feat: replace dot with left border line on park rows/cards

Open parks get a colored left border (green/amber/blue) instead of a dot.
Region headers lose their accent line; distinguished by "— REGION —" format
with higher-contrast text instead.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

components/MobileCardList.tsx

@@ -24,25 +24,17 @@ export function MobileCardList({ grouped, weekDates, data, today, rideCounts, co
           <div style={{
             display: "flex",
             alignItems: "center",
-            gap: 10,
             marginBottom: 10,
             paddingLeft: 2,
           }}>
-            <div style={{
-              width: 3,
-              height: 14,
-              borderRadius: 2,
-              background: "var(--color-region-accent)",
-              flexShrink: 0,
-            }} />
             <span style={{
-              fontSize: "0.65rem",
+              fontSize: "0.6rem",
               fontWeight: 700,
-              letterSpacing: "0.1em",
+              letterSpacing: "0.14em",
               textTransform: "uppercase",
-              color: "var(--color-text-muted)",
+              color: "var(--color-text-secondary)",
             }}>
-              {region}
+              — {region} —
             </span>
           </div>
 
@@ -60,7 +52,7 @@ export function MobileCardList({ grouped, weekDates, data, today, rideCounts, co
                 isOpen={openParkIds?.includes(park.id)}
                 isClosing={closingParkIds?.includes(park.id)}
                 isWeatherDelay={weatherDelayParkIds?.includes(park.id)}
-              />
+                />
             ))}
           </div>
         </div>