body{
    background-image:url('../imagenes/foto-hph.jpg');
    background-attachment:scroll;
    background-repeat:no-repeat;
    background-color:rgba(255,255,0,0.4);
    background-size: 100%;
  }


.button {
  background-color: #4CAF50; /* Green */
  position: center ;
  border: none;
  color: white;
  padding: 15px 50px;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  cursor: pointer;
  font-size: 16px;
  -webkit-transition-duration: 0.4s; /* Safari */
  transition-duration: 0.4s;
  border-radius: 8px;
}

.button:hover{
    box-shadow: 0 12px 16px 0 rgba(0,0,0,0.24),0 17px 50px 0 rgba(0,0,0,0.19);
}

.button:active {
  background-color: #3e8e41;
  box-shadow: 0 5px #666;
  transform: translateY(4px);