Splendid astro

Not

Not is the opposite of If. It lets you render content based on the inverse of a condition.

Not is the opposite of If

Not renders the default slot when the condition is falsey, and the else slot when the condition is truthy.

index.astro
<Not condition={true}>
  <div><!-- renders when falsey --></div>
  <div slot="else"><!-- renders when truthy --></div>
</Not>