function li_change_img(img_id, img_src, img_caption_id, img_caption_id_switch){

  var x = document.getElementById(img_id).src = img_src;
  var y = document.getElementById(img_caption_id).innerHTML = document.getElementById(img_caption_id_switch).alt;
  var z = document.getElementById(img_id).alt = document.getElementById(img_caption_id_switch).alt;

}

function show_section(section_id){

  document.getElementById('lis-photos').style.display='none';
  document.getElementById('lis-contact').style.display='none';
  document.getElementById('lis-shipping').style.display='none';
  document.getElementById('lis-description').style.display='none';
  document.getElementById('lis-customize').style.display='none';

  document.getElementById(section_id).style.display='block';

  section = section_id;

}

function show_print_sections(){

  document.getElementById('lis-contact').style.display='none';
  document.getElementById('lis-shipping').style.display='none';
  document.getElementById('lis-customize').style.display='none';

  document.getElementById('lis-description').style.display='block';
  document.getElementById('lis-photos').style.display='block';

}