The TOC toggle button was appearing near the end of posts instead of
floating at a fixed position. This happened because the button was
rendered inside the PostLayout component hierarchy.
Changes:
- Use React Portal to render TOC button at document.body level
- Add mounted state for proper SSR/client hydration
- Button now floats like back-to-top button, visible from start
This ensures the button is always visible and accessible, similar to
the back-to-top button behavior.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
gbanyan
a77cd17419