Design a harmonica with the following features: 1. **Materials**: Use a matte black finish for the body instead of shiny metal. 2. **Case**: Replace the traditional red interior with a deep blue velvet lining. 3. **Shape**: Alter the harmonica shape to have rounded edges for a more ergonomic grip. 4. **Color**: Change the main color of the harmonica to a dark charcoal gray. 5. **Text**: Replace any brand references with a simple, elegant logo at the center. 6. **Details**: Add gold accents around the edges for a premium look. Ensure it looks modern and appealing while maintaining functionality.