*, *:before, *:after {
  box-sizing: border-box;
}

* {
  margin: 0;
}

@font-face {
  font-family: "Inter";
  src: url("./fonts/Inter-Variable.ttf") format("truetype");
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: "Inter";
  src: url("./fonts/Inter-Variable-Italic.ttf") format("truetype");
  font-weight: 100 900;
  font-style: italic;
  font-display: swap;
}

@property --universePerspective {
  syntax: "<length>";
  initial-value: 600px;
  inherits: true;
}
@property --waterX {
  syntax: "<length>";
  initial-value: 0px;
  inherits: true;
}
@property --waterY {
  syntax: "<length>";
  initial-value: 0px;
  inherits: true;
}
@property --worldTiltOffset {
  syntax: "<angle>";
  initial-value: 0deg;
  inherits: true;
}
@property --universeRotateZ {
  syntax: "<angle>";
  initial-value: 0deg;
  inherits: true;
}
@property --skyWidthOverflow {
  syntax: "<length>";
  initial-value: 175px;
  inherits: true;
}
@property --universeTranslateY { syntax: "<length>"; initial-value: 0px; inherits: true; }
@property --universePerspectiveOriginYOffset { syntax: "<length>"; initial-value: 0px; inherits: true; }
@property --fovY { syntax: "<angle>"; initial-value: 57deg; inherits: true; } /* optional */

@property --skyTranslateX { syntax: "<length>"; initial-value: 0px; inherits: true; }
@property --skyTranslateY { syntax: "<length>"; initial-value: -200px; inherits: true; }
@property --skySlideYOffset { syntax: "<length>"; initial-value: 100px; inherits: true; }
@property --skyPositionX { syntax: "<length>"; initial-value: 0px; inherits: true; }

@property --airshipRotationShift { syntax: "<length>"; initial-value: 0px; inherits: true; }
@property --airshipTranslateZ { syntax: "<length>"; initial-value: 350px; inherits: true; }
@property --airshipAltitude { syntax: "<length>"; initial-value: 60px; inherits: true; }
@property --airshipAltitudeRaw { syntax: "<number>"; initial-value: 0.6; inherits: true; }
@property --shadowScale { syntax: "<number>"; initial-value: 1; inherits: true; }

@property --worldOriginX { syntax: "<percentage>"; initial-value: 50%; inherits: true; }
@property --worldOriginY { syntax: "<length>"; initial-value: calc(var(--refH) * 1px - 20px); inherits: true; }
@property --worldTilt { syntax: "<angle>"; initial-value: 67deg; inherits: true; }

@property --skyTileWidth { syntax: "<length>"; initial-value: 32px; inherits: true; }
@property --waterTileSize { syntax: "<length>"; initial-value: 512px; inherits: true; }

:root {
  --bgX: 0;
  --bgY: 0;

  --refW: 1512;
  --refH: 797;

  --vw: 100vw;
  --vh: 100vh;

  --pixelZoom: 1;
  --pixelScaleComp: 1;

  --sx: calc(var(--vw) / var(--refW));
  --sy: calc(var(--vh) / var(--refH));

  --s-contain: min(var(--sx), var(--sy));
  --s-cover: max(var(--sx), var(--sy));

  --s: var(--s-cover);
  --contentW: calc(var(--refW) * var(--s));
  --contentH: calc(var(--refH) * var(--s));
  --offsetX: calc((var(--vw) - var(--contentW)) / 2);
  --offsetY: calc((var(--vh) - var(--contentH)) / 2);
  --zRef: 1vmin;
  --worldTiltBaseline: 67deg;
  --worldTiltAtMaxAltitude: 67deg;
  --worldTiltAtMinAltitude: 72deg;
  --worldTiltOffset: 0deg;
  --worldTiltFromAltitude: calc(
    var(--worldTiltAtMinAltitude) +
    (var(--worldTiltAtMaxAltitude) - var(--worldTiltAtMinAltitude)) * var(--airshipAltitudeRaw)
  );
  --worldTilt: calc(var(--worldTiltFromAltitude) + var(--worldTiltOffset));

  --pitch:  var(--worldTiltOffset);
  --horizon: calc(
    (var(--refH) * 1px) / 2
    - var(--universePerspective) * tan(var(--pitch))
  );

  --shadowScreenOffset: 20px;
  --groundAnchorY: calc(var(--refH) * 1px - var(--shadowScreenOffset));

