diff --git a/.github/workflows/deploy.yml b/.github/workflows/deploy.yml
index 41f44730..f57239fa 100644
--- a/.github/workflows/deploy.yml
+++ b/.github/workflows/deploy.yml
@@ -283,6 +283,7 @@ jobs:
           CHROMIUM_REQUIRE=1 BASE_URL=http://localhost:13581 node test-issue-1244-live-vcr-row-hints-e2e.js 2>&1 | tee -a e2e-output.txt
           BASE_URL=http://localhost:13581 node test-issue-1224-channels-mobile-ux-e2e.js 2>&1 | tee -a e2e-output.txt
           BASE_URL=http://localhost:13581 node test-issue-1236-map-mobile-e2e.js 2>&1 | tee -a e2e-output.txt
+          BASE_URL=http://localhost:13581 node test-issue-1329-map-controls-accordion-e2e.js 2>&1 | tee -a e2e-output.txt
           BASE_URL=http://localhost:13581 node test-issue-1273-qr-overlay-height-e2e.js 2>&1 | tee -a e2e-output.txt
           BASE_URL=http://localhost:13581 node test-issue-1281-location-row-e2e.js 2>&1 | tee -a e2e-output.txt
           BASE_URL=http://localhost:13581 node test-issue-1279-legend-p2-e2e.js 2>&1 | tee -a e2e-output.txt
diff --git a/public/map.js b/public/map.js
index 01b752d1..ad0423dc 100644
--- a/public/map.js
+++ b/public/map.js
@@ -262,6 +262,48 @@
       toggleBtn.setAttribute('aria-expanded', String(!controlsCollapsed));
     });
 
+    // #1329: Map controls accordion. Make each section's legend a button-
+    // style toggle with aria-expanded. On mobile (≤640px) only one section
+    // is open at a time so the panel never needs internal scrolling. On
+    // desktop the .mc-collapsed class has no visual effect (CSS only hides
+    // section bodies inside the mobile media query) so all controls stay
+    // visible — but single-open behaviour is still tracked for state
+    // consistency. See test-issue-1329-map-controls-accordion-e2e.js.
+    (function initMapControlsAccordion() {
+      const isMobile = window.innerWidth <= 640;
+      const sections = Array.from(controlsPanel.querySelectorAll('fieldset.mc-section'));
+      sections.forEach((fs, idx) => {
+        const legend = fs.querySelector('legend.mc-label');
+        if (!legend) return;
+        // Initial state: on mobile only the first section is open; on
+        // desktop all sections are open.
+        const open = !isMobile || idx === 0;
+        legend.setAttribute('role', 'button');
+        legend.setAttribute('tabindex', '0');
+        legend.setAttribute('aria-expanded', String(open));
+        fs.classList.toggle('mc-collapsed', !open);
+        const setOpen = (target, openNow) => {
+          target.setAttribute('aria-expanded', String(openNow));
+          const parent = target.closest('fieldset.mc-section');
+          if (parent) parent.classList.toggle('mc-collapsed', !openNow);
+        };
+        const onActivate = (e) => {
+          e.preventDefault();
+          const currentlyOpen = legend.getAttribute('aria-expanded') === 'true';
+          // Single-open: close every other section first.
+          sections.forEach(other => {
+            const otherLegend = other.querySelector('legend.mc-label');
+            if (otherLegend && otherLegend !== legend) setOpen(otherLegend, false);
+          });
+          setOpen(legend, !currentlyOpen);
+        };
+        legend.addEventListener('click', onActivate);
+        legend.addEventListener('keydown', (e) => {
+          if (e.key === 'Enter' || e.key === ' ') onActivate(e);
+        });
+      });
+    })();
+
     // Bind controls
     var clustersEl = document.getElementById('mcClusters');
     if (clustersEl) {
diff --git a/public/style.css b/public/style.css
index 4a59dc22..f609500d 100644
--- a/public/style.css
+++ b/public/style.css
@@ -1833,8 +1833,34 @@ button.ch-item:hover .ch-icon-btn { opacity: 1; }
   .search-box { width: 95vw; }
   .search-overlay { padding-top: 60px; }
 
-  /* Map controls */
-  .map-controls { width: calc(100vw - 24px); right: 12px; top: 8px; max-height: 200px; font-size: 12px; padding: 10px 12px; }
+  /* Map controls — #1329: drop fixed 200px cap, use accordion sections
