We tried to use the official LESS release and submitted a pull request for the linear-gradient function, but it was not taken into account. I later closed the request after we added other changes. Unfortunately the linear-gradient issue is not as easy as just making another mixin. The linear-gradient function we added supports multiple gradients with any number of color stops while supporting the W3C and the old WebKit gradient syntax, and also generates multiple properties while using the same initial property - something not supported by the official LESS parser as functions don't have access to their calling properties.
However, since the @import/@requre issue can be solved with some changes to our internal build system, we can at least do that and upgrade to 1.3, then you'll be able to use the official LESS and dotLess releases to build the Kendo UI Web less files. We hope that we can do these changes for the Q3 release later this year.
For Kendo UI Mobile we can try again to push our changes upstream, but we can't promise that they will be accepted.
All the best,
the Telerik team
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