body {
    background: #2a5191;
    /* fallback for old browsers */
    background: -webkit-linear-gradient(right, #2a5191, #0B2946);
    background: -moz-linear-gradient(right, #2a5191, #0B2946);
    background: -o-linear-gradient(right, #2a5191, #0B2946);
    background: linear-gradient(to left, #2a5191, #0B2946);
    font-family: "Roboto", sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}


#bg {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    background: #EEE;
}

#trigger {
    position: absolute;
    width: 200px;
    height: 136px;
    top: 50%;
    left: 50%;
    margin: -68px 0 0 -100px;
    background: #333;
    z-index: 2;
}

#trigger:hover ~ #bg {
    background: #EE0;
}