Change opacity of horizontal Scroll for Detailed Results

[GERey]

Bug Description

Bug description

Please describe.

The opacity of the scroll bar is clear, and so text overlaps with each other when you horizontally scroll. Not the end of the world but looks a bit messy when scrolling.

If you are on PostHog Cloud it would be really valuable if you can share any links where the problem occurs. This speeds up our ability to troubleshoot tremendously. https://us.posthog.com/project/69688/insights/YpWitPOz

How to reproduce

1. Resize windows so that you have a horizontal scroll bar
2. Scroll until text overlaps

Additional context

Maybe just changing the opacity of the first column would do the trick?

Debug info

- [x] PostHog Cloud, Debug information: [please copy/paste from https://us.posthog.com/settings/project-details#variables]
- [ ] PostHog Hobby self-hosted with `docker compose`, version/commit: [please provide]
- [ ] PostHog self-hosted with Kubernetes (deprecated, see [`Sunsetting Kubernetes support`](https://posthog.com/blog/sunsetting-helm-support-posthog)), version/commit: [please provide]