[Visual Request] Suggestions for improving default slider styling in dash=4.0.0

Hi!

First off, thank you for the great work on the redesigned Dash components - they look great overall! 🥳

While using the updated sliders, I noticed a few small visual details that might be worth reconsidering in the default styling. None of these are major issues, and we've been able to address them with custom CSS on our end, but I wanted to share the feedback in case it's helpful :)

• Here is the example app with the environment: https://py.cafe/huong-li-nguyen/dash-slider
• Using dash=4.0.0

1. Slider track and dot opacity

The current opacity applied to the slider track and dots makes them feel slightly visually disconnected. Removing the opacity (or assigning a different color) might help the elements feel more cohesive as a single component.

In our case, we worked around this by overriding the Dash CSS variable with a different color. However, it might be worth considering whether the default styling could achieve this more naturally.

2. Dot alignment

The slider dots don’t appear to be perfectly center-aligned with the track when using dots=True- they look slightly offset on close inspection (see screenshot). We corrected this with custom CSS, but it may be worth adjusting in the default styles to ensure precise alignment.

3. Start and end dot positioning

This one is more subjective, but it might look cleaner if the first and last dots were positioned exactly at the start and end of the track, rather than slightly inset.

Here the start and end point are positioned right at the edge of the track:

Currently the start/end dot are positioned slightly inset:

Would any of these adjustments be feasible in the default styling?

Thanks again for all your work on this - we really appreciate the improvements! 🫶

Best,
Li