Nested CSS is not supported in ThemeBuilder's externalStyles.

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Unplanned

Last Updated: 06 Feb 2026 08:44 by ADMIN

Jeff

Created on: 05 Feb 2026 15:00

Type: Feature Request

Nested CSS is not supported in ThemeBuilder's externalStyles.

Modern CSS supports nesting. This would seem to be a good way to cut down on the overall size of the export file.

Are there any plans to update ThemeBuilder to support CSS nesting?

Ex.

Instead of this...

.fk-daterangepicker .k-input-suffix,
.fk-daterangepicker .k-input-prefix {
  cursor: pointer;
  &:hover {
  background-color: var(--kendo-color-primary-subtle-hover);
  }
}

I have to define this set of styles like this...

.fk-daterangepicker .k-input-suffix,
.fk-daterangepicker .k-input-prefix {
  cursor: pointer;
}
.fk-daterangepicker .k-input-suffix:hover,
.fk-daterangepicker .k-input-prefix:hover {
  background-color: var(--kendo-color-primary-subtle-hover);
}

Repeating this pattern over an entire design system adds a lot of extra text...

1 comment

ADMIN

Nick Iliev

Posted on: 06 Feb 2026 08:44

Hello Jeff,

I can confirm that nested CSS is currently not supported in ThemeBuilder's "External Styles" feature.

I am submitting this as a feature request for the community to vote on and provide feedback. Based on the community's votes, the team will prioritize the most requested features for future updates.

Regards,
Nick Iliev
Progress Telerik

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