import React from 'react' ; const Bar = ( { animationDuration , progress } ) => ( < div style = { { background : '#29d' , height : 2 , left : 0 , marginLeft : `${ ( - 1 + progress ) * 100 }%` , position : 'relative' , top : 0 , transition : `margin-left ${ animationDuration }ms linear` , width : '100%' , zIndex : 1031 , } } />); export default Bar ;