var preloadFlag = false;
var imgName;              // nav btn over now
var thisPage;             // page loaded now
var mainNav;              // main nav btn now

function newImage(arg) {
  if (document.images) {
    rslt = new Image();
    rslt.src = arg;
    return rslt;
  }
}

function preloadImages(thisPage) {
  if (document.images && (preloadFlag == false)) {  // main nav preload
    btn1_0 = newImage("images/btn1-0.jpg");
    btn1_1 = newImage("images/btn1-1.jpg");
    btn2_0 = newImage("images/btn2-0.jpg");
    btn2_1 = newImage("images/btn2-1.jpg");
    btn3_0 = newImage("images/btn3-0.jpg");
    btn3_1 = newImage("images/btn3-1.jpg");
    btn4_0 = newImage("images/btn4-0.jpg");
    btn4_1 = newImage("images/btn4-1.jpg");
    btn5_0 = newImage("images/btn5-0.jpg");
    btn5_1 = newImage("images/btn5-1.jpg");
    btn6_0 = newImage("images/btn6-0.jpg");
    btn6_1 = newImage("images/btn6-1.jpg");
    btn7_0 = newImage("images/btn7-0.jpg");
    btn7_1 = newImage("images/btn7-1.jpg");
    //...
    preloadFlag = true;
    mainNav = thisPage;
    imgName = "btn"+mainNav;
    btn_over(imgName);
  }
 	window.status = "Kelly's Ace Hardware at Lake Chelan, Washington - phone 509.682.2815";
}

function changeImages() {
  if (document.images && (preloadFlag == true)) {
    for (var i=0; i<changeImages.arguments.length; i+=2) {
      document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
    }
  }
}

function btn_over(imgName) {  // main nav
  if (document.images && (preloadFlag == true)) {
		document[imgName].src = eval(imgName + "_1.src");
	} 
}

function btn_off(imgName) {
  if (document.images) {
		if ("btn"+mainNav != imgName) {
			document[imgName].src = eval(imgName + "_0.src");
		}
		else {
			document[imgName].src = eval(imgName + "_1.src");
		}
	}
}