function switchNav(navIndex)
{
    closeAll();
    
    switch (navIndex)
    {
        case 0:
        document.getElementById('liAbout').className='selected';
        document.getElementById('about').className = 'lightbox';
        fadeIn('about',0);
        break;

        case 1:
        document.getElementById('liTrailer').className='selected';
        document.getElementById('trailer').className = 'lightbox';
        
        document.getElementById('logotext').style.position = 'relative';
        document.getElementById('logotext').style.top = '60px';
        document.getElementById('logotext').style.left = '50px';

        document.getElementById('footer').style.position = 'relative';
        document.getElementById('footer').style.top = '60px';
        document.getElementById('footer').style.left = '50px';

        break;

        case 2:
        document.getElementById('liPurchase').className='selected';
        document.getElementById('purchase').className = 'lightbox';
        fadeIn('purchase',0);
        break;

        case 3:
        document.getElementById('liContact').className='selected';
        document.getElementById('contact').className = 'lightbox';
        fadeIn('contact',0);
        break;
        
        case 4:
        document.getElementById('aboutcompany').className = 'lightbox';
        fadeIn('aboutcompany',0);
        break;
        
        default:
        break;
    }
}

function fadeIn(objId,opacity) {
  if (document.getElementById) {
    obj = document.getElementById(objId);
    if (opacity < 84) {
      setOpacity(obj, opacity);
      opacity += 7;
      window.setTimeout("fadeIn('"+objId+"',"+opacity+")", 30);
    }
  }
}

function fadeOut(objId,opacity) {
    if (opacity > 0) {
      setOpacity(obj, opacity);
      opacity -= 7;
      window.setTimeout("fadeOut('"+objId+"',"+opacity+")", 30);
    } else {
        closeAll();
    }
}