body {
    font:Times,"Times New Roman",serif;
    color:#000;background-color:#fff;
    font-size:18px;
    max-width:1000px;
    padding-top:5ex;
    padding-bottom:5ex;
    padding-left:5vw;
    padding-right:5vw;
    margin:auto
}
img {
    max-width:100%;
    vertical-align:middle
}
.ref {
    margin-left:20px
}