body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

header {
    background-color: #4CAF50;
    color: white;
    text-align: center;
    padding: 1rem 0;
}

main {
    padding: 1rem;
}

input[type="text"] {
    width: 100%;
    padding: 0.5rem;
    margin-bottom: 1rem;
    border: 1px solid #ccc;
    border-radius: 4px;
}

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

li {
    padding: 0.5rem;
    border-bottom: 1px solid #ccc;
}

@media (max-width: 600px) {
    header {
        font-size: 1.2rem;
    }

    input[type="text"] {
        font-size: 1rem;
    }

    li {
        font-size: 0.9rem;
    }
}