polygon - Changing categorized style color simultaneously in QGIS

I work with this polygon: and i need that all features will be with border line only without fil colors. I seek for a way to do it simultaneously to all the categorized features, and not treat every

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polygon - Same symbology and color for all attributes of layer in

polygon - Same symbology and color for all attributes of layer in

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QGIS data visualisation. This short blog outlines how to create

polygon - Changing categorized style color simultaneously in QGIS

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4.3. Lesson: Classification — QGIS Documentation documentation