diff --git a/frontend/components/dashboard/Dashboard.module.css b/frontend/components/dashboard/Dashboard.module.css
index b0371da5..f2729748 100644
--- a/frontend/components/dashboard/Dashboard.module.css
+++ b/frontend/components/dashboard/Dashboard.module.css
@@ -14052,3 +14052,123 @@
     padding: 0 13px 13px;
   }
 }
+
+/* Light-mode hard overrides for the scan terminal. Keep this block last so the
+   decision workspace cannot inherit the dark map/card palette from base rules. */
+.root:global(.light) {
+  --bg-primary: #eef7ff;
+  --bg-secondary: #e0f2fe;
+  --bg-card: #ffffff;
+  --bg-glass: rgba(255, 255, 255, 0.92);
+  --border-glass: #cfe8ff;
+  --border-subtle: rgba(125, 171, 214, 0.34);
+  --text-primary: #0f172a;
+  --text-secondary: #334155;
+  --text-muted: #475569;
+}
+
+.root:global(.light) :global(.scan-terminal.light) {
+  background:
+    radial-gradient(circle at 18% 12%, rgba(59, 130, 246, 0.12), transparent 30%),
+    linear-gradient(180deg, #eef7ff 0%, #e8f4ff 48%, #f8fbff 100%) !important;
+  color: #0f172a !important;
+}
+
+:global(html.light) .root :global(.map),
+.root:global(.light) :global(.map),
+.root:global(.light) :global(.scan-terminal.light .scan-map-shell .map),
+.root:global(.light) :global(.scan-terminal.light .scan-map-shell .leaflet-container),
+.root:global(.light) :global(.leaflet-container),
+.root:global(.light) :global(.leaflet-pane),
+.root:global(.light) :global(.leaflet-map-pane),
+.root:global(.light) :global(.leaflet-tile-pane) {
+  background: #eef7ff !important;
+}
+
+:global(html.light) .root :global(.map),
+.root:global(.light) :global(.scan-terminal.light .scan-map-shell) {
+  border-color: rgba(37, 99, 235, 0.18) !important;
+  box-shadow:
+    0 18px 40px rgba(61, 100, 145, 0.14),
+    inset 0 0 0 1px rgba(255, 255, 255, 0.72) !important;
+}
+
+:global(html.light) .root :global(.map .leaflet-tile),
+.root:global(.light) :global(.map .leaflet-tile),
+.root:global(.light) :global(.scan-terminal.light .scan-map-shell .leaflet-tile) {
+  filter: none !important;
+  opacity: 1 !important;
+}
+
+.root:global(.light) :global(.scan-city-detail-rail),
+.root:global(.light) :global(.scan-terminal.light > .detail-panel.scan-city-detail-rail) {
+  background:
+    linear-gradient(180deg, rgba(238, 247, 255, 0.98), rgba(255, 255, 255, 0.96)) !important;
+  border-color: rgba(37, 99, 235, 0.16) !important;
+  color: #0f172a !important;
+}
+
+.root:global(.light) :global(.scan-city-detail-rail .panel-header),
+.root:global(.light) :global(.scan-city-detail-rail .detail-structured-section),
+.root:global(.light) :global(.scan-city-detail-rail .detail-summary-shell),
+.root:global(.light) :global(.scan-city-detail-rail .detail-card) {
+  background: rgba(255, 255, 255, 0.74) !important;
+  border-color: rgba(125, 171, 214, 0.28) !important;
+}
+
+.root:global(.light) :global(.scan-city-detail-rail h2),
+.root:global(.light) :global(.scan-city-detail-rail h3),
+.root:global(.light) :global(.scan-city-detail-rail strong),
+.root:global(.light) :global(.scan-city-detail-rail .detail-value),
+.root:global(.light) :global(.scan-city-detail-rail .detail-summary-temp),
+.root:global(.light) :global(.scan-city-detail-rail .detail-section-head h3),
+.root:global(.light) :global(.scan-city-detail-rail .panel-title-area h2) {
+  color: #0f172a !important;
+}
+
+.root:global(.light) :global(.scan-city-detail-rail p),
+.root:global(.light) :global(.scan-city-detail-rail li),
+.root:global(.light) :global(.scan-city-detail-rail small),
+.root:global(.light) :global(.scan-city-detail-rail .panel-overline),
+.root:global(.light) :global(.scan-city-detail-rail .panel-loading-hint),
+.root:global(.light) :global(.scan-city-detail-rail .panel-meta-chip),
+.root:global(.light) :global(.scan-city-detail-rail .detail-section-kicker),
+.root:global(.light) :global(.scan-city-detail-rail .detail-label),
+.root:global(.light) :global(.scan-city-detail-rail .detail-value-muted),
+.root:global(.light) :global(.scan-city-detail-rail .detail-source-note),
+.root:global(.light) :global(.scan-city-detail-rail .detail-source-kind),
+.root:global(.light) :global(.scan-city-detail-rail .detail-mini-meta),
+.root:global(.light) :global(.scan-city-detail-rail .detail-summary-supporting),
+.root:global(.light) :global(.scan-city-detail-rail .scan-detail-city-sub),
+.root:global(.light) :global(.scan-city-detail-rail .scan-detail-volume-caption),
+.root:global(.light) :global(.scan-city-detail-rail .scan-detail-score-label),
+.root:global(.light) :global(.scan-city-detail-rail .scan-detail-empty) {
+  color: #334155 !important;
+}
+
+.root:global(.light) :global(.scan-city-detail-rail .panel-meta-chip),
+.root:global(.light) :global(.scan-city-detail-rail .panel-weather-chip),
+.root:global(.light) :global(.scan-city-detail-rail .detail-source-link),
+.root:global(.light) :global(.scan-city-detail-rail .panel-action-button-secondary),
+.root:global(.light) :global(.scan-city-detail-rail .panel-action-button-ghost) {
+  background: #eef7ff !important;
+  border-color: rgba(37, 99, 235, 0.18) !important;
+  color: #1f3654 !important;
+}
+
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-card),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-section),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-decision-band),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-market-decision),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-decision-metrics span),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-pills span) {
+  background: #eef7ff !important;
+  border-color: rgba(37, 99, 235, 0.16) !important;
+}
+
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-card p),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-card li),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-card small),
+.root:global(.light) :global(.scan-terminal.light .scan-ai-city-card span:not(.scan-ai-city-kicker)) {
+  color: #334155 !important;
+}
diff --git a/frontend/components/dashboard/ScanTerminalDashboard.tsx b/frontend/components/dashboard/ScanTerminalDashboard.tsx
index c851a8e5..6a28068a 100644
--- a/frontend/components/dashboard/ScanTerminalDashboard.tsx
+++ b/frontend/components/dashboard/ScanTerminalDashboard.tsx
@@ -78,6 +78,18 @@ function ScanTerminalScreen() {
   const aiHydrationQueueRef = useRef<string[]>([]);
   const aiHydrationRunningRef = useRef(false);
 
