various homepage improvements (#3387)

## Description:

Various changes, applied more styling from the homewrecker branch

* dimmed background
* Content width: expands to 24cm on 2xl screens
* game card ocean color: French blue → sky-950
* Action buttons (Create/Ranked/Join): French blue → slate-700
* Modifier badges: teal → sky blue, to keep in color scheme
* CTA buttons (Start Game, Join Lobby): blue-600 → sky-600 across all
modals and <o-button>
* Nav font: font-bold tracking-widest → font-medium tracking-wider
* Username/flag inputs: font weight lightened to font-medium
tracking-wider
* Language flag: blue color filter applied


BEFORE:


<img width="1446" height="978" alt="Screenshot 2026-03-08 at 6 48 57 PM"
src="https://github.com/user-attachments/assets/ff748e1c-6cb5-4a66-ac27-9538e935b325"
/>

AFTER:

<img width="1629" height="988" alt="Screenshot 2026-03-08 at 6 46 53 PM"
src="https://github.com/user-attachments/assets/364bb57a-65ff-40cf-931b-067ed36e3c5b"
/>


## Please complete the following:


- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

evan

src/client/components/baseComponents/Button.ts

@@ -14,7 +14,7 @@ export class OButton extends LitElement {
   @property({ type: Boolean }) fill = false;
   @property({ type: Boolean }) submit = false;
   private static readonly BASE_CLASS =
-    "bg-blue-600 hover:bg-blue-700 text-white font-bold uppercase tracking-wider px-4 py-3 rounded-xl transition-all duration-300 transform hover:-translate-y-px outline-none border border-transparent text-center text-base lg:text-lg whitespace-normal break-words leading-tight overflow-hidden relative";
+    "bg-sky-600 hover:bg-sky-700 text-white font-bold uppercase tracking-wider px-4 py-3 rounded-xl transition-all duration-300 transform hover:-translate-y-px outline-none border border-transparent text-center text-base lg:text-lg whitespace-normal break-words leading-tight overflow-hidden relative";
 
   createRenderRoot() {
     return this;