The hardcoded Color(0xFFE8F0F7) caused visibility issues. It’s better to rely on the app’s theme or use an official brand color of Khalti(Color(0xFFDC0019)) with foregroundColor: Colors.white.

[mrdeephang]

//uses khalti brand color
title: const Text(s_payWithKhalti),
backgroundColor: Color(0xFFDC0019),
foregroundColor: Colors.white,
actions: [
IconButton(
onPressed: _reload,
icon: const Icon(Icons.refresh),
)
],
elevation: 4,
),

//uses your app brand Color
title: const Text(s_payWithKhalti),
actions: [
IconButton(
onPressed: _reload,
icon: const Icon(Icons.refresh),
)
],
elevation: 4,
),
Use the app’s brand color via AppBarTheme defined in MaterialApp instead of hardcoding colors.
appBarTheme: const AppBarTheme(
centerTitle: true,
foregroundColor: Colors.white,
backgroundColor: primaryColor,
elevation: 0,
),