<div class="topbar">
    <span class="menu-btn" onclick="toggleSidebar()">☰</span>
    <span>Welcome, <?php echo htmlspecialchars($_SESSION['username']); ?></span>
</div>

<script>
function toggleSidebar() {
    document.getElementById("sidebar").classList.toggle("collapsed");
    document.getElementById("main").classList.toggle("collapsed");
}
</script>
