how to center a button with css and html

[komarovi]

i want to center one button up and the other down. how can i edit my css to achieve this.here is css-\[code\]#ContactForm .button {margin-left:8px;margin-left:9px;float:right;margin-right:2px;font-size:20px;font-weight:700;color:#fff;line-height:35px;width:90px;text-align:center;background:url(../images/button_form.gif) top repeat-x #308da2;border-radius:10px;-moz-border-radius:10px;-webkit-border-radius:10px;behavior:url(js/PIE.htc);position:relative;text-decoration:none}\[/code\]html-\[code\]<div> <a href="http://stackoverflow.com/questions/13836059/#" class="button" onclick="document.getElementById('ContactForm').submit()">send</a> <a href="http://stackoverflow.com/questions/13836059/#" class="button" onclick="document.getElementById('ContactForm').reset()">clear</a></div>\[/code\]