Update the design to only use new classes and remove old classess

[stackingsaunter]

Part of #2541, depends on #2542

Tasks

• [ ] Update all design to only use new color classes: Light mode, Dark mode
• [ ] Remove color old classes

Notes

• I will update this issue with some more detailed handoff of critical components of the design when #2541 closes

• I suggest using newly introduced dev mode in Figma for better viewing the file, you can trigger it clicking on a toggle in the top right corner:

[wareeshaali2003]

@stackingsaunter can you guide me about this issue in detail