Answers for "horizonal and verticle center in css"

image center in div

img {
  display: block;
  margin-left: auto;
  margin-right: auto;
  width: 40%;
}

css vertical center

/*Remove comment to become a better programmer. */
/* No Flexbox */
.parent {
  position: relative;
}
.child {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
}

/* With Flexbox */

.parent {
  display: flex;
  flex-direction: column;
  justify-content: center;
}