/* Night Notes. Layout: one quiet column of night bands (max 1120px); text on
   the left, instruments (moon, chart, spectrum) beside or below it. */
:root {
  --sky: #04060c;
  --sky-raised: #0b1020;
  --line: rgba(169, 193, 255, 0.13);
  --text: #e9edf7;
  --muted: #8d97b1;
  --accent: #a9c1ff;
  --warm: #ffd2a1;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI Variable Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-display: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI Variable Display", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
  --radius: 22px;
  --wrap: 1120px;
  --gutter-l: max(20px, env(safe-area-inset-left, 0px));
  --gutter-r: max(20px, env(safe-area-inset-right, 0px));
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { background: var(--sky); -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 72px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--sky);
  color: var(--text);
  font: 17px/1.55 var(--font);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding-left: var(--gutter-l);
  padding-right: var(--gutter-r);
}

/* Bar */
body::before {
  content: "";
  position: fixed;
  inset: 0 0 auto;
  height: env(safe-area-inset-top, 0px);
  z-index: 30;
  background: var(--sky);
}
.bar {
  position: sticky;
  top: env(safe-area-inset-top, 0px);
  z-index: 20;
  background: rgba(4, 6, 12, 0.72);
  -webkit-backdrop-filter: saturate(160%) blur(18px);
  backdrop-filter: saturate(160%) blur(18px);
  border-bottom: 1px solid var(--line);
}
.bar-in {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--gutter-r) 0 var(--gutter-l);
  height: 52px;
  display: flex;
  align-items: center;
  gap: 28px;
}
.mark {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--text);
  font: 600 16px/1 var(--font-display);
  letter-spacing: -0.01em;
}
.mark:hover { text-decoration: none; }
.mark-star {
  width: 13px;
  height: 13px;
  background: var(--text);
  clip-path: polygon(50% 0, 61% 39%, 100% 50%, 61% 61%, 50% 100%, 39% 61%, 0 50%, 39% 39%);
}
.links { display: flex; gap: 22px; margin-left: auto; }
.links a { color: var(--muted); font-size: 14px; }
.links a:hover { color: var(--text); text-decoration: none; }
.red-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 13px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--text);
  font: 500 13px/1 var(--font);
  cursor: pointer;
}
.red-toggle:hover { border-color: rgba(169, 193, 255, 0.35); }
.red-dot { width: 8px; height: 8px; border-radius: 50%; background: #ff3b2f; box-shadow: 0 0 8px #ff3b2f; }
.red-toggle[aria-pressed="true"] { background: rgba(255, 59, 47, 0.16); border-color: rgba(255, 59, 47, 0.5); }

/* Red light: everything collapses into the red channel, like a red flashlight.
   No filter on body here: it would isolate the layer, and the overlay would
   blend with nothing instead of the dark page. */
html.red body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 100;
  pointer-events: none;
  background: #d92a18;
  mix-blend-mode: multiply;
}

/* Type */
.eyebrow {
  margin: 0 0 14px;
  color: var(--muted);
  font: 600 13px/1.2 var(--font);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
h1, h2, h3 { font-family: var(--font-display); text-wrap: balance; margin: 0; }
h2 {
  font-size: clamp(30px, 4.6vw, 52px);
  line-height: 1.06;
  font-weight: 700;
  letter-spacing: -0.028em;
  max-width: 20ch;
}
h3 { font-size: 19px; font-weight: 600; letter-spacing: -0.01em; }
.lead {
  margin: 20px 0 0;
  max-width: 62ch;
  color: var(--muted);
  font-size: clamp(17px, 1.6vw, 20px);
  line-height: 1.5;
}
.note { margin: 28px 0 0; max-width: 62ch; color: var(--muted); font-size: 15px; }
p { margin: 0; }

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  padding-block: clamp(64px, 11vw, 140px) clamp(56px, 8vw, 104px);
  border-bottom: 1px solid var(--line);
  /* A faint Milky Way band and the glow of a sky that is never quite black. */
  background:
    radial-gradient(ellipse 55% 45% at 82% 18%, rgba(98, 120, 200, 0.16), transparent 70%),
    linear-gradient(118deg, transparent 28%, rgba(150, 160, 210, 0.05) 40%, rgba(205, 190, 225, 0.085) 49%, rgba(150, 160, 210, 0.05) 58%, transparent 72%),
    var(--sky);
}
.sky {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}
.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 40%;
  background: linear-gradient(to bottom, transparent, var(--sky));
  pointer-events: none;
}
.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr);
  gap: clamp(32px, 6vw, 88px);
  align-items: end;
}
h1 {
  font-size: clamp(64px, 13vw, 156px);
  line-height: 0.92;
  font-weight: 800;
  letter-spacing: -0.055em;
  margin-left: -0.04em;
}
h1 .dot { color: var(--warm); }
.hero .lead { color: #b5bdd2; max-width: 30ch; margin-top: 26px; }

