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## Summary by CodeRabbit
- **New Features**
- Upgraded the theme customization interface with a dropdown that lets
you choose from multiple themes (Light, Dark, Azure, Gray). Users can
now adjust options like text colors, background color, gradients, and
banner display more intuitively.
- Introduced a structured approach to theme variables, enhancing
compatibility and customization options.
- **Style**
- Enhanced the header’s visual presentation by introducing dynamic
background imagery and refined layout adjustments for a more polished
look.
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