Suggestion： Add a back to top button

### Expected behavior

Describe what you expected to happen.
Add a back to top button
### Actual behavior

Describe what actually happened, being specific about how this differs from your expectations.

### Steps to reproduce the behavior

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### System information

- **Operating system**:
- **Operating system version**:
- **Browser**:
- **Browser version**:
- **Enabled Browser Extensions**:

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