body {
    background: rgba(12, 100, 129, 1) url('https://images.cnblogs.com/cnblogs_com/Penn000/1013849/o_123.jpg') fixed no-repeat;
    background-position: 50% 5%; 
    background-size: cover;
    margin-top: 20px;
}

#top {
	background:none;
}

#sub {
	background:none;
}

#footer {
    font-size: 10px;
}