Lots of improvements

frontend/src/components/map/TravelTimeCard.tsx

@@ -26,11 +26,13 @@ interface TravelTimeCardProps {
   slug: string;
   label: string;
   timeRange: [number, number] | null;
+  useBest: boolean;
   dataRange: [number, number] | null;
   isPinned: boolean;
   onTogglePin: () => void;
   onSetDestination: (slug: string, label: string) => void;
   onTimeRangeChange: (range: [number, number]) => void;
+  onToggleBest: () => void;
   onRemove: () => void;
 }
 
@@ -39,11 +41,13 @@ export function TravelTimeCard({
   slug,
   label,
   timeRange,
+  useBest,
   dataRange,
   isPinned,
   onTogglePin,
   onSetDestination,
   onTimeRangeChange,
+  onToggleBest,
   onRemove,
 }: TravelTimeCardProps) {
   const search = useLocationSearch(mode);
@@ -119,6 +123,24 @@ export function TravelTimeCard({
         )}
       </div>
 
+      {/* Best-case toggle — transit only, shown when destination is set */}
+      {slug && mode === 'transit' && (
+        <label className="flex items-center gap-1.5 cursor-pointer">
+          <input
+            type="checkbox"
+            checked={useBest}
+            onChange={onToggleBest}
+            className="accent-teal-600 rounded"
+          />
+          <span className="text-xs text-warm-600 dark:text-warm-300">
+            Best case
+          </span>
+          <span className="text-[10px] text-warm-400 dark:text-warm-500">
+            (optimal departure)
+          </span>
+        </label>
+      )}
+
       {/* Time range slider — only show when we have data */}
       {slug && dataRange && (
         <div>