css get screen width and height center code example
Example 1: css center element on screen
.centered {
position: fixed;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
}
Example 2: center div in middle of page
.centered {
position: fixed;
top: 50%;
left: 50%;
/* bring your own prefixes */
transform: translate(-50%, -50%);
}