Some further mockuppery
1. Game logo. The words below the logo could change base on the title of the enabled mod.
2. Click a red button for the main category ("Structures" in this example). Some articles can be listed under multiple categories if they are relevant.
3. A Drop menu quickly slides down
4. And the category header slides out
5. Choosing an item from the Drop menu (3) changes the article's Graphic
6. And the text of the item shows here, complete with a scrollbar on the right. I've only shown the text for the Athenian Civic Center for illustrative purposes.
7. The articles can be cross referenced. We can add inline links to relevant articles (on click), or have tooltips (on hover). In this example, "Solon" is linked because it's the Athenian Catafalque (Relic). "Citizens" is linked to the article under "Civilians and Economics" category that tells about the concept of "Citizens" in the game. "Athens" links to the "Athenians" article under "Cultures and Civilizations." "Greek" links to the culture article. "Council" links to the "Council Chamber" structure article. "Democracy" links to the Athenian civ bonus article. And lastly, "ostracism" links to that technology's article.
8. Back button and a "Random Article" button, akin to Google's old "I'm feeling lucky" button.
5,6, and 7 could be blank until you choose an article from the drop menu (3), or there can be a generic article and graphic detailing what a "Structure" is.
Audio:
A cool idea I had would be to play the object's selection sound any time you clicked it from the drop menu. So, click the Civic Center article in the list, the Civic Center selection sound plays as the article loads.
Click a Technology article, the tech completion sound is played.
Click a Civilization's article, there can be either a short civ-specific intro sound, or in the article itself can have a little that plays music from the civ's json.