[Bug] UI theme toggle renders poorly in Light/Auto mode

[ME-Massine]

Description

When switching the theme from Dark to Light or Auto on the Svelte Cloudinary docs site, the UI layout and color contrast look inconsistent. Some text and background elements lose readability, especially in the header and cards.

Steps to Reproduce

1. Go to https://svelte.cloudinary.dev/
2. Use the theme switcher in the top-right corner.
3. Change from Dark to Light or Auto.

Expected Behavior

Colors and layout should adapt cleanly between themes, maintaining consistent readability and contrast.

Actual Behavior

The Light and Auto modes show poor contrast and visual imbalance compared to Dark mode.

Screenshots

Environment

Browser: Firefox Device: Desktop