</p> <style> <p>#t1 { font-size:12px;font-size-adjust: 0.58;}</p> <p>#t2 { font-size:12px;font-size-adjust: 1;}</p> <p>#t3 { font-size:12px;font-size-adjust: 0.2;}</p> </style> <div id="t1">A a pP X x</div> <div id="t2">A a pP X x</div> <div id="t3">A a pP X x</div> <p> [Ctrl+A 全部选择 提示：你可先修改部分代码，再按运行]

这是 W3Schools的解释

以下为引用内容:

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The ratio between the height of the font’s lowercase letter “x” and the height of the “font-size” is called a font’s aspect value. If the aspect value is high, the font will be legible when it is set to a smaller size. For example: Verdana has an aspect value of 0.58 (means that when font size is 100 px, its x-height is 58 px). Times New Roman has an aspect value of 0.46. This means that Verdana is more legible at smaller sizes than Times New Roman.

The font-size-adjust property specifies an aspect value for an element that will preserve the x-height of the first-choice font.

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