Inline style of Office Fabric UI library in spfx webpart

After upgraded the @microsoft/sp-office-ui-fabric-core library, all inline styles gone, to get it back, you just need to do:

import '@microsoft/sp-office-ui-fabric-core/lib/office-ui-fabric-core-sass/FabricCore.css';

Here is the test case:

public render(): React.ReactElement<IShortCutProps> {
	return (
		<div className={styles.shortCut}>
			<div className={styles.container}>
				<div className={styles.row}>
					{this.menus}
				</div>
			</div>
			<div className="ms-Grid" dir="ltr">
				<div className="ms-Grid-row">
					<div style={{ backgroundColor: 'red' }} className="ms-Grid-col ms-sm6 ms-md4 ms-lg2">A</div>
					<div style={{ backgroundColor: 'yellow' }} className="ms-Grid-col ms-sm6 ms-md8 ms-lg10">B</div>
				</div>
			</div>
		</div>
	);
}

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