// // puts a block right in the center of the window // import React from 'react' const CONTAINER_CSS = { position: 'absolute', display: 'flex', justifyContent: 'center', alignContent: 'center', alignItems: 'center', top: "0px", left: "0px", height: "100%", width: "100%" } const ITEM_CSS = { flex: "0 1 auto" } class Center extends React.Component { static get defaultProps() {return{ width: null }} constructor(props) { super(props) } render() { let style = this.props.width ? Object.assign({width: this.props.width + 'px'}, ITEM_CSS) : ITEM_CSS return (