Use 'perk up' to describe a quick, positive change in someone's emotions.

Emotional Uplift

'Perk up' often implies a temporary or short-term improvement in mood.

Temporary Effect

It suggests a subtle or gentle increase in liveliness, not an extreme one.

Use it to describe enhancing the look of something in a simple, positive way.

Usually refers to small, easy improvements rather than complete transformations.

It can imply a quick and effective way to make something look better.