title: How to unfold only a child element of its parents own in Class Syntax?
body: <p>I'm trying to select a child element of its parent own (a.k.a <code>firstPanel</code>) in Class Syntax but have no idea how would I do this.</p>
  
  <p>It's easy to refer the each <code>firstPanel</code> in the normal function, and it works perfectly fine like this: </p>
  
  <pre><code>$(function accordian() {
    $('.mobileCategory').on('click', function() {
      if (!$(this).hasClass('open')) {
        $(this).addClass('open');
        $(this).siblings('.firstPanel').stop(true, true).animate({
          maxHeight: 1000 + 'px'
        });
      } else if ($(this).hasClass('open')) {
        $(this).removeClass('open');
        $(this).siblings('.firstPanel').stop(true, true).animate({
          maxHeight: null
        });
      }
    })
  })
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/xnQsl.gif" alt="enter image description here"></p>
  
  <p>but when I click the element under the Class Syntax, the whole <code>.firstPanel</code> is going to unfold like this:</p>
  
  <p><img src="https://i.stack.imgur.com/dRrTn.gif" alt="enter image description here"> </p>
  
  <p>I know <code>this.list</code> is assuming the entire <code>firstPanel</code>. I just don't know how would I refer the child element of the parents own in the Class Syntax.</p>
  
  <p>Are there any ways to do this?</p>
  
  <p>Full Code:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>class Accordian {
    constructor($el) {
      this.$el = $el;
      this.category = this.$el.find('.mobileCategory');
      this.list = this.category.siblings();
      /* Boolean Flags */
      this.flags = {
        active: false,
      };
    }
    clicked(e) {
      console.log('text')
      this.list.css({
        maxHeight: 1000 + 'px'
      })
    }
    manange() {
      console.log(this.list, 'text');
      this.$el.on({['click']: (e) =&gt; this.clicked(e)});
    }
  }
  var thatAccordian = new Accordian($('#mobile-menu'));
      thatAccordian.manange();</code></pre>
  <pre class="snippet-code-css lang-css prettyprint-override"><code>a {
    text-decoration: none;
    color: white;
  }
  #mobile-menu {
    position: absolute;
    z-index: 999;
    color: white;
    width: 100%;
    height: calc(100% - 110px);
    top: 110px;
    background-color: #202020;
  }
  .wrapper, li {
    display: block;
    flex-flow: column;
    margin: 1rem;
    transition: all 500ms cubic-bezier(0.455, 0.03, 0.515, 0.955);
  }
  .wrapper &gt; li &gt; ul {
    transition: all 500ms cubic-bezier(0.455, 0.03, 0.515, 0.955);
    display: block;
    flex-flow: column;
    max-height: 0;
    overflow: hidden;
    margin: 0 1rem;
  }
  .wrapper &gt; li &gt; ul &gt; li {
    transition: all 500ms cubic-bezier(0.455, 0.03, 0.515, 0.955);
    display: block;
    flex-flow: column;
    margin: 1rem 0;
    font-size: .8rem;
    outline-width: 0;
    border-width: 0;
    border-bottom: 1px solid white;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>  &lt;div id="mobile-menu"&gt;
      &lt;ul class="wrapper"&gt;
        &lt;li&gt;
          &lt;a href="#" class="mobileCategory"&gt;MODELS&lt;/a&gt;
          &lt;ul class="firstPanel"&gt;
            &lt;li&gt;URUS&lt;/li&gt;
            &lt;li&gt;HURACÁN&lt;/li&gt;
            &lt;li&gt;AVENTADOR&lt;/li&gt;
            &lt;li&gt;FEW OFF&lt;/li&gt;
            &lt;li&gt;CONCEPT&lt;/li&gt;
            &lt;li&gt;AD PERSONAM&lt;/li&gt;
            &lt;li&gt;OVERVIEW&lt;/li&gt;
          &lt;/ul&gt;
        &lt;/li&gt;
        &lt;li&gt;
          &lt;a href="#" class="mobileCategory"&gt;BRAND&lt;/a&gt;
          &lt;ul class="firstPanel"&gt;
            &lt;li&gt;PEOPLE&lt;/li&gt;
            &lt;li&gt;HISTORY&lt;/li&gt;
            &lt;li&gt;MASTERPIECE&lt;/li&gt;
            &lt;li&gt;DESIGN&lt;/li&gt;
            &lt;li&gt;INNOVATION &amp; EXCELLENCE&lt;/li&gt;
            &lt;li&gt;OVERVIEW&lt;/li&gt;
          &lt;/ul&gt;
        &lt;/li&gt;
        &lt;li&gt;
        &lt;li&gt;&lt;a href="#" class="mobileCategory"&gt;MOTORSPORT&lt;/a&gt;&lt;/li&gt;
        &lt;li&gt;&lt;a href="#" class="mobileCategory"&gt;STORE&lt;/a&gt;&lt;/li&gt;
      &lt;/ul&gt;
    &lt;/div&gt;
    &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"&gt;&lt;/script&gt;</code></pre>
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  </p>