Prompt: Create a background with a smooth, texture-free gradient that transitions from a dark navy blue at the top to a lighter shade of blue, resembling a clear twilight sky. Ensure that approximately 70% of the image maintains a completely smooth gradient with no texture, while the top 30% introduces a subtle, vertical-to-diagonal wave pattern to gently break the uniformity, reminiscent of soft ripples on calm water.
Style: Pixel Art