diff --git a/CHANGELOG.md b/CHANGELOG.md
index 55a7452..4355491 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
 ## [Unreleased]
 
+### Changed
+- **Dual-ring map markers** — map markers now encode two scores visually: inner core = primary score, outer ring = secondary score. Markets hub and country overview show Market Score (core) + Opportunity Score (ring). Opportunity map shows Opportunity Score (core) + Market Score (ring). City venue maps unchanged (navy dots). Color scale upgraded from 3-tier (green/amber/red) to 5-tier (deep green ≥80, teal ≥60, amber ≥40, orange-red ≥20, red <20) with distinct luminance at each tier for colorblind safety. Markers < 18px fall back to single-layer (no ring). Muted markers (cities without articles) show dashed ring outline. Highlighted markers (user's geo city) get blue outer glow. Opportunity map markers with score ≥75 pulse gently to highlight top investment targets. Tooltip lines now have inline color dots matching marker layers. All map scripts share a single `map-markers.js` module (`PNMarkers.scoreColor` + `PNMarkers.makeIcon`), replacing 3 duplicated implementations.
+
 ### Added
 - **Geo headers on city/region hubs** — Cloudflare geo headers (`CF-IPCountry`, `CF-IPCity`) now used across location-based pages. Opportunity map pre-selects and auto-loads the user's country. Country overview maps highlight the user's city with a blue ring (best-effort CF-IPCity name match). `window.__GEO` JS global injected via `base.html` for client-side map code.
 
diff --git a/web/src/padelnomics/admin/templates/admin/partials/article_preview_doc.html b/web/src/padelnomics/admin/templates/admin/partials/article_preview_doc.html
index a160193..36af07e 100644
--- a/web/src/padelnomics/admin/templates/admin/partials/article_preview_doc.html
+++ b/web/src/padelnomics/admin/templates/admin/partials/article_preview_doc.html
@@ -10,6 +10,7 @@
 <body>
   <div class="article-body">{{ body_html | safe }}</div>
   <script>window.LEAFLET_JS_URL = '{{ url_for("static", filename="vendor/leaflet/leaflet.min.js") }}';</script>
+  <script src="{{ url_for('static', filename='js/map-markers.js') }}"></script>
   <script src="{{ url_for('static', filename='js/article-maps.js') }}"></script>
 </body>
 </html>
diff --git a/web/src/padelnomics/admin/templates/admin/template_preview.html b/web/src/padelnomics/admin/templates/admin/template_preview.html
index 82858c6..58b0bc9 100644
--- a/web/src/padelnomics/admin/templates/admin/template_preview.html
+++ b/web/src/padelnomics/admin/templates/admin/template_preview.html
@@ -34,5 +34,6 @@
   </div>
 
   <script>window.LEAFLET_JS_URL = '{{ url_for("static", filename="vendor/leaflet/leaflet.min.js") }}';</script>
+  <script src="{{ url_for('static', filename='js/map-markers.js') }}"></script>
   <script src="{{ url_for('static', filename='js/article-maps.js') }}"></script>
 {% endblock %}
diff --git a/web/src/padelnomics/content/templates/article_detail.html b/web/src/padelnomics/content/templates/article_detail.html
index 2820e01..5e055a6 100644
--- a/web/src/padelnomics/content/templates/article_detail.html
+++ b/web/src/padelnomics/content/templates/article_detail.html
@@ -61,5 +61,6 @@
 
 {% block scripts %}
 <script>window.LEAFLET_JS_URL = '{{ url_for("static", filename="vendor/leaflet/leaflet.min.js") }}';</script>
+<script src="{{ url_for('static', filename='js/map-markers.js') }}"></script>
 <script src="{{ url_for('static', filename='js/article-maps.js') }}"></script>
 {% endblock %}
diff --git a/web/src/padelnomics/content/templates/markets.html b/web/src/padelnomics/content/templates/markets.html
index 7e0d883..b62a09b 100644
--- a/web/src/padelnomics/content/templates/markets.html
+++ b/web/src/padelnomics/content/templates/markets.html
@@ -19,17 +19,22 @@
   <div id="markets-map" style="height:420px; border-radius:12px;" class="mb-4"></div>
 
