//funkcje rollover
function rollover(e) {
 if (!e) {
  var e = window.event;
 }
 var whichButton = (e.target) ? e.target.id : e.srcElement.id;
 var objectButton = document.getElementById(whichButton);
 
 objectButton.src = "_images/" + whichButton + "-g.png";

}
function deRollover(e) {
 if (!e) {
  var e = window.event;
 }
 var whichButton = (e.target) ? e.target.id : e.srcElement.id;
 var objectButton = document.getElementById(whichButton);
 
 objectButton.src = "_images/" + whichButton + ".png";
}

buttons = document.getElementsByClassName('button');
for (i = 0; i < 7; i++) {
	buttons[i].onmouseover = rollover;
	buttons[i].onmouseout = deRollover;
}

currentButton = document.getElementsByClassName('currentbutton');

imgName = currentButton[0].id;
currentButton[0].src = "_images/" + imgName + "-g.png";;