How make tree on Twitter Bootstrap background like

问题:

I've added the following:

body {
  background-image: url(https://twimg0-a.akamaihd.net/images/themes/theme2/bg.gif);
}

But the tree is copied several times and not fixed on the left.

回答1:

Add no-repeat (to prevent repetition), top left (to keep the image at the desired location) and fixed (to keep the image fixed when you scroll):

background: url(http://...) no-repeat top left fixed;

I have written a demo on jsFiddle.