devil-may-care
adjective uk/ˌdev.əl.meɪˈkeər/ us/ˌdev.əl.meɪˈker/
不管不顾的，无所顾忌的，无所谓的
not considering or worrying about the results of your actions
He has a devil-may-care attitude to life. 他对自己的生活持一种相当无所谓的态度。
Synonym: happy-go-lucky