sample-css-code.css

#site-logo img {
    border: 1px solid #dedee0;
    background-color: #f8f6f7;
    padding: 5px;
    display: block;
    max-height: 100px;
    max-width: 100px;
    width: auto;
    margin: 0 auto;
    line-height: 0;    
    -webkit-border-radius: 50px;
       -moz-border-radius: 50px;
        -ms-border-radius: 50px;
         -o-border-radius: 50px;
            border-radius: 50px;            
}