<div class="sidebar">
    <h2>📊 Admin Panel</h2>
    <a href="dashboard.php" class="<?= basename($_SERVER['PHP_SELF'])=='dashboard.php' ? 'active' : '' ?>">🏠 Dashboard</a>
    <a href="lists.php" class="<?= basename($_SERVER['PHP_SELF'])=='lists.php' ? 'active' : '' ?>">📋 Lists</a>
    <a href="templates.php" class="<?= basename($_SERVER['PHP_SELF'])=='templates.php' ? 'active' : '' ?>">📄 Templates</a>
    <a href="campaigns.php" class="<?= basename($_SERVER['PHP_SELF'])=='campaigns.php' ? 'active' : '' ?>">📧 Campaigns</a>
    <a href="contacts.php" class="<?= basename($_SERVER['PHP_SELF'])=='contacts.php' ? 'active' : '' ?>">👥 Contacts</a>
    <a href="logout.php">🚪 Logout</a>
</div>