+     instead so visible content fits without internal scrolling. Panel can
+     grow to fill available height; max-height bound by viewport so it
+     never escapes the screen. */
+  .map-controls { width: calc(100vw - 24px); right: 12px; top: 8px; max-height: calc(100vh - 80px); font-size: 12px; padding: 10px 12px; }
+  /* On mobile, hide collapsed section bodies (everything inside the
+     fieldset except the legend). The legend remains tappable to expand. */
+  .map-controls fieldset.mc-section.mc-collapsed > *:not(legend) { display: none; }
+  .map-controls fieldset.mc-section > legend.mc-label {
+    cursor: pointer;
+    user-select: none;
+    width: 100%;
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    padding: 6px 0;
+  }
+  /* ▸ / ▾ indicator via ::after so we don't touch markup */
+  .map-controls fieldset.mc-section > legend.mc-label::after {
+    content: '▾';
+    font-size: 10px;
+    color: var(--text-muted);
+    margin-left: 8px;
+    transition: transform 0.15s;
+  }
+  .map-controls fieldset.mc-section.mc-collapsed > legend.mc-label::after {
+    content: '▸';
+  }
   #leaflet-map { z-index: 0; }
   #map-wrap { z-index: 0; }
 
diff --git a/test-issue-1329-map-controls-accordion-e2e.js b/test-issue-1329-map-controls-accordion-e2e.js
new file mode 100644
index 00000000..b5aa91a2
--- /dev/null
+++ b/test-issue-1329-map-controls-accordion-e2e.js
@@ -0,0 +1,177 @@
+/**
+ * E2E (#1329): Map controls panel on mobile must NOT be capped at 200px
+ * with internal scroll. Use accordion sections — one expanded at a time —
+ * so the visible content always fits without scrolling.
+ *
+ * Mobile (375x812):
+ *  - Open Map controls.
+ *  - Panel must have accordion sections (legend acts as toggle, with
+ *    aria-expanded attribute).
+ *  - Default state: at most one section expanded.
+ *  - Panel contents must NOT require internal scroll
+ *    (scrollHeight <= clientHeight + 1).
+ *  - Clicking a different section's legend collapses the previously-open
+ *    section (single-open behavior).
+ *
+ * Desktop (1280x800):
+ *  - Existing layout unchanged: all sections visible by default,
+ *    panel position:absolute, modest width.
+ *
+ * Run: BASE_URL=http://localhost:13581 node test-issue-1329-map-controls-accordion-e2e.js
+ */
+'use strict';
+const { chromium } = require('playwright');
+
+const BASE = process.env.BASE_URL || 'http://localhost:13581';
+
+let passed = 0, failed = 0;
+async function step(name, fn) {
+  try { await fn(); passed++; console.log('  \u2713 ' + name); }
+  catch (e) { failed++; console.error('  \u2717 ' + name + ': ' + e.message); }
+}
+function assert(c, m) { if (!c) throw new Error(m || 'assertion failed'); }
+
+async function run() {
+  const launchOpts = { args: ['--no-sandbox'] };
+  if (process.env.CHROMIUM_PATH) launchOpts.executablePath = process.env.CHROMIUM_PATH;
+  const browser = await chromium.launch(launchOpts);
+
+  // === Mobile: 375x812 ===
+  const ctx = await browser.newContext({ viewport: { width: 375, height: 812 } });
+  const page = await ctx.newPage();
+
+  await page.goto(BASE + '/#/map', { waitUntil: 'load', timeout: 60000 });
+  await page.waitForSelector('#leaflet-map', { timeout: 10000 });
+  await page.waitForSelector('#mapControls', { state: 'attached', timeout: 10000 });
+  await page.waitForTimeout(500);
+
+  // Ensure controls panel is expanded (default is collapsed on mobile).
+  await page.evaluate(() => {
+    const panel = document.getElementById('mapControls');
+    const btn = document.getElementById('mapControlsToggle');
+    if (panel && panel.classList.contains('collapsed')) btn && btn.click();
+  });
+  await page.waitForTimeout(300);
+
+  await step('mobile: at least one accordion section present with aria-expanded', async () => {
+    const data = await page.evaluate(() => {
+      const panel = document.getElementById('mapControls');
+      // Accordion section markers: legend (or button) carrying aria-expanded
+      // inside a .mc-section.mc-accordion (or equivalent) descendant.
