There are times you need to change an element’s CSS classes at runtime. But when changing classes, it’s sometimes best to apply style details conditionally. For example, imagine your view has a pager. Pagers are often used to navigate larger sets of items. When navigating, it can be helpful to show the user the page they’re currently on. The style of the item is conditionally set, based on the current page that’s being viewed. A pager in this case may…