:root {
  --night: #0e1a24;
  --dusk: #172836;
  --deep: #0a131b;
  --snow: #eef3f6;
  --frost: #9fb6c6;
  --ice: #8fd0f0;
  --line: rgba(238, 243, 246, 0.14);
  --display: 'Big Shoulders Display', 'Arial Narrow', 'Helvetica Neue', Arial, sans-serif;
  --text: 'Newsreader', Georgia, 'Times New Roman', serif;
  --mono: ui-monospace, 'SF Mono', Menlo, Consolas, 'Liberation Mono', monospace;
  --gutter: max(20px, env(safe-area-inset-left, 0px));
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  margin: 0;
  background: var(--night);
  color: var(--snow);
  font: 400 1.125rem/1.6 var(--text);
  font-optical-sizing: auto;
}

a {
  color: var(--ice);
  text-underline-offset: 0.18em;
}

:focus-visible {
  outline: 2px solid var(--ice);
  outline-offset: 3px;
}

.skip {
  position: absolute;
  left: var(--gutter);
  top: -100px;
  z-index: 10;
  background: var(--snow);
  color: var(--night);
  padding: 8px 14px;
  border-radius: 6px;
}

.skip:focus {
  top: 12px;
}

/* Hero: the wordmark is the stage for the snow. */

.hero {
  position: relative;
  min-height: min(100vh, 920px);
  display: flex;
  flex-direction: column;
  padding: 28px var(--gutter) 72px;
  background:
    radial-gradient(120% 70% at 50% 0%, #1d3346 0%, rgba(29, 51, 70, 0) 70%),
    var(--night);
  overflow: hidden;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 22px;
  font: 700 1.05rem/1 var(--display);
  letter-spacing: 0.03em;
}

.nav a {
  color: var(--frost);
  text-decoration: none;
  padding: 6px 0;
}

.nav a:hover {
  color: var(--snow);
}

.wordmark {
  margin: auto 0 0;
  padding-top: 18vh;
  font: 900 clamp(2.8rem, 15.5vw, 16rem) / 0.82 var(--display);
  letter-spacing: 0.005em;
  color: var(--snow);
  white-space: nowrap;
}

.wordmark .letter {
  display: inline-block;
  /* A sliver of space so each letter wears its own cap of snow. */
  margin-right: 0.035em;
  /* Box tops sit on the cap height, so snow lands on the letters, not above them. */
  text-box: trim-both cap alphabetic;
}

.hero-copy {
  min-width: 0;
  max-width: 40rem;
  margin-top: 36px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 18px;
}

.lead {
  margin: 0;
  font-size: clamp(1.25rem, 2.4vw, 1.6rem);
  line-height: 1.45;
}

.hint {
  margin: 0;
  color: var(--frost);
  font-style: italic;
  font-size: 1rem;
}

.install {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  max-width: 100%;
  background: var(--deep);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px 8px 8px 16px;
  justify-self: start;
}

.install code {
  min-width: 0;
  font: 0.95rem/1.4 var(--mono);
  overflow-x: auto;
  white-space: nowrap;
}

.copy,
.choices button,
.action {
  font: 700 1.05rem/1 var(--display);
  letter-spacing: 0.03em;
  color: var(--snow);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 9px 16px;
  cursor: pointer;
}

.copy:hover,
.choices button:hover,
.action:hover {
  border-color: var(--frost);
}

.choices button[aria-pressed='true'] {
  background: var(--hue, var(--ice));
  border-color: var(--hue, var(--ice));
  color: var(--night);
}

.reduced {
  margin: 0;
  padding: 14px var(--gutter);
  background: var(--dusk);
  color: var(--snow);
  border-block: 1px solid var(--line);
}

/* Plates: one per effect. */

main {
  padding: 0 var(--gutter);
}

.plate {
  max-width: 1120px;
  margin: 0 auto;
  padding-block: 96px 24px;
}

.plate-head {
  max-width: 44rem;
  margin-bottom: 28px;
}

.plate-head h2 {
  margin: 0 0 10px;
  font: 900 clamp(2.8rem, 6vw, 4.5rem) / 0.95 var(--display);
  letter-spacing: 0.01em;
  text-wrap: balance;
}

.plate-head h2::before {
  content: '';
  display: inline-block;
  width: 0.32em;
  height: 0.32em;
  margin-right: 0.28em;
  vertical-align: 0.12em;
  border-radius: 2px;
  background: var(--hue);
}

.plate-head p {
  margin: 0;
  color: var(--frost);
  font-size: 1.2rem;
}

.stage {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 8;
  border-radius: 14px;
  overflow: hidden;
  background: var(--dusk);
  box-shadow: inset 0 0 0 1px var(--line);
}

.plate-body {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: 32px;
  margin-top: 28px;
}

.notes {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  align-content: start;
}

.notes p {
  margin: 0;
}

.choices {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
}

.toggle input {
  width: 18px;
  height: 18px;
  accent-color: var(--hue);
}

.meta {
  color: var(--frost);
  font-size: 1rem;
}

.meta code {
  font: 0.9rem var(--mono);
  color: var(--snow);
}

kbd {
  display: inline-block;
  min-width: 1.6em;
  padding: 1px 6px;
  border: 1px solid var(--line);
  border-bottom-width: 2px;
  border-radius: 5px;
  font: 0.85rem/1.4 var(--mono);
  text-align: center;
  color: var(--snow);
}

.code {
  margin: 0;
  min-width: 0;
  background: var(--deep);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 18px 20px;
  font: 0.9rem/1.65 var(--mono);
  color: #cfdfe9;
  overflow-x: auto;
  white-space: pre;
}

