How can I get custom background picture to extend to the whole form?

My form is a long and goes beyond the background picture.  I don't want the picture to repeat.  Instead I would like the picture to extend to be behind the entire form.  Thank you for the assistance.

Please inject the following code in the INJECT CSS section

.supernova body {

 background-image: url("https://www.jotform.com/uploads/darrinaraki/form_files/Honolulu_pic1.jpg");

 -webkit-background-size: cover;

 -moz-background-size: cover;

 -o-background-size: cover;

  background-size: cover;

}

This will allow the background appear to be stretched in almost all the browsers

This is how the page should appear after applying the code

That did the trick. Thank you very much!
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