Mobile Site Display Differences: SoundWave vs. Bubble Beehives

Hope this is the correct place to post: Why is there this difference on mobile devices between these two beehive sites: https://thesoundwave.live/ and https://arlbubble-newsletter.beehiiv.com/? How do I make my site (The SoundWave) look like the Bubble: specifically, (1) posts of the Bubble don't require zooming in, while it does on the SoundWave; and (2) I would like the archive to look like the Bubble's (single column vs. double column on mobile).