Create one production-ready image asset for the StoryVault mobile app.
Persona: Captain Nova (space_adventure_captain).
Asset name: persona_full_nova.
Asset label for prompt context only: Captain Nova full body.
Step: global.
Usage: wizard_character_full.
Target size/aspect intent: 1024x1024.

Image description:
A cheerful childlike astronaut guide floating gently, round helmet, bright eyes, star headphones, white spacesuit with blue and gold accents, one hand welcoming the child.

Art direction:
- Style: premium children storybook, cinematic space adventure, soft 3D illustration, high contrast, cheerful, safe, magical
- Palette: deep navy, cosmic purple, electric blue, warm yellow, emerald green, coral red
- Lighting: soft glow, rim light, star sparkle highlights
- Character consistency: Captain Nova is a warm childlike astronaut guide with a round helmet, star headphones, blue-gold suit accents, and a friendly expression.
- Safety: No weapons, no frightening aliens, no realistic danger, no sharp horror elements.

Hard requirements:
- Do not include any readable text, letters, numbers, captions, logos, watermarks, labels, UI text, or signage inside the image.
- Create a polished rounded-square storybook choice tile. Use a clean dark navy or cosmic background inside the tile and keep the main subject centered with comfortable padding. Do not include a text label.
- Include Captain Nova only because this is a persona/avatar asset.
- Use a premium children storybook look with soft 3D forms.
- Use kid-safe, cheerful expressions and rounded shapes.
- Avoid horror, weapons, realistic danger, aggressive expressions, or adult themes.
- Output a single image asset, not a collage and not a phone UI mockup.