Avada theme not responsive for YouTube videos?

Hi, I have 2 websites using Avada, https://investbangkokproperty.com/ and https://www.daryllum.com/

Youtube videos are responsive on the first site but not the second. Please see the examples:

https://investbangkokproperty.com/video-blogs/

versus

https://www.daryllum.com/videos/

Any idea why?