jquery 弹出窗

<!--[if IE 6]>
<script>
    var isIE6 = true;
</script>
<style>
* html { background-image:url(about:blank); background-attachment:fixed; }
* html .mask_content { z-index: 9999; position: absolute !important; left: expression(eval(document.documentElement.scrollLeft + document.documentElement.clientWidth/2 - this.offsetWidth/2));top: expression(eval(document.documentElement.scrollTop + document.documentElement.clientHeight/2 - this.offsetHeight/2)); }
</style>
<![endif]-->
<script>
    //通用弹层
    function openLay(options) {
        var content_html_code = typeof options.content_html_code === 'undefined' ? '' : options.content_html_code,
            content_height = typeof options.height === 'undefined' ? 300 : options.height,
            content_width = typeof options.width === 'undefined' ? 400 : options.width;
                        
        var docE = document.documentElement,
            mask = jQuery('<div class="mask"/>').css({position:'absolute','z-index':999,left:'0',top:'0',opacity:'.8',filter:'alpha(opacity=80)','background-color':'#000'}),
            iframe = jQuery('<iframe />').css({position:'absolute','100%',height:'100%','z-index':-1,top:0,left:0,filter:'alpha(opacity=0)'}),
            content = jQuery('<div class="mask_content">' + content_html_code ),
            dom_content = content[0],
            dom_mask = mask[0];        
        
        mask.width(Math.max(document.body.scrollWidth,docE.scrollWidth)).height(Math.max(document.body.scrollHeight,docE.scrollHeight));
        if (typeof isIE6 !== 'boolean') {
            content.css({position:'fixed','z-index':9999,content_width,height:content_height,left:'50%',top:'50%','margin-left':-options.width/2,'margin-top':-options.height/2});

        }
        
        dom_mask.appendChild(iframe[0]);
        document.body.appendChild(dom_mask);
        document.body.appendChild(dom_content);
        
    
        
        jQuery('#mask_close').click(function(){
            jQuery('.mask_content').fadeOut(500);
            jQuery('.mask').remove();
            jQuery('.mask_content').remove();            
        })    
    }
 function removMask(){
            jQuery('.mask_content').fadeOut(500);
            jQuery('.mask').remove();
            jQuery('.mask_content').remove();    
            }