//grey out page script



  function grayOut(vis, options) {
    // Pass true to gray out screen, false to ungray
    // options are optional.  This is a JSON object with the following (optional) properties
    // opacity:0-100         // Lower number = less grayout higher = more of a blackout
    // zindex: #             // HTML elements with a higher zindex appear on top of the gray out
    // bgcolor: (#xxxxxx)    // Standard RGB Hex color code
    // grayOut(true, {'zindex':'50', 'bgcolor':'#0000FF', 'opacity':'70'});
    // Because options is JSON opacity/zindex/bgcolor are all optional and can appear
    // in any order.  Pass only the properties you need to set.
    var options = options || {};
    var zindex = options.zindex || 50;
    var opacity = options.opacity || 70;
    var opaque = (opacity / 100);
    var bgcolor = options.bgcolor || '#000000';
    var dark=document.getElementById('darkenScreenObject');


    if (!dark) {
      // The dark layer doesn't exist, it's never been created.  So we'll
      // create it here and apply some basic styles.
      // If you are getting errors in IE see: http://support.microsoft.com/default.aspx/kb/927917
      var tbody = document.getElementsByTagName("body")[0];
      var tnode = document.createElement('div');           // Create the layer.
          tnode.style.position='absolute';                 // Position absolutely
          tnode.style.top='0px';                           // In the top
          tnode.style.left='0px';                          // Left corner of the page
          tnode.style.overflow='hidden';                   // Try to avoid making scroll bars
          tnode.style.display='none';                      // Start out Hidden
          tnode.id='darkenScreenObject';                   // Name it so we can find it later
      tbody.appendChild(tnode);                            // Add it to the web page
      dark=document.getElementById('darkenScreenObject');  // Get the object.
    }

    if (vis) {
      // Calculate the page width and height
      if( document.body && ( document.body.scrollWidth || document.body.scrollHeight ) ) {
          var pageWidth = document.body.scrollWidth+'px';
          var pageHeight = document.body.scrollHeight+'px';
      } else if( document.body.offsetWidth ) {
        var pageWidth = document.body.offsetWidth+'px';
        var pageHeight = document.body.offsetHeight+'px';
      } else {
         var pageWidth='100%';
         var pageHeight='100%';
      }
    //set the shader to cover the entire page and make it visible.
    dark.style.opacity=opaque;
    dark.style.MozOpacity=opaque;
    dark.style.filter='alpha(opacity='+opacity+')';
    dark.style.zIndex=zindex;
    dark.style.backgroundColor=bgcolor;
    dark.style.width= pageWidth;
    dark.style.height= pageHeight;
    dark.style.display='block';
    } else {
       dark.style.display='none';
    }
  }


  function popUpSysRequirements(divObj){
    var pageWidth=0;
  	var pageHeight=0;

    if(document.body.scrollWidth || document.body.scrollHeight) {
          pageWidth = document.body.scrollWidth;
          pageHeight = document.body.scrollHeight;
    }else{
          pageWidth = document.body.offsetWidth;
          pageHeight = document.body.offsetHeight;
    }
    var divWidth = 645;
    var divHeight = 500;
    //var divWidth = divObj.offsetWidth;
    //var divHeight = divObj.scrollHeight;

    var leftWidth = (pageWidth - divWidth)/2;
    var topHeight = (pageHeight - divHeight)/2;
	//alert("offsetWidth: " + divWidth + "\noffsetHeight: "+ divHeight +"\npageWidth: " + pageWidth +"\npageHeight: " +
    //    + pageHeight + "\nleftWidth: " + leftWidth + "\ntopHeight: " + topHeight);

    grayOut(true);

    divObj.style.left = leftWidth + 'px';
    divObj.style.top =  topHeight + 'px';
    divObj.style.display = "block";
  }
  function closeSysRequirements(divObj){
    grayOut(false);
    divObj.style.display = "none";
  }