* {
    box-sizing: border-box;
}
html, body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100vh; /* Full screen height */
    font-family: sans-serif;
}
form {
    width: 100%;
    max-width: 400px; /* Limit on large screens */
    margin: 20px auto; /* Center it */
    padding: 20px;
}
input, button {
    width: 100%;
    padding: 15px;
    margin-bottom: 15px;
    font-size: 16px; /* Prevents iOS auto-zoom on focus */
    border: 1px solid #ccc;
    border-radius: 5px;
}
button {
    background: #007bff;
    color: white;
    font-weight: bold;
}

@media (max-width: 600px) {
    form {
        margin: 10px;
        padding: 15px;
    }
    input, button {
        padding: 20px; /* Bigger touch targets (min 44px recommended) */
        font-size: 18px;
    }
}