html, body {
    height: 100%;
}

.jumbotron {
    background-color: #f5f5f5;
}

.panel {
    background-color: white;
    border-color: #2e6da4;
    border-radius: 20px;
}
.vertical-center {
    height: 100%;
    width: 100%;
    text-align: center;
    margin: 0 0 0 0;
}

    .vertical-center:before {
        content: " ";
        display: inline-block;
        vertical-align: middle;
        height: 100%;
    }

    .vertical-center > .container {
        max-width: 100%;
        display: inline-block;
        vertical-align: middle;
    }