Prova a vedere se questo ti va bene.

Codice PHP:
<html>
    <
head>
        <
meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
        <
title>Prova</title>
        <
style media="all" type="text/css">
            
html,body
            
{
                    
margin:0px;
                    
padding:30px;
            }
            
#centralone_home
            
{
                    
width640px;
                    
height626px;
                    
marginauto;
                    
background:silver;
                    
text-align:left;
            }
            
#sponsor
            
{
                
position:absolute;
                
width175px;
                
height120px;
                
background:lightgreen;
                
margin-left:610px;
                
margin-top:50px;
            }
            
#contenitore
            
{
                
width:100%;
            }
        </
style>
    </
head>
    <
body>
        <
div id="contenitore" align="center">
            <
div id="centralone_home">
                <
div id="sponsor">SPONSOR</div>
            
CENTRALE
            
</div>
        </
div>
    </
body>
</
html