+  useEffect(() => {
+    const root = document.documentElement;
+    const hadLight = root.classList.contains("light");
+    const hadDark = root.classList.contains("dark");
+    root.classList.toggle("light", themeMode === "light");
+    root.classList.toggle("dark", themeMode === "dark");
+    return () => {
+      root.classList.toggle("light", hadLight);
+      root.classList.toggle("dark", hadDark);
+    };
+  }, [themeMode]);
+
   const timeSortedRows = useMemo(
     () => sortRowsByUserTime(terminalData?.rows || []),
     [terminalData?.rows],
@@ -537,7 +549,7 @@ function ScanTerminalScreen() {
 
   if (store.proAccess.loading) {
     return (
-      <div className={clsx(styles.root, detailChromeStyles.root, modalChromeStyles.root)}>
+      <div className={clsx(styles.root, detailChromeStyles.root, modalChromeStyles.root, themeMode === "light" && "light")}>
         <div className={clsx("scan-terminal", themeMode === "light" && "light")}>
           <main className="scan-data-grid">
             <div className="scan-loading-state">
@@ -557,7 +569,7 @@ function ScanTerminalScreen() {
   }
 
   return (
-    <div className={clsx(styles.root, detailChromeStyles.root, modalChromeStyles.root)}>
+    <div className={clsx(styles.root, detailChromeStyles.root, modalChromeStyles.root, themeMode === "light" && "light")}>
       <div className={clsx("scan-terminal", themeMode === "light" && "light")}>
         <main className="scan-data-grid">
           <div className="scan-topbar">
diff --git a/frontend/hooks/useLeafletMap.ts b/frontend/hooks/useLeafletMap.ts
index ebbedaf3..02b49c30 100644
--- a/frontend/hooks/useLeafletMap.ts
+++ b/frontend/hooks/useLeafletMap.ts
@@ -57,14 +57,16 @@ function getMarkerDisplayOffset(cityName: string) {
   };
 }
 
-function getMapTileUrl() {
+function getMapTileUrl(container?: Element | null) {
   if (typeof document === "undefined") {
     return MAP_TILE_URLS.dark;
   }
 
   const lightMode =
+    Boolean(container?.closest(".light")) ||
     document.documentElement.classList.contains("light") ||
     document.body.classList.contains("light") ||
+    Boolean(document.querySelector(`.${CSS.escape("light")}`)) ||
     Boolean(document.querySelector(".scan-terminal.light"));
   if (lightMode) {
     return MAP_TILE_URLS.light;
@@ -518,7 +520,7 @@ export function useLeafletMap({
     });
 
