Create transparent div, one css property are used for all recent browser...(like chrome,IE, Firefox ,etc)
That is 'Opacity:0.4;' u can also able to increase or decrease the opacity value...

.transparent
{
opacity:0.4;
background-color:green;

}
<div class="transparent">San2.yed@gmail.com</div>
If any  browser not supported ..comment here...