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<p style="font-size:0.1rem">rem的使用：根据屏幕大小自动改变字体大小</p>
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<script>
(function() {
var newRem = function() {
var html = document.documentElement;
html.style.fontSize = html.getBoundingClientRect().width / 10 + ‘px‘;
};
window.addEventListener(‘resize‘, newRem, false);
newRem();
})();
</script>
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原文：http://www.cnblogs.com/liyuhuan/p/7474351.html