body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    color: #333;
}

header {
    background: #333;
    color: #fff;
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header a {
    color: #fff;
    text-decoration: none;
    margin: 0 10px;
}

main {
    padding: 20px;
    max-width: 800px;
    margin: auto;
    min-height: 400px;
}

footer {
    background: #f4f4f4;
    text-align: center;
    padding: 10px;
    position: relative;
    bottom: 0;
    width: 100%;
}

.form-group {
    margin-bottom: 15px;
}
input[type="text"], input[type="email"], textarea {
    width: 100%;
    padding: 8px;
    margin-top: 5px;
    box-sizing: border-box;
}
button {
    background: #333;
    color: white;
    padding: 10px 15px;
    border: none;
    cursor: pointer;
}
button:hover {
    background: #555;
}

.success { color: green; background: #e2f0d9; padding: 10px; }
.error { color: red; background: #fce4d6; padding: 10px; }