body {
    font-family: sans-serif;
    margin: 0;
    line-height: 1.6;
    background-color: #f4f4f4;
    color: #333;
}

header {
    background: #333;
    color: #fff;
    padding: 1rem 0;
    text-align: center;
}

header h1 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
    background-color: purple;
}

header nav ul {
    padding: 0;
    margin: 0;
    list-style: none;
}

header nav ul li {
    display: inline;
    margin: 0 15px;
}

header nav a {
    color: #ccc;
    text-decoration: none;
    font-size: 1.2rem;
}

.welcome-section {
    height: 60vh;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

main section {
    padding: 2rem;
    text-align: center;
    display: none;
}

main section.active {
    display: block;
}

main section.welcome-section.active {
    display: flex;
}

#registration ul {
    list-style-type: none;
    padding: 0;
}

.agenda-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.agenda-table th, .agenda-table td {
    border: 1px solid #ddd;
    padding: 8px;
    text-align: left;
}

.agenda-table th {
    background-color: #f2f2f2;
}


@media (max-width: 768px) {
    header nav ul li {
        display: block;
        margin: 10px 0;
    }
}