UI: Improve contrast ratio between focus / hover

[chocoscoding]

hover and focus states to meet the minimum requirement of 3:1

Closes #24162

What I did

Adjusted the contrast ratio for focus and hover on and to pass 3:1 minimum contrast ratio requirements

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[cdedreuille]

Thanks a lot for your changes. I checked the branch locally and the result doesn't seem to work properly. When I hover a story the text is becoming white because you set the hover to use color: theme.color.lighter.
What was your intent by doing that?

[chocoscoding]

Oh, Pardon me. I didn't test for the light mode to see this.
In dark mode, the color of the text on hover and focus was lighter. Which made it pop and more noticable.
Which gave a good contrast ratio score as well.

However, it wasn't so complete.

I have removed them and changed the hover color

[cdedreuille]

Same here. Why did you choose to set it to use color.lighter ? These colors are set and would be the same if you are using dark and light mode.

[chocoscoding]

I would love to get your opinion on this though,
If i was to archive the text popping on focus and hover effect on both light mode and dark mode.

I did color: theme.base === 'light' ? theme.color.darkest : theme.color.lighter and it works well.

Do you think its too much or you would like to see it

[cdedreuille]

Yes the code you shared depending on the them could work. We are working on a new way to set colours in Storybook that will make working with light and dark mode much easier. But for now this solution could work well.

[chocoscoding]

Oh, noted.
Would love to see how you handle the theme.
Also I have made the contrast ratio good without any highlighting of the color attribute

Or use the proposed method

[cdedreuille]

Even better. Then I think it's ok to be merged. Thanks a lot @chocoscoding for your help in making Storybook more accessible. 🙏