#install-btn {
    background: #0088cc; /* Old browsers */
    background: -moz-linear-gradient(top,  #0088cc 0%, #0055cc 100%); /* FF3.6+ */
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#0088cc), color-stop(100%,#0055cc)); /* Chrome,Safari4+ */
    background: -webkit-linear-gradient(top,  #0088cc 0%,#0055cc 100%); /* Chrome10+,Safari5.1+ */
    background: -o-linear-gradient(top,  #0088cc 0%,#0055cc 100%); /* Opera 11.10+ */
    background: -ms-linear-gradient(top,  #0088cc 0%,#0055cc 100%); /* IE10+ */
    background: linear-gradient(to bottom,  #0088cc 0%,#0055cc 100%); /* W3C */
    filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#0088cc', endColorstr='#0055cc',GradientType=0 ); /* IE6-9 */

    text-align: center;
    font-size: 200%;
    margin: 1em auto;
    display: block;
    padding: .5em;
    color: white;
    width: 10em;
    max-width: 80%;
    line-height: 1.2em;
}