function imgon(imgName){
document[imgName].src = eval(imgName + "_02.src");
}

function imgoff(imgName){
document[imgName].src = eval(imgName + "_01.src");
}

home_01 = new Image();
home_01.src = "assets/home_off.gif";

home_02 = new Image();
home_02.src = "assets/home_on.gif";

catalogs_01 = new Image();
catalogs_01.src = "assets/catalogs_off.gif";

catalogs_02 = new Image();
catalogs_02.src = "assets/catalogs_on.gif";

careers_01 = new Image();
careers_01.src = "assets/careers_off.gif";

careers_02 = new Image();
careers_02.src = "assets/careers_on.gif";

profile_01 = new Image();
profile_01.src = "assets/profile_off.gif";

profile_02 = new Image();
profile_02.src = "assets/profile_on.gif";

lit_01 = new Image();
lit_01.src = "assets/lit_off.gif";

lit_02 = new Image();
lit_02.src = "assets/lit_on.gif";

store_01 = new Image();
store_01.src = "assets/store_off.gif";

store_02 = new Image();
store_02.src = "assets/store_on.gif";

products_01 = new Image();
products_01.src = "assets/products_off.gif";

products_02 = new Image();
products_02.src = "assets/products_on.gif";

contact_01 = new Image();
contact_01.src = "assets/contact_off.gif";

contact_02 = new Image();
contact_02.src = "assets/contact_on.gif";

news_01 = new Image();
news_01.src = "assets/news_off.gif";

news_02 = new Image();
news_02.src = "assets/news_on.gif";