Type is not assignable to type 'IStyleFunctionOrObject<IPanelStyleProps, IPanelStyles>

[lipalath-ms]

I have the following code:

                    <Panel
						isOpen={this.state.showPanel}
						onDismiss={this.onPanelClose}
						type={PanelType.medium}
						hasCloseButton={true}
						closeButtonAriaLabel="Close Submission Details"
						headerText={escape(strings.ListSubmissionsStatusPanelHeader)}
						isFooterAtBottom={true}
						onRenderFooterContent={this.renderFooter}
						styles={{root: {closeButton: {margin: '2px'} }}}
					>

On running this, I see:

error TS2322: Type '{ root: { closeButton: { margin: string; }; }; }' is not assignable to type 'IStyleFunctionOrObject<IPanelStyleProps, IPanelStyles>'

How do I fix this?