1. To inspect your code on the application of the decisions do not support UC Browser (you can check this here - caniuse.com/)
2. Remove unsupported decisions from the code, or you can configure the stub.
Example browser does not support css custom properties (css variables), write this code:
In the end, the browser does not support custom properties will simply ignore the second width.
3. If you remove the impossible - looking for a js-politely. It is the realization of properties on js in unsupported browsers. But there may also be difficulties because the browser support js too may not be complete.