centering a vertical container of page in css code example

Example 1: css position element in the middle of a header

P.blocktext {
    margin-left: auto;
    margin-right: auto;
    width: 200px;/*usually works best with a fixed width*/
}

Example 2: centering horizontally

div.center{display:block;margin:auto;width:50%;}
p.center{text-align:center;}