body {
    background-image: url("../images/Yosemite.jpg");
    background-size: cover;
    background-position: top center;
    background-repeat: no-repeat;
    background-attachment: fixed;  
}

#game-header, #game-container {
    max-width: 980px;
}

.jumbotron {
    background-color: rgba(211, 211, 211, 0.75);
}

img{
    margin: auto 0;
    width: 50%;
    height: auto;
    padding: 2rem;
}