:root {
  --bg-a: #d8dade;
  --bg-b: #d2d4d8;
  --bg-c: #c8cbcf;
  --text: #606873;
  --link: #2f3a49;
  --hedgehog-filter: none;
  --hedgehog-shadow: 0 14px 38px rgba(0, 0, 0, 0.12);
}

body.theme-dark {
  --bg-a: #141b23;
  --bg-b: #0f151d;
  --bg-c: #0b1118;
  --text: #c7d2df;
  --link: #edf5ff;
  --hedgehog-filter: brightness(0) invert(1);
  --hedgehog-shadow: 0 20px 50px rgba(0, 0, 0, 0.45);
}

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

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  min-height: 100svh;
  overflow: hidden;
  background:
    radial-gradient(circle at 52% 42%, var(--bg-a) 0%, var(--bg-b) 68%, var(--bg-c) 100%);
  color: var(--text);
  font-family: "Avenir Next", "Gill Sans", "Trebuchet MS", sans-serif;
  transition: background 220ms ease, color 220ms ease;
}

.stage {
  min-height: 100svh;
  display: grid;
  place-items: center;
  padding: 2rem;
}

.hedgehog {
  appearance: none;
  border: 0;
  background: transparent;
  cursor: pointer;
  position: relative;
  width: min(56vmin, 520px);
  aspect-ratio: 100 / 125;
  padding: 0;
  user-select: none;
  filter: drop-shadow(var(--hedgehog-shadow));
  transition: filter 220ms ease;
}

.hedgehog:focus-visible {
  outline: 2px solid color-mix(in srgb, var(--link) 70%, white 30%);
  outline-offset: 0.4rem;
}

.hedgehog-base {
  display: block;
  width: 100%;
  height: 100%;
  filter: var(--hedgehog-filter);
  transition: filter 220ms ease;
  pointer-events: none;
}

.eye {
  position: absolute;
  transform-origin: 50% 50%;
  transform: rotate(var(--rotation, 0deg));
  will-change: transform;
  filter: var(--hedgehog-filter);
  transition: filter 220ms ease;
  pointer-events: none;
}

.eye-left {
  left: 12.48%;
  top: 52.704%;
  width: 6.62%;
}

.eye-right {
  left: 23.6%;
  top: 56.384%;
  width: 5.51%;
}

.caption {
  position: fixed;
  left: clamp(1rem, 2.5vw, 2.25rem);
  bottom: clamp(1rem, 2.7vw, 2.25rem);
  margin: 0;
  font-size: clamp(0.95rem, 1.35vw, 1.2rem);
  letter-spacing: 0.02em;
}

.caption a {
  color: var(--link);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.14em;
}

.caption a:hover {
  opacity: 0.78;
}

@media (max-width: 640px) {
  .hedgehog {
    width: min(72vmin, 430px);
  }
}