if (document.images) { 

//index_category

var img0on = new Image();
img0on.src = "images/navi00_01on.gif";
var img0off = new Image();
img0off.src = "images/navi00_01off.gif";

var img1on = new Image();
img1on.src = "images/navi01_01_on.gif"; 
var img1off = new Image();
img1off.src = "images/navi01_01_off.gif";

var img2on = new Image();
img2on.src = "images/navi01_02_on.gif";
var img2off = new Image();
img2off.src = "images/navi01_02_off.gif";

var img3on = new Image();
img3on.src = "images/navi01_03_on.gif";
var img3off = new Image();
img3off.src = "images/navi01_03_off.gif";

var img4on = new Image();
img4on.src = "images/navi01_04_on.gif";
var img4off = new Image();
img4off.src = "images/navi01_04_off.gif";

var img5on = new Image();
img5on.src = "images/navi01_05_on.gif";
var img5off = new Image();
img5off.src = "images/navi01_05_off.gif";

var img6on = new Image();
img6on.src = "images/navi01_06_on.gif";
var img6off = new Image();
img6off.src = "images/navi01_06_off.gif";

var img7on = new Image();
img7on.src = "images/navi02_01_on.gif";
var img7off = new Image();
img7off.src = "images/navi02_01_off.gif";

var img8on = new Image();
img8on.src = "images/navi02_02_on.gif";
var img8off = new Image();
img8off.src = "images/navi02_02_off.gif";

var img9on = new Image();
img9on.src = "images/navi02_03_on.gif";
var img9off = new Image();
img9off.src = "images/navi02_03_off.gif";

var img10on = new Image();
img10on.src = "images/navi02_04_on.gif";
var img10off = new Image();
img10off.src = "images/navi02_04_off.gif";

var img11on = new Image();
img11on.src = "images/navi02_05_on.gif";
var img11off = new Image();
img11off.src = "images/navi02_05_off.gif";

var img12on = new Image();
img12on.src = "images/navi03_01_on.gif";
var img12off = new Image();
img12off.src = "images/navi03_01_off.gif";

} 


function On(name) { 

if (document.images) { 
document.images[name].src = eval(name + 'on.src'); 
} 

} 


function Off(name) { 

if (document.images) { 
document.images[name].src = eval(name + 'off.src'); 
} 

}