html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}
.cp #mainBlock {
  z-index: 1;
  height: 100%;
  width: 1000px;
  max-width: 90%;
  margin: auto;
  display: flex;
  align-items: center;
  justify-content: center;
}
.cp #mainBlock #container {
    text-align: center;
    font-size: 25px;
}