She is on cloud nine after passing her exam.
cloud nine
idiom B1
Often in the phrase on cloud nine: a state of bliss, elation or happiness.
Origin
first recorded 19th c. folk etymologyMid-20th-century American; earlier versions used cloud seven and eight, so the popular link to cloud type 9 (cumulonimbus) in the 1896 International Cloud Atlas is probably folk etymology.
He was on cloud nine when he finally received the job offer he had been waiting for all year.
After the long-awaited announcement of their engagement, the couple spent the entire evening on cloud nine, seemingly oblivious to the bustling crowd around them.