// Preload navigation rollovers
var nav_home_off = new Image();
nav_home_off.src = '../../../images/nav_home_off.gif';

var nav_home_on = new Image();
nav_home_on.src = '../../../images/nav_home_on.gif';

var nav_about_off = new Image();
nav_about_off.src = '../../../images/nav_about_off.gif';

var nav_about_on = new Image();
nav_about_on.src = '../../../images/nav_about_on.gif';

var nav_news_off = new Image();
nav_news_off.src = '../../../images/nav_news_off.gif';

var nav_news_on = new Image();
nav_news_on.src = '../../../images/nav_news_on.gif';

var nav_preserves_off = new Image();
nav_preserves_off.src = '../../../images/nav_preserves_off.gif';

var nav_preserves_on = new Image();
nav_preserves_on.src = '../../../images/nav_preserves_on.gif';

var nav_resources_off = new Image();
nav_resources_off.src = '../../../images/nav_resources_off.gif';

var nav_resources_on = new Image();
nav_resources_on.src = '../../../images/nav_resources_on.gif';

var navPrefix = 'nav_';

function rollOver(id) {
	document.images[id].src = eval(id + '_on.src');
}

function rollOut(id) {
	document.images[id].src = eval(id + '_off.src');
}

function rollNavOver(id) {
	rollOver(navPrefix + id);
}

function rollNavOut(id) {
	rollOut(navPrefix + id);
}