  --universeHeight: 100vh;

  --universeRotationShiftX: calc(
    -0.5 * var(--universeHeight) * sin(var(--universeRotateZ))
  );
  --universeRotationShiftY: calc(
    0.5 * var(--universeHeight) * (1 - cos(var(--universeRotateZ)))
  );

  --fovY: 57deg;
  --universePerspective: calc((var(--refH) * 1px / 2) / tan(var(--fovY) / 2));
  --universePerspectiveOriginX: 50%;
  --universePerspectiveOriginY: 50%;
  --universePerspectiveOriginYOffset: 0px;
  --universePerspectiveOrigin: var(--universePerspectiveOriginX) calc(var(--universePerspectiveOriginY) + var(--universePerspectiveOriginYOffset));
  --skyPositionX: 0px;
  --skyTranslateY: -300px;
  --skySlideYOffset: 200px;
  --skyHeight: calc(var(--refH) * 1px - var(--horizon) + var(--skySlideYOffset));
  --skyWidthOverflow: 175px;
  --universeTranslateY: 0px;
  --universeRotateZ: 0deg;
  --skyTranslateX: calc(var(--skyWidthOverflow) / 2 * -1);
  --universeWidth: 100%;
  --airshipTranslateX: -50%;
  --airshipTranslateY: -50%;
  --worldOriginX: 50%;
  --worldOriginY: var(--groundAnchorY);
  --worldRotateZ: 90deg;
  --airshipTranslateZ: 350px;
  --airshipAltitudeYGain: 0.8;

  --minWorldOriginZ: 180px;
  --maxWorldOriginZ: 480px;

  --minWorldTranslateZ: 400px;
  --maxWorldTranslateZ: 800px;
  --minAltitude: 0px;
  --maxAltitude: 100px;
  --minAltitudeRaw: 0;
  --maxAltitudeRaw: 1;
  --airshipAltitude: 60px;
  --airshipAltitudeRaw: 0.6;
  --waterTileSize: 512px;
  --waterX: 0px;
  --waterY: 0px;
  --skyTileWidth: 32px;

  --glareColorSunsetA: rgba(255, 180, 80, 0.55) 0%;
  --glareColorSunsetB: rgba(255, 180, 80, 0.32) 14%;
  --glareColorSunsetC: rgba(255, 180, 80, 0.12) 34%;
  --glareColorSunsetD: rgba(255, 180, 80, 0) 65%;

  --glareColorDaylightA: rgba(160, 220, 255, 0.55) 0%;
  --glareColorDaylightB: rgba(160, 220, 255, 0.32) 15%;
  --glareColorDaylightC: rgba(210, 215, 255, 0.18) 32%;
  --glareColorDaylightD: rgba(255, 200, 150, 0.08) 50%;
  --glareColorDaylightE: rgba(255, 180, 80, 0) 72%;

  --cloudImageWidth: 1536px;
  --cloudImageHeight: 850px;

  --shadowScale: 1;

  --worldOriginXCorrected: calc(
    var(--worldOriginX)
  );
  --worldOriginYCorrected: calc(
    var(--worldOriginY) + (var(--universePerspectiveOriginYOffset) / 2) +
      var(--universeTranslateY)
  );
  --worldTranslateZPerAltitude: calc(
    (var(--maxWorldTranslateZ) - var(--minWorldTranslateZ)) /
      (var(--maxAltitudeRaw) - var(--minAltitudeRaw))
  );
  --worldOriginZPerAltitude: calc(
    (var(--maxWorldOriginZ) - var(--minWorldOriginZ)) /
      (var(--maxAltitudeRaw) - var(--minAltitudeRaw))
  );
  --clampedWorldTranslateZ: clamp(
    var(--minWorldTranslateZ),
    calc(
      var(--maxWorldTranslateZ) -
        (var(--airshipAltitudeRaw) * var(--worldTranslateZPerAltitude))
    ),
    var(--maxWorldTranslateZ)
  );
  --clampedWorldOriginZ: clamp(
    var(--minWorldOriginZ),
    calc(
      var(--maxWorldOriginZ) -
        (var(--airshipAltitudeRaw) * var(--worldOriginZPerAltitude))
    ),
    var(--maxWorldOriginZ)
  );


  --widthGrossRotateScale: abs(calc(cos(var(--worldTiltBaseline)) + sin(var(--worldTiltBaseline))));

  --airshipRotationShift: var(--universeRotationShiftX);

