JS printing interface CSS center code for all browsers

 
function preview(oper) { 
if (oper < 10) { 
bdhtml = window.document.body.innerHTML;//Gets the HTML code for the current page
sprnstr = "<!--startprint" + oper + "-->";//Set the print start area
eprnstr = "<!--endprint" + oper + "-->";//Set the end of print area
prnhtml = bdhtml.substring(bdhtml.indexOf(sprnstr) + 18); //Fetch the HTML back from the starting code

prnhtml = prnhtml.substring(0, prnhtml.indexOf(eprnstr));//Fetch the HTML forward from the closing code
window.document.body.innerHTML = prnhtml; 
window.print(); 
window.document.body.innerHTML = bdhtml; 
} else { 
window.print(); 
} 

} 
#outer { 
display:table; 
height:400px; 
#position:relative; 
overflow:hidden; 
} 
#middle { 
display:table-cell; 
vertical-align:middle; 
#position:absolute; 
#top:50%; 
} 
#inner { 
#position:relative; 
#top:-50%; 
} 



<div id= " outer " > 
<div id= " middle " > 
<div id= " inner " > 
<! Here is the vertically centered content > 
</div> 
</div> 
</div>