as pretty as a picture
US /æz ˈprɪt.i æz ə ˈpɪk.tʃər/
UK /æz ˈprɪt.i æz ə ˈpɪk.tʃər/

1.
very attractive or beautiful
:
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The little girl looked as pretty as a picture in her new dress.
•
The garden was as pretty as a picture with all the flowers in bloom.