title: How to target specific Element in ClassName loop and manipulate it (not all elements) in Javascript/Jquery?
body: <p>I'm having difficulties finding a solution for my problem. I have a collection of elements which have the same class name. They are all hidden and I have a button which should display the specific element. I can cycle trough all of the elements, but my code display ALL of them instead of only the one i clicked.</p>
  <p>So I have to specify the current element which I want to change, maybe with &quot;this&quot;?</p>
  <p>The usage of class names can be changed. Hope you can help me.</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>function checkDoublettesLAS() {
    var doublettes = document.getElementsByClassName('checkSuccess');
  
    for (var i = 0, n = doublettes.length; i &lt; n; i++) {
      $(doublettes[i]).css('display', 'block');
    }
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="check"&gt;
    &lt;span class="checkSuccess" hidden&gt;
      foodummy1
    &lt;/span&gt;
    &lt;button onClick="checkDoublettesLAS();return false;"&gt;
      Show Text
    &lt;/button&gt;
    &lt;span class="checkSuccess" hidden&gt;
      foodummy2
    &lt;/span&gt;
    &lt;button onClick="checkDoublettesLAS();return false;"&gt;
      Show Text
    &lt;/button&gt;
    &lt;span class="checkSuccess" hidden&gt;
      foodummy3
    &lt;/span&gt;
    &lt;button onClick="checkDoublettesLAS();return false;"&gt;
      Show Text
    &lt;/button&gt;
    &lt;span class="checkSuccess" hidden&gt;
      foodummy4
    &lt;/span&gt;
    &lt;button onClick="checkDoublettesLAS();return false;"&gt;
      Show Text
    &lt;/button&gt;
    &lt;span class="checkSuccess" hidden&gt;
      foodummy5
    &lt;/span&gt;
    &lt;button onClick="checkDoublettesLAS();return false;"&gt;
      Show Text
    &lt;/button&gt;
  &lt;/div&gt;
  
  &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"&gt;&lt;/script&gt;</code></pre>
  </div>
  </div>
  </p>