I'm trying to centralize buttons on an interface which uses the innerHTML property

The interface looks like this: http://i.imgur.com/JVD0F9I.png

Here's the code as to where I assume the buttons call from:

Code:
function fightdelay(tstatus) {
    if (lastaction != "m" && lastaction != "t" && lastaction != "o" && lastaction != "v" && lastaction != "k2" && lastaction != "k3" && lastaction != "rf" && lastaction != "q") {
        if (mx == 1) {
            top.toiminta.attb.innerHTML = "<input type=button value=' use weapon ' id='btn_attack' name='btn_attack' onclick='top.fightAction();'>";
            top.toiminta.casb.innerHTML = "<input type=button value=' cast spell ' id='btn_cast' name='btn_cast' onclick='top.castAction();'>";
			
        }
        top.toiminta.nefb.innerHTML = "<input type=button value=' new fight ' onclick='top.newFightAction();'>";
    }
}

function delNF() {
    top.toiminta.nefb.innerHTML = "<input type=button value=' new fight ' onclick='void(#);'>";
}

function s_c() {
    top.chat.document.msg.btn_chat.disabled = true;
}

function getRandomButtonText(nbr) {
    return "...";
}

function getRandomNum() {
    var rndNum = Math.random()
    rndNum = parseInt(rndNum * 1000);
    rndNum = (rndNum % 94) + 33;
    return rndNum;
}
Take into account that this is from a game from early 2001