body {
    margin: 0;
    font-family: Arial, sans-serif;
    background-color: #001f3f;
    color: #ffffff;
}

header {
    background-color: #000000;
    padding: 10px 20px;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header h1 {
    margin: 0;
    color: #ffffff;
}

nav a {
    color: #ffffff;
    text-decoration: none;
    margin: 0 10px;
    font-size: 14px;
}

nav a:hover {
    text-decoration: underline;
}

main {
    padding: 20px;
}

.dark-section {
    background-color: #002855;
    padding: 20px;
    margin: 10px 0;
}

.light-section {
    background-color: #004080;
    padding: 20px;
    margin: 10px 0;
}

.certificates-container {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.certificate-card {
    width: 200px;
    border: 2px solid #ffffff;
    padding: 10px;
}

footer {
    background-color: #000000;
    text-align: center;
    padding: 10px;
}
s