body {
font-family: Arial, sans-serif;
margin: 20px;
padding: 20px;
}

h1 {
text-align: center;
color: #003366;
}

p {
margin-bottom: 15px;
}

.invitation {
border: 1px solid #003366;
background-color: #f2f2f2;
padding: 20px;
max-width: 500px;
margin: 0 auto;
}

.date-time {
font-size: 18px;
font-weight: bold;
}

.venue {
font-size: 16px;
}

.rsvp {
font-size: 14px;
font-style: italic;
}