.code .s {
  color: #a8dcb4;
}

.code .c {
  color: var(--frost);
  font-style: italic;
}

.code .k {
  color: var(--ice);
}

/* Ripples: a painted lake (see app.js). */

.stage-ripples {
  background-color: #1b3346;
  background-size: cover;
  background-position: center;
  cursor: crosshair;
}

/* Weather: a night town for the snow to settle on. */

.stage-weather {
  background: linear-gradient(#0b1621 0%, #16283a 55%, #1f3850 100%);
}

.town {
  position: absolute;
  inset: 0;
}

.roof {
  position: absolute;
  left: var(--x);
  width: var(--w);
  height: var(--h);
  bottom: 0;
  background:
    repeating-linear-gradient(90deg, transparent 0 18px, rgba(255, 214, 120, 0.85) 18px 26px, transparent 26px 44px) 10px 22px / calc(100% - 20px) 10px no-repeat,
    repeating-linear-gradient(90deg, transparent 0 30px, rgba(255, 214, 120, 0.6) 30px 38px, transparent 38px 52px) 14px 56px / calc(100% - 28px) 10px no-repeat,
    #08111a;
}

/* Fluid. */

.stage-fluid {
  background: #070d13;
  display: grid;
  place-items: center;
}

.stage-label {
  position: relative;
  margin: 0;
  font: 900 clamp(2rem, 6vw, 4.5rem) / 1 var(--display);
  color: rgba(238, 243, 246, 0.85);
  pointer-events: none;
  user-select: none;
}

/* Gravity: a small made-up shop page to knock over. */

.stage-gravity {
  background: #dfe6ec;
  color: #1c2731;
}

.mock {
  padding: clamp(18px, 4vw, 40px);
  display: grid;
  gap: 18px;
  align-content: start;
  max-width: 720px;
  font-size: 1.05rem;
}

.mock-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  align-items: baseline;
  font: 700 1.1rem/1 var(--display);
}

.mock-logo {
  margin-right: auto;
  font-size: 1.35rem;
}

.mock-bar a {
  color: #34505f;
  text-decoration: none;
}

.mock h3 {
  margin: 0;
  font: 900 clamp(1.8rem, 4.4vw, 3.2rem) / 1 var(--display);
}

.mock p {
  margin: 0;
  max-width: 34rem;
  color: #3d4f5c;
}

.mock-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.mock-row button {
  font: 700 1.05rem/1 var(--display);
  letter-spacing: 0.03em;
  padding: 11px 18px;
  border-radius: 8px;
  border: 2px solid #8a6d2b;
  background: #8a6d2b;
  color: #fff;
}

.mock-row button.ghost {
  background: transparent;
  color: #6b5320;
}

.mock-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.mock-tags span {
  font-size: 0.9rem;
  padding: 4px 12px;
  border-radius: 999px;
  background: #c9d5de;
}

.mock-tags .mock-badge {
  width: 46px;
  height: 46px;
  padding: 0;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, #f1d58f, #c4a35a 60%, #8a6d2b);
}

/* Dissolve: four specimens. */

.stage-dissolve {
  aspect-ratio: auto;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(12px, 2vw, 24px);
  padding: clamp(16px, 3vw, 32px);
  background: #101d28;
}

.specimen {
  display: grid;
  gap: 4px;
  align-content: start;
  text-align: left;
  padding: 0 0 16px;
  border: 0;
  border-radius: 12px;
  overflow: hidden;
  background: #e8eef3;
  color: #1c2731;
  font: inherit;
  cursor: pointer;
}

.specimen strong {
  padding: 12px 16px 0;
  font: 900 1.6rem/1 var(--display);
}

.specimen span:last-child {
  padding: 0 16px;
  font-size: 0.95rem;
  color: #46596a;
}

.art {
  display: block;
  aspect-ratio: 4 / 3;
}

.art-dust {
  background:
    radial-gradient(circle at 70% 30%, #f4e3b1 0 12%, transparent 13%),
    linear-gradient(160deg, #7d6aa8, #e48f6b 60%, #f6c58c);
}

.art-burn {
  background:
    linear-gradient(transparent 62%, #2b3a2f 62%),
    radial-gradient(circle at 30% 85%, #ffd27a, transparent 40%),
    linear-gradient(#b7d3e3, #f1e7c8);
}

.art-melt {
  background:
    radial-gradient(ellipse at 50% 120%, #2f6f86 0 45%, transparent 46%),
    linear-gradient(#e9f3f7, #9cc7d8);
}

.art-fade {
  background:
    radial-gradient(circle at 30% 40%, #9fc2a8 0 18%, transparent 19%),
    radial-gradient(circle at 68% 62%, #4f7f68 0 24%, transparent 25%),
    linear-gradient(135deg, #e2ecdf, #b9d0bd);
}

.plate-react .plate-body {
  margin-top: 0;
}

.footer {
  max-width: 1120px;
  margin: 72px auto 0;
  padding: 32px var(--gutter) 56px;
  border-top: 1px solid var(--line);
  color: var(--frost);
  display: grid;
  gap: 6px;
}

.footer p {
  margin: 0;
}

@media (max-width: 800px) {
  .plate {
    padding-block: 72px 16px;
  }

  .plate-body {
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
  }

  .stage {
    aspect-ratio: 4 / 3;
  }

  .stage-gravity {
    aspect-ratio: 4 / 5;
  }

  .stage-dissolve {
    aspect-ratio: auto;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .wordmark {
    padding-top: 22vh;
  }
}