function hide(thing) {document.getElementById(thing).style.visibility = 'hidden';}
function view(thing) {document.getElementById(thing).style.visibility = 'visible';}

/* Functions */
function toggle(thing) {
  if (document.getElementById(thing).style.visibility != 'visible') {view(thing);}
  else if (document.getElementById(thing).style.visibility != 'hidden') {hide(thing);}
  }