Customize navigation bar on Hotwire Native iOS

AppDelegate.swift

import UIKit

@main
class AppDelegate: UIResponder, UIApplicationDelegate {
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
        let appearance = UINavigationBarAppearance()
        appearance.configureWithOpaqueBackground()
        appearance.backgroundColor = .systemGreen
        /// https://developer.apple.com/documentation/uikit/uinavigationbarappearance
        UINavigationBar.appearance().scrollEdgeAppearance = appearance

        return true
    }
}