function expandRight() {
  var obj = element("expand_link");
  var area_content = element("area_content");
  var area_right = element("area_right");

  if (obj.className == "right_expanded") {
    if (area_content.offsetHeight < area_right.offsetHeight ) {
      area_content.style.height = area_right.offsetHeight + "px";
    }

    obj.title = "zmenšit prostor pro obsah";
    setCookie("expanded_status", "collapsed", 1);
    setCookie("expanded_content_height", area_content.offsetHeight, 1);
  } else {
    area_content.style.height = getCookie("expanded_content_height") + "px";
    obj.title = "zvětšit prostor pro obsah";
    setCookie("expanded_status", "", 1);
    setCookie("expanded_content_height", "", 1);
 }
  
  switchClasses();
}

function switchClasses() {
  switchClass("mid", "right_expanded", "right_collapsed");
  switchClass("area_content", "right_expanded", "right_collapsed");
  switchClass("area_right", "right_expanded", "right_collapsed");
  switchClass("expand_link", "right_expanded", "right_collapsed");
}
function visibility(obj_id, folder_obj) {
  var obj = document.getElementById("folder_content_" + obj_id);

  if (obj) {
    if (obj.className == "dis_block") {
      obj.className  = "dis_none";
    } else {
      obj.className = "dis_block";
    }
  }

  if (folder_obj.className == "hand folder_closed") {
    folder_obj.className = "hand folder_open";
  } else {
    folder_obj.className = "hand folder_closed";
  }
}
var slide_show_counter = 1;
var slide_show_running = true;

/**
 * run image slideshow
 *         
 * @return void
 */
function slideShowRun() {
  for (var i=1;i<8;i++) {
    if (Math.random() > 0.5) {
      document.getElementById("slide_img_" + i).className = "slide_display";
    } else {
      document.getElementById("slide_img_" + i).className = "slide_hide";
    }
  }
  
  slide_show_counter++;
	
  if (slide_show_counter > 4) {
    slide_show_counter = 1;
  }
	
  if (!slide_show_running) {
    slide_show_running = true;
  }
	
  var t = setTimeout('slideShowRun()', slide_show_speed);
}