:root {
  --ink: #f2efe8;
  --dim: #9c988f;
  --faint: #5d5a55;
  --rule: rgb(242 239 232 / 0.14);
  --glass: rgb(12 12 14 / 0.62);
  --a: #5ec8ff;
  --b: #ff9d3c;
  --serif: "Instrument Serif", "Iowan Old Style", Georgia, serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --gutter: clamp(16px, 3vw, 36px);
  color-scheme: dark;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: #000;
  color: var(--ink);
  font: 13px/1.5 var(--mono);
  overflow: hidden;
}

#sky {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  cursor: grab;
  touch-action: none;
}
#sky:active { cursor: grabbing; }

/* --- wordmark ------------------------------------------------------------ */

.mark {
  position: fixed;
  top: var(--gutter);
  left: var(--gutter);
  pointer-events: none;
}
.mark h1 {
  margin: 0;
  font: 400 clamp(34px, 4.4vw, 56px)/0.9 var(--serif);
  letter-spacing: -0.01em;
}
.mark h1 em { color: var(--a); }
.mark p {
  margin: 10px 0 0;
  color: var(--dim);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* --- narrated caption ---------------------------------------------------- */

/* caption and engine note share one bottom stack, so they never collide */
.foot {
  position: fixed;
  left: var(--gutter);
  right: var(--gutter);
  bottom: var(--gutter);
  display: flex;
  flex-direction: column;
  gap: 18px;
  pointer-events: none;
}
.caption { max-width: min(560px, 52vw); }
.caption .phase {
  margin: 0 0 8px;
  color: var(--dim);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.caption .phase #phase-no { color: var(--b); }
.caption .line {
  margin: 0;
  font: 400 clamp(24px, 2.6vw, 34px)/1.15 var(--serif);
  text-wrap: balance;
  transition: opacity 0.6s ease;
}
.caption .line.swap { opacity: 0; }

/* --- console ------------------------------------------------------------- */

.console {
  position: fixed;
  top: var(--gutter);
  right: var(--gutter);
  width: 272px;
  max-height: calc(100% - 2 * var(--gutter) - 52px);
  overflow: auto;
  background: var(--glass);
  backdrop-filter: blur(14px) saturate(1.2);
  -webkit-backdrop-filter: blur(14px) saturate(1.2);
  border: 1px solid var(--rule);
  border-radius: 14px;
}
.console details { padding: 0 16px 14px; }
.console summary {
  list-style: none;
  cursor: pointer;
  padding: 14px 0 10px;
  color: var(--dim);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  display: flex;
  justify-content: space-between;
}
.console summary::-webkit-details-marker { display: none; }
.console summary::after { content: "–"; }
.console details:not([open]) { padding-bottom: 0; }
.console details:not([open]) summary::after { content: "+"; }

.readouts { margin: 0 0 14px; border-top: 1px solid var(--rule); }
.readouts div {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 6px 0;
  border-bottom: 1px solid var(--rule);
}
.readouts dt { color: var(--dim); }
.readouts dd { margin: 0; font-variant-numeric: tabular-nums; }

button, .seg span {
  font: inherit;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 5px 12px;
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
}
button:hover, .seg label:hover span { border-color: rgb(242 239 232 / 0.4); }
button:focus-visible, .seg input:focus-visible + span, input[type="range"]:focus-visible {
  outline: 2px solid var(--a);
  outline-offset: 2px;
}

.transport { display: flex; gap: 8px; margin-bottom: 14px; }
.transport button { flex: 1; }

.seg {
  border: 0;
  margin: 0 0 12px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.seg legend {
  padding: 0;
  margin-bottom: 6px;
  color: var(--dim);
  font-size: 11px;
}
.seg label { display: contents; }
.seg input { position: absolute; opacity: 0; pointer-events: none; }
.seg span, .seg button { flex: 1; text-align: center; padding: 5px 0; }
.seg input:checked + span { background: var(--ink); color: #000; border-color: var(--ink); }
.seg button[aria-pressed="true"] { background: var(--ink); color: #000; border-color: var(--ink); }

.slider { display: block; margin: 0 0 12px; }
.slider span {
  display: flex;
  justify-content: space-between;
  color: var(--dim);
  font-size: 11px;
}
.slider output { color: var(--ink); font-variant-numeric: tabular-nums; }
input[type="range"] {
  width: 100%;
  margin: 6px 0 0;
  accent-color: var(--b);
}

/* --- engine strip ------------------------------------------------------- */

.engine {
  pointer-events: auto;
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--rule);
  color: var(--dim);
  font-size: 12px;
}
.engine p { margin: 0; max-width: calc(100vw - 2 * var(--gutter) - 300px); }
.engine strong { color: var(--ink); font-weight: 500; }
.engine a { color: var(--ink); text-underline-offset: 3px; }

/* --- no WebGPU ----------------------------------------------------------- */

.fallback {
  position: fixed;
  inset: 0;
  display: grid;
  place-content: center;
  gap: 18px;
  padding: var(--gutter);
  background: #000;
  text-align: center;
}
.fallback[hidden] { display: none; }
.fallback img { max-width: min(560px, 100%); margin: 0 auto; border-radius: 10px; }
.fallback p { max-width: 52ch; margin: 0 auto; color: var(--dim); }

/* --- small screens: console spans the width under the wordmark ---------- */

@media (max-width: 720px) {
  .console {
    top: calc(var(--gutter) + 82px);
    left: var(--gutter);
    right: var(--gutter);
    width: auto;
    max-height: 60vh;
  }
  .caption { max-width: none; }
  .caption .line { font-size: 22px; }
  .engine { font-size: 11px; }
  .engine p { max-width: none; }
}

@media (prefers-reduced-motion: reduce) {
  .caption .line { transition: none; }
}