body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 20px;
    max-width: 800px;
    margin: 0 auto;
}

h1, h2, h3 {
    color: #333;
}

form {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 5px;
}

input, select {
    width: 100%;
    padding: 5px;
    margin-bottom: 10px;
}

button {
    background-color: #4CAF50;
    color: white;
    padding: 10px 15px;
    border: none;
    cursor: pointer;
}

button:hover {
    background-color: #45a049;
}

ul {
    list-style-type: none;
    padding: 0;
}

li {
    cursor: pointer;
    padding: 5px;
    margin-bottom: 5px;
    background-color: #f0f0f0;
}

li:hover {
    background-color: #e0e0e0;
}

canvas {
    border: 1px solid #ddd;
    margin-top: 20px;
}

.flex-container {
    display: flex;
    justify-content: space-between;
}

.flex-container > div {
    flex: 1;
    margin-right: 20px;
}

#visualization {
    text-align: center;
}

#bmi-display {
    margin-top: 20px;
}

.notification {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 10px 20px;
    border-radius: 5px;
    color: white;
    font-weight: bold;
    opacity: 0.9;
    transition: opacity 0.3s ease-in-out;
}

.notification.success {
    background-color: #4CAF50;
}

.notification.info {
    background-color: #2196F3;
}

.notification.error {
    background-color: #f44336;
}

@media (max-width: 600px) {
    body {
        padding: 10px;
    }
    
    .flex-container {
        flex-direction: column;
    }
    
    .flex-container > div {
        margin-right: 0;
        margin-bottom: 20px;
    }
}