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/* external links */
a[href^="http://"]
{
padding-right: 13px;
background: url(external.gif) no-repeat center right;
}

/* emails */
a[href^="mailto:"]
{
padding-right: 20px;
background: url(email.png) no-repeat center right;
}

/* pdfs */
a[href$=".pdf"]
{
padding-right: 18px;
background: url(acrobat.png) no-repeat center right;
}