Prompt pattern
Minimalist visual style
A reusable phrase that asks for a clean, uncluttered look.
Fills the style part of a prompt.
Use a minimalist visual style. Plenty of white space, a single accent colour, no decorative graphics, and no more than two typefaces.
Drop this straight into a longer prompt. It works because it names the constraints, "one accent colour", "two typefaces", instead of using the word clean and hoping the agent agrees with your definition of it.