body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
    color: #333;
}

header {
    background-color: #006400;
    color: #fff;
    padding: 20px 0;
    text-align: center;
}

.nav-menu {
    list-style: none;
    padding: 0;
}

.nav-menu li {
    display: inline;
    margin: 0 15px;
}

.nav-menu a {
    color: #fff;
    text-decoration: none;
}

h1, h2 {
    margin: 0;
    padding: 10px;
}

section {
    padding: 20px;
    margin: 20px;
    background: #fff;
    border-radius: 5px;
}

.btn {
    display: inline-block;
    padding: 10px 20px;
    color: #fff;
    background: #006400;
    text-decoration: none;
    border-radius: 5px;
    margin-top: 10px;
}

.btn:hover {
    background: #004d00;
}

footer {
    text-align: center;
    background: #333;
    color: #fff;
    padding: 10px 0;
    margin-top: 20px;
}