https://cssgradient.io/
https://yoon-talk.tistory.com/352
https://jae04099.tistory.com/m/entry/CSS-글씨에-그라데이션-적용하기
https://developer.mozilla.org/ko/docs/Web/CSS/background-clip
https://pixabay.com/ko/vectors/search/message icon/?manual_search=1
