body {
    margin: 0;
    padding: 0;
    background-color: #121212;
    color: #e0e0e0;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.container {
    max-width: 800px;
    margin: 40px auto;
    padding: 30px;
    background-color: #1e1e1e;
    border-radius: 10px;
    box-shadow: 0 0 20px rgba(0,0,0,0.5);
}

h1 {
    text-align: center;
    color: #00e5ff;
}

.subtitle {
    text-align: center;
    color: #aaa;
    margin-bottom: 30px;
}

textarea {
    width: 100%;
    padding: 15px;
    margin-bottom: 15px;
    background-color: #2a2a2a;
    border: 1px solid #444;
    color: #fff;
    border-radius: 5px;
    resize: vertical;
    font-size: 16px;
}

button {
    padding: 10px 20px;
    background-color: #00e5ff;
    border: none;
    color: black;
    font-weight: bold;
    font-size: 16px;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: #00bcd4;
}

.success {
    background-color: #2e7d32;
    padding: 15px;
    color: #d0ffd0;
    margin-bottom: 20px;
    border-radius: 5px;
    font-weight: bold;
    text-align: center;
}

.history {
    margin-top: 30px;
}

.message {
    margin-bottom: 15px;
    padding: 15px;
    border-radius: 8px;
    background-color: #2c2c2c;
}

.message.user {
    border-left: 5px solid #00e5ff;
}

.message.ai {
    border-left: 5px solid #4caf50;
}

.loading {
    background-color: #333;
    color: #00e5ff;
    padding: 10px;
    margin-top: 20px;
    border-left: 5px solid #00e5ff;
    border-radius: 5px;
    font-style: italic;
    font-size: 16px;
}