title: How to use calc function in less
body: <p>I want to use calc function in less. My required output should be <code>right: calc(-100vw + 400px);</code>. Therefore I used below code in less.</p>
  <pre><code>right: calc(~'-100vw + 400px');
  </code></pre>
  <p>But that code is not working. Can anybody help me with this?</p>
  <p>Thanks in advance</p>