site-credits.css

/*
** Site Credits
*/
#site-credits {
  text-align: right;
  font-size: 12px;
}
#site-credits a {
  border: 1px solid transparent;
  margin-right: -11px;
  padding: 0 4px 0 6px;
  text-transform: uppercase;
  color: #00dcff;
}
#site-credits a:focus,
#site-credits a:active,
#site-credits a:hover {
  color: #00dcff;
  text-decoration: none;
  border: 1px solid;
  -webkit-animation:rainbow 1s infinite;
  -ms-animation:rainbow 1s infinite;
  -o-animation:rainbow 1s infinite;
  animation:rainbow 1s infinite;
}
@-webkit-keyframes rainbow {
0% {color: #ff0000;}
10% {color: #ff8000;}
20% {color: #ffff00;}
30% {color: #80ff00;}
40% {color: #00ff00;}
50% {color: #00ff80;}
60% {color: #00ffff;}
70% {color: #0080ff;}
80% {color: #0000ff;}
90% {color: #8000ff;}
100% {color: #ff0080;}
}
@-ms-keyframes rainbow {
0% {color: #ff0000;}
10% {color: #ff8000;}
20% {color: #ffff00;}
30% {color: #80ff00;}
40% {color: #00ff00;}
50% {color: #00ff80;}
60% {color: #00ffff;}
70% {color: #0080ff;}
80% {color: #0000ff;}
90% {color: #8000ff;}
100% {color: #ff0080;}
}
@-o-keyframes rainbow {
0% {color: #ff0000;}
10% {color: #ff8000;}
20% {color: #ffff00;}
30% {color: #80ff00;}
40% {color: #00ff00;}
50% {color: #00ff80;}
60% {color: #00ffff;}
70% {color: #0080ff;}
80% {color: #0000ff;}
90% {color: #8000ff;}
100% {color: #ff0080;}
}
@keyframes rainbow {
0% {color: #ff0000;}
10% {color: #ff8000;}
20% {color: #ffff00;}
30% {color: #80ff00;}
40% {color: #00ff00;}
50% {color: #00ff80;}
60% {color: #00ffff;}
70% {color: #0080ff;}
80% {color: #0000ff;}
90% {color: #8000ff;}
100% {color: #ff0080;}
}

site-credits.html

<div id="site-credits">
	<a href="http://www.kmpiekarski.com/" target="_blank">site by k.m.piekarski</a>
</div>