diff --git a/src/gui/components/_legacy.py b/src/gui/components/_legacy.py
index 402becf..9d520fd 100644
--- a/src/gui/components/_legacy.py
+++ b/src/gui/components/_legacy.py
@@ -628,26 +628,19 @@ def render_sticky_footer() -> None:
     st.markdown(
         """
 <style>
-/* DIAGNOSTIC: tint every plausible bottom-area container so we can
-   see WHICH element is actually filling the visible bottom of the
-   page. Whichever color shows in the "white bar" region is the
-   element to fix. To be reverted once the right target is known. */
-[data-testid="stAppViewBlockContainer"] {
-    background: #ff5050 !important;    /* RED   = block container  */
-    min-height: calc(100vh / 0.85) !important;
-    padding-bottom: 2rem !important;
-    box-sizing: border-box !important;
-}
-[data-testid="stMain"],
-section[data-testid="stMain"] {
-    background: #50c0ff !important;    /* BLUE  = stMain           */
-    min-height: 100vh !important;
-}
+/* The view container is the element whose background paints the
+   strip between the last piece of content and the fixed footer
+   overlay (confirmed via colored-tag diagnostic). ``.stApp`` carries
+   ``zoom: 0.85`` so 100vh renders at 85% visually — divide by 0.85
+   so the container spans the full visible viewport and there's no
+   gap for its own background to show through as a "white bar". */
 [data-testid="stAppViewContainer"] {
-    background: #50ff80 !important;    /* GREEN = view container   */
+    min-height: calc(100vh / 0.85) !important;
 }
-.stApp {
-    background: #ffd000 !important;    /* GOLD  = .stApp (zoomed)  */
+[data-testid="stAppViewBlockContainer"] {
+    /* Reserve room for the fixed footer overlay (footer min-height
+       32px + 0.25rem * 2 padding ≈ 2rem). */
+    padding-bottom: 2rem !important;
 }
 #datatools-sticky-footer {
     position: fixed !important;