StyleClass manages css classes declaratively to during enter/leave animations or just to toggle classes on an element.

import { StyleClassModule } from 'primeng/styleclass';

StyleClass has two modes, toggleClass to simply add-remove a class and enter/leave animations. The target element to change the styling is defined with the selector property that accepts any valid CSS selector or keywords including @next, prev, parent, grandparent

<button pButton label="Toggle p-disabled" pStyleClass="@next" toggleClass="p-disabled"></button>
<input type="text" pInputText class="block mt-3" />

Classes to apply during enter and leave animations are specified using the enterFromClass, enterActiveClass, enterToClass, leaveFromClass, leaveActiveClass,leaveToClassproperties. In addition in case the target is an overlay, hideOnOutsideClick would be handy to hide the target if outside of the popup is clicked, or enable hideOnEscape to close the popup by listening escape key.

    <button pButton label="Show" class="mr-2" pStyleClass=".box" enterFromClass="hidden" enterActiveClass="fadein"></button>
    <button pButton label="Hide" pStyleClass=".box" leaveActiveClass="fadeout" leaveToClass="hidden"></button>

<div class="hidden animation-duration-500 box">
    <div class="flex bg-green-500 text-white align-items-center justify-content-center py-3 border-round-md mt-3 font-bold shadow-2 w-8rem h-8rem">Content</div>