   <!-- Map legend -->
-  <div class="mb-6" style="display:flex; gap:1.5rem; align-items:center; font-size:0.82rem; color:#64748B;">
+  <div class="mb-6" style="display:flex; flex-wrap:wrap; gap:1rem 1.5rem; align-items:center; font-size:0.82rem; color:#64748B;">
     <span style="display:flex; align-items:center; gap:0.35rem;">
-      <span style="display:inline-block; width:12px; height:12px; border-radius:50%; background:#16A34A; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
-      <span style="display:inline-block; width:18px; height:18px; border-radius:50%; background:#16A34A; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
-      {{ t.mkt_legend_size }}
+      <span style="font-weight:600;">◉</span> inner = Market Score
+      &nbsp;<span style="font-weight:600;">○</span> ring = Opportunity Score
+    </span>
+    <span style="display:flex; align-items:center; gap:0.3rem;">
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#15803D;"></span>≥80
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#0D9488;margin-left:4px;"></span>≥60
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#D97706;margin-left:4px;"></span>≥40
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#EA580C;margin-left:4px;"></span>≥20
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#DC2626;margin-left:4px;"></span>&lt;20
     </span>
     <span style="display:flex; align-items:center; gap:0.35rem;">
-      <span style="display:inline-block; width:14px; height:14px; border-radius:50%; background:#16A34A; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
-      <span style="display:inline-block; width:14px; height:14px; border-radius:50%; background:#D97706; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
-      <span style="display:inline-block; width:14px; height:14px; border-radius:50%; background:#DC2626; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
-      {{ t.mkt_legend_color }}
+      <span style="display:inline-block; width:12px; height:12px; border-radius:50%; background:#64748B; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
+      <span style="display:inline-block; width:18px; height:18px; border-radius:50%; background:#64748B; border:2px solid white; box-shadow:0 1px 3px rgba(0,0,0,0.2);"></span>
+      {{ t.mkt_legend_size }}
     </span>
   </div>
 
@@ -83,28 +88,20 @@
 
 {% block scripts %}
 <script src="{{ url_for('static', filename='vendor/leaflet/leaflet.min.js') }}"></script>
+<script src="{{ url_for('static', filename='js/map-markers.js') }}"></script>
 <script>
 (function() {
+  var sc = PNMarkers.scoreColor;
   var map = L.map('markets-map', {scrollWheelZoom: false}).setView([48.5, 10], 4);
   L.tileLayer('https://{s}.basemaps.cartocdn.com/light_all/{z}/{x}/{y}{r}.png', {
     attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OSM</a> &copy; <a href="https://carto.com/">CARTO</a>',
     maxZoom: 18
   }).addTo(map);
 
-  function scoreColor(score) {
-    if (score >= 60) return '#16A34A';
-    if (score >= 30) return '#D97706';
-    return '#DC2626';
-  }
-
-  function makeIcon(size, color) {
-    var s = Math.round(size);
-    return L.divIcon({
-      className: '',
-      html: '<div class="pn-marker" style="width:' + s + 'px;height:' + s + 'px;background:' + color + ';opacity:0.82;"></div>',
-      iconSize: [s, s],
-      iconAnchor: [s / 2, s / 2],
-    });
+  function dot(hex, filled) {
+    return filled
+      ? '<span style="display:inline-block;width:8px;height:8px;border-radius:50%;background:' + hex + ';vertical-align:middle;margin-right:4px;"></span>'
+      : '<span style="display:inline-block;width:8px;height:8px;border-radius:50%;border:2px solid ' + hex + ';vertical-align:middle;margin-right:4px;"></span>';
   }
 
