/* Base styles */
* {
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f5f5f5;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 1rem;
    background-color: #ffffff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
}

h1 {
    text-align: center;
    color: #333333;
}

.chat_history {
    border: 1px solid #e0e0e0;
    padding: 1em;
    height: 300px;
    overflow-y: scroll;
    margin-bottom: 1rem;
    background-color: #fafafa;
}

.chat_history p {
    margin: 0.5em 0;
}

.user_message {
    color: #424242;
}

.gpt_message {
    color: #1a73e8;
}

.input_section {
    display: flex;
    align-items: center;
    background-color: #f5f5f5;
    padding: 0.5em;
    border: 1px solid #e0e0e0;
}

#user_input {
    flex-grow: 1;
    margin-right: 1rem;
    padding: 0.5em;
    border: none;
    outline: none;
}

#send_button {
    background-color: #1a73e8;
    color: #ffffff;
    padding: 0.5em 1em;
    border: none;
    cursor: pointer;
}

/* Responsive styles */
@media (max-width: 768px) {
    .container {
        padding: 1rem 0.5rem;
    }

    .chat_history {
        height: 200px;
    }

    #user_input {
        font-size: 14px;
    }

    #send_button {
        font-size: 14px;
        padding: 5px 10px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 1rem 0.25rem;
    }

    .input_section {
        flex-direction: column;
        align-items: stretch;
    }

    #user_input {
        margin-bottom: 0.5rem;
        margin-right: 0;
    }

    #send_button {
        width: 100%;
    }
}