.outer {
  display: table;
  top: 0;
  left: 0;
  height: 100%;
  width: 100%;
}

.middle {
  display: table-cell;
  vertical-align: middle;
}

.inner {
  margin-left: auto;
  margin-right: auto;
  width: 50%;
  max-height: 80vh;
  overflow-y: auto;
}

/* Hide either side and expand upwards */
@media screen and (max-width: 500px) {
  .middle {
    vertical-align: initial;
  }

  .inner {
    /* 92% due to 2*4% padding */
    width: 92%;
    max-height: 90vh;
  }
}

.container {
  background: #fff;
  padding: 2% 4%;
  border-radius: 2%;
}

body {
  font-family: 'Source Sans Pro', sans-serif;
  margin: 0;
  height: 100vh;
  background-image: url('background.jpg');
  background-size: cover;
  background-repeat: no-repeat;
  overflow-y: hidden;
}

h1 {
  font-family: 'Raleway', sans-serif;
}

footer {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  text-align: center;
  margin-bottom: 2%;
}

footer, footer a {
  color: #fff;
}

a, a:visited {
  color: green;
}

.flex {
  display: flex;
}

.flex-item {
  flex: 1 1 auto;
  padding-left: 6px;
}