   var data = {{ map_countries | tojson }};
@@ -114,13 +111,13 @@
     data.forEach(function(c) {
       if (!c.lat || !c.lon) return;
       var size = 12 + 44 * Math.sqrt(c.total_venues / maxV);
-      var color = scoreColor(c.avg_market_score);
-      var oppColor = scoreColor(c.avg_opportunity_score || 0);
+      var coreHex = sc(c.avg_market_score);
+      var ringHex = sc(c.avg_opportunity_score || 0);
       var tip = '<strong>' + c.country_name_en + '</strong><br>'
-        + c.total_venues + ' venues · ' + c.city_count + ' cities<br>'
-        + '<span style="color:' + color + ';font-weight:600;">Padelnomics Market Score: ' + c.avg_market_score + '/100</span><br>'
-        + '<span style="color:' + oppColor + ';font-weight:600;">Padelnomics Opportunity Score: ' + (c.avg_opportunity_score || 0) + '/100</span>';
-      L.marker([c.lat, c.lon], { icon: makeIcon(size, color) })
+        + dot(coreHex, true) + '<span style="color:' + coreHex + ';font-weight:600;">Market Score: ' + c.avg_market_score + '/100</span><br>'
+        + dot(ringHex, false) + '<span style="color:' + ringHex + ';font-weight:600;">Opportunity Score: ' + (c.avg_opportunity_score || 0) + '/100</span><br>'
+        + '<span style="color:#94A3B8;font-size:0.75rem;">' + c.total_venues + ' venues · ' + c.city_count + ' cities</span>';
+      L.marker([c.lat, c.lon], { icon: PNMarkers.makeIcon({ size: size, coreColor: coreHex, ringColor: ringHex }) })
         .bindTooltip(tip, { className: 'map-tooltip', direction: 'top', offset: [0, -Math.round(size / 2)] })
         .on('click', function() { window.location = '/' + lang + '/markets/' + c.country_slug; })
         .addTo(map);
diff --git a/web/src/padelnomics/public/templates/opportunity_map.html b/web/src/padelnomics/public/templates/opportunity_map.html
index 1105528..0fbe294 100644
--- a/web/src/padelnomics/public/templates/opportunity_map.html
+++ b/web/src/padelnomics/public/templates/opportunity_map.html
@@ -38,20 +38,26 @@
   <div id="opportunity-map"></div>
   <div id="map-data" style="display:none;"></div>
 
-  <div class="mt-4 text-sm text-slate">
-    <strong>Circle size:</strong> population &nbsp;|&nbsp;
-    <strong>Color:</strong>
-    <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#16A34A;vertical-align:middle;margin:0 4px"></span>High (≥60) &nbsp;
-    <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#D97706;vertical-align:middle;margin:0 4px"></span>Mid (30–60) &nbsp;
-    <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#DC2626;vertical-align:middle;margin:0 4px"></span>Low (&lt;30)
+  <div class="mt-4 text-sm text-slate" style="display:flex; flex-wrap:wrap; gap:0.5rem 1.5rem; align-items:center;">
+    <span><strong>◉</strong> inner = Opportunity Score &nbsp;<strong>○</strong> ring = Market Score</span>
+    <span style="display:flex; align-items:center; gap:0.3rem;">
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#15803D;"></span>≥80
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#0D9488;margin-left:4px;"></span>≥60
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#D97706;margin-left:4px;"></span>≥40
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#EA580C;margin-left:4px;"></span>≥20
+      <span style="display:inline-block;width:10px;height:10px;border-radius:50%;background:#DC2626;margin-left:4px;"></span>&lt;20
+    </span>
+    <span><strong>Size:</strong> population</span>
   </div>
 </main>
 {% endblock %}
 
 {% block scripts %}
 <script src="{{ url_for('static', filename='vendor/leaflet/leaflet.min.js') }}"></script>
+<script src="{{ url_for('static', filename='js/map-markers.js') }}"></script>
 <script>
 (function() {
+  var sc = PNMarkers.scoreColor;
   var TILES = 'https://{s}.basemaps.cartocdn.com/light_all/{z}/{x}/{y}{r}.png';
   var TILES_ATTR = '&copy; <a href="https://www.openstreetmap.org/copyright">OSM</a> &copy; <a href="https://carto.com/">CARTO</a>';
 
