* { box-sizing: border-box; }

body {
  font-family: serif;
  background-color: #333;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
}

a {
  font-weight: bold;
  color: inherit;
}

.page {
  display: flex;
  flex-direction: column;
  width: 60vh;
  height: 80vh;
  padding: 1rem;
  background-color: #FFF;
  transition: opacity 2s ease-in;
  opacity: 1;
}

.page[hidden] { opacity: 0; pointer-events: none; }

.heading {
  margin-top: 0;
}

.content {
  flex: 1;
  border-bottom: 1px solid #CCC;
}

.actions {
  margin: 0;
  padding: 0;
  list-style-type: none;
  font-style: italic;
  text-align: right;
}