( ( window , document ) => { const docEl = document . documentElement ; const dpr = window . devicePixelRatio || 1 ; function setBodyFontSize ( ) { if ( document . body ) { document . body . style . fontSize = ( 12 * dpr ) + 'px' ; } else { document . addEventListener ( 'DOMContentLoaded' , setBodyFontSize ) ; } } setBodyFontSize ( ) ; function setRemUnit ( ) { const rem = docEl . clientWidth / 10 ; docEl . style . fontSize = rem + 'px' ; } setRemUnit ( ) ; window . addEventListener ( 'resize' , setRemUnit ) ; window . addEventListener ( 'pageshow' , ( e ) => { if ( e . persisted ) { setRemUnit ( ) ; } } ) ; if ( dpr >= 2 ) { const fakeBody = document . createElement ( 'body' ) ; const testElement = document . createElement ( 'div' ) ; testElement . style . border = '.5px solid transparent' ; fakeBody . appendChild ( testElement ) ; docEl . appendChild ( fakeBody ) ; if ( testElement . offsetHeight === 1 ) { docEl . classList . add ( 'hairlines' ) ; } docEl . removeChild ( fakeBody ) ; } } ) ( window , document ) ;