ApplyVisualState(estado) re-resolve o tema e pinta o Background (RoundedBox/Box) com fill+borda do estado: Normal=BgNormal/BorderNormal, Hovered=BgHover/BorderHover, Pressed=BgPressed/BorderHover, Disabled=BgDisabled/BorderNormal. Overrides do UCommonButtonBase: NativeOnHovered/Unhovered/Pressed/Released(volta p/ Hovered se IsHovered senao Normal)/Enabled/Disabled. RefreshUIStyle agora chama ApplyVisualState(Normal). Compila OK. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>