What is the fine-grained topic of the following text: Since playing the Main Stage at Sea Sessions in 2016, Feibhár’s music has evolved into something more distinct, moving from a folky girl-with-a-guitar sound, into something more atmospheric and haunting, fuelled by her desire to write and arrange every aspect on Logic Pro X.
Lyrically driven, Feibhár's focus is on dark and ambient vocal harmonies, amplified by digital production elements, which carry the character driven narratives she explores in her songwriting. Only return the topic.
Feibhár's evolution in musical style and songwriting.