Generate a minimalist stock photo featuring a dog's birthday celebration. Focus on simplicity and elegance in the composition. The image should include a dog wearing a birthday hat, sitting beside a small, decorated birthday cake. Emphasize clean lines and an uncluttered background to evoke a sense of joy and celebration. Consider using soft lighting to highlight the scene. Aim to create a visually appealing yet minimalist image that captures the essence of a pet's special day, suitable for commercial use in stock photography.