+      const toggles = panel.querySelectorAll('.mc-section [aria-expanded], .mc-accordion-toggle[aria-expanded]');
+      const sections = panel.querySelectorAll('.mc-section');
+      return {
+        toggles: toggles.length,
+        sections: sections.length,
+        expandedCount: Array.from(toggles).filter(t => t.getAttribute('aria-expanded') === 'true').length,
+      };
+    });
+    assert(data.toggles >= 1,
+      'expected ≥1 accordion toggle (aria-expanded), got ' + data.toggles +
+      ' (sections=' + data.sections + ')');
+  });
+
+  await step('mobile: at most one section expanded by default', async () => {
+    const data = await page.evaluate(() => {
+      const panel = document.getElementById('mapControls');
+      const toggles = panel.querySelectorAll('.mc-section [aria-expanded], .mc-accordion-toggle[aria-expanded]');
+      return {
+        expandedCount: Array.from(toggles).filter(t => t.getAttribute('aria-expanded') === 'true').length,
+        total: toggles.length,
+      };
+    });
+    assert(data.expandedCount <= 1,
+      'expected ≤1 section expanded by default, got ' + data.expandedCount + '/' + data.total);
+  });
+
+  await step('mobile: panel content does NOT require internal scroll', async () => {
+    const data = await page.evaluate(() => {
+      const panel = document.getElementById('mapControls');
+      return {
+        scrollH: panel.scrollHeight,
+        clientH: panel.clientHeight,
+        overflowY: getComputedStyle(panel).overflowY,
+      };
+    });
+    // The accordion sections should keep content within viewport — when only
+    // one section is expanded, panel must not need to scroll internally.
+    assert(data.scrollH <= data.clientH + 1,
+      'panel must not require internal scroll (scrollH=' + data.scrollH +
+      ' clientH=' + data.clientH + ')');
+  });
+
+  await step('mobile: clicking a 2nd toggle collapses the first (single-open)', async () => {
+    const result = await page.evaluate(() => {
+      const panel = document.getElementById('mapControls');
+      const toggles = Array.from(panel.querySelectorAll('.mc-section [aria-expanded], .mc-accordion-toggle[aria-expanded]'));
+      if (toggles.length < 2) return { skip: true, n: toggles.length };
+      // Find one currently closed and one open; if all closed, open first then click second.
+      let openIdx = toggles.findIndex(t => t.getAttribute('aria-expanded') === 'true');
+      if (openIdx === -1) {
+        toggles[0].click();
+        openIdx = 0;
+      }
+      const otherIdx = openIdx === 0 ? 1 : 0;
+      toggles[otherIdx].click();
+      return {
+        skip: false,
+        firstNow: toggles[openIdx].getAttribute('aria-expanded'),
+        otherNow: toggles[otherIdx].getAttribute('aria-expanded'),
+      };
+    });
+    if (result.skip) {
+      throw new Error('need at least 2 accordion toggles to test single-open (got ' + result.n + ')');
+    }
+    assert(result.otherNow === 'true',
+      'second toggle should be open after click, got ' + result.otherNow);
+    assert(result.firstNow === 'false',
+      'first toggle should auto-close (single-open), got ' + result.firstNow);
+  });
+
+  await ctx.close();
+
+  // === Desktop: 1280x800 ===
+  const ctx2 = await browser.newContext({ viewport: { width: 1280, height: 800 } });
+  const p2 = await ctx2.newPage();
+  await p2.goto(BASE + '/#/map', { waitUntil: 'load', timeout: 60000 });
+  await p2.waitForSelector('#mapControls', { state: 'attached', timeout: 10000 });
+  await p2.waitForTimeout(300);
+
+  await step('desktop (1280px): panel position:absolute, all section contents visible', async () => {
+    const data = await p2.evaluate(() => {
+      const panel = document.getElementById('mapControls');
+      const cs = getComputedStyle(panel);
+      const rect = panel.getBoundingClientRect();
+      // Check that section content (e.g., labels) is visible on desktop.
+      const allInputs = panel.querySelectorAll('input[type=checkbox], select, button');
+      let visible = 0;
+      allInputs.forEach(el => {
+        const r = el.getBoundingClientRect();
+        if (r.width > 0 && r.height > 0) visible++;
+      });
+      return {
+        position: cs.position,
+        width: Math.round(rect.width),
+        vw: window.innerWidth,
+        visibleControls: visible,
+        totalControls: allInputs.length,
+      };
+    });
+    assert(data.position === 'absolute',
+      'desktop panel must be position:absolute, got ' + data.position);
+    assert(data.width < data.vw * 0.5,
+      'desktop panel must be <50% viewport width, got ' + data.width + '/' + data.vw);
+    // All (or nearly all) controls should be visible on desktop — accordion
+    // collapse must NOT apply at desktop sizes.
+    assert(data.visibleControls >= data.totalControls - 2,
+      'desktop must show all controls (got ' + data.visibleControls + '/' + data.totalControls + ')');
+  });
+
+  await browser.close();
+
+  console.log('\n' + passed + '/' + (passed + failed) + ' tests passed' +
+              (failed ? ', ' + failed + ' failed' : ''));
+  process.exit(failed > 0 ? 1 : 0);
+}
+
+run().catch(err => { console.error('Fatal:', err); process.exit(1); });