function Cover( params )
{
	params = params ? params : new Array();
	this.z = params.z ? params.z : 10000;
	this.color = params.color ? params.color : "#6699cc";
	this.transparency = params.transparency && params.transparency >= 1 && params.transparency <= 100 ? params.transparency : 70;
	this.target = params.target ? params.target : document.body;
	
	this.obj = document.createElement("div");
	var style = this.obj.style;
	style.position = "absolute";
	style.display = "none";
	style.zIndex = this.z;
	style.top = 0;
	style.left = 0;
	style.backgroundColor = this.color;
	style.filter = "alpha(opacity=" + this.transparency + ")";
	style.opacity = this.transparency / 100;
	style.MozOpacity = this.transparency / 100;
	
	this.target.appendChild( this.obj );
}
Cover.prototype.show = function()
{
	this.obj.style.height = this.target.scrollHeight + "px";
	this.obj.style.width = this.target.clientWidth + "px";
	
	this.obj.style.display = "block";
}
Cover.prototype.hide = function()
{
	this.obj.style.display = "none";
}