Fix recurring faded "Skills Leaderboard" heading and subtitle

[Muskankr]

The page heading and subtitle render at very low opacity/contrast against the background. This is a new page, which suggests the root-cause token fix either hasn't shipped or wasn't applied here. Acceptance criteria:

Heading and subtitle meet WCAG AA contrast

Verified in both light and dark mode

[SohammPawarr]

Hi @Muskankr, I'd love to fix this accessibility contrast issue—could you please assign it to me?
I will update the heading and subtitle CSS to use the correct semantic design tokens instead of low-opacity values.
I'll ensure the applied text colors meet WCAG AA standards by ensuring proper contrast against the page background.
By utilizing the project's existing theme variables, the fix will automatically support both light and dark modes.
Finally, I'll test the changes locally using a contrast checker to verify accessibility compliance before opening the PR.