Fixes Issue🛠️

Closes #204

Description👨‍💻

This PR includes several improvements and fixes:

1. Updated Styling:

   • Improved overall styling for a more polished and consistent look across the app.
   • Enhanced responsiveness for better user experience across different screen sizes.

2. Fixed DataGrid Element:

   • Corrected issues related to the DataGrid element, ensuring proper alignment, data rendering, and interaction functionality.

3. Fixed Availability Logic for Dates:

   • The previous code was not updating unavailable dates based on the current date. Now, the availability of time slots is checked and updated daily, reflecting the correct status of each time slot for the current day.
   • Time slots that are selected once now remain unavailable only for the current day, preventing them from being marked unavailable for all days.

Type of Change📄

• Bug fix (non-breaking change which fixes a bug)
• Style (non-breaking change which improves website style or formatting)
• Responsiveness (non-breaking change which improves UI/UX on different screen sizes)

Checklist✅

• I am an Open Source contributor
• I have performed a self-review of my code
• My code follows the style guidelines of this project
• I have commented on my code, particularly in hard-to-understand areas

Screenshots/GIF📷