function playDc(pBot, pStill, pAnim) {
  if(document.getElementById(pBot).innerHTML == "play!") {
    document.getElementById(pStill).style.display = "none";
    document.getElementById(pAnim).style.display = "block";
    document.getElementById(pBot).innerHTML = "stop!"
  } else if(document.getElementById(pBot).innerHTML == "stop!") {
    document.getElementById(pStill).style.display = "block";
    document.getElementById(pAnim).style.display = "none";
    document.getElementById(pBot).innerHTML = "play!"
  }
}

function capaOculta(pCapa, pVisible)  {
  document.getElementById(pCapa).style.visibility = pVisible;
}