function TCS_link () {

  location.href='index.php?' + document.getElementById('termek_csoportok').options[document.getElementById('termek_csoportok').selectedIndex].value;
}

function Search () {

  location.href='kereses.php?key=' + document.getElementById('kereses_key').value;
}

function Megrendeles (id) {

  PopUp = window.open('megrendeles.php?id=' + id, 'popupwindow', 'left=100,top=100,width=450,height=320,toolbar=0,resizable=0');
}

function TechSpec (img) {

  PopUp = window.open('techspec.php?img=' + img, 'popupwindow', 'toolbar=0,resizable=0');
}

function check_form () {

  var err_txt = "A csillaggal jelölt mezők kitöltése kötelező!";

  if ((document.rendeles.nev.value.length > 4) && (document.rendeles.telefon.value.length >= 7)) {
    return true;
  }
  else {
    alert(err_txt);
    return false;
  }
}

function Collapse(id) {

    block = document.getElementById('collapse' + id); 
    if(block.style.display == 'block'){
      block.style.display = 'none';
    }else{
      block.style.display = 'block';
    }
}