I'm flexible on what framework we use, but the REQUIREMENTS are: 1. Must be well-establihed, well-supported, stable and LONG TERM VIABLE.
2. Must not require any runtime language other than JavaScript. 3. Flexible layout -- I want it to seamlessly reflow properly on small/mobile devices. 4. License compatible with our existing code base. I have ABSOLUTELY NO INTEREST in supporting outdated browsers. Right out of the gate I'm thinking the minimum required browsers will be: IE 9, Edge 13, Firefox 44, Chrome 47, Safari 9, Opera 36, iOS Safari 8.4, Android browser 4.3, Android Chrome 49. This gives us reasonable HTML5 support, and also support for data: URI's, which are something I've come to love recently.