The idiom "sea change" refers to a significant transformation or a radical shift in something. It is often used to describe a sudden and dramatic change in circumstances, behavior, or attitudes.

"Child’s play" is an idiomatic expression that means something is extremely easy or effortless to do, often because it involves a task that requires little skill or knowledge. The phrase comes from the idea of children playing and having fun without much difficulty.

The idiom "the corridors of power" refers to the place where important decisions are made or where people with influence and authority reside.

The idiom "everything but the kitchen sink" means to throw everything, even nonessential things, into a situation or task until it's overloaded and can't handle any more.

The idiom "next door" refers to a place that is very close by, within walking distance or just beyond it. It can also refer to someone who lives or works nearby or is easily accessible.