title: Change CSS style in a specific class conditionally in angular+2
body: <p>let's assume that I have a class</p>
  <pre><code>.some-class{
     /// some style ex:
     display: none
  }
  </code></pre>
  <p>I want to target that specific class to change the style to</p>
  <pre><code>.some-class{
     display: block
  }
  </code></pre>
  <p>based on some user action in my application
  so it be something like this</p>
  <pre><code>&lt;div [class.some-class]=&quot;condition? display: block&quot; &gt;
  
  &lt;/div&gt;
  </code></pre>
  <p>is that possible without the need of using JavaScript DOM?</p>