how to fit background image size in css code example

Example 1: background image size css

#example1 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: auto;
}

#example2 {
  background: url(mountain.jpg);
  background-repeat: no-repeat;
  background-size: 300px 100px;
}

Example 2: background image height and width

.class{
	background: url("../images/icons/map.png") no-repeat center center/50px 50px fixed;
}