Dark Mode for the App Please!

As someone who just started using Socrates, particularly during evening hours, I've noticed that the current bright interface causes significant eye strain. Please consider adding a dark mode!

Business Case:

1. User Retention: Dark mode has become an expected feature across modern applications
2. Accessibility: Helps users with light sensitivity and reduces eye strain
3. Energy Efficiency: Can help reduce battery consumption on devices with OLED/AMOLED displays
4. Competitive Advantage: Many competing products already offer this feature

Technical Considerations:

1. Could be implemented as a simple toggle in the user settings
2. CSS variables could make the implementation relatively straightforward
3. Could align with system preferences for automatic switching