@import url("https://fonts.googleapis.com/css?family=DM+Sans:400,700&display=swap");
:root {
  --duration: .8s;
  --ease: cubic-bezier(.7, 0, .3, 1);
}

*, *:before, *:after {
  box-sizing: border-box;
  position: relative;
}
*{margin:0;padding:0;list-style-type:none;}
html, body {
  height: 100%;
  width: 100%;
  margin: 0;
  padding: 0;
}

body {
  background: black;
  color: white;
  font-family: 'DM Sans', sans-serif;
}

img {
  max-width: 100%;
}

#app {
  height: 100%;
  width: 100%;
  display: grid;
  grid-template-columns: 1;
  grid-template-rows: 1fr 1fr;
}

.planet {
  grid-column: 1;
  grid-row: 1 / -1;
  overflow: hidden;
  height: 100%;
  width: 100%;
  display: grid;
  grid-template-columns: 10% 40% 40% 10%;
  grid-template-rows: 10% 1fr 1fr;
  grid-template-areas: "header header header header" "x title details y" "x planet photos photos";
}
.planet > .planet-title {
  display: block;
  grid-area: title;
}
.planet > .planet-figure {
  max-width: 900px;
  grid-column: 1 / -1;
  grid-row: planet;
  padding: 0;
  margin: 0 auto;
  position: relative;
}
.planet > .planet-figure img {
  margin-bottom: -50%;
  max-width: 100%;
}
.planet > .planet-figure::after {
  content: '';
  position: fixed;
  bottom: 0%;
  top: 0%;
  width: 100%;
  left: 0;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.7) 0%, transparent 30%);
  z-index: 2;
}
.planet > .planet-details {
  grid-area: details;
  display: flex;
  flex-direction: row;
  justify-content: space-between;
}

.detail {
  font-size: 5vmin;
  width: 3em;
  font-weight: 400;
  display: flex;
  margin-left: .4em;
  flex-shrink: 0;
  align-self: start;
}
.detail:after {
  content: attr(data-postfix);
}
.detail:before {
  display: block;
  position: absolute;
  top: 100%;
  margin-top: 1rem;
  font-size: .75rem;
  text-transform: uppercase;
  opacity: 0.6;
  letter-spacing: 1px;
}
.detail[data-detail="hours"]:before {
  content: "Hours";
}
.detail[data-detail="gravity"]:before {
  content: "gravity";
}
.detail[data-detail="tilt"]:before {
  content: "tilt";
}

h1, h2 {
  margin: 0;
}

/* ---------------------------------- */
.planet {
  visibility: hidden;
  transition: visibility 0.01s linear var(--duration);
}
.planet[data-active] {
  visibility: visible;
  opacity: 1;
  transition-delay: 0s;
}
.planet .planet-title .word {
  overflow: hidden;
}
.planet .planet-title .char {
  -webkit-transform: translateY(100%);
          transform: translateY(100%);
  transition: -webkit-transform var(--duration) var(--ease);
  transition: transform var(--duration) var(--ease);
  transition: transform var(--duration) var(--ease), -webkit-transform var(--duration) var(--ease);
  transition-delay: calc( var(--char-index) * .1s );
}
.planet[data-active] .planet-title .char {
  -webkit-transform: translateY(0%);
          transform: translateY(0%);
  transition-delay: calc( (var(--duration)/2) +  (var(--char-index) * .1s) );
}
.planet .planet-details {
  visibility: hidden;
}
.planet[data-active] .planet-details {
  visibility: visible;
}
.planet .planet-figure {
  opacity: 0;
  transition: opacity var(--duration) var(--ease);
}
.planet[data-active] .planet-figure {
  opacity: 1;
}

/* ---------------------------------- */
#app {
  overflow: hidden;
}

.planet-nav {
  grid-column: 1;
  grid-row: 2;
  pointer-events: none;
  z-index: 10;
  display: flex;
  position: absolute;
  left: 0;
  right: 0;
  margin: auto;
  bottom: 0;
  max-width: 1000px;
}
.planet-nav svg {
  display: block;
  width: auto;
  height: auto;
  min-width: 100%;
  max-width: none;
  min-height: 100vh;
  margin-bottom: -50%;
}
@media (max-width: 600px) {
  .planet-nav svg {
    margin-bottom: -55%;
  }
}
.planet-nav tspan {
  cursor: pointer;
  fill: #FFF;
  pointer-events: auto;
  opacity: 0;
  transition: opacity var(--duration) linear;
}
.planet-nav tspan[x] {
  opacity: 0.6;
}
.planet-nav tspan:hover, .planet-nav tspan:focus {
  opacity: 1;
}
.planet-nav svg {
  -webkit-transform-origin: center center;
          transform-origin: center center;
  --length: 7;
  --range: 160deg;
  -webkit-transform: rotate(calc(  (var(--active,0) / var(--length)) * (-1 * var(--range)) + (var(--range) / 2) ));
          transform: rotate(calc(  (var(--active,0) / var(--length)) * (-1 * var(--range)) + (var(--range) / 2) ));
  transition: -webkit-transform var(--duration) var(--ease);
  transition: transform var(--duration) var(--ease);
  transition: transform var(--duration) var(--ease), -webkit-transform var(--duration) var(--ease);
}
.planet-nav tspan {
  cursor: pointer;
}