How do disable visual touch feedback on buttons

Like the title says, I’d like to disable the visual touch feedback on buttons in my (Sveltekit) Capacitor app. On my iPhone is looks like a short darkened overlay on the button after the touch event ends. On Android there is a similar but slightly different effect. How can I modify/disable this? It does not seem to be a css option as :focus and :active does not effect it.

Solved: it’s a webkit thing (…of course). Use -webkit-tap-highlight-color: transparent on elements you want to disable the visual feedback on.