fix: center TrackTools at bottom across all devices

[sreecharan-desu]

Center TrackTools at Bottom on All Devices

Summary

This PR ensures the TrackTools component is horizontally centered and fixed at the bottom of the viewport across all screen sizes using Tailwind CSS utilities.

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Changes Made

• Replaced incorrect Tailwind classes (itemsc-center, mx-auto w-full)
• Applied fixed bottom-0 left-1/2 transform -translate-x-1/2 for proper centering
• Wrapped TrackTools in a flex container for consistent alignment

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Before

TrackTools alignment was inconsistent (not centered) on various devices.

After

TrackTools is now perfectly centered and fixed at the bottom of the screen across all viewports.

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Code Snippet

<div className="fixed bottom-0 left-1/2 transform -translate-x-1/2 flex items-center justify-center">
  <TrackTools allProblems={track.problems} track={track} problemIndex={problemIndex} />
</div>

Why This Matters

This fix improves layout consistency and enhances user experience across mobile and desktop devices.

Thank you for reviewing