@@ -61,22 +67,6 @@
   var oppLayer = L.layerGroup().addTo(map);
   var refLayer = L.layerGroup().addTo(map);
 
-  function oppColor(score) {
-    if (score >= 60) return '#16A34A';
-    if (score >= 30) return '#D97706';
-    return '#DC2626';
-  }
-
-  function makeIcon(size, color) {
-    var s = Math.round(size);
-    return L.divIcon({
-      className: '',
-      html: '<div class="pn-marker" style="width:' + s + 'px;height:' + s + 'px;background:' + color + ';opacity:0.8;"></div>',
-      iconSize: [s, s],
-      iconAnchor: [s / 2, s / 2],
-    });
-  }
-
   var REF_ICON = L.divIcon({
     className: '',
     html: '<div class="pn-venue" style="background:#94A3B8;border-color:white;opacity:0.7;"></div>',
@@ -90,6 +80,12 @@
          : (p || '');
   }
 
+  function dot(hex, filled) {
+    return filled
+      ? '<span style="display:inline-block;width:8px;height:8px;border-radius:50%;background:' + hex + ';vertical-align:middle;margin-right:4px;"></span>'
+      : '<span style="display:inline-block;width:8px;height:8px;border-radius:50%;border:2px solid ' + hex + ';vertical-align:middle;margin-right:4px;"></span>';
+  }
+
   function renderMap() {
     oppLayer.clearLayers();
     refLayer.clearLayers();
@@ -113,16 +109,22 @@
     oppData.forEach(function(loc) {
       if (!loc.lat || !loc.lon) return;
       var size = 8 + 40 * Math.sqrt((loc.population || 1) / maxPop);
-      var color = oppColor(loc.opportunity_score);
+      var coreHex = sc(loc.opportunity_score);
+      var ringHex = sc(loc.market_score || 0);
       var dist = loc.nearest_padel_court_km != null
         ? loc.nearest_padel_court_km.toFixed(1) + ' km to nearest court'
         : 'No nearby courts';
-      var mktColor = loc.market_score >= 60 ? '#16A34A' : (loc.market_score >= 30 ? '#D97706' : '#DC2626');
       var tip = '<strong>' + loc.location_name + '</strong><br>'
-        + '<span style="color:' + color + ';font-weight:600;">Padelnomics Opportunity Score: ' + loc.opportunity_score + '/100</span><br>'
-        + '<span style="color:' + mktColor + ';font-weight:600;">Padelnomics Market Score: ' + (loc.market_score || 0) + '/100</span><br>'
-        + dist + ' · Pop. ' + fmtPop(loc.population);
-      L.marker([loc.lat, loc.lon], { icon: makeIcon(size, color) })
+        + dot(coreHex, true) + '<span style="color:' + coreHex + ';font-weight:600;">Opportunity Score: ' + loc.opportunity_score + '/100</span><br>'
+        + dot(ringHex, false) + '<span style="color:' + ringHex + ';font-weight:600;">Market Score: ' + (loc.market_score || 0) + '/100</span><br>'
+        + '<span style="color:#94A3B8;font-size:0.75rem;">' + dist + ' · Pop. ' + fmtPop(loc.population) + '</span>';
+      var icon = PNMarkers.makeIcon({
+        size: size,
+        coreColor: coreHex,
+        ringColor: ringHex,
+        pulse: loc.opportunity_score >= 75,
+      });
+      L.marker([loc.lat, loc.lon], { icon: icon })
         .bindTooltip(tip, { className: 'map-tooltip', direction: 'top', offset: [0, -Math.round(size / 2)] })
         .addTo(oppLayer);
       bounds.push([loc.lat, loc.lon]);
diff --git a/web/src/padelnomics/static/css/input.css b/web/src/padelnomics/static/css/input.css
index 4183c15..c09932d 100644
--- a/web/src/padelnomics/static/css/input.css
+++ b/web/src/padelnomics/static/css/input.css
@@ -879,8 +879,10 @@
 .leaflet-tooltip.map-tooltip::before { display: none; }
 .leaflet-tooltip.map-tooltip strong { color: white; }
 
