html, body{
height:100%;
width:100%;
}

.contenido{
position:fixed;
display:inline-block;
top: 50%;
left: 50%;
width:25em;
margin-top: -14em; /*set to a negative number 1/2 of your height*/
margin-left: -12em;
}

.contenido .logo{
width:100%;
height:9em;
margin:0;
background:url(../images/logo.png) center center no-repeat;
background-size:80% 80%;
background-color:rgba(166,166,166,0.6);
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
}

.contenido .lgcntainer{
width:100%;
background-color:rgba(0,0,0,0.4);
padding:3em;
display:inline-block;
-webkit-border-bottom-right-radius: 5px;
-webkit-border-bottom-left-radius: 5px;
-moz-border-radius-bottomright: 5px;
-moz-border-radius-bottomleft: 5px;
border-bottom-right-radius: 5px;
border-bottom-left-radius: 5px;
}

form .input-group{
margin-bottom:1em;
height:3em;
}

form .input-group input{
height:3em;
}

.buttons, a:hover{
background-color:#252426;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;
padding:0.6em;
width:100% !important;
margin-top:1em;
display:inline-block;
font-size:1.2em;
text-align:center;
color:#fff;
text-decoration:none;
}

a:hover{
background-color:#49464A;
}