Prompt for a cover illustration for your blog post

Act as an editorial art director and an expert in prompts for image generators.

From my blog post's topic and my brand palette, write me a prompt in English to generate a conceptual illustration to go with the post, coherent with my brand.

Post topic: [E.G. how to automate your business with AI without knowing how to code]
Visual idea or metaphor I have in mind (if any): [E.G. a person building something out of floating pieces, or leave it blank]
My brand palette: [E.G. magenta and purple on a dark background, high contrast]
Visual style I prefer: [E.G. flat digital illustration, soft 3D, minimal line art]

Give me:
1. A detailed main prompt in English: composition, subject or visual metaphor, style, color palette, lighting and mood.
2. The recommended aspect ratio for a blog cover (16:9 or 4:3) and why.
3. An alternate style variation, in case the first one doesn't fit the post.
4. A short tip for keeping visual consistency across covers for different posts.

Rules: don't invent elements, text or logos I didn't ask for; use only the palette and style I gave you. If a detail is missing for a recommendation, mark it as [detail to verify] instead of assuming it.