Как сосредоточиться
.center {
position: fixed;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
}
Puzzled Penguin
.center {
position: fixed;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
}
margin-left: auto;
margin-right: auto;
https://stackoverflow.com/questions/1725759/css-how-to-center-box-div-element-directly-in-center