function togglePlayer1() {
  if (document.getElementById('player1').style.display == 'block') {
    document.getElementById('player1').style.display = 'none';
  }
  else {
    document.getElementById('player1').style.display = 'block';
  }
}

function togglePlayer2() {
  if (document.getElementById('player2').style.display == 'block') {
    document.getElementById('player2').style.display = 'none';
  }
  else {
    document.getElementById('player2').style.display = 'block';
  }
}

function toggleMedia (extension, id) {
  if (extension == 'mp3') {
    if (document.getElementById(id).style.display == 'block') {
      document.getElementById(id).style.display = 'none';
    }
    else {
      document.getElementById(id).style.display = 'block';
    }
  }
}

function checkForOther() {
  if (document.forms[0].referred_from.value == "other") {
    document.forms[0].other.style.display = "block";
  }
  else {
    document.forms[0].other.style.display = "none";
  }
}