diff --git a/web/fleet-core.js b/web/fleet-core.js
index d949e4a..3dce904 100644
--- a/web/fleet-core.js
+++ b/web/fleet-core.js
@@ -602,81 +602,205 @@ export function applyClientFilter(map, { costCentres = [], cities = [] } = {}) {
 
 /* ---------- trip panel ---------- */
 
-const TRIP_PATH_SOURCE = 'trip-path-source';
-const TRIP_MARKER_SOURCE = 'trip-marker-source';
-const TRIP_PATH_LAYER = 'trip-path-line';
-const TRIP_MARKER_LAYER = 'trip-marker-dot';
 const TRIP_ANIM_MS = 10000;
+// Single-trip animation overlays (used in single-vehicle mode only).
+const TRIP_PATH_SOURCE   = 'trip-path-source';
+const TRIP_MARKER_SOURCE = 'trip-marker-source';
+const TRIP_PATH_LAYER    = 'trip-path-line';
+const TRIP_MARKER_LAYER  = 'trip-marker-dot';
+
+// Distinct palette for selected vehicles in multi-mode (kept separate from
+// cost-centre tints so a multi-comparison reads cleanly even when picked
+// vehicles share a cost centre).
+const SELECTION_PALETTE = [
+  '#10b981',  // emerald (single-mode default)
+  '#3b82f6',  // blue
+  '#ef4444',  // red
+  '#f59e0b',  // amber
+  '#a855f7',  // purple
+  '#06b6d4',  // cyan
+  '#ec4899',  // pink
+  '#84cc16',  // lime
+];
 
 let _tripAnimRAF = null;
-let _tripState = { vehicleId: null, date: null, payload: null };
+// vehicleId → { plate, driver, color, payload | null }
+const _selection = new Map();
+let _currentDate = null;
+
+function _nextColor() {
+  const used = new Set([..._selection.values()].map(v => v.color));
+  for (const c of SELECTION_PALETTE) {
+    if (!used.has(c)) return c;
+  }
+  return SELECTION_PALETTE[_selection.size % SELECTION_PALETTE.length];
+}
 
 export function initTripPanel(map, panelRoot) {
   const els = {
-    plate:   panelRoot.querySelector('#trip-plate'),
-    driver:  panelRoot.querySelector('#trip-driver'),
-    date:    panelRoot.querySelector('#trip-date'),
-    csv:     panelRoot.querySelector('#trip-csv'),
-    totals:  panelRoot.querySelector('#trip-totals'),
-    list:    panelRoot.querySelector('#trip-list'),
-    close:   panelRoot.querySelector('#trip-close'),
+    plate:  panelRoot.querySelector('#trip-plate'),
+    driver: panelRoot.querySelector('#trip-driver'),
+    date:   panelRoot.querySelector('#trip-date'),
+    csv:    panelRoot.querySelector('#trip-csv'),
+    totals: panelRoot.querySelector('#trip-totals'),
+    list:   panelRoot.querySelector('#trip-list'),
+    close:  panelRoot.querySelector('#trip-close'),
   };
 
   els.close.addEventListener('click', () => _closeTripPanel(map, panelRoot, els));
-  els.date.addEventListener('change', () => {
-    if (_tripState.vehicleId) {
-      _loadTrips(map, panelRoot, els, _tripState.vehicleId, els.date.value);
+  els.date.addEventListener('change', async () => {
+    _currentDate = els.date.value;
+    // Re-fetch every currently-selected vehicle for the new date.
+    for (const vid of [..._selection.keys()]) {
+      await _fetchAndDraw(map, vid);
     }
+    _renderDock(map, els);
   });
   els.csv.addEventListener('click', () => {
-    if (_tripState.vehicleId) _downloadTripsCsv(_tripState.vehicleId, els.date.value);
+    for (const vid of _selection.keys()) {
+      _downloadTripsCsv(vid, _currentDate);
+    }
   });
 
