At a specific zoom level, the transparency of the features in the Mapbox GL JS map will become 100%, instead of the 50% transparency I set

mapbox-gl-js3.2.0 + Vue2.6.11
When the map is scaled to level 11, the transparency of the vector graphics will not be the same as the transparency I set, but will become 100%. The three parameters output by the console are map. getZoom(), map. getPaintProperty (‘mvtBase ‘,’ fill space ‘), and map. getPaintProperty (‘mvtBase’, ‘fill color’)
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I hope the transparency of features can be displayed normally