green).

Regarding a previous answer, setting html and body to height: 100% doesn't seem to work if the content needs to scroll. Adding fixed to the background seems to fix that - no need for height: 100%;

E.g.:

body {
  background: -webkit-gradient(linear, left top, left bottom, from(#fff), to(#cbccc8)) fixed;
}

I know I'm late to the party, but here's a more solid answer.

All you need to do is use min-height: 100%; rather than height: 100%; and your gradient background will extend the entire height of the viewport without repeating, even if the content is scrollable.

Like this:

html {
    min-height: 100%;
}

body {
    background: linear-gradient(#ff7241, #ff4a1f);
}