MKdocs Typography, formatting and color improvements

[allisonwhilden]

Why are these changes needed?

Cleaning up MKDocs styling as per #1530. This doesn't address everything, but below are details of what it fixes.

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Improves styling and information hierarchy for all the headers

I updated the styling for H1 - H5. I kept Jersey10 just for limited usage of H1, but made sure it wasn't uppercase. I switched all headers to be full black instead of grey, adjusted the spacing of all of them, and made H2-H5 Jetbrains Mono.

ex. Before/After

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Improves the colors for dark mode

I tweaked the colors for dark mode to increase the contrast and just look a little more polished.

ex. Before/After

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Cleans up formatting bugs in the user guide section

There were a number of formatting bugs I found while looking through all of the pages of the user guide section. These included:

Lack of space around a list making it so the list didn't display like a list

A H1 used inadvertently elsewhere on the page making it so MKDocs didn't auto-generate an H1 at the top from the front matter

A code block that had a code block in it as an output example from an agent which would cause an early end to the code block. I wrapped those code blocks in 4 ticks (````)

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Simplified the layout of the key features on the home page

The centered text of that length is just really ragged and hard to read. Switched to a vertical stack instead of a horizontal layout. The entire home page will be redesigned soon, but this felt like a nice short-term clean-up

Before/after (please note -- the yellow background at the top wasn't removed. I think there was an error with my local server with accessing some of the assets that I haven't solved yet.)

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Related issue number

#1530 (but doesn't close it fully)

Checks

• I've included any doc changes needed for https://docs.ag2.ai/. See https://docs.ag2.ai/docs/contributor-guide/documentation to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

[CLAassistant]

All committers have signed the CLA.

[allisonwhilden]

@harishmohanraj I didn't fully remove Jersey10. Instead, I turned off the uppercase text transform, darkened the color and increased the font size, and reduced it to only being used on H1. I used Jetbrains Mono on H2-H6. I think this combo reads nicely, while remaining true to our style and brand. Let me know what you think. Thanks!

[allisonwhilden]

@harishmohanraj @qingyun-wu I have fixed all the checks and added more details above about my changes. Review when you get a chance and let me know what you think and if we can get this ready to merge. Thanks!

[davorrunje]

Looks great!

[harishmohanraj]

Hi @allisonwhilden, The font combination looks really good on the website. I have made a couple of minor css changes to your PR.

• Reduced the h1 font size from 3 rem to 2 rem. It looked way too large.
• Fixed a small css issue in use stories page.