body {
	font-family: Arial, sans-serif;
	margin: 0;
	background-color: #f7f7f7;
}

header {
	background-color: #fff;
	padding: 2.5%;
	border-bottom: 1px solid black;
	position: sticky;
	top: 0;
}

h1,
h2 {
	text-align: center;
}

p {
	line-height: 1.6;
}

a {
	text-decoration: none;
	color: #238
}

a:hover {
	color: #000;
}

.nav-container {
	display: flex;
	justify-content: center;
}

.nav-link {
	font-size: 16px;
	text-align: center;
	width: 25%;
}

.disabled-link {
	pointer-events: none;
	color: gray;
}

.container {
	padding: 2.5% 10%;
}

.module {
	background-color: #fff;
	padding: 2%;
	margin-bottom: 2%;
	border-radius: 8px;
	box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}