  --pixelZoom: 1; 
  --pixelScaleComp: 1;

  &:has(.sky.rotate-left-enter) {
    --universeRotateZ: -7deg;

    transition:
      --universeRotateZ 0.3s ease,
  }

  &:has(.sky.rotate-right-enter) {
    --universeRotateZ: 7deg;
    --skyTranslateX: calc(var(--skyWidthOverflow) / 2 * -1);

    transition:
      --universeRotateZ 0.3s ease,
  }

  &:has(.sky.rotate-left-enter.slide-down-enter) {
    --skyTranslateX: calc(var(--skyWidthOverflow) / 2 * -1);
  }

  &:has(.sky.rotate-right-exit) 
  &:has(.sky.rotate-left-exit)  {
    transition:
      --universeRotateZ 0.3s ease,
  }
}

.universe .world {
  --worldTiltOffset: 0deg;
}

.universe:has(.sky.slide-up-enter) .world {
  --worldTiltOffset: -5deg;
}
.universe:has(.sky.slide-down-enter) .world {
  --worldTiltOffset: 5deg;
}
.universe:has(.sky.slide-up-exit) .world,
.universe:has(.sky.slide-down-exit) .world {
  --worldTiltOffset: 0deg;
}

@keyframes waterDrift {
  from {
    --waterX: 0px;
    --waterY: 0px;
  }
  to {
    --waterX: calc(-1 * var(--waterTileSize));
    --waterY: 0px;
  }
}

@keyframes minimapBlink {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.25;
  }
}

html,
body {
  background-color: transparent;
  margin: 0;
  padding: 0;
  overflow: clip;
  position: relative;
  width: var(--vw);
  height: var(--vh);
  font-family: "Inter", sans-serif;
  mask: linear-gradient(#000 0 0);
  transform-origin: top left;
}


@supports (zoom: 1) {
  body {
    zoom: var(--pixelZoom);
    transform: scale(var(--pixelScaleComp));
  }
}

@supports not (zoom: 1) {
  body {
    width: calc(var(--vw) / var(--pixelScaleComp));
    height: calc(var(--vh) / var(--pixelScaleComp));
    transform: scale(var(--pixelScaleComp));
  }
}

.universe {
  background-color: transparent;

  width: var(--vw);
  height: calc(var(--refH) * 1px);
  position: absolute;

  clip-path: inset(-250px);

  perspective: var(--universePerspective);
  perspective-origin: var(--universePerspectiveOrigin);

  transform: translate3d(
      var(--universeRotationShiftX),
      calc(var(--universeTranslateY) + var(--universeRotationShiftY)),
      0
    )
    rotateZ(var(--universeRotateZ));
  will-change: transform;
  transition:
    transform 0.3s ease,
    width 0.3s ease;


  &:has(.sky.slide-down-enter) {
    --universeTranslateY: 100px;
  }
  &:has(.sky.slide-up-enter) {
    --universeTranslateY: -100px;
  }

  &:has(.sky.rotate-left-enter) .world,
  &:has(.sky.rotate-right-enter) .world {
    animation-play-state: paused;
  }
}

.paused-text {
  position: absolute;
  left: 50%;
  top: 50%;
  z-index: 6;
  font-family: "Courier New", Courier, monospace;
  font-size: 48px;
  font-weight: 700;
  letter-spacing: 0.5rem;
  line-height: 1;
  color: #fff;
  text-transform: uppercase;
  text-shadow:
    2px 2px 0 #000,
    -2px 2px 0 #000,
    2px -2px 0 #000,
    -2px -2px 0 #000;
  transform: translate(-50%, -50%);
  opacity: 0;
}

body:has(#pause.paused) .paused-text {
  opacity: 1;
}

.sky {
  position: absolute;
  top: 0;
  left: 0;
  width: calc(var(--vw) + var(--skyWidthOverflow));
  height: var(--skyHeight);
  background: url("clouds.png"), url("sky2.png");
  background-repeat: repeat, repeat;
  background-size:
    calc(var(--cloudImageWidth) / 2) calc(var(--cloudImageHeight) / 2),
    calc(var(--skyTileWidth) * 2) var(--skyHeight);
  background-position:
    calc(var(--skyPositionX)) 140px,
    calc(var(--skyPositionX) * 0.75) 0;
  z-index: 1;
  transform: translate3d(var(--skyTranslateX), var(--skyTranslateY), 0);
  will-change: transform, background-position;
  backface-visibility: hidden;
  transition:
    transform 0.3s ease,
    height 0.3s ease,
    width 0.3s ease;
}

