html { 
    background: url(../img/bg.jpg) no-repeat center center fixed; 
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}

body {
    background-color: transparent !important;
}

.vh100 {
    min-height: 100vh;
    padding-top: 100px;
    padding-bottom: 100px;
    background-color: rgba(255,255,255,0.5);
}

.clear {
    clear: both;
    display: block;
}

.spacer {
    height: 40px;
}

img {
    max-width: 100%;
    height: auto;
}