-  const layers = ['vehicles-circle', 'vehicles-arrow', 'vehicles-label'];
-  map.on('click', (e) => {
-    const features = map.queryRenderedFeatures(e.point, { layers });
+  const hoverLayers = ['vehicles-circle', 'vehicles-arrow', 'vehicles-label'];
+  map.on('click', async (e) => {
+    const features = map.queryRenderedFeatures(e.point, { layers: hoverLayers });
     if (!features || features.length === 0) return;
     const f = features[0];
     const vid = f.properties.vehicle_id;
     if (!vid) return;
-    els.plate.textContent = f.properties.plate || `Vehicle ${vid}`;
-    els.driver.textContent = f.properties.driver_name || '';
+    const plate  = f.properties.plate || `Vehicle ${vid}`;
+    const driver = f.properties.driver_name || '';
+    const multi  = e.originalEvent.metaKey || e.originalEvent.ctrlKey || e.originalEvent.shiftKey;
+
     if (!els.date.value) els.date.value = _todayEat();
+    _currentDate = els.date.value;
     panelRoot.classList.add('open');
     panelRoot.setAttribute('aria-hidden', 'false');
-    _loadTrips(map, panelRoot, els, vid, els.date.value);
+
+    if (multi) {
+      if (_selection.has(vid)) {
+        _removeVehicle(map, vid);
+        _renderDock(map, els);
+      } else {
+        _addVehicle(vid, plate, driver);
+        await _fetchAndDraw(map, vid);
+        _renderDock(map, els);
+      }
+    } else {
+      // Plain click → reset to this single vehicle
+      _clearSelection(map);
+      _addVehicle(vid, plate, driver);
+      await _fetchAndDraw(map, vid);
+      _renderDock(map, els);
+    }
   });
 }
 
-async function _loadTrips(map, panelRoot, els, vehicleId, dateStr) {
-  _tripState.vehicleId = vehicleId;
-  _tripState.date = dateStr;
-  _tripState.payload = null;
-  _cancelTripAnim();
-  _clearTripLayers(map);
-  els.totals.innerHTML = 'Loading…';
-  els.list.innerHTML = '';
-  try {
-    const payload = await apiFetch(
-      `/api/views/vehicle/${vehicleId}/trips`,
-      { params: { date: dateStr } },
-    );
-    _tripState.payload = payload;
-    _renderTripPanel(map, els, payload);
-  } catch (err) {
-    els.totals.innerHTML = `<span style="color:var(--bad)">${_esc(err.message || err)}</span>`;
-  }
+function _addVehicle(vid, plate, driver) {
+  _selection.set(vid, { plate, driver, color: _nextColor(), payload: null });
 }
 
-function _renderTripPanel(map, els, payload) {
+function _removeVehicle(map, vid) {
+  _clearVehicleLayers(map, vid);
+  _selection.delete(vid);
+}
+
+function _clearSelection(map) {
+  for (const vid of [..._selection.keys()]) _clearVehicleLayers(map, vid);
+  _selection.clear();
+  _cancelTripAnim();
+  _clearSingleTripLayers(map);
+}
+
+async function _fetchAndDraw(map, vid) {
+  const entry = _selection.get(vid);
+  if (!entry) return;
+  try {
+    entry.payload = await apiFetch(
+      `/api/views/vehicle/${vid}/trips`,
+      { params: { date: _currentDate } },
+    );
+  } catch (err) {
+    entry.payload = { error: err.message || String(err), trips: [] };
+    return;
+  }