.tonight {
  min-width: 0;
  padding: 26px 26px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(11, 16, 32, 0.62);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
}
.tonight-title {
  font: 600 13px/1.2 var(--font);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}
.moon-row { display: flex; align-items: center; gap: 20px; margin-top: 18px; }
.moon { width: 84px; height: 84px; flex: none; }
.moon-dark { fill: #161c2c; }
.moon-lit { fill: #f1eee4; }
.moon-phase { font: 600 22px/1.2 var(--font-display); letter-spacing: -0.015em; }
.moon-meta { margin-top: 4px; color: var(--muted); font-size: 15px; font-variant-numeric: tabular-nums; }
.facts { margin: 22px 0 0; display: grid; gap: 0; }
.facts div {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 0;
  border-top: 1px solid var(--line);
  font-size: 15px;
}
.facts dt { color: var(--muted); }
.facts dd { margin: 0; text-align: right; font-variant-numeric: tabular-nums; }
.fine { margin-top: 10px; color: var(--muted); font-size: 12px; line-height: 1.45; opacity: 0.8; }

/* Bands */
.band { padding-block: clamp(72px, 10vw, 128px); border-bottom: 1px solid var(--line); }

/* Spectrum */
.spectrum {
  list-style: none;
  margin: 48px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 12px;
}
.spectrum li { display: grid; gap: 6px; min-width: 0; }
.spectrum .sw {
  height: 132px;
  border-radius: 16px;
  background:
    radial-gradient(circle at 50% 38%, #fff 0, var(--c) 18%, transparent 62%),
    linear-gradient(180deg, color-mix(in srgb, var(--c) 22%, transparent), transparent);
  border: 1px solid color-mix(in srgb, var(--c) 30%, transparent);
  margin-bottom: 8px;
}
.spectrum b { font: 700 28px/1 var(--font-display); color: var(--c); letter-spacing: -0.02em; }
.spectrum .t { font: 500 13px/1.3 var(--font-mono); color: var(--text); font-variant-numeric: tabular-nums; }
.spectrum .ex { font-size: 14px; color: var(--muted); }

/* Polaris */
.split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(32px, 6vw, 80px);
  align-items: center;
}
.split-copy { min-width: 0; display: grid; gap: 18px; }
.split-copy > p { color: var(--muted); max-width: 52ch; }
.split-copy h2 { margin-bottom: 4px; }
.lat {
  margin-top: 10px;
  padding: 20px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--sky-raised);
  display: grid;
  gap: 12px;
}
.lat label { display: flex; justify-content: space-between; font-weight: 600; font-size: 15px; }
.lat output { color: var(--accent); font-variant-numeric: tabular-nums; }
.lat input[type="range"] { width: 100%; accent-color: var(--accent); }
.lat-text { color: var(--muted); font-size: 15px; }
.circum { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.circum li {
  padding: 5px 11px;
  border-radius: 999px;
  font-size: 13px;
  border: 1px solid var(--line);
  color: var(--muted);
}
.circum li.up { color: var(--text); border-color: rgba(169, 193, 255, 0.4); background: rgba(169, 193, 255, 0.08); }
.circum li::before { content: "Sets · "; color: var(--muted); }
.circum li.up::before { content: "Never sets · "; color: var(--accent); }

.chart { margin: 0; min-width: 0; }
.chart svg {
  display: block;
  width: 100%;
  max-width: 520px;
  aspect-ratio: 1;
  margin: 0 auto;
  border-radius: 50%;
  background: radial-gradient(circle, #0d1428 0%, #070b16 70%, var(--sky) 100%);
  box-shadow: inset 0 0 0 1px var(--line);
}
.chart figcaption { margin: 16px auto 0; max-width: 46ch; text-align: center; color: var(--muted); font-size: 13px; }
.chart .grid { fill: none; stroke: rgba(169, 193, 255, 0.08); stroke-width: 0.4; }
.chart .limit { fill: rgba(169, 193, 255, 0.05); stroke: var(--accent); stroke-width: 0.6; stroke-dasharray: 2 2; transition: r 0.25s ease; }
.chart .fig { fill: none; stroke: rgba(233, 237, 247, 0.32); stroke-width: 0.55; }
.chart .pointer { fill: none; stroke: var(--warm); stroke-width: 0.6; stroke-dasharray: 1.6 1.6; }
.chart .star { fill: #f4f6ff; }
.chart .bg { fill: #c9d2ee; }
.chart .lbl { fill: var(--muted); font: 500 4.2px var(--font); }
.chart .lbl-c { fill: var(--text); font: 600 4.6px var(--font); letter-spacing: 0.04em; }
.chart .lbl-p { fill: var(--warm); font: 600 4.8px var(--font); }
@media (prefers-reduced-motion: reduce) { .chart .limit { transition: none; } }

/* Light travel */
.ages {
  margin-top: 48px;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  border-top: 1px solid var(--line);
}
.ages div { padding: 24px 16px 0 0; display: grid; gap: 6px; min-width: 0; }
.ages b {
  font: 700 clamp(30px, 4vw, 46px)/1 var(--font-display);
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
}
.ages small { font-size: 0.45em; font-weight: 600; color: var(--muted); letter-spacing: 0; }
.ages span { color: var(--muted); font-size: 15px; }

/* Life of a star */
.tracks { margin-top: 48px; display: grid; gap: 40px; }
.track h3 { margin-bottom: 18px; }
.track ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
  counter-reset: step;
}
.track li {
  position: relative;
  min-width: 0;
  padding: 18px 16px 18px;
  border-radius: 16px;
  background: var(--sky-raised);
  border: 1px solid var(--line);
  display: grid;
  gap: 6px;
  align-content: start;
}
.track li::before {
  counter-increment: step;
  content: counter(step);
  font: 600 12px/1 var(--font-mono);
  color: var(--muted);
}
.track b { font: 600 16px/1.25 var(--font-display); }
.track span { color: var(--muted); font-size: 14px; line-height: 1.4; }
.track li:last-child { border-color: rgba(255, 210, 161, 0.35); }
.heavy li:last-child { border-color: rgba(169, 193, 255, 0.4); }

/* Showers */
.table-scroll { margin-top: 44px; overflow-x: auto; }
.showers { width: 100%; min-width: 560px; border-collapse: collapse; font-size: 16px; }
.showers th, .showers td { text-align: left; padding: 15px 16px 15px 0; border-bottom: 1px solid var(--line); }
.showers thead th { color: var(--muted); font-size: 13px; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; }
.showers tbody th { font-weight: 600; }
.showers td { color: var(--muted); }
.showers .num { text-align: right; padding-right: 40px; font-variant-numeric: tabular-nums; color: var(--text); }
.showers tr.next th, .showers tr.next td { color: var(--text); }
.showers tr.next th::after {
  content: attr(data-when);
  margin-left: 10px;
  padding: 3px 9px;
  border-radius: 999px;
  background: rgba(255, 210, 161, 0.14);
  color: var(--warm);
  font-size: 12px;
  font-weight: 600;
  white-space: nowrap;
}

/* Bortle */
.bortle {
  list-style: none;
  margin: 48px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(9, minmax(0, 1fr));
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
}
.bortle li {
  min-width: 0;
  padding: 18px 12px 16px;
  display: grid;
  gap: 6px;
  align-content: start;
  min-height: 150px;
  background: color-mix(in srgb, #3b3346 calc(var(--g) * 11%), #03050a);
}
.bortle b { font: 700 26px/1 var(--font-display); }
.bortle span { font-size: 13px; line-height: 1.3; color: #c3c9da; }
.bortle em { margin-top: auto; font: 500 12px/1.2 var(--font-mono); font-style: normal; color: var(--muted); }

.tips {
  margin-top: 56px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(24px, 4vw, 48px);
}
.tips div { min-width: 0; display: grid; gap: 8px; align-content: start; }
.tips p { color: var(--muted); font-size: 15px; }

/* Footer */
.foot { padding-block: 36px 48px; }
.foot-in { display: flex; flex-wrap: wrap; gap: 12px 28px; align-items: center; color: var(--muted); font-size: 13px; }
.mark.small { font-size: 14px; }

/* 404 */
.lost { padding-block: clamp(96px, 16vw, 200px); }
.lost h1 { font-size: clamp(56px, 10vw, 120px); }
.lost .lead { max-width: 40ch; }
.lost .coords { margin-top: 28px; font: 500 14px/1.4 var(--font-mono); color: var(--warm); }
.lost .home-link { display: inline-block; margin-top: 28px; font-weight: 600; }

/* Narrow screens */
@media (max-width: 900px) {
  .hero-grid, .split { grid-template-columns: minmax(0, 1fr); }
  .hero .lead { max-width: 40ch; }
  .spectrum { grid-template-columns: repeat(4, minmax(0, 1fr)); row-gap: 24px; }
  .ages { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .track ol { grid-template-columns: minmax(0, 1fr); }
  .track li { grid-template-columns: 22px minmax(0, 1fr); column-gap: 10px; }
  .track li::before { grid-row: span 2; padding-top: 3px; }
  .bortle { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .bortle li { min-height: 120px; }
  .tips { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 640px) {
  .links { display: none; }
  .red-toggle { margin-left: auto; }
  .spectrum { grid-template-columns: minmax(0, 1fr); gap: 10px; }
  .spectrum li { grid-template-columns: 48px 36px minmax(0, 1fr); align-items: center; column-gap: 12px; }
  .spectrum .sw { height: 48px; margin: 0; grid-row: span 2; border-radius: 12px; }
  .spectrum b { grid-row: span 2; font-size: 24px; }
  .spectrum .t, .spectrum .ex { grid-column: 3; }
  .ages { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .facts div { flex-direction: column; gap: 2px; }
  .facts dd { text-align: left; }
  .chart .lbl { font-size: 5.6px; }
  .chart .lbl-c { font-size: 5.8px; }
  .chart .lbl-p { font-size: 6.2px; }
}