diff --git a/e2e/board.smoke.spec.ts b/e2e/board.smoke.spec.ts
index 620b09e..cbbc2ef 100644
--- a/e2e/board.smoke.spec.ts
+++ b/e2e/board.smoke.spec.ts
@@ -27,6 +27,11 @@ async function waitForSave(page: Page, action: () => Promise<void>) {
 test('move, folder expansion, empty-board pan, desktop wheel zoom, mobile pinch, and reload persistence', async ({ page }) => {
   await page.goto('/?level=e2e-level&edit=1')
   await expect(page.getByRole('heading', { name: 'Browser Safety Test' })).toBeVisible()
+  const temporalLayering = await page.evaluate(() => ({
+    links: Number.parseInt(getComputedStyle(document.querySelector('.temporal-links')!).zIndex, 10),
+    timeline: Number.parseInt(getComputedStyle(document.querySelector('.timeline')!).zIndex, 10),
+  }))
+  expect(temporalLayering.links).toBeGreaterThan(temporalLayering.timeline)
   await expect(page.locator('.documents-panel')).toHaveClass(/\bclosed\b/)
   await expect(page.locator('.brief-panel')).toBeVisible()
   await expect(page.getByRole('button', { name: 'Case brief', exact: true })).toContainText('2')
diff --git a/src/styles.css b/src/styles.css
index 445a922..34e6a4d 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -190,7 +190,7 @@ button:focus-visible { outline: 2px solid #e99a44; outline-offset: 2px; }
 .concept-editor-list { max-height: 280px; overflow: auto; border: 1px solid #8d968f; background: #d4d5cd; }.concept-editor-row { display: grid; grid-template-columns: 150px 1fr 125px 30px; gap: 6px; padding: 7px; border-bottom: 1px solid #9fa59e; }.concept-editor-row input, .concept-editor-row select { min-width: 0; border: 1px solid #7d8780; background: #e8e5d8; padding: 7px; font: 9px IBM Plex Mono; }.concept-editor-row button { border: 0; color: #713c2d; }
 .file-drop-overlay { position: absolute; z-index: 20; inset: 14px; border: 2px dashed #e19a4d; background: #0a211de8; display: grid; place-items: center; pointer-events: none; }.file-drop-overlay > div { width: 290px; height: 150px; border: 1px solid #5e786f; background: #102c25; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 10px; box-shadow: 9px 10px #020b09; color: #d99a58; }.file-drop-overlay b { font: 600 12px IBM Plex Mono; letter-spacing: .08em; }.file-drop-overlay span { font: 9px IBM Plex Mono; color: #78928a; letter-spacing: .12em; }
 .timeline { background: #0d231e; border-top: 1px solid #3c544d; display: grid; grid-template-columns: 180px 1fr 165px; align-items: center; padding: 0 25px; z-index: 8; }
-.temporal-links { position: fixed; z-index: 7; inset: 0; width: 100vw; height: 100vh; pointer-events: none; overflow: visible; }.temporal-links line { stroke: #8b9792; stroke-width: 1; opacity: .42; vector-effect: non-scaling-stroke; }
+.temporal-links { position: fixed; z-index: 9; inset: 0; width: 100vw; height: 100vh; pointer-events: none; overflow: visible; }.temporal-links line { stroke: #8b9792; stroke-width: 1; opacity: .42; vector-effect: non-scaling-stroke; }
 .timeline-label { border-right: 1px solid #314a43; height: 67px; display: flex; flex-direction: column; justify-content: center; }
 .timeline-label b { font: 600 14px IBM Plex Mono; margin: 4px 0; }.timeline-label button { width: max-content; max-width: 170px; padding: 0; overflow: hidden; color: #a07142; background: transparent; border: 0; text-overflow: ellipsis; white-space: nowrap; text-align: left; cursor: pointer; font: 8px IBM Plex Mono; }
 .timeline-track { height: 75px; margin: 0 43px; position: relative; }