It doesn't have to be exactly the same, but you are not elements that go beyond where it should be. If this happens, people will be sad. And then crazy. And then refuse to pay you if it works in more popular browsers.
I highly recommend not using Javascript for visual stuff; since this is Controller in the MVC pattern. In addition, the border radius is good, but it is not absolutely necessary, so there are no special reasons for its implementation in JS.
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