Vertical scrolling marquee

One of my websites uses a scrolling marquee for news announcements on the homepage. I've implemented this as a hand-coded HTML file that is displayed in an iFrame. The current code uses the <marquee> tag, but this is now depreciated, so, whilst it still works, I'd like to replace it with a JavaScript or CSS alternative, but I'm having problems finding a solution that works well.

The best CSS solution I've found is this one: https://codepen.io/strongpom/pen/qmooZe. However, I'm having several problems with this. First, I can't set it to be 100% high, and second, I can't set a consistent scroll speed: just a time for the whole loop to cycle. This means that if there's not much content, the scroll speed is slower than if there's a lot of content.

I've also experimented with this JavaScript version, which is more promising: https://www.jqueryscript.net/animati...arquee-js.html However, the problem I'm having with this is that I can't find a way to make the scrolling start from the bottom: when it loads, the content starts at the top and so you have to read the first few lines very quickly before they scroll out of view.

Can anyone help me? I think the JS one might be the best way to go, but I need to modify it to start scrolling from the bottom.

It should be possible to set jqMarquee to start outside of view. "startVisible" should be the option you are looking for. Try to set it to 0 or false.
Please ask again if it doesn't work. It is some time ago, but I also made experiments with it.
If your content is pictures only you could use a widget I posted in another thread some time ago. If you are interested just ask and I will try to find the thread.
If I remember correctly the current version of jqMarquee is buggy for vertical scrolling, but I'm not 100% sure about that. Would need some testing I guess. If you give some more information on what is included in the marquee I could try out a little bit.