+  // Draw this vehicle's all-day routes as a static overlay.
+  _drawVehicleDayPaths(map, vid, entry.payload, entry.color);
+}
+
+function _drawVehicleDayPaths(map, vid, payload, color) {
+  _clearVehicleLayers(map, vid);
+  const trips = (payload.trips || []).filter(t => t.path && t.path.coordinates);
+  if (trips.length === 0) return;
+  const features = trips.map(t => ({
+    type: 'Feature',
+    geometry: t.path,
+    properties: { trip_id: t.trip_id, vehicle_id: vid },
+  }));
+  const srcId = `vroute-${vid}`;
+  const layerId = `vroute-line-${vid}`;
+  map.addSource(srcId, {
+    type: 'geojson',
+    data: { type: 'FeatureCollection', features },
+  });
+  map.addLayer({
+    id: layerId,
+    type: 'line',
+    source: srcId,
+    layout: { 'line-join': 'round', 'line-cap': 'round' },
+    paint: {
+      'line-color': color,
+      'line-width': ['interpolate', ['linear'], ['zoom'], 8, 1.5, 14, 3, 17, 5],
+      'line-opacity': 0.85,
+    },
+  });
+}
+
+function _clearVehicleLayers(map, vid) {
+  const layerId = `vroute-line-${vid}`;
+  const srcId   = `vroute-${vid}`;
+  if (map.getLayer(layerId)) map.removeLayer(layerId);
+  if (map.getSource(srcId)) map.removeSource(srcId);
+}
+
+function _renderDock(map, els) {
+  if (_selection.size === 0) {
+    els.plate.textContent = '—';
+    els.driver.textContent = '';
+    els.totals.innerHTML = 'Click a vehicle to see its trips.';
+    els.list.innerHTML = '';
+    return;
+  }
+
+  if (_selection.size === 1) {
+    _renderSingle(map, els);
+  } else {
+    _renderMulti(map, els);
+  }
+  // Fit map to union of all selected vehicles' route bounds
+  _fitSelectionBounds(map);
+}
+
+function _renderSingle(map, els) {
+  const [[vid, entry]] = _selection;
+  els.plate.textContent  = entry.plate;
+  els.driver.textContent = entry.driver;
+  if (!entry.payload || entry.payload.error) {
+    els.totals.innerHTML = entry.payload?.error
+      ? `<span style="color:var(--bad)">${_esc(entry.payload.error)}</span>`
+      : 'Loading…';
+    els.list.innerHTML = '';
+    return;
+  }
+  const payload = entry.payload;
   const t = payload.totals || {};
   const q = payload.data_quality || {};
-  const reportingTime = payload.reporting_time
-    ? _formatTimeOnly(payload.reporting_time) : '—';
+  const rep = payload.reporting_time ? _formatTimeOnly(payload.reporting_time) : '—';
   els.totals.innerHTML = `
-    <div>Reporting <strong>${_esc(reportingTime)}</strong> · <strong>${t.trip_count ?? 0}</strong> trips · <strong>${_fmtNum(t.distance_km, 1)}</strong> km</div>
+    <div>Reporting <strong>${_esc(rep)}</strong> · <strong>${t.trip_count ?? 0}</strong> trips · <strong>${_fmtNum(t.distance_km, 1)}</strong> km</div>
     <div>drive ${_fmtNum(t.driving_min, 0)}m · idle ${_fmtNum(t.idling_min, 0)}m · stop ${_fmtNum(t.stopped_min, 0)}m</div>
-    <div class="trip-quality">${q.fix_count ?? 0} fixes · ACC ${q.has_acc_data ? 'on' : 'off'}</div>
+    <div class="trip-quality">${q.fix_count ?? 0} fixes · ACC ${q.has_acc_data ? 'on' : 'off'} · ⌘-click to compare</div>
   `;
 
