#app{font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;display:flex;justify-content:center;align-items:center;min-height:100vh;background-color:#f3f3f3}.login-button{display:block;margin:10px auto;background-color:#007bff;color:#fff;padding:10px 20px;cursor:pointer;border-radius:5px;font-size:16px}.chat-container{width:100%;max-width:600px;background-color:#fff;border:1px solid #ddd;border-radius:5px;overflow:hidden}.logo{display:block;max-width:90%;margin:10px auto}.messages{padding:20px;max-height:400px;overflow-y:auto}.message{margin-bottom:10px;padding:8px 12px;border-radius:5px}.message.user{background-color:#007bff;color:#fff;align-self:flex-end}.message.bot{background-color:#eee;color:#333}.input-form{display:flex;background-color:#f8f8f8;padding:10px;border-top:1px solid #ddd}input{flex:1;border:none;outline:none;padding:10px}button{border:none;background-color:#007bff;color:#fff;padding:10px 20px;cursor:pointer;margin-left:10px;border-radius:5px}.spinner{border:4px solid rgba(0,0,0,.1);width:36px;height:36px;border-radius:50%;border-top-color:#007bff;animation:spin 1s linear infinite;margin:10px auto}@keyframes spin{0%{transform:rotate(0deg)}to{transform:rotate(1turn)}}