title: Changing background color input when contain word
body: <p>Hi I have code like below, when I put word "BH" or "bh" my background color will change on yellow. How change javascript code to detect contain word in long text? 
  For example, when I put text like "Somethink text BH in input" background not change on yellow I would like to detect single letters like BH in long text</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 checkFilled() {
   var inputVal = document.getElementById("subEmail");
      if (inputVal.value == "BH" || inputVal.value == "bh") {
          inputVal.style.backgroundColor = "yellow";
      }
      else{
          inputVal.style.backgroundColor = "";
      }
  }
   
  checkFilled();</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;input type="text" id="subEmail" onchange="checkFilled();"/&gt;</code></pre>
  </div>
  </div>
  </p>