border-radius

基本解释

When the ball is painted, the border radius means that the edges are anti-aliased.
当球被画时，边界半径意味着边缘是消除锯齿的。
To stick with the border-radius example, consider what happens when you want to target just one corner of an object.
让我们继续停留在这个圆角效果的例子上，设想一下假如你只想应用到一个对象的一个角上会产生什么情况。
While it’s much easier today to make curves on web pages using the canvas, CSS properties like border-radius, or just plain background images, it’s still not always trivial.
虽然用画布、CSS属性如border-radius，或者就用纯背景图，今天画曲线已经容易多了，但是仍然不常见。