No, the Catholic Church does not have any official or written dress code. That is laughable.
You may be thinking of the old “rule of 3.” Female modesty in dress: the neckline must be no lower than 3 inches below the collar bone, and the hem of dress should fall 3 inches below the knee!
1262.2 Men, in a church or outside a church, while they are assisting at sacred rites, shall be bare-headed, unless the approved mores of the people or peculiar circumstances of things determine otherwise; women, however, shall have a covered head and be modestly dressed, especially when they approach the table of the Lord.
Of course the post Vatican II, JPII 1983 Code of Canon Law abrogated this Church Law.