diff --git a/.changeset/page-header-z-index-below-drawers.md b/.changeset/page-header-z-index-below-drawers.md
new file mode 100644
index 0000000000..31d4dd178e
--- /dev/null
+++ b/.changeset/page-header-z-index-below-drawers.md
@@ -0,0 +1,20 @@
+---
+'@hyperdx/app': patch
+---
+
+fix(z-index): keep sticky header below drawers and drawers above the fullscreen tile modal
+
+Two related z-index regressions:
+
+- `PageHeader` was pinned at `z-index: 100`, but app drawers opt into a
+  much lower stack via `ZIndexContext` (`contextZIndex + 10`, so a
+  top-level drawer renders at `z-index: 10`). The sticky header therefore
+  floated above the drawer overlay. The header now sits at `z-index: 2` so
+  drawer overlays reliably cover the page chrome while the header still
+  wins against normal scrolling content.
+- `FullscreenPanelModal` used Mantine's default modal z-index (`200`) and
+  didn't propagate it through `ZIndexContext`. Clicking a row in a
+  fullscreen search tile opened a `DBRowSidePanel` drawer at `z-index: 10`
+  that was hidden behind the modal. The modal now follows the existing
+  `contextZIndex + 10` pattern and wraps its children in a
+  `ZIndexContext.Provider`, so child drawers stack on top of it.
diff --git a/packages/app/src/components/FullscreenPanelModal.tsx b/packages/app/src/components/FullscreenPanelModal.tsx
index e7f9c61c4a..1b3df9d793 100644
--- a/packages/app/src/components/FullscreenPanelModal.tsx
+++ b/packages/app/src/components/FullscreenPanelModal.tsx
@@ -1,6 +1,8 @@
 import { Box, Modal } from '@mantine/core';
 import { useHotkeys } from '@mantine/hooks';
 
+import { useZIndex, ZIndexContext } from '@/zIndex';
+
 export default function FullscreenPanelModal({
   opened,
   onClose,
@@ -15,6 +17,13 @@ export default function FullscreenPanelModal({
   // YouTube-style 'f' key to toggle fullscreen
   useHotkeys([['f', () => opened && onClose()]]);
 
+  // Stack on top of any ancestor drawer/modal (`contextZIndex + 10`) and
+  // expose this value via `ZIndexContext` so any drawer/popover opened from
+  // inside the fullscreen view (e.g. clicking a row in a search tile) lands
+  // above the modal instead of being hidden behind it.
+  const contextZIndex = useZIndex();
+  const modalZIndex = contextZIndex + 10;
+
   return (
     <Modal
       opened={opened}
@@ -22,6 +31,7 @@ export default function FullscreenPanelModal({
       title={title}
       fullScreen
       transitionProps={{ transition: 'fade', duration: 200 }}
+      zIndex={modalZIndex}
       styles={{
         body: {
           height: 'calc(100vh - 80px)',
@@ -42,17 +52,19 @@ export default function FullscreenPanelModal({
       trapFocus={false}
       lockScroll
     >
-      <Box
-        h="100%"
-        w="100%"
-        p="md"
-        style={{
-          overflow: 'auto',
-          position: 'relative',
-        }}
-      >
-        {children}
-      </Box>
+      <ZIndexContext.Provider value={modalZIndex}>
+        <Box
+          h="100%"
+          w="100%"
+          p="md"
+          style={{
+            overflow: 'auto',
+            position: 'relative',
+          }}
+        >
+          {children}
+        </Box>
+      </ZIndexContext.Provider>
     </Modal>
   );
 }
diff --git a/packages/app/src/components/PageHeader.module.scss b/packages/app/src/components/PageHeader.module.scss
index 3408b57ead..1bde82d825 100644
--- a/packages/app/src/components/PageHeader.module.scss
+++ b/packages/app/src/components/PageHeader.module.scss
@@ -14,7 +14,12 @@
   padding: 0 var(--mantine-spacing-sm);
   position: sticky;
   top: 0;
-  z-index: 100;
+
+  /* Top-level drawers in this app are rendered at z-index 10
+     (`contextZIndex + 10` from `ZIndexContext`, see e.g. `DBRowSidePanel`).
+     Sit 8 below that so the drawer overlay always covers the page chrome,
+     while the header still floats above normal scrolling content. */
+  z-index: 2;
 }
 
 /* Applied automatically when a `stickyRow` is provided: the chrome scrolls
@@ -40,7 +45,10 @@
   padding: var(--mantine-spacing-sm);
   position: sticky;
   top: 0;
-  z-index: 100;
+
+  /* Match `.header` — sit 8 below the top-level drawer z-index (10) so
+     drawer overlays always cover this row. */
+  z-index: 2;
 }
 
 /* Applied when the sticky row sits directly under chrome AND is not