   const trips = payload.trips || [];
@@ -712,6 +836,101 @@ function _renderTripPanel(map, els, payload) {
   }
 }
 
+function _renderMulti(map, els) {
+  // Aggregate totals across all loaded payloads.
+  let tripCount = 0, distance = 0, drive = 0, idle = 0, stop = 0;
+  for (const { payload } of _selection.values()) {
+    if (!payload || payload.error) continue;
+    const t = payload.totals || {};
+    tripCount += t.trip_count ?? 0;
+    distance  += Number(t.distance_km ?? 0);
+    drive     += Number(t.driving_min ?? 0);
+    idle      += Number(t.idling_min ?? 0);
+    stop      += Number(t.stopped_min ?? 0);
+  }
+
+  els.plate.textContent  = `${_selection.size} vehicles`;
+  els.driver.textContent = '⌘-click another vehicle to add / remove';
+  els.totals.innerHTML = `
+    <div><strong>${tripCount}</strong> trips · <strong>${_fmtNum(distance, 1)}</strong> km</div>
+    <div>drive ${_fmtNum(drive, 0)}m · idle ${_fmtNum(idle, 0)}m · stop ${_fmtNum(stop, 0)}m</div>
+  `;
+
+  // One compact row per vehicle, in selection order.
+  const rows = [..._selection.entries()].map(([vid, entry]) => {
+    const t = entry.payload?.totals || {};
+    return `
+      <div class="trip-card trip-vehicle-row" data-vehicle-id="${vid}" style="border-left-color:${_esc(entry.color)};border-left-width:4px;border-left-style:solid">
+        <div class="trip-card-top">
+          <span>${_esc(entry.plate)}</span>
+          <button class="trip-vehicle-remove" data-remove="${vid}" aria-label="Remove">✕</button>
+        </div>
+        <div class="trip-card-times">${_esc(entry.driver || '—')}</div>
+        <div class="trip-card-meta">
+          <span>${t.trip_count ?? 0} trips</span>
+          <span>${_fmtNum(t.distance_km, 1)} km</span>
+          <span>${_fmtNum(t.driving_min, 0)}m drive</span>
+        </div>
+      </div>
+    `;
+  }).join('');
+  els.list.innerHTML = rows;
+
+  for (const btn of els.list.querySelectorAll('.trip-vehicle-remove')) {
+    btn.addEventListener('click', (ev) => {
+      ev.stopPropagation();
+      const vid = Number(btn.dataset.remove);
+      _removeVehicle(map, vid);
+      _renderDock(map, els);
+    });
+  }
+  for (const row of els.list.querySelectorAll('.trip-vehicle-row')) {
+    row.addEventListener('click', () => {
+      const vid = Number(row.dataset.vehicleId);
+      _fitVehicleBounds(map, vid);
+    });
+  }
+}
+
+function _fitSelectionBounds(map) {
+  // eslint-disable-next-line no-undef
+  let bounds = null;
+  for (const { payload } of _selection.values()) {
+    if (!payload || !payload.trips) continue;
+    for (const trip of payload.trips) {
+      const coords = trip.path?.coordinates;
+      if (!coords || coords.length < 1) continue;
+      for (const c of coords) {
+        // eslint-disable-next-line no-undef
+        if (!bounds) bounds = new maplibregl.LngLatBounds(c, c);
+        else bounds.extend(c);
+      }
+    }
+  }
+  if (bounds) {
+    map.fitBounds(bounds, { padding: { top: 60, right: 60, bottom: 360, left: 60 }, duration: 600, maxZoom: 14 });
+  }
+}
+
+function _fitVehicleBounds(map, vid) {
+  const entry = _selection.get(vid);
+  if (!entry?.payload?.trips) return;
+  // eslint-disable-next-line no-undef
+  let bounds = null;
+  for (const trip of entry.payload.trips) {
+    const coords = trip.path?.coordinates;
+    if (!coords) continue;
+    for (const c of coords) {
+      // eslint-disable-next-line no-undef
+      if (!bounds) bounds = new maplibregl.LngLatBounds(c, c);
+      else bounds.extend(c);
+    }
+  }
+  if (bounds) {
+    map.fitBounds(bounds, { padding: { top: 60, right: 60, bottom: 360, left: 60 }, duration: 600, maxZoom: 14 });
+  }
+}
+
 function _reasonClass(r) {
   if (r === 'work_stop')  return 'work-stop';
   if (r === 'nofix_stop') return 'nofix-stop';
@@ -729,7 +948,7 @@ function _reasonLabel(r) {
 
 function _showAndAnimateTrip(map, trip) {
   _cancelTripAnim();
-  _clearTripLayers(map);
+  _clearSingleTripLayers(map);
   if (!trip.path || !trip.path.coordinates || trip.path.coordinates.length < 2) return;
   const coords = trip.path.coordinates;
 
@@ -820,7 +1039,7 @@ function _cancelTripAnim() {
   }
 }
 
-function _clearTripLayers(map) {
+function _clearSingleTripLayers(map) {
   for (const id of [TRIP_MARKER_LAYER, TRIP_PATH_LAYER]) {
     if (map.getLayer(id)) map.removeLayer(id);
   }
@@ -830,13 +1049,13 @@ function _clearTripLayers(map) {
 }
 
 function _closeTripPanel(map, panelRoot, els) {
-  _cancelTripAnim();
-  _clearTripLayers(map);
+  _clearSelection(map);
   panelRoot.classList.remove('open');
   panelRoot.setAttribute('aria-hidden', 'true');
   els.totals.innerHTML = 'Click a vehicle to see its trips.';
   els.list.innerHTML = '';
-  _tripState = { vehicleId: null, date: null, payload: null };
+  els.plate.textContent = '—';
+  els.driver.textContent = '';
 }
 
 function _todayEat() {
diff --git a/web/index-live.html b/web/index-live.html
index 07a383f..c790495 100644
--- a/web/index-live.html
+++ b/web/index-live.html
@@ -182,6 +182,12 @@
     .trip-card-reason.work-stop  { color: var(--accent); }
     .trip-card-reason.nofix-stop { color: var(--warn); }
     .trip-card-reason.long-gap   { color: var(--bad); }
+    .trip-vehicle-row { min-width: 200px; }
+    .trip-vehicle-remove {
+      background: transparent; color: var(--muted); border: 0;
+      font-size: 14px; cursor: pointer; padding: 0 4px; line-height: 1;
+    }
+    .trip-vehicle-remove:hover { color: var(--bad); }
   </style>
 </head>
 <body>