css background image size

#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;
}background-size: 100px 50px; /* 100px wide, 50px tall */    #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;
} body {
  background-position: center;
  background-repeat: no-repeat;
  background-size: contain;
}Background image resize