#btn-end{
			   visibility: hidden;
			   font-size:17px;
			   padding: 8px;
			   color: #fff;
			   font-weight: bold;
			   background-color: #04B431;
			   border: 1px #04B431;
			   border-radius: 5px;   
			 }
			 
			 #btn-end.show-btn{
			   visibility: visible;
			 }
			 
			  #btn-envio.hide-btn{
			   visibility: hidden;
			 } 
			 
			 #spinner {
			      visibility: hidden;
				  border: 10px solid #f3f3f3; /*Light grey */
				  border-top: 10px solid #3498db; /* Blue */
                  border-bottom: 10px solid #3498db;
				  border-radius: 50%;
				  width: 70px;
				  height: 70px;
				  animation: spin 2s linear infinite;
				}

				@keyframes spin {
				  0% { transform: rotate(0deg); }
				  100% { transform: rotate(360deg); }
				}
				
			  #spinner.show{
			     visibility: visible;
			  }