body{background-color:#1a1a1a;color:#e0e0e0;margin:0;font-family:Arial,sans-serif}.chat-app{max-width:800px;margin:0 auto;display:flex;flex-direction:column;height:100vh;background-color:#2a2a2a;border-radius:10px;overflow:hidden;box-shadow:0 0 10px rgba(0,0,0,.3);z-index:44}.chat-header{background-color:#3a3a3a;color:#e0e0e0;padding:20px;display:flex;align-items:center}.chat-header h1{margin:0;font-size:1.5rem}.back-link{margin-right:15px}.back-link img{width:24px;height:24px;filter:invert(1)}.chat-messages{flex:1;overflow-y:auto;padding:20px}.message{margin-bottom:15px}.message-content{background-color:#3a3a3a;color:#e0e0e0;padding:10px 15px;border-radius:18px;display:inline-block;max-width:80%;box-shadow:0 1px 2px hsla(0,0%,100%,.1)}.chat-input{display:flex;padding:20px;background-color:#3a3a3a}.chat-input input{flex:1;padding:10px;border:1px solid #555;border-radius:20px;font-size:16px;background-color:#2a2a2a;color:#e0e0e0}.chat-input button{background-color:#4a90e2;color:#fff;border:none;padding:10px 20px;margin-left:10px;border-radius:20px;cursor:pointer;font-size:16px}.chat-input button:hover{background-color:#3a7bd5}::-webkit-scrollbar{width:10px}::-webkit-scrollbar-track{background:#2a2a2a}::-webkit-scrollbar-thumb{background:#555;border-radius:5px}::-webkit-scrollbar-thumb:hover{background:#666}