change app name, add route calculator

lib/components/login/login.dart

@@ -19,12 +19,22 @@ class LoginScreen extends StatelessWidget {
               Text.rich(
                 TextSpan(
                   children: [
-                    TextSpan(text: "Mile"),
+                    TextSpan(
+                      text: "Mile",
+                      style: TextStyle(
+                        color: Theme.of(context).textTheme.bodyLarge?.color,
+                      ),
+                    ),
                     TextSpan(
                       text: "O",
                       style: TextStyle(color: Colors.red),
                     ),
-                    TextSpan(text: "graph"),
+                    TextSpan(
+                      text: "graph",
+                      style: TextStyle(
+                        color: Theme.of(context).textTheme.bodyLarge?.color,
+                      ),
+                    ),
                   ],
                   style: TextStyle(
                     decoration: TextDecoration.none,