.button {
   /* -fx-font-size: 40; */
    -fx-background-image: url("red-rectangle.png");
    -fx-background-size: 50% 50%;
    -fx-border-color: red;
    
/*    -fx-background-size: 300% 300%;
      -fx-background-size: 100% auto;
      -fx-background-size: 100% 100%;
*/
/*
      -fx-background-size: contain;
      -fx-background-repeat: no-repeat;
      -fx-background-position: center;
*/

}