title: Transitioning multiple child elements with one <transition> wrapper
body: <p>I want to set multiple transitions (on separate child elements) inside one parent <code>v-if</code> state change.</p>
  
  <p>For example when I display a modal I want the background blur to <code>fadeIn</code> (using opacity) and the modal content to <code>slideIn</code> (using transition or animation). My current situation is the following, when I use the transition the background blur element (<code>.modal</code>) is transitioning along with the content (<code>.modal__content</code>):</p>
  
  <pre><code>&lt;transition enter-active-class="animated slideInRight" leave-active-class="animated slideOutRight"&gt;
    &lt;div class="modal" v-if="isVisible"&gt;
      &lt;div class="modal__content"&gt;
        &lt;/slot&gt;&lt;slot/&gt;
      &lt;/div&gt;
    &lt;/div&gt;
  &lt;/transition&gt;
  </code></pre>