:root{--primary:#8e44ad;--bg-color:#f4f7f6;--chat-bg:#fff}body{background-color:var(--bg-color);justify-content:center;margin:0;padding:20px;font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;display:flex}.app-container{background:var(--chat-bg);border-radius:12px;flex-direction:column;width:100%;max-width:800px;height:90vh;display:flex;overflow:hidden;box-shadow:0 10px 25px #0000001a}.chat-header{background-color:var(--primary);color:#fff;text-align:center;margin:0;padding:15px 20px}.chat-window{background-color:#fcfcfc;flex-grow:1;padding:20px;overflow-y:auto}.chat-form{background-color:#fff;border-top:1px solid #eee;gap:10px;padding:20px;display:flex}.chat-form input{border:2px solid #ddd;border-radius:8px;outline:none;flex-grow:1;padding:15px;font-size:1em}.chat-form button{background-color:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:8px;padding:15px 30px;font-weight:700}