title: Check if mouse is inside div
body: <p>I want to use an if statement to check if the mouse is inside a certain div, something like this:</p>
  
  <pre><code>if ( mouse is inside #element ) {
   // do something
  } else {
   return;
  }
  </code></pre>
  
  <p>This will result in the function to start when the mouse is inside #element, and stops when the mouse is outside #element.</p>