.haze {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(
      to top,
      color-mix(in oklab, #000 0%, transparent 100%) 0%,
      color-mix(in oklab, #000 0%, transparent 100%) var(--horizon, 62%),
      color-mix(in oklab, #3f729d 45%, transparent 55%) 100%
    );
  mix-blend-mode: soft-light;
  opacity: 0.8;
  z-index: 2;
}

.glare {
  position: absolute;
  left: 0;
  top: 0;
  width: calc(var(--vw) + var(--skyWidthOverflow));
  height: 200px;
  pointer-events: none;
  z-index: 3;
  transform: translate3d(0, var(--skyHeight), 0);
  will-change: transform;

  transition:
    transform 0.3s ease,
    height 0.3s ease,
    width 0.3s ease;

  background: linear-gradient(
    to bottom,
    var(--glareColorDaylightA),
    var(--glareColorDaylightB),
    var(--glareColorDaylightC),
    var(--glareColorDaylightD),
    var(--glareColorDaylightE)
  );
  mix-blend-mode: screen;
}

.world {
  --worldHeight: 4900px;
  --worldTranslateY: calc(-1 * var(--worldHeight) / 2);
  --worldWidthOverscan: 1600px;
  
  animation: waterDrift 15s linear infinite;
  width: calc(var(--vw) + var(--worldWidthOverscan));
  height: var(--worldHeight);
  transform: translateX(calc(-1 * (var(--worldWidthOverscan)) / 2)) rotateX(var(--worldTilt)) rotateZ(var(--worldRotateZ)) translateY(var(--worldTranslateY)) translateZ(var(--clampedWorldTranslateZ));
  transform-origin: var( --worldOriginXCorrected) var(--worldOriginYCorrected) var(--clampedWorldOriginZ);
  background-color: #0a2740;
  background-image: url("./world.png"), url("./water.png");
  background-repeat: repeat, repeat;
  background-size:
    4096px 4096px,
    var(--waterTileSize) var(--waterTileSize);
  background-position:
    calc(var(--worldOriginXCorrected) + var(--bgX)) calc(var(--worldOriginYCorrected) + var(--bgY)),
    calc(var(--worldOriginXCorrected) + var(--bgX) + var(--waterX, 0px))
      calc(var(--worldOriginYCorrected) + var(--bgY) + var(--waterY, 0px));
  image-rendering: pixelated;
  position: relative;
  will-change: transform, background-position, transform-origin;
  backface-visibility: hidden;
  transition: --worldTiltOffset 0.3s ease;
}

.airship {
  image-rendering: pixelated;
  background-image: url("./airship.png");
  background-repeat: no-repeat;
  width: 72px;
  height: 72px;
  position: absolute;
  bottom: calc(
    var(--shadowScreenOffset) +
    var(--airshipTranslateZ) * sin(var(--worldTilt)) +
    (var(--airshipAltitude) * var(--airshipAltitudeYGain))
  );
  left: 50%;
  transform-origin: 50% 100%;
  transform: translateX(-50%) translateZ(var(--airshipTranslateZ));
  z-index: 999;
}

.shadow {
  --shadowWidth: 100px;
  --shadowHeight: 200px;

  width: var(--shadowWidth);
  height: var(--shadowHeight);
  background: rgba(0, 0, 0, 0.7);
  border-radius: 50%;
  position: absolute;
  left: 50%;
  bottom: 20px;
  transform: rotateZ(calc(-1 * var(--universeRotateZ))) rotateX(125deg)
    translateX(
      calc(
        var(--clampedWorldTranslateZ) * sin(var(--universeRotateZ)) -
          (var(--shadowWidth) / 2)
      )
    )
    translateZ(1px) scale(var(--shadowScale));
  transition: transform 0.3s ease;
}

/* This is just for debugging purposes */
.origin-marker {
  --markerSize: 5px;

  display: none;
  position: absolute;
  width: var(--markerSize);
  height: var(--markerSize);
  background: red;
  border-radius: 50%;
  /* Place marker at corrected world pivot (after countering universe shift) */
  left: calc(var(--worldOriginXCorrected) - var(--markerSize) / 2);
  top: calc(var(--worldOriginYCorrected) - var(--markerSize) / 2);
  transform: translateZ(1px);
}