-/* Polished variable-size circle — white border + drop shadow */
+/* ── Dual-ring map markers ── */
+/* Container: sets size, white border, shadow, hover */
 .pn-marker {
+  position: relative;
   border-radius: 50%;
   border: 2.5px solid white;
   box-shadow: 0 2px 8px rgba(0,0,0,0.28);
@@ -891,25 +893,57 @@
   box-shadow: 0 3px 12px rgba(0,0,0,0.38);
   transform: scale(1.1);
 }
-
-/* User's city highlight — blue ring on top of score-colored bubble */
-.pn-marker--highlight {
-  border: 3px solid #3B82F6;
-  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.3), 0 2px 8px rgba(0,0,0,0.28);
+/* Outer ring: secondary score color */
+.pn-marker__ring {
+  position: absolute;
+  inset: 0;
+  border-radius: 50%;
+  opacity: 0.65;
+}
+/* Inner core: primary score color, inset 5px from container edges */
+.pn-marker__core {
+  position: absolute;
+  inset: 5px;
+  border-radius: 50%;
+  border: 1.5px solid rgba(255,255,255,0.5);
+}
+/* Compact fallback: marker < 18px, no ring — core fills container */
+.pn-marker--compact .pn-marker__core {
+  inset: 0;
+  border: none;
 }
 
-/* Non-article city markers: faded + dashed border, no click affordance */
+/* User's city highlight — blue outer glow */
+.pn-marker--highlight {
+  border: 2.5px solid #3B82F6;
+  box-shadow: 0 0 0 3px rgba(59,130,246,0.25), 0 2px 8px rgba(0,0,0,0.28);
+}
+
+/* Non-article city markers: faded, dashed ring outline, no click */
 .pn-marker--muted {
-  opacity: 0.45;
-  border: 2px dashed rgba(255,255,255,0.6);
+  opacity: 0.4;
   cursor: default;
-  filter: saturate(0.7);
+  filter: saturate(0.6) brightness(1.1);
+}
+.pn-marker--muted .pn-marker__ring {
+  background: transparent !important;
+  border: 1.5px dashed rgba(255,255,255,0.6);
+  opacity: 1;
 }
 .pn-marker--muted:hover {
   transform: none;
   box-shadow: 0 2px 8px rgba(0,0,0,0.28);
 }
 
+/* Pulse animation — opportunity map only, score >= 75 */
+.pn-marker--pulse .pn-marker__ring {
+  animation: marker-pulse 2.5s ease-in-out infinite;
+}
+@keyframes marker-pulse {
+  0%, 100% { transform: scale(1);    opacity: 0.65; }
+  50%      { transform: scale(1.35); opacity: 0.25; }
+}
+
 /* Small fixed venue dot */
 .pn-venue {
   width: 10px;
diff --git a/web/src/padelnomics/static/js/article-maps.js b/web/src/padelnomics/static/js/article-maps.js
index 6e2b2b6..a767c70 100644
--- a/web/src/padelnomics/static/js/article-maps.js
+++ b/web/src/padelnomics/static/js/article-maps.js
@@ -4,6 +4,8 @@
  * Looks for #country-map and #city-map elements. If neither exists, does nothing.
  * Expects data-* attributes on the map elements and a global LEAFLET_JS_URL
  * variable pointing to the Leaflet JS bundle.
+ *
+ * Depends on map-markers.js (window.PNMarkers) being loaded first.
  */
 (function() {
   var countryMapEl = document.getElementById('country-map');
@@ -12,22 +14,13 @@
 
   var TILES = 'https://{s}.basemaps.cartocdn.com/light_all/{z}/{x}/{y}{r}.png';
   var TILES_ATTR = '&copy; <a href="https://www.openstreetmap.org/copyright">OSM</a> &copy; <a href="https://carto.com/">CARTO</a>';
+  var sc = PNMarkers.scoreColor;
 
