Idiom 5: (AS) RIGHT AS RAIN
Meaning: in good health again; perfectly fine
Most typically this phrase is used to refer to health. We often use it to reassure people.
You look absolutely exhausted. Why don’t you go to bed early and I’m sure by the morning you’ll be as right as rain.
Stop worrying about your interview. With your skills and experience you’ll be right as rain, you’ll see.