     L.control.zoom({ position: "bottomright" }).addTo(map);
-    const tileLayer = L.tileLayer(getMapTileUrl(), {
+    const tileLayer = L.tileLayer(getMapTileUrl(container), {
       attribution:
         '&copy; <a href="https://www.openstreetmap.org/">OSM</a> &copy; <a href="https://carto.com/">CARTO</a>',
       maxZoom: 19,
@@ -599,7 +601,7 @@ export function useLeafletMap({
     if (!tileLayer || typeof MutationObserver === "undefined") return;
 
     const syncMapTheme = () => {
-      tileLayer.setUrl(getMapTileUrl());
+      tileLayer.setUrl(getMapTileUrl(containerRef.current));
     };
     syncMapTheme();
 
diff --git a/src/data_collection/polymarket_readonly.py b/src/data_collection/polymarket_readonly.py
index 681ff89c..513341a0 100644
--- a/src/data_collection/polymarket_readonly.py
+++ b/src/data_collection/polymarket_readonly.py
@@ -1749,12 +1749,19 @@ class PolymarketReadOnlyLayer:
 
     def _fetch_token_market_data(self, token_id: str) -> Dict[str, Any]:
         # REST-only path: CLOB public endpoints.
-        bid = _extract_price(self._clob_get("/price", {"token_id": token_id, "side": "BUY"}))
-        ask = _extract_price(
+        # Polymarket CLOB semantics:
+        # - side=BUY returns the executable ask, i.e. the price paid to buy.
+        # - side=SELL returns the executable bid, i.e. the price received to sell.
+        buy_price = _extract_price(self._clob_get("/price", {"token_id": token_id, "side": "BUY"}))
+        sell_price = _extract_price(
             self._clob_get("/price", {"token_id": token_id, "side": "SELL"})
         )
         if self.fast_price_only:
-            buy, sell = self._resolve_trade_prices(buy=ask, sell=bid, book=None)
+            buy, sell = self._resolve_trade_prices(
+                buy=buy_price,
+                sell=sell_price,
+                book=None,
+            )
             midpoint = (buy + sell) / 2.0 if buy is not None and sell is not None else (buy or sell)
             spread = max(0.0, float(buy) - float(sell)) if buy is not None and sell is not None else None
             return {
@@ -1775,7 +1782,11 @@ class PolymarketReadOnlyLayer:
         )
         orderbook_raw = self._clob_get("/book", {"token_id": token_id})
         book, book_liquidity = self._normalize_orderbook(orderbook_raw)
-        buy, sell = self._resolve_trade_prices(buy=ask, sell=bid, book=book)
+        buy, sell = self._resolve_trade_prices(
+            buy=buy_price,
+            sell=sell_price,
+            book=book,
+        )
         if midpoint is None and buy is not None and sell is not None:
             midpoint = (buy + sell) / 2.0
         spread = max(0.0, float(buy) - float(sell)) if buy is not None and sell is not None else None
@@ -2366,22 +2377,22 @@ class PolymarketReadOnlyLayer:
         if not missing:
             return results
 
-        ask_map: Dict[str, float] = {}
-        bid_map: Dict[str, float] = {}
+        buy_map: Dict[str, float] = {}
+        sell_map: Dict[str, float] = {}
         midpoint_map: Dict[str, float] = {}
         spread_map: Dict[str, float] = {}
         last_trade_map: Dict[str, float] = {}
         book_map: Dict[str, Dict[str, Any]] = {}
 
         for chunk in self._batch_chunks(missing):
-            sell_payload = self._clob_post(
-                "/prices",
-                [{"token_id": token_id, "side": "SELL"} for token_id in chunk],
-            )
             buy_payload = self._clob_post(
                 "/prices",
                 [{"token_id": token_id, "side": "BUY"} for token_id in chunk],
             )
+            sell_payload = self._clob_post(
+                "/prices",
+                [{"token_id": token_id, "side": "SELL"} for token_id in chunk],
+            )
             midpoint_payload = (
                 self._clob_post(
                     "/midpoints",
@@ -2414,8 +2425,8 @@ class PolymarketReadOnlyLayer:
                 if include_books and not self.fast_price_only
                 else None
             )
-            ask_map.update(self._extract_batch_price_map(sell_payload, "SELL"))
-            bid_map.update(self._extract_batch_price_map(buy_payload, "BUY"))
+            buy_map.update(self._extract_batch_price_map(buy_payload, "BUY"))
+            sell_map.update(self._extract_batch_price_map(sell_payload, "SELL"))
             midpoint_map.update(self._extract_batch_scalar_map(midpoint_payload))
             spread_map.update(self._extract_batch_scalar_map(spread_payload))
             last_trade_map.update(self._extract_batch_scalar_map(last_trade_payload))
@@ -2427,13 +2438,17 @@ class PolymarketReadOnlyLayer:
         for token_id in missing:
             raw_book = book_map.get(token_id)
             book, book_liquidity = self._normalize_orderbook(raw_book)
-            ask = _extract_price(ask_map.get(token_id))
-            bid = _extract_price(bid_map.get(token_id))
+            buy_price = _extract_price(buy_map.get(token_id))
+            sell_price = _extract_price(sell_map.get(token_id))
             midpoint = _extract_price(midpoint_map.get(token_id))
             spread = _extract_price(spread_map.get(token_id))
             last_trade = _extract_price(last_trade_map.get(token_id))
 
-            buy, sell = self._resolve_trade_prices(buy=ask, sell=bid, book=book)
+            buy, sell = self._resolve_trade_prices(
+                buy=buy_price,
+                sell=sell_price,
+                book=book,
+            )
             if midpoint is None and buy is not None and sell is not None:
                 midpoint = (buy + sell) / 2.0
             if midpoint is None: