/*
 * Alien-scapes.
 *
 * The page is a colour-viewing booth. Colour-assessment standards (ISO 3664)
 * put the thing being judged against a neutral grey surround, because any
 * tinted chrome biases the eye. So every surface here is an untinted grey, and
 * the only colour in the interface is the current star's own computed disk
 * colour, set from JavaScript as --accent.
 *
 * The computed colours sit in a flush strip under the landscape, like the
 * patches on a calibration target photographed with the scene.
 */

@font-face {
  font-family: "Atkinson Hyperlegible Next";
  src: url("fonts/atkinson-next-latin.woff2") format("woff2");
  font-weight: 200 800;
  font-display: swap;
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC,
    U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215,
    U+FEFF, U+FFFD;
}
@font-face {
  font-family: "Atkinson Hyperlegible Next";
  src: url("fonts/atkinson-next-latin-ext.woff2") format("woff2");
  font-weight: 200 800;
  font-display: swap;
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304,
    U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4,
    U+2113, U+2C60-2C7F, U+A720-A7FF;
}

:root {
  /* Neutral greys: R = G = B everywhere, so nothing tints the judgement. */
  --booth: #2a2a2a;
  --shelf: #323232;
  --rule: #444444;
  --ink: #eeeeee;
  --ink-2: #c4c4c4;
  --ink-3: #a3a3a3;
  --accent: #ffd8a8;
  --font: "Atkinson Hyperlegible Next", system-ui, -apple-system, "Segoe UI", sans-serif;
  color-scheme: dark;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--booth);
  color: var(--ink);
  font: 15px/1.55 var(--font);
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-underline-offset: 2px; }

/* ---------------------------------------------------------------- header */

.topbar {
  display: flex;
  align-items: center;
  gap: 14px 20px;
  padding: 16px 28px;
  flex-wrap: wrap;
  max-width: 1680px;
  margin: 0 auto;
}

.brand { display: flex; align-items: center; gap: 12px; }

/* The mark is the current star, lit by its own computed colour. */
.brand .mark {
  width: 24px; height: 24px; border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 18px -2px var(--accent);
  transition: background .4s, box-shadow .4s;
}

.topbar h1 {
  margin: 0;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.tagline { margin: 0; color: var(--ink-2); font-size: 14.5px; flex: 1; min-width: 240px; }

/* ---------------------------------------------------------------- layout */

.layout {
  display: grid;
  grid-template-columns: 320px minmax(0, 1fr);
  gap: 24px;
  padding: 4px 28px 64px;
  align-items: start;
  max-width: 1680px;
  margin: 0 auto;
}

.controls {
  background: var(--shelf);
  border-radius: 8px;
  padding: 2px 18px 18px;
  position: sticky;
  top: 16px;
  max-height: calc(100vh - 32px);
  overflow-y: auto;
  scrollbar-width: thin;
}

.stage { display: flex; flex-direction: column; gap: 28px; min-width: 0; }

/* ---------------------------------------------------------------- controls */

.group { padding: 16px 0; border-bottom: 1px solid var(--rule); }
.group:last-child { border-bottom: 0; }

.group h2 {
  margin: 0 0 10px;
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}

.sub { margin: 0 0 8px; font-size: 13px; color: var(--ink-3); }

.note {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--ink-3);
}

.field { display: block; margin-top: 14px; }

.field > span {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
  font-size: 13.5px;
  color: var(--ink-2);
  margin-bottom: 4px;
}

.field output {
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--ink);
}

select, input[type="text"] {
  width: 100%;
  padding: 8px 10px;
  background: var(--booth);
  color: var(--ink);
  border: 1px solid var(--rule);
  border-radius: 6px;
  font: inherit;
  font-size: 14px;
}

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

input[type="range"] {
  width: 100%;
  height: 24px;
  margin: 0;
  background: transparent;
  -webkit-appearance: none;
  appearance: none;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-runnable-track {
  height: 3px; border-radius: 2px; background: var(--rule);
}
input[type="range"]::-moz-range-track {
  height: 3px; border-radius: 2px; background: var(--rule);
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px; height: 16px; margin-top: -6.5px;
  border-radius: 50%; background: var(--accent);
  border: 2px solid var(--booth);
}
input[type="range"]::-moz-range-thumb {
  width: 14px; height: 14px;
  border-radius: 50%; background: var(--accent);
  border: 2px solid var(--booth);
}

button {
  font: inherit;
  font-size: 14px;
  padding: 8px 14px;
  border-radius: 6px;
  border: 1px solid transparent;
  background: var(--accent);
  color: #1a1a1a;
  font-weight: 600;
  cursor: pointer;
  transition: filter .15s;
}
button:hover { filter: brightness(1.08); }

button.ghost {
  background: transparent;
  color: var(--ink-2);
  border-color: var(--rule);
  font-weight: 500;
}
button.ghost:hover { color: var(--ink); border-color: var(--ink-3); filter: none; }

button.small { margin-top: 10px; padding: 6px 10px; font-size: 13px; width: 100%; }

/* star matrix: each button shows the class's own blackbody colour */

.starGrid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 4px;
}

.starGrid button {
  padding: 7px 2px 5px;
  font-size: 12px;
  background: var(--booth);
  border: 1px solid var(--rule);
  color: var(--ink-3);
  font-weight: 500;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
}

.starGrid button .dot {
  width: 12px; height: 12px; border-radius: 50%;
}

.starGrid button[aria-pressed="true"] {
  border-color: var(--accent);
  color: var(--ink);
  font-weight: 700;
}

.seedRow { display: flex; gap: 8px; }
.seedRow input { flex: 1; font-variant-numeric: tabular-nums; }
.seedRow button { margin-top: 0; width: auto; white-space: nowrap; }

/* habitable-zone bar */

.hzbar {
  position: relative;
  height: 6px;
  margin-top: 10px;
  border-radius: 3px;
  background: linear-gradient(90deg, #7a3a2e, #3a4a6e);
  overflow: hidden;
}
.hzbar .hzzone {
  position: absolute; top: 0; bottom: 0;
  background: rgba(130, 210, 150, 0.6);
}
.hzbar .hzmark {
  position: absolute; top: 0; bottom: 0;
  width: 2px; background: var(--ink);
}

/* ---------------------------------------------------------------- landscape */

.viewport {
  margin: 0;
  border-radius: 8px;
  overflow: hidden;
  background: #000;
}

.viewport canvas {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
}

/* The calibration strip: patches touch, with no gaps or rounding, so
   neighbouring colours are compared edge to edge. */
.strip {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  background: var(--shelf);
}

.patch { min-width: 0; padding-bottom: 10px; }
.patch .fill { height: 44px; }
.patch .lab {
  margin: 8px 12px 0;
  font-size: 13px;
  color: var(--ink-2);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.patch .hex {
  margin: 0 12px;
  font-size: 14px;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.viewport figcaption {
  padding: 10px 12px 12px;
  font-size: 13px;
  color: var(--ink-3);
  background: var(--shelf);
  border-top: 1px solid var(--rule);
}

/* ---------------------------------------------------------------- numbers */

.readout {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px 36px;
}

.readCol h3,
.exportBar h3 {
  margin: 0 0 8px;
  font-size: 15px;
  font-weight: 700;
}

.readCol dl {
  margin: 0;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0 12px;
}
.readCol dt, .readCol dd {
  padding: 4px 0;
  border-bottom: 1px solid var(--rule);
  font-size: 14px;
}
.readCol dt { color: var(--ink-2); }
.readCol dd {
  margin: 0;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  text-align: right;
}
.readCol dd.warn { color: #ffab80; }

.verdict { max-width: 76ch; }
.verdict p { margin: 0 0 8px; }
.verdict p:first-child { font-size: 18px; line-height: 1.45; font-weight: 600; }
.verdict p:last-child { margin-bottom: 0; }
.verdict .dim { color: var(--ink-2); font-size: 14.5px; }

/* ---------------------------------------------------------------- charts */

.tabs {
  display: flex;
  gap: 4px 22px;
  margin-bottom: 14px;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--rule);
}

.tab {
  background: transparent;
  border: 0;
  border-bottom: 2px solid transparent;
  border-radius: 0;
  margin-bottom: -1px;
  color: var(--ink-3);
  padding: 8px 0;
  font-size: 14.5px;
  font-weight: 600;
}
.tab:hover { color: var(--ink); filter: none; }
.tab.active { color: var(--ink); border-bottom-color: var(--accent); }

#chart { display: block; width: 100%; height: auto; aspect-ratio: 5 / 2; }

.charts .note { max-width: 80ch; }

/* ---------------------------------------------------------------- download */

.exportBar { border-top: 1px solid var(--rule); padding-top: 20px; }
.exportBar .note { max-width: 70ch; margin-top: 0; }

.btnRow { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; margin-top: 14px; }

/* The three formats are one choice, so they read as one joined control. */
.seg { display: inline-flex; align-items: stretch; }
.segLabel {
  display: flex; align-items: center;
  padding: 0 12px;
  font-size: 14px; font-weight: 600;
  border: 1px solid var(--rule);
  border-right: 0;
  border-radius: 6px 0 0 6px;
}
.seg button { border-radius: 0; border-left: 1px solid rgba(0, 0, 0, 0.25); }
.seg button:last-child { border-radius: 0 6px 6px 0; }

/* ---------------------------------------------------------------- dialog */

dialog {
  max-width: 640px;
  width: calc(100% - 32px);
  background: var(--shelf);
  color: var(--ink);
  border: 1px solid var(--rule);
  border-radius: 10px;
  padding: 0;
}
dialog::backdrop { background: rgba(20, 20, 20, 0.75); }
dialog article { padding: 24px 28px 22px; }
dialog h2 { margin: 0 0 12px; font-size: 22px; }
dialog h3 { margin: 20px 0 4px; font-size: 15px; }
dialog p { margin: 0 0 10px; font-size: 14.5px; color: var(--ink-2); max-width: 68ch; }
dialog form { margin-top: 18px; text-align: right; }

/* ---------------------------------------------------------------- narrow */

/* On narrow screens the landscape leads and stays pinned while the controls
   scroll beneath it, so every slider change is visible as it happens. */
@media (max-width: 1040px) {
  .topbar { padding: 14px 16px; }
  .layout { grid-template-columns: minmax(0, 1fr); gap: 20px; padding: 0 16px 48px; }
  .stage { display: contents; }
  .viewport {
    order: -1;
    position: sticky;
    top: 0;
    z-index: 5;
    border-radius: 0 0 8px 8px;
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.35);
  }
  .viewport figcaption { display: none; }
  .patch .fill { height: 14px; }
  .patch .lab { display: none; }
  .patch .hex { margin: 4px 8px 0; font-size: 12px; }
  .patch { padding-bottom: 6px; }
  .controls { position: static; max-height: none; }
}

@media (max-width: 640px) {
  #chart { aspect-ratio: 4 / 3; }
  .tabs { flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none; gap: 18px; }
  .tab { white-space: nowrap; font-size: 14px; }
}

@media (max-width: 1040px) and (max-height: 560px) {
  /* Landscape phones: pinning would cover most of the screen. */
  .viewport { position: static; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}