change span vertically in full page js code example

Example 1: how to make gradient backgroud cover whole page in html

/*Basically, add html height 100%. This will stretch your gradient.*/
html {
  height:100%;
}

body {
  background-image: /* put gradient here */;
  background-repeat: no-repeat;
}

Example 2: how to change the height of an image in html

<img src="smiley.gif" alt="Smiley face" height="42" width="42">