FIx DocNavbar and DocsBanner in light mode

<img width="1830" height="319" alt="Image" src="https://github.com/user-attachments/assets/83386df5-ac75-43c0-ade6-733e843796f6" />
<img width="1844" height="108" alt="Image" src="https://github.com/user-attachments/assets/f0e5d3fb-b1c9-440f-83c0-cdcef84f6602" />

fix light theme properly in both