diff --git a/api.php b/api.php
index 3dee428..b0c9353 100644
--- a/api.php
+++ b/api.php
@@ -1372,6 +1372,7 @@ function handleSaveAdjustedResult() {
     $check_to_cp = [
         'Color Contrast'      => ['04'],
         'Image Accessibility' => ['13'],
+        'Heading Structure'   => ['14'],
     ];
     $cp_to_check = [];
     foreach ($check_to_cp as $checkName => $cpIds) {
diff --git a/enterprise_pdf_checker.py b/enterprise_pdf_checker.py
index 555bcc9..3d1684a 100644
--- a/enterprise_pdf_checker.py
+++ b/enterprise_pdf_checker.py
@@ -1311,22 +1311,41 @@ Respond in JSON format:
             return
 
         struct_tree = catalog["/StructTreeRoot"]
-        headings = []
+        if hasattr(struct_tree, 'get_object'):
+            struct_tree = struct_tree.get_object()
 
-        def walk_tree(element):
+        # Load RoleMap so custom tag names (e.g. /Heading1) resolve to standard ones (/H1)
+        role_map = {}
+        if "/RoleMap" in struct_tree:
+            rm = struct_tree["/RoleMap"]
+            if hasattr(rm, 'get_object'):
+                rm = rm.get_object()
+            try:
+                for key, value in rm.items():
+                    role_map[str(key)] = str(value)
+            except (AttributeError, TypeError):
+                pass
+
+        headings = []
+        HEADING_TAGS = {"/H1", "/H2", "/H3", "/H4", "/H5", "/H6"}
+
+        def walk_tree(element, depth=0):
+            if depth > 100:
+                return
             try:
                 if hasattr(element, 'get_object'):
                     element = element.get_object()
                 if isinstance(element, dict):
                     tag = str(element.get("/S", ""))
-                    if tag in ["/H1", "/H2", "/H3", "/H4", "/H5", "/H6"]:
-                        headings.append(int(tag[2]))
+                    mapped_tag = role_map.get(tag, tag)
+                    if mapped_tag in HEADING_TAGS:
+                        headings.append(int(mapped_tag[2]))
                     kids = element.get("/K", [])
                     if isinstance(kids, list):
                         for kid in kids:
-                            walk_tree(kid)
+                            walk_tree(kid, depth + 1)
                     elif kids:
-                        walk_tree(kids)
+                        walk_tree(kids, depth + 1)
             except (AttributeError, TypeError, KeyError):
                 pass
 
diff --git a/js/results.js b/js/results.js
index 65ffce8..b165208 100644
--- a/js/results.js
+++ b/js/results.js
@@ -446,7 +446,7 @@ function displayScoreBreakdown(breakdown) {
 }
 
 // Maps H-type Matterhorn checkpoint IDs to the Score Breakdown check names that drive them
-const CP_TO_CHECK = { '04': 'Color Contrast', '13': 'Image Accessibility' };
+const CP_TO_CHECK = { '04': 'Color Contrast', '13': 'Image Accessibility', '14': 'Heading Structure' };
 
 function displayMatterhorn(summary) {
     const card = document.getElementById('matterhornCard');
@@ -459,9 +459,9 @@ function displayMatterhorn(summary) {
     const cpMap = {};
     summary.checkpoints.forEach(cp => { cpMap[cp.id] = cp; });
 
-    // Compute effective status: H-type FAIL → MANUAL_PASS if linked check is overridden
+    // Compute effective status: FAIL → MANUAL_PASS if linked check is overridden
     function effectiveStatus(cp) {
-        if (cp.how === 'H' && cp.status === 'FAIL') {
+        if (cp.status === 'FAIL') {
             const linked = CP_TO_CHECK[cp.id];
             if (linked && overriddenChecks.has(linked)) return 'MANUAL_PASS';
         }
@@ -503,7 +503,7 @@ function displayMatterhorn(summary) {
                     <button class="btn-unoverride" onclick="unoverrideCheck('${escapeAttr(linked)}')">&#x21A9; Undo</button>`;
             } else if (effStatus === 'PASS') {
                 statusHtml = `<span class="mh-pass">&#x2713; PASS</span>`;
-            } else if (effStatus === 'FAIL' && cp.how === 'H' && CP_TO_CHECK[cp.id]) {
+            } else if (effStatus === 'FAIL' && CP_TO_CHECK[cp.id]) {
                 const linked = CP_TO_CHECK[cp.id];
                 statusHtml = `<span class="mh-fail">&#x2717; FAIL</span>
                     <button class="btn-mark-passed" onclick="overrideCheck('${escapeAttr(linked)}')">&#x2713; Mark as Passed</button>`;