section {
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
  width: 100%;
  min-height: 100vh;
}

@media screen and (max-width: 768px) {
  section {
    /* padding: 25px 0px; */
  }
}



.panels section {
  min-height: 100%;
}

.panels section:nth-child(2) {
  min-height: calc(100% + 200px);
}

.panels section:nth-child(2n) {
}

.panels.horizontal {
  display: flex;
}

.panels.horizontal section {
  min-height: 0;
  min-width: 100%;
}

.panels.horizontal section:nth-child(2) {
  min-width: calc(100% + 200px);
}

section .explanation, section pre {
  background: #edf7f5;
}

section:nth-child(2n) .explanation, section:nth-child(2n) pre {
  background: #ffffff;
}

section.introduction {
  align-items: center;
  justify-content: center;
}

section.introduction .center {
  text-align: center;
}

section.introduction .center p {
  margin-left: auto;
  margin-right: auto;
  max-width: 900px;
}

section.introduction .center p a {
  word-break: break-all;
}

section.introduction .bottom {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding-bottom: 50px;
  text-align: center;
  font-size: 60%;
}

section.introduction .bottom:after {
  display: block;
  margin: 1em auto 0;
  height: 20px;
  width: 20px;
  border-right: 1px solid;
  border-bottom: 1px solid;
  content: '';
  -moz-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  -webkit-transform: rotate(45deg);
  transform: rotate(45deg);
}

section.options, section.options_explained {
  min-height: 100vh;
  height: auto;
}

a {
  color: inherit;
  text-decoration: underline;
}

.group {
  flex-grow: 1;
  display: flex;
  flex-wrap: wrap;
  margin: -25px;
}

.group > * {
  margin: 25px;
}

.panels, pre {
  flex-grow: 99999;
  flex-basis: 300px;
}

.panels {
  overflow: auto;
}