diff --git a/archivebox/templates/core/snapshot.html b/archivebox/templates/core/snapshot.html
index a982a792..2632fc16 100644
--- a/archivebox/templates/core/snapshot.html
+++ b/archivebox/templates/core/snapshot.html
@@ -833,11 +833,12 @@
             }
             #main-frame-wrapper {
                 width: 100%;
-                height: calc(100vh - 210px);
+                height: auto;
                 border-top: 3px solid #aa1e55;
                 overflow: hidden;
                 order: 2;
-                flex: 0 0 auto;
+                flex: 1 1 auto;
+                min-height: 0;
                 display: flex;
                 flex-direction: column;
             }
@@ -857,7 +858,7 @@
             }
             .full-page-wrapper {
                 width: 100%;
-                height: calc(100vh - 210px);
+                min-height: 0;
             }
             .snapshot-empty-state {
                 display: flex;
@@ -1027,9 +1028,6 @@
                 height: 32px;
                 max-height: 32px;
             }
-            #main-frame-wrapper.iframe-large {
-                height: calc(100vh - 70px);
-            }
             .preview-hidden {
                 display: none !important;
             }
@@ -2094,7 +2092,6 @@
                 console.log('Collapsing Snapshot header...')
                 jQuery('.header-toggle').text('▸')
                 jQuery('.header-bottom').hide()
-                jQuery('#main-frame-wrapper').addClass('iframe-large')
                 try {
                     localStorage.setItem("archivebox-snapshot-header-visible", "false")
                 } catch (e) {
@@ -2105,7 +2102,6 @@
                 console.log('Expanding Snapshot header...')
                 jQuery('.header-toggle').text('▾')
                 jQuery('.header-bottom').show()
-                jQuery('#main-frame-wrapper').removeClass('iframe-large')
                 try {
                     localStorage.setItem("archivebox-snapshot-header-visible", "true")
                 } catch (e) {
diff --git a/archivebox/tests/test_ui_admin_snapshot.py b/archivebox/tests/test_ui_admin_snapshot.py
index 3d0dcde2..442afbea 100644
--- a/archivebox/tests/test_ui_admin_snapshot.py
+++ b/archivebox/tests/test_ui_admin_snapshot.py
@@ -694,9 +694,8 @@ class TestSnapshotProgressStats:
 
         assert "full-page-iframe" in rendered
         assert "index.jsonl?preview=1" in rendered
-        assert "#main-frame-wrapper.iframe-large" in rendered
-        assert "jQuery('#main-frame-wrapper').addClass('iframe-large')" in rendered
-        assert "jQuery('#main-frame-wrapper').removeClass('iframe-large')" in rendered
+        assert "height: calc(100vh - 210px)" not in rendered
+        assert "iframe-large" not in rendered
 
 
 class TestAdminSnapshotListView: