The suite has every control you will ever need for a web app. To get familiar with all it can do, they have numerous demo apps so you can see it in action and see if it will work for you.
They then have some 17 themes and one of them is sure to be of your liking, whether you like a light or dark them, or something in between.
The documentation is then available which goes into detail every aspect of the control so you can customize it to your needs. And if you need help in getting going, Syncfusion support stands ready to help you out with answer and a sample app.
In several cases, I have asked for something they do not yet support, and they have come through with the requested modifications.
I have been creating web apps with Syncfusion for over 4 years now, and I would much rather use an existing library then to roll-my-own. Syncfusion fits that bill perfectly.
Using a control suite save literally years of time over trying to write your own, or searching the web for a widget. Syncfusion controls work well together and is a complete, affordable solution.