You are helping me create project guidelines for Lovable development. These guidelines will keep my AI assistant focused and prevent feature creep.

My project: [Insert your Week 3 validated idea]

Core user journey: [The main thing users do in your app]

Target completion: [One sentence describing success - "Users can input X and get Y back"]

Create concise project guidelines that I can paste into Lovable's Knowledge section. The guidelines should:

1. State the core purpose and what success looks like
2. Specify what NOT to build (no user accounts, payments, analytics, etc. until core works)
3. Define the design aesthetic (clean, simple, focused on functionality)
4. Set rules about staying focused on the core user journey
5. Emphasise building one feature at a time

Keep it under 200 words. Format as clear, actionable guidelines that an AI can follow consistently.