Update activity rendering and styles in Programs component

- Added conditional rendering for activity time to prevent displaying empty values.
- Adjusted styles for time text and activity title to improve layout consistency.

app/(tabs)/programs.tsx

@@ -108,7 +108,7 @@ export default function Programs() {
             <View key={index}>
               <View style={styles.activityCard}>
                 <View style={styles.timeContainer}>
-                  <Text style={styles.timeText}>{activity.time}</Text>
+                  {activity.time && <Text style={styles.timeText}>{activity.time}</Text>}
                   <Text style={styles.activityTitle}>{activity.title}</Text>
                   <Text style={styles.activityDescription}>{activity.description}</Text>
                 </View>
@@ -196,12 +196,13 @@ const styles = StyleSheet.create({
   timeText: {
     color: 'gray',
     fontSize: 14,
+    marginBottom: 4,
   },
   activityTitle: {
     color: 'white',
     fontSize: 20,
     fontWeight: 'bold',
-    marginVertical: 4,
+    marginBottom: 4,
   },
   activityDescription: {
     color: 'gray',