body {
    background: #e8f5e9;
    font-family: Arial, sans-serif;
}

.container {
    width: 420px;
    background: white;
    margin: auto;
    margin-top: 40px;
    padding: 20px;
    border-radius: 10px;
}

h2 {
    text-align: center;
    color: green;
}

.subtitle {
    text-align: center;
    font-size: 14px;
    color: #555;
}

label {
    font-weight: bold;
}

input {
    width: 100%;
    padding: 8px;
    margin-bottom: 10px;
}

button {
    width: 100%;
    padding: 10px;
    background: green;
    color: white;
    border: none;
    font-size: 16px;
    cursor: pointer;
}

#result, #level, #tips {
    margin-top: 12px;
    font-weight: bold;
}