some more ui on overview

lib/overview.dart

@@ -8,26 +8,37 @@ class Overview extends StatelessWidget {
       appBar: AppBar(title: const Text('Mobile Event Log')),
       body: Center(
           child: Column(
-            mainAxisAlignment: MainAxisAlignment.spaceAround,
+            mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+            crossAxisAlignment: CrossAxisAlignment.stretch,
             children: <Widget>[
-              ElevatedButton(
-                child: const Text('Add Event'),
-                onPressed: () {
-                  Navigator.pushNamed(context, '/second');
-                },
+              const SizedBox(height: 10),
+              Expanded(
+                child: ElevatedButton(
+                  child: const Text('Add Event', style: TextStyle(fontSize: 22)),
+                  onPressed: () {
+                    Navigator.pushNamed(context, '/second');
+                  },
+                ),
               ),
-              ElevatedButton(
-                child: const Text('View Added Events'),
-                onPressed: () {
-                  Navigator.pushNamed(context, '/third');
-                },
+              const SizedBox(height: 10),
+              Expanded(
+                child: ElevatedButton(
+                  child: const Text('View Added Events', style: TextStyle(fontSize: 22)),
+                  onPressed: () {
+                    Navigator.pushNamed(context, '/third');
+                  },
+                ),
               ),
-              ElevatedButton(
-                child: const Text('Configuration'),
-                onPressed: () {
-                  Navigator.pushNamed(context, '/forth');
-                },
+              const SizedBox(height: 10),
+              Expanded(
+                child: ElevatedButton(
+                  child: const Text('Configuration', style: TextStyle(fontSize: 22)),
+                  onPressed: () {
+                    Navigator.pushNamed(context, '/forth');
+                  },
+                ),
               ),
+              const SizedBox(height: 10),
             ],
           )),
     );