.pantalla{
		    display: -webkit-flex;
		    display: flex;
		    -webkit-flex-direction: column;
		    flex-direction: column;
		    /*width: 500px;*/
		    padding: 10px;
		    border: 0px;
		    margin: 0px;
		    background-color:#E9E6E6  ;
		 }
		 .pantalla input[type=text] {
		    padding: 5px 5px;
		    margin: 1px;
		    box-sizing: border-box;
		    border: none;
		    background-color: #3CBC8D;
		    color: white;
		    font: bold 1.5em/1.5em HelveticaNeue, Arial;
		    -webkit-align-self: center;
		    align-self: center;
		    width: 650px;
		 }
		 .teclas{
		    -webkit-flex-direction: column;
		    flex-direction: column;
		    padding: 5px;
		    border: 0px;
		    margin: 0px;
		    background-color:transparent;
		    -webkit-align-self: center;
		    align-self: center;
		 }
		 .teclas button { 
		    border: 1px solid #dedede;
		    border-radius: 3px;
		    color: #555;
		    display: inline-block;
		    font: bold 1.5em/1.5em HelveticaNeue, Arial;
		    padding: 0px 0px;
		    text-decoration: none;
		    width: 100px;
		    height:70px;
		    background: #f5f5f5;
		    border-color: #dedede #d8d8d8 #d3d3d3;
		    box-shadow: 0 1px 1px #eaeaea, inset 0 1px 0 #fbfbfb;
		    color: #555;
		    text-shadow: 0 1px 0 #fff;
		    background: -moz-linear-gradient(top,  #f9f9f9, #f0f0f0);
		    background: -webkit-linear-gradient(top,  #f9f9f9, #f0f0f0);
		    background: o-linear-gradient(top,  #f9f9f9, #f0f0f0);
		    background: ms-linear-gradient(top,  #f9f9f9, #f0f0f0);
		    background: linear-gradient(top,  #f9f9f9, #f0f0f0);
		    filter:  progid:DXImageTransform.Microsoft.gradient(startColorstr='#f9f9f9', endColorstr='#f0f0f0');
		 }
		 .teclas button:hover{
		      background: #f4f4f4;
		      border-color: #c7c7c7 #c3c3c3 #bebebe;
		      box-shadow: 0 1px 1px #ebebeb, inset 0 1px 0 #f3f3f3;
		      text-shadow: 0 1px 0 #fdfdfd;
		      background: -moz-linear-gradient(top,  #efefef, #f8f8f8);
		      background: -webkit-linear-gradient(top,  #efefef, #f8f8f8);
		      background: -o-linear-gradient(top,  #efefef, #f8f8f8);
		      background: -ms-linear-gradient(top,  #efefef, #f8f8f8);
		      background: linear-gradient(top,  #efefef, #f8f8f8);
		      filter:  progid:DXImageTransform.Microsoft.gradient(startColorstr='#efefef', endColorstr='#f8f8f8');
		 }