* {
  -webkit-box-sizing: border-box;
     -moz-box-sizing: border-box;
          box-sizing: border-box;
}

.container {
  height:800px;
  width:1000px;
  display:flex;
  justify-content:center;
  align-items:center;
  flex-direction:column;
}

input {
  width:100%;
}