* {
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background: #f0f0f0;
    margin: 0;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    padding: 20px;
}

h1 {
    color: #333;
}

.login-container {
    max-width: 400px;
    margin: 100px auto;
    background: white;
    padding: 30px;
    border: 1px solid #ddd;
}

.login-container h1 {
    text-align: center;
    margin-bottom: 20px;
}

input[type="password"] {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #ccc;
    font-size: 16px;
}

button {
    padding: 10px;
    background: #333;
    color: white;
    border: none;
    font-size: 16px;
    cursor: pointer;
}

button:hover {
    background: #555;
}

button:focus {
    outline: 2px solid #666;
    outline-offset: 2px;
}

#loginForm button,
#messageForm button {
    width: auto;
    padding: 10px 20px;
}

#loginSection button {
    width: 100%;
}

#message, #loginMessage {
    margin-top: 15px;
    text-align: center;
}

.chat-container {
    max-width: 800px;
    margin: 20px auto;
    background: white;
    border: 1px solid #ddd;
}

#loginSection {
    padding: 30px;
}

#chatSection {
    display: flex;
    flex-direction: column;
    height: 600px;
    overflow: hidden;
}

.chat-header {
    padding: 15px;
    background: #333;
    color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chat-header h2 {
    margin: 0;
    color: white;
}

.chat-header div {
    display: flex;
    align-items: center;
    gap: 10px;
}

#logoutBtn {
    padding: 8px 15px;
    font-size: 14px;
}

#messagesContainer {
    height: 450px;
    overflow-y: auto;
    padding: 20px;
    background: #fafafa;
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
}

.message {
    margin-bottom: 15px;
    padding: 10px;
    border-radius: 5px;
    max-width: 70%;
}

.message.sent {
    background: #333;
    color: white;
    align-self: flex-end;
    text-align: right;
}

.message.received {
    background: #e0e0e0;
    color: #333;
    align-self: flex-start;
}

.message-role {
    font-size: 12px;
    font-weight: bold;
    display: block;
    margin-bottom: 5px;
}

.message-content {
    margin-bottom: 5px;
}

.message-time {
    font-size: 11px;
    opacity: 0.7;
}

#messageForm {
    display: flex;
    padding: 15px;
    border-top: 1px solid #ddd;
    background: white;
    flex-shrink: 0;
}

#messageInput {
    flex: 1;
    padding: 10px;
    border: 1px solid #ccc;
    font-size: 16px;
    margin-right: 10px;
}

#messageInput:focus,
input[type="password"]:focus {
    outline: 2px solid #333;
    border-color: #333;
}

@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    .chat-container,
    .container {
        max-width: 100%;
    }
    
    .login-container {
        margin: 50px auto;
        padding: 20px;
    }
    
    #chatSection {
        height: calc(100vh - 40px);
    }
    
    .message {
        max-width: 85%;
    }
    
    .chat-header h2 {
        font-size: 18px;
    }
    
    #logoutBtn {
        padding: 6px 12px;
        font-size: 13px;
    }
}