html, body, center {
    height: 100%;
    background: #ffffff; /* Old browsers */
    background: -moz-linear-gradient(top, #ffffff 0%, #c4c4c4 100%, #bfbfbf 100%); /* FF3.6-15 */
    background: -webkit-linear-gradient(top, #ffffff 0%,#c4c4c4 100%,#bfbfbf 100%); /* Chrome10-25,Safari5.1-6 */
    background: linear-gradient(to bottom, #ffffff 0%,#c4c4c4 100%,#bfbfbf 100%); /* W3C, IE10+, FF16+, Chrome26+, Opera12+, Safari7+ */
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#bfbfbf',GradientType=0 ); /* IE6-9 */
}

h1 {
    width: 100%;
    font-size: 3.5em;
}

p {
    font-size: 1.3em;
}

.center {
    top: 30vh;
    position: fixed;
    text-align: center;
    width: 100%;
}