en and (min-width: 320px) and (max-width: 640px){ .chat1{right:10px;width:24px;height:24px;bottom:1.15rem;border-radius:100%;padding:5px;line-height: 26px;} .chat2{width:100%;height:100vh;right:0;border-radius: 0;} .chat-textarea textarea{height: 120px} }