body {
    font-family: Arial, sans-serif;
    background: #f4f4f4;
    padding: 30px;
}
form {
    background: #fff;
    padding: 20px;
    max-width: 800px;
    margin: auto;
}
input, textarea, button {
    width: 100%;
    margin: 10px 0;
    padding: 8px;
}
button {
    background: #222;
    color: #fff;
    border: none;
    cursor: pointer;
}
.error {
    color: red;
    text-align: center;
}