v-course.js

$(document).ready(function() {
   $('#toc ~ #content-text > div > h1').removeAttr('class');
   $('#toc ~ #content-text > div > h1 > span').removeAttr('class');
   $('#toc ~ #content-text > div > h2').removeAttr('class');
   $('#toc ~ #content-text > div > h2 > span').removeAttr('class');
   $('#toc .h3, #toc .h4, #toc .h5, #toc .h6').remove();
   $('#toc .h1 > span, #toc .h2 > span').removeAttr('class');
   $('#toc ~ #content-text > table').prev().remove();
   var startsWithEnglish = /^English/;
   $('table tr:nth-child(1) td:nth-child(1):contains("English")')
      .filter(function () {
        return startsWithEnglish.test($.trim($(this).text()));
      })
      .parent()
      .addClass('v-theader');
   embedYoutubeLinks();
});

function embedYoutubeLinks() {
  var ytLinks = $('#content-text a[href*="https://youtu"], #content-text a[href*="https://www.youtu"]');
  ytLinks.each(function(){
     var ytUri = $(this).text();
     var videoId = url('?v', ytUri) || url('1', ytUri);
     var iframe = document.createElement('iframe');
     iframe.src = 'https://www.youtube.com/embed/' + videoId +'? cc_lang_pref=cat&hl=cat&modestbranding=1&rel=0&cc_lang_pref=cat&hl=cat&modestbranding=1&rel=0';
     iframe.width = 560;
     iframe.height = 315;
     iframe.frameborder = 0;
     iframe.allow = "accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture";
     iframe.toggleAttribute("allowfullscreen");
     $(this).replaceWith(iframe);
  });
}