body{margin:0;font-family:Arial;background:#0f172a;color:white}
#app{display:flex;height:100vh}
#sidebar{width:260px;background:#020617;padding:15px}
#sidebar button{width:100%;padding:10px;background:#10b981;border:none;cursor:pointer}
#chat{flex:1;display:flex;flex-direction:column}
#messages{flex:1;padding:20px;overflow-y:auto}
.msg.user{color:#38bdf8;margin-bottom:10px}
.msg.ai{color:#a7f3d0;margin-bottom:20px}
#input{padding:15px;border:none;background:#020617;color:white}
#login{position:fixed;inset:0;display:flex;flex-direction:column;justify-content:center;align-items:center;background:#020617}
#login input,#login button{width:250px;margin:5px;padding:10px}