Why is my connection to the api endpoint failing?

Question

I can connect to this api endpoint in the browser just fine.

This is my Dart code:

class Data with ChangeNotifier {
  Future<void> getQuestions() async {
    var response = await http.get(
      Uri.parse('https://arkiteki.co/api/v1/questions'),
    );
  }
}

This is the error that I get: _ClientSocketException (Connection failed)

Why is this happening?