html {
    background-color: #999;
}

body {
    width: 50%;
    min-width: 640px;
    margin: 50px auto;
    padding: 10px 30px;
    background-color: #eee;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

table {
    margin: 30px auto;
    width: 70%;
    border-collapse: collapse;
}

td, th {
    border: 2px solid #69c;
    padding: 5px;
}

th {
    font-style: italic;
    background-color: #ccc;
}

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

body {
    width: 50%;
    border: 2px solid black;
    background-color: rgba( 255, 255, 255, 0.8 );
    box-shadow: 0 10px 30px rgba( 0, 0, 0, 0.7 );
    padding: 10px 30px; 
    margin: 50px auto;
}