Prior to CSS3 and HTML5, web development was a wild affair of browser incompatibility and divergent standards. Developers rejoiced with their introduction, and these standards ushered in a new era of web development.
Both CSS3 and HTML5 have industry-wide support and work in all major browsers across a wide-range of devices. Excellent frameworks have been created around them, such as jQuery, Bootstrap, Angular and React, to enrich UI development.
The undeniable sophistication of CSS3 and HTML5 compelled up to make sure our design was heavily influenced by them. This marriage of WPF and the modern web worked out beautifully.
If you are familiar with .NET UI development, you will be happy to hear the classes and types and patterns you have grown accustomed to are front and center of the design, as the Frogui class diagram shows.
Web developments will appreciate a no-compromise design that gives them access to familiar features such as web measurement units (discussed in Features), grids and flexboxes.