Feature Request: Adjustable Theme Brightness / Medium Theme Option #87

The current theme implementation offers only two extremes: dark mode is too dark and light mode is too bright. This makes extended use uncomfortable for many users and doesn't accommodate different lighting conditions or personal preferences.

Current Behavior:

Dark mode: Very dark, potentially causing eye strain in moderate lighting
Light mode: Very bright, potentially causing glare and discomfort

Request:

Implement one or more of the following options:

1. Medium/Gray Theme: Add a third theme option that provides balanced contrast (similar to how it was in v3)

   • A softer dark theme (dark gray backgrounds instead of pure black)
   • A dimmed light theme (off-white/cream backgrounds instead of pure white)

2. Brightness Slider: Add a brightness adjustment control within each theme

   • Allow users to fine-tune the background/foreground contrast
   • Persist user preference in local storage or user settings

Benefits:

• Reduced eye strain during extended use
• Better accessibility for users with light sensitivity
• Improved user experience across different lighting conditions

Thank you.