Convert HTML to reST with sphinx-design

[QuLogic]

Using sphinx-design's grid, tabs, and cards, we can replicate most of our brochure site using reST instead of HTML. This allows us to drop a lot of custom CSS, some JavaScript, and most importantly, allows wiring up the build for translations.

This is not a perfect translation, perhaps 90% of the way there. Notable differences are:

1. I didn't keep the tweak to the document the full width with smaller max-width containers. That makes us use the default, which is a bit narrower, but probably not enough to matter. The other major difference is that the coloured rules are only the width of the content, instead of the full page. I don't think that there's any way to make them overflow easily.
2. The containers in sphinx-design cannot have any reST headings, so the HTML doesn't have headings, only div that are styled like them; this is a bit annoying from a semantic point of view, and possibly broken for accessibility. I'm not sure if this is something sphinx-design can fix or if it's inherent to reST.
3. While I was mostly able to replicate the gradient on the tab colours, I wasn't able to replicate the tab labels being on the side. I'm not too sure if this is possible in pure CSS with the HTML structure that sphinx-design generates, but maybe it's something that could be implemented on their side.
4. The footer remains specified in HTML, but I wonder if we want to tweak its style a bit since it remains full-width while everything else isn't (including the header, which comes from pydata-sphinx-theme).

Along those lines, I had some ideas of possible tweaks:

1. News items could be placed in cards for a slightly different styling. The cards could be fully clickable as well, though that would preclude internal links like the one that is in the GSoC news entry.
2. Instead of tabs, the tool examples could be a card carousel