center display block image code example

Example 1: css image center

.container {
    position: relative;
    float: right;
    width: 100%;
    height: 250px;
    overflow: hidden;
}

.container img {
    position: absolute;
    top: 50%;
    left: 50%;
    width: auto;
    min-width: 100%;
    height: 100%;
    /* height: auto; */
    /* min-height: 100%; */
    margin-right: -50%;
    transform: translate(-50%, -50%);
    object-fit: contain;
    -o-object-fit: contain;
}

Example 2: 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*/
}