/* Aether Field — fully offline. System fonts only. */

:root {
  --color-void: #02040a;
  --color-surface: #05070c;
  --color-raised: #0b1018;
  --color-raised-2: #121a26;
  --color-border: color-mix(in oklab, white 10%, transparent);
  --color-border-strong: color-mix(in oklab, white 18%, transparent);
  --color-text: #e8eef7;
  --color-muted: #93a0b5;
  --color-primary: #5eead4;
  --color-primary-ink: #042f2e;
  --color-secondary: #f0abfc;
  --color-amber: #fbbf24;
  --color-phosphor: #67e8f9;
  --color-danger: #fb7185;

  --font-display: ui-sans-serif, system-ui, -apple-system, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --font-body: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", "Cascadia Code", "Segoe UI Mono", Menlo, Consolas, monospace;

  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 32px;
  --space-xl: 64px;
  --space-2xl: 96px;

  --radius-sm: 4px;
  --radius-md: 10px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  --nav-h: 64px;
  --content: min(72rem, calc(100% - 2 * var(--space-lg)));
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --focus: 0 0 0 2px var(--color-void), 0 0 0 4px var(--color-primary);

  color-scheme: dark;
  --scroll-p: 0;
  --field-opacity: 0.85;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 12px);
}

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

body {
  margin: 0;
  min-height: 100%;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-void);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img,
svg,
canvas {
  display: block;
  max-width: 100%;
}

a {
  color: var(--color-primary);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover {
  color: color-mix(in oklab, var(--color-primary) 80%, white);
}

:focus-visible {
  outline: none;
  box-shadow: var(--focus);
}

.skip-link {
  position: absolute;
  left: var(--space-md);
  top: -100px;
  z-index: 100;
  padding: 0.6rem 1rem;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  text-decoration: none;
}

.skip-link:focus {
  top: var(--space-md);
}

/* —— Field layer —— */
.field-layer {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}

#field-canvas {
  width: 100%;
  height: 100%;
  opacity: var(--field-opacity);
}

.field-fallback {
  position: absolute;
  inset: 0;
  display: none;
  background:
    radial-gradient(ellipse 80% 60% at 20% 30%, color-mix(in oklab, var(--color-phosphor) 28%, transparent), transparent 55%),
    radial-gradient(ellipse 70% 50% at 80% 70%, color-mix(in oklab, var(--color-secondary) 18%, transparent), transparent 50%),
    radial-gradient(ellipse 50% 40% at 50% 100%, color-mix(in oklab, var(--color-primary) 14%, transparent), transparent 60%),
    linear-gradient(165deg, #05070c 0%, #0a1220 45%, #05070c 100%);
}

.field-fallback.is-active {
  display: block;
}

body.is-still .field-fallback {
  animation: none;
}

.field-vignette {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 60% at 50% 40%, transparent 0%, color-mix(in oklab, var(--color-void) 55%, transparent) 100%),
    linear-gradient(to bottom, color-mix(in oklab, var(--color-void) 20%, transparent), var(--color-void) 96%);
}

/* —— Nav —— */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(14px) saturate(1.2);
  -webkit-backdrop-filter: blur(14px) saturate(1.2);
  background: color-mix(in oklab, var(--color-void) 72%, transparent);
  border-bottom: 1px solid var(--color-border);
}

.nav-inner {
  width: var(--content);
  margin: 0 auto;
  min-height: var(--nav-h);
  display: flex;
  align-items: center;
  gap: var(--space-md);
  justify-content: space-between;
}

.nav-mark {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text);
  text-decoration: none;
  white-space: nowrap;
}

.nav-mark-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-primary);
  box-shadow: 0 0 12px color-mix(in oklab, var(--color-primary) 80%, transparent);
}

.nav-links {
  display: none;
  gap: 0.35rem 1rem;
  flex-wrap: wrap;
  justify-content: center;
}

.nav-links a {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-muted);
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a[aria-current="true"] {
  color: var(--color-text);
}

.nav-meta {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.badge {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.35rem 0.55rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-strong);
  color: var(--color-primary);
  background: color-mix(in oklab, var(--color-primary) 8%, transparent);
  white-space: nowrap;
}

.progress {
  height: 2px;
  background: color-mix(in oklab, white 6%, transparent);
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-phosphor));
  transform-origin: left center;
}

