You have the option of using Dart web with a higher-level web app framework. Several web apps at Google (including the Google Ads front end formerly known as AdWords) are built using AngularDart. Many apps that support both web and mobile are built using Flutter and Flutter web support. AngularDart, Flutter web support, and other web app frameworks for Dart are powered by the Dart web platform.
Flutter Gallery, running in a web browser