diff --git a/templates/index.html b/templates/index.html
index fe7fb8b..47c64d2 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -672,7 +672,7 @@
             font-weight: 500;
             padding: 2px 7px;
             white-space: nowrap;
-            pointer-events: none;
+            cursor: pointer;
         }
 
         /* Custom circular pin that reflects the POI type */
@@ -1064,14 +1064,12 @@
 
         // Build a viewbox from the currently visible map area so
         // results are restricted to what the user can see.
-        const mb = map.getBounds();
-
-        const viewbox = [
-            mb.west,
-            mb.north,
-            mb.east,
-            mb.south
-        ].join(",");
+        //
+        // Only send a viewbox once the map has loaded AND the
+        // bounds are geometrically valid. Otherwise we fall back
+        // straight to a global search (see below).
+        const viewbox =
+            getValidViewbox();
 
 
         let data =
@@ -1293,6 +1291,133 @@
     }
 
 
+    /* =========================================================
+       VIEWBOX HELPER
+       ========================================================= */
+
+    /*
+     * How far beyond the visible map area we extend the
+     * search box, in kilometres. This keeps results from
+     * being cut off at the screen edges.
+     */
+    const VIEWBOX_PADDING_KM = 5;
+
+
+    /*
+     * Convert a distance in metres to degrees of longitude
+     * at a given latitude.
+     */
+    function metersToLonDegrees(meters, lat) {
+
+        const rad =
+            lat * Math.PI / 180;
+
+        return meters /
+            (111320 * Math.cos(rad));
+    }
+
+
+    /*
+     * Convert a distance in metres to degrees of latitude.
+     */
+    function metersToLatDegrees(meters) {
+
+        return meters / 110574;
+    }
+
+
+    /*
+     * Return a "west,north,east,south" string for the
+     * currently visible map area, expanded by
+     * VIEWBOX_PADDING_KM on every side, or null if the map
+     * isn't ready yet or the bounds aren't usable. A null
+     * value makes the caller perform an unrestricted
+     * (global) search instead.
+     */
+    function getValidViewbox() {
+
+        if (!map.loaded())
+            return null;
+
+
+        const mb = map.getBounds();
+
+        let west =
+            mb.getWest();
+
+        let north =
+            mb.getNorth();
+
+        let east =
+            mb.getEast();
+
+        let south =
+            mb.getSouth();
+
+
+        /*
+         * Reject NaN / infinite values and inverted boxes.
+         */
+        if (
+            !isFinite(west) ||
+            !isFinite(north) ||
+            !isFinite(east) ||
+            !isFinite(south)
+        )
+            return null;
+
+
+        if (
+            east <= west ||
+            north <= south
+        )
+            return null;
+
+
+        /*
+         * Expand the box by the padding distance so that
+         * places just outside the viewport are still found.
+         */
+        const padMeters =
+            VIEWBOX_PADDING_KM * 1000;
+
+        const midLat =
+            (north + south) / 2;
+
+        const dLat =
+            metersToLatDegrees(padMeters);
+
+        const dLon =
+            metersToLonDegrees(
+                padMeters,
+                midLat
+            );
+
+
+        west -= dLon;
+        east += dLon;
+        north += dLat;
+        south -= dLat;
+
+
+        /*
+         * Clamp to valid geographic ranges after expansion.
+         */
+        north = Math.min(north, 90);
+        south = Math.max(south, -90);
+        west = Math.max(west, -180);
+        east = Math.min(east, 180);
+
+
+        return [
+            west,
+            north,
+            east,
+            south
+        ].join(",");
+    }
+
+
     /* =========================================================
        PERFORM SEARCH
        ========================================================= */