Element.classList: https://developer.mozilla.org/en-US/docs/Web/API/Element/classList https://developer.mozilla.org/en-US/docs/Web/API/Element/cla... Property

Element.classList: https://developer.mozilla.org/en-US/docs/Web/API/Element/classList https://developer.mozilla.org/en-US/docs/Web/API/Element/cla... Property Accessors (Bracket Notation): https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Property_Accessors#Bracket_notation https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe... Conditional (ternary) Operator: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_Operator https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...