.debug-mode .origin-marker {
  display: block;
}

main {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: flex-end;
  height: var(--vh);
  width: var(--vw);
  position: absolute;
}

section {
  background: black;
  display: flex;
  flex-direction: column;
  padding: 30px;
  text-align: center;
  gap: 24px;
  width: var(--vw);
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: space-between;
}

h3,
p,
a {
  color: white;
  margin: 0;
  font-family: "Inter", sans-serif;
}

a {
  text-transform: uppercase;
}

h3 {
  text-transform: uppercase;
}

aside {
  position: absolute;
  top: 20px;
  right: 20px;
  display: flex;
  gap: 8px;
  z-index: 5;
}

@media (hover: none) {
  #controls-toggle {
    display: none;
  }
}

.primary-button {
  appearance: none;
  display: grid;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 999px;
  background: #111;
  color: #fff;
  font-size: 18px; 
  line-height: 1;
  margin: 0;
  opacity: 0.5;
  cursor: pointer;
  place-items: center;
  transition: opacity 0.3s ease;
}
.primary-button:active {
  transform: translateY(1px);
}

.primary-button.active {
  opacity: 1;
}

.controls-modal {
  position: absolute;
  left: 50%;
  top: 50%;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.3s ease;
  transform: translate(-50%, -50%);
  z-index: 5;
  display: flex;
  align-items: flex-end;
  color: #fff;
  max-width: 300px;
}

.controls-modal[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

#pause svg .play { display: none; }
#pause svg .pause { display: inline; }

#pause.paused svg .play { display: inline; }
#pause.paused svg .pause { display: none; }


.minimap {
  --minimapSize: 300px;
  position: absolute;
  width: var(--minimapSize);
  height: var(--minimapSize);
  pointer-events: none;
  left: 50%;
  top: 50%;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease;
  z-index: 4;
  background-color: rgba(30, 52, 68, 0.55);
  background-image: url("./world.png");
  background-size: 100% 100%;
  image-rendering: pixelated;
  filter: saturate(0) contrast(1.18) brightness(0.8) blur(0.35px);
  transform: translate(-50%, -50%);
}

.minimap[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.minimap-airship {
  position: absolute;
  top: calc(var(--minimapAirshipY, 0.5) * 100%);
  left: calc(var(--minimapAirshipX, 0.5) * 100%);
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #fff;
  transform: translate(-50%, -50%);
  animation: minimapBlink 0.8s steps(1, end) infinite;
}

@media all and (min-width: 600px) {
  .primary-button {
    bottom: 20px;
    top: unset;
  }

  .minimap {
    --minimapSize: 240px;
    left: auto;
    top: auto;
    right: 40px;
    bottom: 40px;
    transform: none;
  }

  section {
    display: inline-flex;
    margin-bottom: 40px;
    margin-left: 40px;
    margin-right: 40px;
    width: auto;
  }

  .controls-modal {
    left: auto;
    right: 0;
    bottom: 0;
    top: auto;
    transform: none;
  }
}

@media all and (min-height: 900px) {
  .universe {
    clip-path: inset(-800px);
  }

  .world {
    --worldHeight: 6400px;
  }
}

@media all and (min-width: 1600px) {
  .world {
    --worldWidthOverscan: calc(var(--refW) * 2px);
  }
}

@media (resolution: 1.5dppx), (-webkit-min-device-pixel-ratio: 1.5) {
  :root{
    --pixelZoom: 0.666667;
    --pixelScaleComp: 1.5;
  }
}

@media (resolution: 2dppx), (-webkit-min-device-pixel-ratio: 2) {
  :root{
    --pixelZoom: 0.5;
    --pixelScaleComp: 2;
  }
}

@media (resolution: 3dppx), (-webkit-min-device-pixel-ratio: 3) {
  :root{
    --pixelZoom: 0.333333;
    --pixelScaleComp: 3;
  }
}

@media (resolution: 4dppx), (-webkit-min-device-pixel-ratio: 4) {
  :root{
    --pixelZoom: 0.25;
    --pixelScaleComp: 4;
  }
}

@supports (width: 100dvw) {
  :root {
    --vw: 100dvw; 
  }
}

@supports (height: 100dvh) {
  :root { --vh: 100dvh; }
}


@supports (font: -apple-system-body) {
  :root{
    --pixelZoom: 1;
    --pixelScaleComp: 1;
  }
}