* {
  box-sizing: border-box;
}

body, html {
  margin: 0;
  padding: 0;
  height: 100%;
  width: 100%;
}
body {
  overflow: hidden;
  font-size: 3.375vw;
  background: #000;
  font-family: "Fira Sans", "Open Sans", sans-serif;
  font-weight: 400;
  color: #4F0099;
}

.hide {
  visibility: hidden;
}

.fancy {
  box-shadow: 0 5px 5px rgba(0,0,0,.2);
  border-radius: 0 0 500px 500px / 0 0 4px 4px;
  position: relative;
  display: block;
}
.fancy:before, .fancy:after {
  box-shadow: 0 15px 5px rgba(0, 0, 0, .5);
  position: absolute;
  bottom: 15px;
  z-index: -1;
  width: 50%;
  display: block;
  max-width: 300px;
  content: "";
  height: 50px;
}
.fancy:after {
  transform: rotate(-3deg);
  left: 5px;
}
.fancy:before {
  transform: rotate(3deg);
  right: 5px;
}

.sepia {
  filter: sepia(70%);
}

section {
  width: 100vw;
  height: 56.25vw;
  margin: auto;
  position: absolute;
  bottom: 0;
  top: 0;
  left: 0;
  right: 0;
  display: none;
  background-image: radial-gradient(
    ellipse farthest-corner at center ,
    #eeeeee 70%,
    #c8c8c8
  );
  background-repeat: no-repeat;
  background-size: cover;
  padding: 1em;
  padding-bottom: 3em;

  justify-content: center;
  align-items: center;
  flex-direction: column;
}

section.full {
  padding: 0;
}

iframe {
  width: 80%;
  height: 90%;
  border: 0 none;
  background: hsl(40, 42%, 90%);
  box-shadow: 0 .2em .2em rgba(0,0,0,.3);
}

h1 {
  font-size: 2.2em;
}

h1, h2, h3, h4 {
  margin-top: 0;
  text-align: center;
  margin-bottom: 0;
  font-weight: 500;
  word-wrap: break-word;
  max-width: 80vw;
}

h2, h3, h4 {
  font-weight: 500;
}

@media (min-aspect-ratio: 16/9) {
  section {
    width: 177vh;
    height: 100vh;
  }
  body {
    font-size: 6vh;
  }
}

.note {
  font-size: .5em;
}

.center {
  text-align: center;
}

section.active {
  display: flex;
}

section img {
  object-fit: contain;
  max-width: 100%;
  max-height: 100%;
  flex: 1 1 100%;
  vertical-align: middle;
}

section > * + * {
  margin-top: .5em;
}

section .cols {
  width: 100%;
  flex: 1 1 auto;
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: space-around;
}
section .cols > * {
}
section .cols > * + *
}


section > .contain {
  pointer-events: none;
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100vw;
  height: 100vh;
  transform: translate(-50%, -50%);
  object-fit: contain;
  background: #000;
}

pre:first-child {
  margin-top: 0;
}
pre code {
  font-size: .5em;
  line-height: 1.2em;
}

h1:last-child {
  margin: 0;
}

ul {
  margin: 0;
}

.term {
  background: #222;
  color: #ddd;
  white-space: pre;
  width: 42ch;
  margin: 0 1ch;
  padding: 1ch;
}
.nowid {
  width: auto;
}
.fw {
  width: 100%;
}
.bigger {
  font-size: 1.5em;
}
.pr {
  position: relative;

}
.white {
  color: white;
}

blink {
  animation: 1s blink linear infinite;
}

@keyframes blink {
  50% {
    opacity: 1;
  }
  51% {
    opacity: 0;
  }
  to {
    opacity: 0;
  }
}

pre {
  max-width: 90%;
  max-height: 90%;
  margin-bottom: 0;
  overflow: auto;
}

.cani {
  width: 600px;
  height: 360px;
  transform: scale(1.5);
}

.stack > div {
  text-align: center;
  border: .1em solid black;
  margin-top: -.1em;
  display: flex;
  flex-direction: row;
  justify-content: center;
  min-width: 10em;
  line-height: 1.8
}
.stack > div > div {
  flex-grow: 1;
  width: 100%;
  text-align: center;
}
.stack > div > div + div {
  border: 0 none;
  border-left: .1em solid black;
}

.zoom-1-5 {
  width: 53%;
  height: 66%;
  transform: scale(1.5);
}

.zoom-2 {
  width: 40%;
  height: 50%;
  transform: scale(2);
}

.progress {
  position: absolute;
  bottom: 0px;
  height: 1vh;
  transition: 1s width ease-out;
  background: #000;
  width: 0%;
  border-radius: 1rem;
}
.talk-progress {
  bottom: 3.5vh;
  background: #4F0099;
  opacity: .9;
}
.time-progress {
  bottom: 1.5vh;
  background: #4F0099;
  opacity: .6;
}

.nope:before {
  z-index: 1;
  content: url(img/nope.svg);
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 70%;
}

.tall {
  height: 100vh;
}

section > .cover {
  pointer-events: none;
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100vw;
  height: 100vh;
  transform: translate(-50%, -50%);
  object-fit: cover;
}

section.css {
  padding-bottom: 3em;
}
section.css:after {
  content: 'CSS';
  color: #1CCCFF;
  font:normal 10vw true_crimesregular;
  transform: perspective(20vw) rotateY(-15deg) rotateX(2deg) skewY(-10deg) translate(-.2em, .1em);
  position: absolute;
  left: 1em;
  top: .5em;
}

.asotv {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 35%;
  transform: translate(-50%, -50%) rotate(10deg);
}