jQuery.when()

Provides a way to execute callback functions based on zero or more Thenable objects, usually Deferred objects that represent asynchronous events.

.css()

Get the value of a computed style property for the first element in the set of matched elements or set one or more CSS properties for every matched element.

jQuery.Deferred()

A factory function that returns a chainable utility object with methods to register multiple callbacks into callback queues, invoke callback queues, and relay the success or failure state of any synchronous or asynchronous function.