#border-top-left-radius

Defines the radius of the top left corner.

默认属性 border-top-left-radius: 0;

Removes any border radius.

border-top-left-radius: 20px;

You can use pixel values.

border-top-left-radius: 50%;

You can use percentage values. In this example, the radius starts halfway on the top border, and ends halfway on the left border.

border-top-left-radius: 20px 50%;

If you set two values, the first one is for the top border, the second one for the left border.