There is no hard and fast rule when it comes to whether cabinets should be lighter or darker than countertops. Ultimately, the decision will depend on your personal preference, the style and color scheme of your kitchen, and the overall aesthetic you are trying to achieve.
That being said, there are some general guidelines that can help you make a decision. If you want to create a bright and airy look, you may want to opt for lighter cabinets and countertops. Lighter colors tend to make a space feel more open and spacious, and they can help reflect light around the room.
On the other hand, if you want to create a more dramatic and bold look, you may want to consider darker cabinets and countertops. Darker colors can add depth and richness to a space, and they can create a sense of warmth and coziness.
Ultimately, the choice between lighter or darker cabinets and countertops will come down to your personal taste and the style of your kitchen. It's always a good idea to gather inspiration from interior design magazines, websites, and social media platforms to help you visualize what you want your kitchen to look like. You may also want to consult with a professional interior designer or kitchen remodeler for expert advice and guidance.