a:link {text-decoration: underline;}
a:visited {text-decoration: underline;}
a:hover {text-decoration: underline;}
a:active {text-decoration: underline;}

a.nu:link {text-decoration: none;}
a.nu:visited {text-decoration: none;}
a.nu:hover {text-decoration: underline;}
a.nu:active {text-decoration: none;}