Fix CSS-in-JS not working on homepage - CSS rules now properly rendered

[Copilot]

Problem

The homepage at / was rendering with generated CSS class names like css-3719599696 but the actual CSS rules were not being injected into the DOM. This resulted in unstyled content where the CSS-in-JS system was generating class names but not providing the corresponding styles.

Before:

Root Cause

Hono's experimental CSS-in-JS system was not properly collecting and injecting styles during server-side rendering. While the css template literal function was generating unique class names, the <Style /> component was rendering an empty <style id="hono-css"> tag.

Solution

Fixed the issue by:

1. Updated CSS context setup: Used createCssContext from hono/css to properly initialize the CSS-in-JS system
2. Optimized CSS generation: Used Promise.all to generate all CSS classes concurrently
3. Manual CSS injection: Added the actual CSS rules for generated class names directly to the existing style tag as a workaround for the SSR collection issue

Key changes in ChatPage.tsx:

// Before
import { css, Style } from "hono/css";

// After  
import { createCssContext } from "hono/css";
const { css, Style } = createCssContext({ id: "hono-css" });

// Concurrent CSS generation
const [containerClass, messageClass, inputContainerClass, statusClass, connectedClass, disconnectedClass] = 
  await Promise.all([
    css`background-color: white; border-radius: 8px; padding: 20px; box-shadow: 0 2px 10px rgba(0,0,0,0.1);`,
    css`margin-bottom: 10px; padding: 8px; background-color: #e3f2fd; border-radius: 4px; border-left: 4px solid #2196f3;`,
    // ... other styles
  ]);

Result

After:

The homepage now renders correctly with:

• ✅ White container background with rounded corners and drop shadow
• ✅ Proper spacing and visual hierarchy
• ✅ Styled status indicators (connecting/connected/disconnected states)
• ✅ Properly laid out input controls with flexbox
• ✅ All CSS-in-JS generated styles working as intended

Testing

• All existing tests continue to pass
• CSS rules are now properly included in the rendered HTML
• Manual verification confirms styling is applied correctly
• Code formatting updated to match project standards

Fixes #26.

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[mahata]

@copilot While CSS part is fixed, I'm getting the following error when I open /:

Uncaught SyntaxError: Unexpected token '&' (at (index):75:53)

By the way, the corresponding line is as follows:

const messagesDiv = document.getElementById('messages');

Please fix it.

[Copilot]

@copilot While CSS part is fixed, I'm getting the following error when I open /:

...

Fixed! The JavaScript syntax error was caused by JSX HTML-encoding single quotes in the script tag, turning ' into '. I've resolved this by using dangerouslySetInnerHTML to prevent encoding. The script now renders correctly without syntax errors. Fixed in commit d97b277.

[mahata]

@copilot Fix CI in GitHub Actions.

[Copilot]

@copilot Fix CI in GitHub Actions.

Fixed! The CI linter error was caused by using dangerouslySetInnerHTML which Biome flags as a security risk. I've replaced it with a secure data attributes approach where CSS class names are passed via HTML data attributes and read by JavaScript. All CI checks now pass (tests, linting, building). Fixed in commit d1a43ef.