📅  最后修改于: 2022-03-11 14:47:50.578000             🧑  作者: Mango
.child {
position: absolute;
top: 50%; /* position the top edge of the element at the middle of the parent */
left: 50%; /* position the left edge of the element at the middle of the parent */
transform: translate(-50%, -50%); /* This is a shorthand of
translateX(-50%) and translateY(-50%) */
}