function BrowserCheck() {
    var os= navigator.platform
    if (os.indexOf("Mac")!=-1) {
     this.os = "mac"
    } else {
     this.os = "pc"
    }
 var b = navigator.appName
 if (b=="Netscape") this.b = "ns"
 else if (b=="Microsoft Internet Explorer") this.b = "ie"
 else this.b = b
 this.v = parseInt(navigator.appVersion)
 this.ns = (this.b=="ns" && this.v>=4)
 this.ns4 = (this.b=="ns" && this.v==4)
 this.ns5 = (this.b=="ns" && this.v==5)
 this.ns6 = (this.b=="ns" && this.v==6)
 this.ie = (this.b=="ie" && this.v>=4)
 this.ie4 = (navigator.userAgent.indexOf('MSIE 4')>0)
 this.ie5 = (navigator.userAgent.indexOf('MSIE 5')>0)
 if (this.ie5) this.v = 5
 this.min = (this.ns||this.ie)
}
// automatically create the "is" object
is = new BrowserCheck();

var min_windowheight = 578;

function getWindowHeight() {
 if(this.ie)  {
   this.windowheight = top.document.body.offsetHeight;
 } else {
   this.windowheight = top.innerHeight;
 }
}