.my_btn {
opacity: 0.8;
    filter: alpha(opacity=50); /* For IE8 and earlier */
 
     margin-bottom:20px;
}

.my_btn:hover {
    max-width:95%;
    opacity: 1.0;
    filter: alpha(opacity=50); /* For IE8 and earlier */
 
  
  /*border:2px solid #ff0000;*/
}