-  function scoreColor(score) {
-    if (score >= 60) return '#16A34A';
-    if (score >= 30) return '#D97706';
-    return '#DC2626';
-  }
-
-  function makeIcon(size, color, muted) {
-    var s = Math.round(size);
-    var cls = 'pn-marker' + (muted ? ' pn-marker--muted' : '');
-    return L.divIcon({
-      className: '',
-      html: '<div class="' + cls + '" style="width:' + s + 'px;height:' + s + 'px;background:' + color + ';"></div>',
-      iconSize: [s, s],
-      iconAnchor: [s / 2, s / 2],
-    });
+  function tooltipDot(hex, filled) {
+    var style = filled
+      ? 'display:inline-block;width:8px;height:8px;border-radius:50%;background:' + hex + ';vertical-align:middle;margin-right:4px;'
+      : 'display:inline-block;width:8px;height:8px;border-radius:50%;border:2px solid ' + hex + ';vertical-align:middle;margin-right:4px;';
+    return '<span style="' + style + '"></span>';
   }
 
   function initCountryMap(el) {
@@ -45,22 +38,29 @@
           if (!c.lat || !c.lon) return;
           var size = 10 + 36 * Math.sqrt((c.padel_venue_count || 1) / maxV);
           var hasArticle = c.has_article !== false;
-          var color = scoreColor(c.market_score);
+          var coreHex = sc(c.market_score);
+          var ringHex = sc(c.opportunity_score || 0);
           var pop = c.population >= 1000000
             ? (c.population / 1000000).toFixed(1) + 'M'
             : (c.population >= 1000 ? Math.round(c.population / 1000) + 'K' : (c.population || ''));
-          var oppColor = c.opportunity_score >= 60 ? '#16A34A' : (c.opportunity_score >= 30 ? '#D97706' : '#DC2626');
           var tip = '<strong>' + c.city_name + '</strong><br>'
+            + tooltipDot(coreHex, true) + '<span style="color:' + coreHex + ';font-weight:600;">Market Score: ' + Math.round(c.market_score) + '/100</span><br>'
+            + tooltipDot(ringHex, false) + '<span style="color:' + ringHex + ';font-weight:600;">Opportunity Score: ' + Math.round(c.opportunity_score || 0) + '/100</span><br>'
+            + '<span style="color:#94A3B8;font-size:0.75rem;">'
             + (c.padel_venue_count || 0) + ' venues'
-            + (pop ? ' · ' + pop : '')
-            + '<br><span style="color:' + color + ';font-weight:600;">Padelnomics Market Score: ' + Math.round(c.market_score) + '/100</span>'
-            + '<br><span style="color:' + oppColor + ';font-weight:600;">Padelnomics Opportunity Score: ' + Math.round(c.opportunity_score || 0) + '/100</span>';
+            + (pop ? ' · ' + pop : '') + '</span>';
           if (hasArticle) {
             tip += '<br><span style="color:#94A3B8;font-size:0.75rem;">Click to explore →</span>';
           } else {
             tip += '<br><span style="color:#94A3B8;font-size:0.75rem;">Coming soon</span>';
           }
-          var marker = L.marker([c.lat, c.lon], { icon: makeIcon(size, color, !hasArticle) })
+          var icon = PNMarkers.makeIcon({
+            size: size,
+            coreColor: coreHex,
+            ringColor: ringHex,
+            muted: !hasArticle,
+          });
+          var marker = L.marker([c.lat, c.lon], { icon: icon })
             .bindTooltip(tip, { className: 'map-tooltip', direction: 'top', offset: [0, -Math.round(size / 2)] })
             .addTo(map);
           if (hasArticle) {
@@ -78,13 +78,11 @@
           });
           if (match && match.lat && match.lon) {
             var hSize = 10 + 36 * Math.sqrt((match.padel_venue_count || 1) / maxV);
