Ionic Framework and Mobile Web

The problem: build a somewhat complex form that submits data to MySQL+PHP back-end. Requirements include:

• Accessible from browsers running on mobiles, tablets and desktops
• Must be completely platform independent; works well on Edge, Safari, Chrome, and other modern browsers.
• Must be implemented so that in the future, native versions can be implemented using the same code-base.

Based on my research, Ionic seems to be the best fit. However, I don't see anything about using Ionic for web-apps on their official website.

Questions:

1. Can Ionic be used to meet the above requirements? If yes, what is the best way to use Ionic for web-apps? Is there an official guideline from Ionic for this?
2. How else would you go about meeting the above requirements if not using Ionic?

Thanks.