title: CSS variable with fallback value of itself
body: <p>What I'm trying to achieve in javascript will look like this:</p>
  
  <pre><code>myVar = newVar || myVar;
  </code></pre>
  
  <p>In css I'm doing the following:</p>
  
  <pre><code>--my-var: var(--new-var, var(--my-var))
  </code></pre>
  
  <p>Seems like it does not work. Is it even possible to have an old value in fallback if new value is undefined? </p>