diff --git a/app/pages/deep-research/index.vue b/app/pages/deep-research/index.vue
index c6a2f1fe..d3e7d506 100644
--- a/app/pages/deep-research/index.vue
+++ b/app/pages/deep-research/index.vue
@@ -17,6 +17,8 @@
 import { mapboxTokenIfChosen } from '~/utils/mapProvider'
 
 // ONE scrollbar: no footer here, and the page itself never scrolls; the gallery's own content does.
+// The header still leaves as on every other page: it hides while the gallery is scrolled down
+// (see watchPaneForHeader) and the gallery then takes the whole screen.
 definePageMeta({ hideFooter: true })
 
 const { t, locale } = useI18n()
@@ -36,6 +38,7 @@ useHead({
 const host = ref<HTMLElement | null>(null)
 let gallery: HTMLElement | null = null
 let resizeObs: ResizeObserver | null = null
+let unwatchPane: (() => void) | null = null
 
 // The gallery fills the viewport below the header. The header's height differs between desktop
 // and phone (and with the language), so it is measured, not assumed.
@@ -45,6 +48,31 @@ function fitBelowHeader() {
   document.documentElement.style.setProperty('--rg-header-h', h + 'px')
 }
 
+// The gallery scrolls inside its own main pane, so a finger (or a wheel) over it scrolls that
+// pane and never the page. The header leaves the way it does on every other page: once the pane
+// is scrolled down a little, <html> gets rg-header-hidden (the header hides and the gallery takes
+// the full screen); back at the pane's top, the header returns. One scroller, so nothing fights
+// the pane's own momentum. Only a scroller at least half the gallery's height counts (its main
+// pane), not a small list such as a legend sheet's.
+function watchPaneForHeader(el: HTMLElement, root: ShadowRoot) {
+  const onScroll = (e: Event) => {
+    const pane = e.target
+    if (!(pane instanceof HTMLElement) || pane.clientHeight < el.clientHeight / 2) return
+    const cls = document.documentElement.classList
+    if (pane.scrollTop > 8) cls.add('rg-header-hidden')
+    else if (pane.scrollTop <= 0) cls.remove('rg-header-hidden')
+  }
+  // Scroll events don't bubble, but they do pass the shadow root in the capture phase.
+  root.addEventListener('scroll', onScroll, { capture: true, passive: true })
+  unwatchPane = () => root.removeEventListener('scroll', onScroll, true)
+}
+
+// The gallery attaches its shadow root once its script has defined the element.
+function whenShadowRoot(el: HTMLElement, done: (root: ShadowRoot) => void, tries = 50) {
+  if (el.shadowRoot) done(el.shadowRoot)
+  else if (tries > 0) setTimeout(() => whenShadowRoot(el, done, tries - 1), 100)
+}
+
 onMounted(() => {
   fitBelowHeader()
   // The gallery is sized to the viewport below the header; a sub-pixel header height must not add a
@@ -76,6 +104,10 @@ onMounted(() => {
   gallery.setAttribute('provider', provider)
   gallery.setAttribute('profile-config', JSON.stringify(galleryConfig))
   host.value?.appendChild(gallery)
+  customElements.whenDefined('doxa-maps-spa').then(() => {
+    const el = gallery
+    if (el) whenShadowRoot(el, root => watchPaneForHeader(el, root))
+  })
 })
 
 watch(locale, (lang) => {
@@ -83,9 +115,10 @@ watch(locale, (lang) => {
 })
 
 onBeforeUnmount(() => {
-  document.documentElement.classList.remove('rg-no-page-scroll')
-  document.documentElement.classList.remove('rg-gallery-mounted')
+  document.documentElement.classList.remove('rg-no-page-scroll', 'rg-gallery-mounted', 'rg-header-hidden')
   resizeObs?.disconnect()
+  unwatchPane?.()
+  unwatchPane = null
   gallery?.remove()
   gallery = null
 })
@@ -131,6 +164,15 @@ html.rg-no-page-scroll body {
   overflow: hidden;
 }
 
+/* While the gallery is scrolled down, the header is away and the gallery takes the whole screen,
+   as the header leaves on every other page. Back at the gallery's top, the header returns. */
+html.rg-header-hidden #masthead {
+  display: none;
+}
+html.rg-header-hidden .research-gallery-page {
+  height: 100svh;
+}
+
 /* The site header is z-index 1500 (blocks/_header.scss); the gallery's info dialog is a full-viewport
    layer at z-index 1000, full-screen on a phone, so the header covered the dialog's title and close
    button there. While the gallery is shown, the header sits just under the dialog: 999 still keeps it,
diff --git a/app/pages/research/index.vue b/app/pages/research/index.vue
index 4624dcf5..19e8e342 100644
--- a/app/pages/research/index.vue
+++ b/app/pages/research/index.vue
@@ -51,8 +51,9 @@ useTextHighlight()
         :profile-config="researchProfileConfig"
         class="rounded-xlg"
       />
-      <!-- Under the map: the way to the full set of research maps, the hidden Deep Research page. -->
-      <p class="text-center">
+      <!-- Under the map: the way to the full set of research maps, the hidden Deep Research page.
+           Small, like the homepage's "Explore our research maps" line under its map. -->
+      <p class="text-center deep-research-line">
         {{ t('Want Deeper Research?') }}
         <NuxtLink
           class="light-link"
@@ -70,3 +71,10 @@ useTextHighlight()
     />
   </div>
 </template>
+
+<style scoped>
+/* The same size as the homepage's link under its map (.research-map-link in pages/index.vue). */
+.deep-research-line {
+  font-size: 1.2rem;
+}
+</style>