hey there. I think it would probably be easier if you would let AI code this element for you.
https://laytheme.com/tutorials/ai-mode.html
Here is the tutorial about how to connect your Claude or ChatGPT subscription (if you have one) to your Lay Theme.
And then you can just tell it to create a custom element where you can enter text, click on "Read More", and then you can describe to it how exactly you want the element to behave.
Because, honestly, I think your idea is really good. I just didn't really get requests like that too often before. I have to work on quite a lot of other things right now, and I'm not sure if I would code this element for you. I'm not sure if people would actually use it a lot, but with the AI, you can make it so you get the exact thing you want.