body
{
  margin: 0;
  padding: 0;
  font-family: Arial, sans-serif;
  background-color: #f0f0f0;
}

.container
{
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%,-50%);
  text-align: center;
  background-color: #fff;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
  max-width: 400px;
  width: 90%;
}

h1
{
  font-size: 22px;
  margin-bottom: 10px;
}

@media screen and (max-width: 768px)
{
  .container{ max-width: 90%; }
}