/* —— Buttons —— */
.btn-primary,
.btn-ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0.65rem 1.15rem;
  border-radius: var(--radius-full);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 160ms var(--ease-out), background 160ms ease, border-color 160ms ease, color 160ms ease;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.btn-primary:hover {
  background: color-mix(in oklab, var(--color-primary) 85%, white);
  color: var(--color-primary-ink);
}

.btn-ghost {
  background: color-mix(in oklab, white 4%, transparent);
  border-color: var(--color-border-strong);
  color: var(--color-text);
}

.btn-ghost:hover,
.btn-ghost[aria-pressed="true"] {
  border-color: color-mix(in oklab, var(--color-primary) 50%, transparent);
  color: var(--color-primary);
}

.btn-primary:active,
.btn-ghost:active {
  transform: translateY(1px);
}

/* —— Main sections —— */
main {
  position: relative;
  z-index: 1;
}

.hero,
.section,
.footer {
  width: var(--content);
  margin-inline: auto;
}

.hero {
  min-height: calc(100svh - var(--nav-h));
  display: grid;
  align-content: center;
  padding: var(--space-xl) 0 var(--space-2xl);
  position: relative;
}

.hero-grid {
  max-width: 46rem;
}

.kicker {
  margin: 0 0 var(--space-md);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-primary);
}

h1,
h2,
h3 {
  font-family: var(--font-display);
  font-weight: 750;
  letter-spacing: -0.02em;
  line-height: 1.08;
  margin: 0 0 var(--space-md);
  text-wrap: balance;
}

h1 {
  font-size: clamp(2.6rem, 7vw, 4.75rem);
  line-height: 0.96;
  margin-bottom: var(--space-lg);
}

.hero-line {
  display: block;
}

.hero-line-em {
  background: linear-gradient(
    105deg,
    var(--color-text) 0%,
    var(--color-phosphor) 45%,
    var(--color-secondary) 78%,
    var(--color-text) 100%
  );
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lead,
.lede {
  max-width: 40rem;
  color: var(--color-muted);
  font-size: clamp(1.02rem, 1.5vw, 1.15rem);
  margin: 0 0 var(--space-lg);
}

.hero-lead em {
  color: var(--color-text);
  font-style: normal;
  border-bottom: 1px solid color-mix(in oklab, var(--color-primary) 50%, transparent);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-md);
  margin: 0;
  padding: var(--space-md) 0 0;
  border-top: 1px solid var(--color-border);
}

.hero-stats dt {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 0.25rem;
}

.hero-stats dd {
  margin: 0;
  font-size: 0.92rem;
  color: var(--color-text);
}

.hero-scroll-hint {
  position: absolute;
  left: 0;
  bottom: var(--space-lg);
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-muted);
  opacity: 0.75;
}

.section {
  padding: var(--space-2xl) 0;
}

.section-head {
  max-width: 40rem;
  margin-bottom: var(--space-xl);
}

.section-head h2,
.split-copy h2 {
  font-size: clamp(1.85rem, 4vw, 2.6rem);
}

/* Orient */
.orient-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
}

.orient-card {
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  background: color-mix(in oklab, var(--color-raised) 88%, transparent);
  backdrop-filter: blur(8px);
}

.orient-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-primary);
  margin-bottom: var(--space-sm);
}

.orient-card h3 {
  font-size: 1.25rem;
  margin-bottom: var(--space-sm);
}

.orient-card p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.98rem;
}

/* Split specimens */
.section-split {
  display: grid;
  gap: var(--space-xl);
  align-items: center;
}

.split-copy p {
  color: var(--color-muted);
}

.split-copy strong {
  color: var(--color-text);
  font-weight: 600;
}

.spec-list {
  margin: var(--space-lg) 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.55rem;
}

.spec-list li {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-text);
  padding: 0.55rem 0.75rem;
  border-left: 2px solid var(--color-primary);
  background: color-mix(in oklab, var(--color-raised) 80%, transparent);
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  color: var(--color-phosphor);
}

.caption {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-muted);
  letter-spacing: 0.02em;
}

.specimen {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: color-mix(in oklab, var(--color-raised) 92%, transparent);
  backdrop-filter: blur(10px);
  overflow: hidden;
  container-type: inline-size;
  container-name: specimen;
}

.stage-chrome {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 0.9rem;
  border-bottom: 1px solid var(--color-border);
  background: color-mix(in oklab, black 20%, transparent);
}

.stage-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-primary);
  box-shadow: 0 0 8px var(--color-primary);
}

