admin_index.php

<?php require_once("config.php"); ?>

    <?php include("admin_header.php") ?>

    <?php include("sidebar.php") ?>


    <div class="w3-overlay w3-hide-large w3-animate-opacity" onclick="w3_close()" style="cursor:pointer" title="close side menu" id="myOverlay"></div>

    <div class="w3-main" style="margin-left:300px;margin-top:43px;">

      <?php include("admin_overview.php") ?>

</div>

<script>
var mySidebar = document.getElementById("mySidebar");

var overlayBg = document.getElementById("myOverlay");

function w3_open() {
  if (mySidebar.style.display === 'block') {
    mySidebar.style.display = 'none';
    overlayBg.style.display = "none";
  } else {
    mySidebar.style.display = 'block';
    overlayBg.style.display = "block";
  }
}

function w3_close() {
  mySidebar.style.display = "none";
  overlayBg.style.display = "none";
}
</script>

</body>
</html>