<!--

        function change(ObjectName, ChangeTo)
        {
          document[ObjectName].src = eval(ObjectName + ChangeTo + ".src");
        }

        _on = new Image(20,35);
        _on.src = "img/logos/_on.gif";
        _off = new Image(20,35);
        _off.src = "img/logos/_off.gif";

        xon = new Image(20,35);
        xon.src = "img/logos/xon.gif";
        xoff = new Image(20,35);
        xoff.src = "img/logos/xoff.gif";

        hlzoneout = new Image(150,24);
        hlzoneout.src = "../global/img/buttons/hlzoneout.gif";
        hlzonein = new Image(150,24);
        hlzonein.src = "../global/img/buttons/hlzonein.gif";

        hlout = new Image(150,24);
        hlout.src = "../global/img/buttons/hlout.gif";
        hlin = new Image(150,24);
        hlin.src = "../global/img/buttons/hlin.gif";

        hl2out = new Image(150,24);
        hl2out.src = "../global/img/buttons/hl2out.gif";
        hl2in = new Image(150,24);
        hl2in.src = "../global/img/buttons/hl2in.gif";

        eoneout = new Image(150,24);
        eoneout.src = "../global/img/buttons/eoneout.gif";
        eonein = new Image(150,24);
        eonein.src = "../global/img/buttons/eonein.gif";

        etwoout = new Image(150,24);
        etwoout.src = "../global/img/buttons/etwoout.gif";
        etwoin = new Image(150,24);
        etwoin.src = "../global/img/buttons/etwoin.gif";

        oppforceout = new Image(150,24);
        oppforceout.src = "../global/img/buttons/oppforceout.gif";
        oppforcein = new Image(150,24);
        oppforcein.src = "../global/img/buttons/oppforcein.gif";

        bshiftout = new Image(150,24);
        bshiftout.src = "../global/img/buttons/bshiftout.gif";
        bshiftin = new Image(150,24);
        bshiftin.src = "../global/img/buttons/bshiftin.gif";

        cstrikeout = new Image(150,24);
        cstrikeout.src = "../global/img/buttons/cstrikeout.gif";
        cstrikein = new Image(150,24);
        cstrikein.src = "../global/img/buttons/cstrikein.gif";

        cssout = new Image(150,24);
        cssout.src = "../global/img/buttons/cssout.gif";
        cssin = new Image(150,24);
        cssin.src = "../global/img/buttons/cssin.gif";

// definice obrázků v návodu

        chapter01off = new Image(150,92);
        chapter01off.src = "img/pictures/navod/chapter01off.gif";
        chapter01on = new Image(150,92);
        chapter01on.src = "img/pictures/navod/chapter01on.gif";

        chapter02off = new Image(150,92);
        chapter02off.src = "img/pictures/navod/chapter02off.gif";
        chapter02on = new Image(150,92);
        chapter02on.src = "img/pictures/navod/chapter02on.gif";

        chapter03off = new Image(150,92);
        chapter03off.src = "img/pictures/navod/chapter03off.gif";
        chapter03on = new Image(150,92);
        chapter03on.src = "img/pictures/navod/chapter03on.gif";

        chapter04off = new Image(150,92);
        chapter04off.src = "img/pictures/navod/chapter04off.gif";
        chapter04on = new Image(150,92);
        chapter04on.src = "img/pictures/navod/chapter04on.gif";

        chapter05off = new Image(150,92);
        chapter05off.src = "img/pictures/navod/chapter05off.gif";
        chapter05on = new Image(150,92);
        chapter05on.src = "img/pictures/navod/chapter05on.gif";

//-->