.stage-title {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-muted);
  letter-spacing: 0.04em;
}

#light-mini {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  background: #03050a;
}

.split-stage figcaption,
.specimen > .caption,
.anchor-demo > .caption {
  margin: 0;
  padding: 0.75rem 1rem 1rem;
}

/* Timeline */
.timeline-wrap {
  margin: 0 calc(50% - 50vw);
  padding: 0 max(var(--space-lg), calc((100vw - 72rem) / 2));
}

.timeline-track {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(240px, 78vw);
  gap: var(--space-md);
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x mandatory;
  padding-bottom: var(--space-md);
  scrollbar-color: var(--color-primary) transparent;
}

.timeline-track:focus-visible {
  box-shadow: var(--focus);
  border-radius: var(--radius-md);
}

.tl-card {
  scroll-snap-align: start;
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  background: color-mix(in oklab, var(--color-raised) 90%, transparent);
  min-height: 220px;
  display: flex;
  flex-direction: column;
}

.tl-card time {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-primary);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.tl-card h3 {
  font-size: 1.35rem;
  margin: 0.5rem 0;
}

.tl-card p {
  margin: 0 0 auto;
  color: var(--color-muted);
  font-size: 0.95rem;
}

.tl-bar {
  margin-top: var(--space-lg);
  height: 4px;
  border-radius: var(--radius-full);
  background: color-mix(in oklab, white 8%, transparent);
  position: relative;
  overflow: hidden;
}

.tl-bar::after {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: calc(var(--p, 0.5) * 100%);
  border-radius: inherit;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
}

/* Scroll-driven enhancement when supported */
@supports (animation-timeline: view()) {
  .tl-bar::after {
    width: 100%;
    transform: scaleX(var(--p, 0.5));
    transform-origin: left center;
  }

  .reveal {
    animation: rise-in linear both;
    animation-timeline: view();
    animation-range: entry 0% cover 28%;
  }
}

@keyframes rise-in {
  from {
    opacity: 0.2;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.callout {
  margin-top: var(--space-xl);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  border: 1px solid color-mix(in oklab, var(--color-amber) 35%, transparent);
  background: color-mix(in oklab, var(--color-amber) 8%, var(--color-raised));
  max-width: 44rem;
}

.callout-label {
  margin: 0 0 0.4rem;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-amber);
}

.callout p:last-child {
  margin: 0;
  color: var(--color-text);
}

/* Anchor demo */
.anchor-demo {
  padding-bottom: var(--space-md);
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  padding: var(--space-lg);
}

.chip {
  min-height: 44px;
  padding: 0.55rem 1rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--color-border-strong);
  background: color-mix(in oklab, white 4%, transparent);
  color: var(--color-text);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  cursor: pointer;
}

.chip:hover,
.chip:focus-visible,
.chip.is-active {
  border-color: color-mix(in oklab, var(--color-primary) 60%, transparent);
  color: var(--color-primary);
  background: color-mix(in oklab, var(--color-primary) 10%, transparent);
}

.chip-note {
  margin: 0 var(--space-lg) var(--space-md);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-raised-2);
}

.chip-note strong {
  display: block;
  font-family: var(--font-display);
  font-size: 1.05rem;
  margin-bottom: 0.35rem;
}

.chip-note p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.95rem;
}

/* Progressive anchor positioning */
@supports (anchor-name: --x) {
  .chip-note {
    position: absolute;
    position-anchor: --chip-a;
    bottom: anchor(top);
    left: anchor(left);
    margin-bottom: 8px;
    width: min(280px, 80%);
    z-index: 2;
  }

  .anchor-demo {
    position: relative;
    min-height: 280px;
  }

  .chip-note[data-active="b"] {
    position-anchor: --chip-b;
  }

  .chip-note[data-active="c"] {
    position-anchor: --chip-c;
  }
}

/* Continuity / tabs */
.vt-demo {
  max-width: 44rem;
}

.vt-tabs {
  display: flex;
  gap: 0.25rem;
  padding: 0.5rem;
  border-bottom: 1px solid var(--color-border);
  background: color-mix(in oklab, black 15%, transparent);
}

.vt-tabs [role="tab"] {
  flex: 1;
  min-height: 44px;
  border: 0;
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--color-muted);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  cursor: pointer;
}

.vt-tabs [role="tab"][aria-selected="true"] {
  background: color-mix(in oklab, var(--color-primary) 14%, transparent);
  color: var(--color-primary);
}

