placering af "showbox funktion"

Hej

Kan jeg udvide denne "position:absolute" funktionen så den box der kommer frem altid bliver vist inden for skærmens ramme

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<br>6. <a href="http://www.newfashionstyle.com/images/Din_Egen_Tekst.gif" onmouseover="showURL(this);showBox(530,600,event);" onmouseout="hideBox()" onclick="return false;">Din egen tekst</a> (max. 6 linier)
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<hr>
<span style="font-size:x-small;font-weight:bold;">Her kan du foretage dine valg</span> (se guiden hvis du er i tvivl)</span>

<div id="minDiv" style="position:absolute;border:2px ridge #222;display:none;overflow:hidden;"><iframe id="minIframe" name="minIframe" src="about:blank" style="width:100%;height:100%;overflow:hidden;"></iframe></div>
<script language="javascript" type="text/javascript">
function showBox(w,h,e) {
  box = document.getElementById("minDiv").style;
  box.left = ((e.clientX) ? e.clientX:e.pageX)+15+"px";
  box.top = ((e.clientY) ? e.clientY:e.pageY)-15+"px";
  box.width = w + 'px';
  box.height = h + 'px';
  box.display = "block";
}
function hideBox(){
  document.getElementById("minDiv").style.display = 'none';
}
function showURL(link){
  window.minIframe.location.href = link.href;
}
</script>
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