Coherent styling for sponsor logos

### ⚠ Related problems

The styling of our sponsor logos are incoherent. They could be integrated better into the website theme. Related to this is the food menu div, which content could be entirely shown but would push the sponsors down and I was thinking we could maybe have the sponsors directly under the image banner.

### 📝 Description

I want a proper darkmode and lightmode styling of them. Alternatively have them under the header banner.

### 💡 Additional context

_No response_