.vt-panels {
  padding: var(--space-lg);
  min-height: 10rem;
}

.vt-panel h3 {
  font-size: 1.35rem;
}

.vt-panel p {
  margin: 0;
  color: var(--color-muted);
}

::view-transition-old(vt-panel),
::view-transition-new(vt-panel) {
  animation-duration: 280ms;
  animation-timing-function: var(--ease-out);
}

.vt-panel[data-vt="panel"] {
  view-transition-name: vt-panel;
}

/* Lab */
.lab-grid {
  display: grid;
  gap: var(--space-lg);
}

.lab-controls {
  padding: var(--space-lg);
  display: grid;
  gap: var(--space-md);
}

.lab-row {
  display: grid;
  grid-template-columns: 5.5rem 1fr 3rem;
  gap: var(--space-sm);
  align-items: center;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--color-muted);
}

.lab-row input[type="range"] {
  width: 100%;
  accent-color: var(--color-primary);
  height: 44px;
}

.lab-row output {
  text-align: right;
  color: var(--color-primary);
  font-variant-numeric: tabular-nums;
}

.lab-readout {
  padding: var(--space-lg);
}

.lab-readout h3 {
  font-size: 1.2rem;
}

.lab-readout ul {
  margin: 0 0 var(--space-md);
  padding-left: 1.1rem;
  color: var(--color-muted);
}

.lab-readout li {
  margin-bottom: 0.4rem;
}

.code-block {
  margin: 0;
  padding: var(--space-md);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: color-mix(in oklab, black 35%, var(--color-raised));
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.5;
  color: var(--color-phosphor);
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-word;
}

/* Principles */
.principles-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--space-md);
  max-width: 48rem;
}

.principles-list li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--space-md);
  padding: var(--space-lg) 0;
  border-top: 1px solid var(--color-border);
}

.p-num {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 600;
  color: color-mix(in oklab, var(--color-primary) 70%, white);
  line-height: 1;
  min-width: 2.5rem;
}

.principles-list h3 {
  font-size: 1.25rem;
  margin-bottom: 0.35rem;
}

.principles-list p {
  margin: 0;
  color: var(--color-muted);
}

/* Footer */
.footer {
  padding: var(--space-2xl) 0 var(--space-xl);
  border-top: 1px solid var(--color-border);
  margin-top: var(--space-xl);
}

.footer-grid {
  display: grid;
  gap: var(--space-xl);
}

.footer-tag,
.footer-path,
.footer p {
  color: var(--color-muted);
  font-size: 0.95rem;
}

/* Reveal fallback via JS class when no scroll-driven support */
body:not(.has-view-timeline) .reveal {
  opacity: 0.15;
  transform: translateY(16px);
  transition: opacity 500ms var(--ease-out), transform 500ms var(--ease-out);
}

body:not(.has-view-timeline) .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* —— Responsive —— */
@media (min-width: 720px) {
  .nav-links {
    display: flex;
  }

  .orient-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .timeline-track {
    grid-auto-columns: minmax(280px, 320px);
  }

  .lab-grid {
    grid-template-columns: 1.1fr 0.9fr;
  }

  .footer-grid {
    grid-template-columns: 1.2fr 1fr 1fr;
  }
}

@media (min-width: 960px) {
  .section-split {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-2xl);
  }

  .section-split.reverse .split-copy {
    order: 2;
  }

  .section-split.reverse .split-stage {
    order: 1;
  }

  .orient-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 719px) {
  :root {
    --content: min(72rem, calc(100% - 2 * var(--space-md)));
  }

  .nav-meta .badge {
    display: none;
  }

  .hero-stats {
    grid-template-columns: 1fr;
  }

  .lab-row {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }

  .lab-row output {
    text-align: left;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .reveal {
    animation: none !important;
    opacity: 1 !important;
    transform: none !important;
  }

  body:not(.has-view-timeline) .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .btn-primary,
  .btn-ghost {
    transition: none;
  }

  ::view-transition-old(vt-panel),
  ::view-transition-new(vt-panel) {
    animation: none !important;
  }
}

body.is-still .reveal {
  animation: none !important;
  opacity: 1 !important;
  transform: none !important;
  transition: none !important;
}

/* Container query: denser stage labels when narrow */
@container specimen (max-width: 360px) {
  .stage-title {
    font-size: 10px;
  }

  .chip-row {
    padding: var(--space-md);
  }
}