www.mozilla.org/en-US/firefox/13.0/releasenotes/

<span class="tag tag-new">NEW</span>

#firefox-notes .tag-new {
    background-color: #FFEDCF;
}
#firefox-notes .tag-changed {
    background-color: #E9CFFF;
    background-position: -150px 50%;
}
#firefox-notes .tag-fixed {
    background-color: #F0FFE1;
    background-position: -300px 50%;
}
#firefox-notes .tag-html5 {
    background-color: #F8DFD8;
    background-position: -450px 50%;
}
#firefox-notes .tag-resolved {
    background-color: #DCF6FF;
    background-position: -600px 50%;
}
#firefox-notes .tag-unresolved {
    background-color: #FFC8C8;
    background-position: -750px 50%;
}
#firefox-notes .tag-developer {
    background-color: #E7E7E7;
    background-position: -900px 50%;
}

#firefox-notes .tag {
    background: url("/img/covehead/firefox/aurora/relnotes/tags.png") no-repeat scroll 0 50% #999999;
    border-bottom-left-radius: 2px;
    border-top-left-radius: 2px;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1), 0 -1px 0 rgba(0, 0, 0, 0.2) inset;
    color: #383838;
    display: inline-block;
    font-family: "Open Sans",sans-serif;
    font-size: 11px;
    font-style: normal;
    left: 0;
    line-height: 22px;
    min-width: 85px;
    padding: 0 15px 0 20px;
    position: absolute;
    text-align: right;
    text-shadow: 1px 1px 0 #FFFFFF;
    text-transform: uppercase;
    top: 12px;
    width: 85px;
}