[BUG] - Light/dark mode selector overrides user setting to revert to default

[hey-august]

Describe the bug
When set to light mode, the docs site regularly reverts to the default dark mode on a roughly daily cadence.

To Reproduce
Steps to reproduce the behavior:

1. set light mode
2. wait
3. observe
4. See error

Expected behavior
If a user sets light mode, that setting should persist indefinitely.