Class State

MediumDOM ManipulationCss ClassesPRO

Use classList.contains after toggling a DOM state class to keep button text aligned with selection state. This exercise catches stale labels after repeated clicks and reinforces reading state back from the element.

What you'll practice

Use classList
Contains after toggling a DOM state class to keep button text aligned with selection state
This exercise catches stale labels after repeated clicks and reinforces reading state back from the element

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