ef-fit-scale

Scales content to fit its container while preserving aspect ratio.

Observes its container and its first visible child. Applies a translate + scale transform to the child so it fills the container while maintaining aspect ratio — letterboxing or pillarboxing as needed. No shadow DOM: the child element is transformed in place.

<ef-fit-scale style="width: 100%; height: 400px;">
  <ef-timegroup mode="fixed" duration="5s" class="w-[1920px] h-[1080px]">
    <!-- composition content -->
  </ef-timegroup>
</ef-fit-scale>