diff --git a/catalog.php b/catalog.php
index c979ff3..2aca8b7 100644
--- a/catalog.php
+++ b/catalog.php
@@ -13,28 +13,28 @@ $user = new User($con, $_SESSION['user']);
 }
 
 $possiblePages = [
-  0,
-  1,
-  2,
-  3,
-  4,
-  5,
-  6,
-  7,
-  8,
-  9,
-  10,
-  11
+  "hats",
+  "shirts",
+  "tshirts",
+  "pants",
+  "gears",
+  "packages",
+  "heads",
+  "torso",
+  "leftarm",
+  "rightarm",
+  "leftleg",
+  "rightleg"
 ];
 
-if(isset($_GET["p"])) {
-  $page = (int) $_GET["p"];
+if(isset($_GET["filter"])) {
+  $page = $_GET["filter"];
   if(!in_array($page,$possiblePages)) {
     header('location: /catalog');
     exit;
   }
 } else {
-  $page = 0;
+  $page = null;
 }
 
 $getitstarted = new PartyStarter;
@@ -59,31 +59,32 @@ $getitstarted->header();
           <br>
           <h4>Category</h4>
         </li>
-        <a href="/catalog" class="list-group-item<?php if($page == 0) { ?> active<?php } ?>" aria-current="true">All categories</a>
-        <a href="?p=1" class="list-group-item<?php if($page == 1) { ?> active<?php } ?>">Hats</a>
-        <a href="?p=2" class="list-group-item<?php if($page == 2) { ?> active<?php } ?>">Shirts</a>
-        <a href="?p=3" class="list-group-item<?php if($page == 3) { ?> active<?php } ?>">Pants</a>
-        <a href="?p=4" class="list-group-item<?php if($page == 4) { ?> active<?php } ?>">Gears</a>
-        <a href="?p=5" class="list-group-item<?php if($page == 5) { ?> active<?php } ?>">Packages</a>
-        <button class="list-group-item text-start<?php if($page == 6 || $page == 7 || $page == 8 || $page == 9 || $page == 10 || $page == 11) { ?> active<?php } ?>" type="button" data-bs-toggle="dropdown" aria-expanded="false">Body parts</button>
+        <a href="/catalog" class="list-group-item<?php if($page == null) { ?> active<?php } ?>" aria-current="true">All categories</a>
+        <a href="?filter=hats" class="list-group-item<?php if($page == "hats") { ?> active<?php } ?>">Hats</a>
+        <a href="?filter=shirts" class="list-group-item<?php if($page == "shirts") { ?> active<?php } ?>">Shirts</a>
+		<a href="?filter=tshirts" class="list-group-item<?php if($page == "tshirts") { ?> active<?php } ?>">T-shirts</a>
+        <a href="?filter=pants" class="list-group-item<?php if($page == "pants") { ?> active<?php } ?>">Pants</a>
+        <a href="?filter=gears" class="list-group-item<?php if($page == "gears") { ?> active<?php } ?>">Gears</a>
+        <a href="?filter=packages" class="list-group-item<?php if($page == "packages") { ?> active<?php } ?>">Packages</a>
+        <button class="list-group-item text-start<?php if($page == "heads" || $page == "torso" || $page == "leftarm" || $page == "rightarm" || $page == "leftleg" || $page == "rightleg") { ?> active<?php } ?>" type="button" data-bs-toggle="dropdown" aria-expanded="false">Body parts</button>
         <ul class="dropdown-menu">
           <li>
-            <a class="dropdown-item<?php if($page == 6) { ?> active<?php } ?>" href="?p=6">Heads</a>
+            <a class="dropdown-item<?php if($page == "heads") { ?> active<?php } ?>" href="?filter=heads">Heads</a>
           </li>
           <li>
-            <a class="dropdown-item<?php if($page == 7) { ?> active<?php } ?>" href="?p=7">Torso</a>
+            <a class="dropdown-item<?php if($page == "torso") { ?> active<?php } ?>" href="?filter=torso">Torso</a>
           </li>
           <li>
-            <a class="dropdown-item<?php if($page == 8) { ?> active<?php } ?>" href="?p=8">Left arm</a>
+            <a class="dropdown-item<?php if($page == "leftarm") { ?> active<?php } ?>" href="?filter=leftarm">Left arm</a>
           </li>
           <li>
-            <a class="dropdown-item<?php if($page == 9) { ?> active<?php } ?>" href="?p=9">Right arm</a>
+            <a class="dropdown-item<?php if($page == "rightarm") { ?> active<?php } ?>" href="?filter=rightarm">Right arm</a>
           </li>
           <li>
-            <a class="dropdown-item<?php if($page == 10) { ?> active<?php } ?>" href="?p=10">Left leg</a>
+            <a class="dropdown-item<?php if($page == "leftleg") { ?> active<?php } ?>" href="?filter=leftleg">Left leg</a>
           </li>
           <li>
-            <a class="dropdown-item<?php if($page == 11) { ?> active<?php } ?>" href="?p=11">Right leg</a>
+            <a class="dropdown-item<?php if($page == "rightleg") { ?> active<?php } ?>" href="?filter=rightleg">Right leg</a>
           </li>
         </ul>
         <li class="list-group-item">