Fixed gradient background with css

Question

I would like for my page to have a gradient background flowing from top to bottom. I want the background to act like a fixed image in that the gradient stretches from the to

Answer 1

Another way of doing this (with actual image):

body {
  background-attachment: local; // or 'fixed' here
  background-image: url(fancy.jpg);
  background-size: 100% 100%;
  overflow:auto;
  box-sizing:border-box;
  width:100%;
  height:100%;
  margin:0; 
}