body {
    font-family: Arial, sans-serif;
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f4f7f9;
    color: #333;
}

.screen {
    display: none;
    background-color: white;
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

#start-screen {
    display: block;
}

h1 {
    color: #2c3e50;
}

h2 {
    color: #34495e;
}

p {
    line-height: 1.6;
}

button, .cta {
    padding: 12px 25px;
    margin: 10px 5px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
}

button:hover, .cta:hover {
    background-color: #2980b9;
}

button:disabled {
    background-color: #bdc3c7;
    cursor: not-allowed;
}

label {
    display: block;
    margin: 15px 0;
    padding: 15px;
    background-color: #ecf0f1;
    border-radius: 8px;
}

input[type="radio"] {
    margin-right: 10px;
}

#progress {
    text-align: centre;
    margin-bottom: 20px;
}

progress {
    width: 100%;
    height: 10px;
}

#message {
    text-align: centre;
    color: #27ae60;
    font-style: italic;
}

#error,
#form-error {
    colour: #e74c3c;
    margin: 10px 0;
}

@media (max-width: 600px) {
    body {
        padding: 10px;
    }

    button {
        width: 100%;
    }
}