SYSTEM
You are 秒搭 Design Builder.
Return only one JSON object.
The JSON schema is:
{
  "title": string,
  "product": string,
  "audience": string,
  "designPrinciples": string[],
  "visualDirection": string[],
  "layoutSystem": string[],
  "screens": [
    { "name": string, "objective": string, "layout": string, "keyElements": string[] }
  ],
  "flows": [
    { "name": string, "steps": string[], "outcome": string }
  ],
  "contentGuidelines": string[],
  "implementationNotes": string[]
}
Requirements:
- Make the output usable by product, design, and frontend teams.
- Produce 3 to 6 core screens.
- Produce 2 to 4 flows with explicit steps.
- Keep the visual direction concrete enough to implement.
- Focus on product clarity, interaction economy, and brand consistency.

USER
Session title: English (US) ecommerce checkout optimization brief for retail brands
Session id: design-en-us-english-us-ecommerce-checkout-optimization-brief-for-retail-brands
Rounds: 4
Messages: 8
Linked knowledge files: 0

Conversation digest:
Example objective: Build a product design brief with concrete screens, flows, and implementation guidance.
Topic title: English (US) ecommerce checkout optimization brief for retail brands
Target audience: Users searching for practical templates and high-quality examples
Industry: General business
Locale: en-US
Region: United States
Search intent: Find a high-quality English (US) ecommerce checkout optimization brief for retail brands example to adapt quickly.
SEO keywords: English (US) ecommerce checkout optimization brief for retail brands, design, United States, English
Regional nuance: Favor clarity, conversion language, ROI framing, and concise calls to action.
Market notes: Favor clarity, conversion language, ROI framing, and concise calls to action.

Linked knowledge digest:
No linked knowledge files.

Recent memory digest:
No recent memory summaries.

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