fix serve recipe: filter output to Development Server start + [200] requests only

refactor: unify CSS color variables across public and admin

- Replace old variable structure with new standardized naming:
  - Background: --bg-primary, --bg-secondary, --bg-tertiary, --bg-active
  - Text: --text-primary, --text-secondary, --text-tertiary
  - Border: --border-primary, --border-secondary
  - Status: --success, --error, --warning
  - Accent: --accent-primary, --accent-secondary, --accent-foreground, --accent-muted
- Remove admin-specific color variables (--admin-*)
- Update all CSS files to use shared variables:
  - variables.css, common.css, main.css, admin.css
  - tfe.css, search.css, apropos.css, system.css, colors.css

public/assets/css/README.md

@@ -0,0 +1,35 @@
+# CSS Architecture
+
+## File Structure
+
+- **variables.css** - CSS custom properties (variables) for colors and theme values
+- **colors.css** - Reference documentation of all color values used in the project
+- **common.css** - Shared styles: reset, header/nav, search bar, accessibility utilities
+- **main.css** - Home page styles
+- **admin.css** - Admin section styles
+- **system.css** - System page styles
+- **search.css** - Search/Directory page styles
+- **apropos.css** - About page styles
+- **tfe.css** - Individual thesis page styles
+- **easymde.min.css** - EasyMDE editor styles (minified, third-party)
+- **modern-normalize.min.css** - Modern normalize reset (minified, third-party)
+
+## Imports
+
+All CSS files automatically import `variables.css` to access CSS custom properties.
+
+## Variables
+
+### Shared Variables (public pages)
+- `--purple`, `--purple-dark`, `--purple-light` - Purple palette
+- `--black`, `--white` - Base colors
+- `--grey-light` - Light grey background
+- `--border-color` - Border color
+- `--text-muted` - Muted text color
+
+### Admin Variables
+- `--admin-bg`, `--admin-bg-alt` - Background colors
+- `--admin-border` - Border color
+- `--admin-text`, `--admin-text-muted` - Text colors
+- `--admin-purple` - Accent color
+- `--admin-input-bg` - Input background