Encoded email : page changed without consent !

<style type="text/css">  
p span.displaynone { display:none; }  
</style>  
<p>ddd@<span class="displaynone">null</span>dd.com</p>

<a href=mailto:ddd@dd.com>ddd@dd.com</a>

@<span class="displaynone">null</span>