(function(window, document) {
	var sizeUI = 750 // 定义设计图尺寸
	var remBase = 75 // 定义基准值
	var docEl = document.documentElement
	var bodyEl = document.querySelector('body')

	setRemUnit()

	window.addEventListener('resize', setRemUnit)
	window.addEventListener('pageshow', function(e) {
		if (e.persisted) setRemUnit()
	})

	function setRemUnit() {
		var docFontSize = docEl.clientWidth / sizeUI * remBase
		docEl.style.fontSize = docFontSize + 'px'
		bodyEl.style.fontSize = 16 / docFontSize + 'rem'
		handleRemAdapt()
	}

	function handleRemAdapt() {
		var currentFontSize = parseInt(docEl.style.fontSize)
		var temp = currentFontSize
		for (var i = 0; i < 100; i++) {
			var realFontSize = parseInt(window.getComputedStyle(docEl).fontSize)
			var differ = realFontSize - currentFontSize
			if (Math.abs(differ) >= 1) {
				if (differ > 0) {
					temp--
				} else {
					temp++
				}
				docEl.style.fontSize = temp + 'px'
			} else {
				break
			}
		}
	}
})(window, document)