Radio circles are sometimes misaligned/not centred

[tom-clarke-dluhc]

Description of the issue

When using the radio component the concentric circles for a selected option are sometimes not centred for specific browser/zoom percentages.

Steps to reproduce the issue

On the frontend example, while using Edge browser and a zoom of 90% the middle circle is quite a way from the middle. This can also be seen for 80% and some other common zoom percentages.

Actual vs expected behaviour

I would expect the circles to always be centred but they aren't for some zooms.

Environment (where applicable)

• Operating system: Windows 10
• Browser: Edge
• Browser version: 126
• GOV.UK Frontend Version: most recent

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[tom-clarke-dluhc]

@kateriley1

[querkmachine]

This is caused by how browsers round fractional values to full pixels at certain zoom levels. There's a fuller explanation in the backlog issue here: alphagov/govuk-design-system-backlog#59 (comment)

[tom-clarke-dluhc]

Thanks for the reply. Good to know that there's not much that can be done to resolve