-            var hs = Math.round(hSize);
-            var hColor = scoreColor(match.market_score);
-            var hIcon = L.divIcon({
-              className: '',
-              html: '<div class="pn-marker pn-marker--highlight" style="width:' + hs + 'px;height:' + hs + 'px;background:' + hColor + ';"></div>',
-              iconSize: [hs, hs],
-              iconAnchor: [hs / 2, hs / 2],
+            var hIcon = PNMarkers.makeIcon({
+              size: hSize,
+              coreColor: sc(match.market_score),
+              ringColor: sc(match.opportunity_score || 0),
+              highlight: true,
             });
             L.marker([match.lat, match.lon], { icon: hIcon }).addTo(map);
           }
diff --git a/web/src/padelnomics/static/js/map-markers.js b/web/src/padelnomics/static/js/map-markers.js
new file mode 100644
index 0000000..e0e3996
--- /dev/null
+++ b/web/src/padelnomics/static/js/map-markers.js
@@ -0,0 +1,67 @@
+/**
+ * Shared map marker utilities — dual-ring design with 5-tier color scale.
+ *
+ * Exposes window.PNMarkers = { scoreColor, makeIcon }
+ *
+ * scoreColor(score) → hex color string (5 tiers, colorblind-safe luminance steps)
+ * makeIcon(opts)    → L.divIcon with dual-ring HTML
+ *
+ * opts = {
+ *   size:       number,           // marker diameter in px
+ *   coreColor:  string,           // hex for inner core (primary score)
+ *   ringColor:  string,           // hex for outer ring (secondary score)
+ *   muted:      boolean,          // dashed ring, no click affordance
+ *   highlight:  boolean,          // blue outer glow (user's geo city)
+ *   pulse:      boolean,          // gentle ring pulse (high opportunity)
+ * }
+ */
+(function() {
+  'use strict';
+
+  // 5-tier color scale — distinct luminance at each tier for deuteranopia/protanopia
+  function scoreColor(score) {
+    if (score >= 80) return '#15803D'; // deep green — excellent
+    if (score >= 60) return '#0D9488'; // teal — good
+    if (score >= 40) return '#D97706'; // amber — moderate
+    if (score >= 20) return '#EA580C'; // orange-red — below avg
+    return '#DC2626';                  // red — poor
+  }
+
+  var COMPACT_THRESHOLD_PX = 18;
+
+  function makeIcon(opts) {
+    var s = Math.round(opts.size);
+    var compact = s < COMPACT_THRESHOLD_PX;
+
+    var cls = 'pn-marker';
+    if (compact)        cls += ' pn-marker--compact';
+    if (opts.muted)     cls += ' pn-marker--muted';
+    if (opts.highlight) cls += ' pn-marker--highlight';
+    if (opts.pulse && !opts.muted) cls += ' pn-marker--pulse';
+
+    var html;
+    if (compact || !opts.ringColor) {
+      // Single-layer fallback: core fills entire marker
+      html = '<div class="' + cls + '" style="width:' + s + 'px;height:' + s + 'px;">'
+           + '<div class="pn-marker__core" style="background:' + opts.coreColor + ';"></div>'
+           + '</div>';
+    } else {
+      html = '<div class="' + cls + '" style="width:' + s + 'px;height:' + s + 'px;">'
+           + '<div class="pn-marker__ring" style="background:' + opts.ringColor + ';"></div>'
+           + '<div class="pn-marker__core" style="background:' + opts.coreColor + ';"></div>'
+           + '</div>';
+    }
+
+    return L.divIcon({
+      className: '',
+      html: html,
+      iconSize: [s, s],
+      iconAnchor: [s / 2, s / 2],
+    });
+  }
+
+  window.PNMarkers = {
+    scoreColor: scoreColor,
+    makeIcon: makeIcon,
+  };
+})();
