title: Bulma: make links bold, wait 1000 ms, then make them un-bold
body: <p>Using vanilla javascript and <code>bulma.css</code>, how can I unhide a span, make all the links in the span  bold, then after a given amount of time (say, <code>1000 ms</code>), take away the bold font weight. The first part, unhiding and making the links bold works fine using the following code:</p>
  <pre class="lang-js prettyprint-override"><code>function unhide_bold_unbold() {
      mode_sents = document.getElementsByClassName('kanji-sent')
      for (let i = 0; i &lt; mode_sents.length; i++) {
          mode_sents[i].classList.remove('is-hidden')
          // Bold all links
          links = mode_sents[i].getElementsByTagName('a')
          for (let j = 0; j &lt; links.length; j++) {
              links[j].classList.add('has-text-weight-bold')
          }
      }
  }
  </code></pre>
  <p>I tried adding the following at the end of the function, but it just delays the unhiding by 1000 ms, and the links never look bold.</p>
  <pre class="lang-js prettyprint-override"><code>    sleep(wait_ms)
      for (let i = 0; i &lt; mode_sents.length; i++) {
          links = mode_sents[i].getElementsByTagName('a')
          for (let j = 0; j &lt; links.length; j++) {
              links[j].classList.remove('has-text-weight-bold')
          }
      }
  </code></pre>
  <p>...which uses the following function:</p>
  <pre class="lang-js prettyprint-override"><code>
  
  function sleep(milliseconds) {
    const date = Date.now();
    let currentDate = null;
    do {
      currentDate = Date.now();
    } while (currentDate - date &lt; milliseconds);
  }
  </code></pre>
  <p>How can I make <code>bulma</code>'s class update the font weight, then wait, then remove the bold font weight?</p>
  <pre class="lang-html prettyprint-override"><code>&lt;span class=&quot;kanji-sent is-hidden&quot;&gt;&lt;a onclick=&quot;show_kanji_data('彼')&quot;&gt;彼&lt;/a&gt;等は皆、この&lt;a onclick=&quot;show_kanji_data('曇')&quot;&gt;曇&lt;/a&gt;天に押しすくめられたかと思う程、揃って背が低かった。&lt;/span&gt;
  </code></pre>