flex-center

<div class="container">
  <div>Hello</div>
</div>

////////* 1st method *////////
.container{ //Body can be used
  display:flex;
  height:100vh;
  align-items: center;
  justify-content: center;
}
body {
  margin: 0 auto; // Removes the scroll bar
}


////////* 2nd method *////////
.container {
  display: flex;
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  top: 0;
  overflow: hidden;
    div {
      align-self: center;
      margin: auto;
    }
}