:root {
  --canvas-bg: #000000;
  --canvas-text: #ffffff;
  --panel-bg: #000000;
  --panel-border: #333333;
  --panel-control-bg: #111111;
  --panel-control-bg-hover: #222222;
  --text-primary: #ffffff;
  --text-muted: rgba(255, 255, 255, 0.7);
  --text-faint: rgba(255, 255, 255, 0.5);
  --grid-line: rgba(255, 255, 255, 0.12);
  --trace-line: #ffffff;
  --disc-line: rgba(255, 255, 255, 0.22);
  --accent: #ff5f39;
  --unit: 4px;
  --section-spacing: 8rem;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  --fs-hero: clamp(3.8rem, 7.2vw, 8.6rem);
  --fs-h2: clamp(2rem, 4vw, 4.8rem);
  --fs-h3: 1.2rem;
  --fs-body: 1rem;
  --fs-small: 0.8125rem;
  --fw-thin: 100;
  --fw-extra-light: 200;
  --fw-light: 300;
  --fw-normal: 400;
  --fw-bold: 500;
  --ls-tight: -0.035em;
  --ls-normal: 0em;
  --ls-wide: 0.08em;
  --radius-none: 0;
  --radius-sm: 4px;
  --radius-full: 9999px;
  --shadow-glow: 0 0 20px rgba(255, 255, 255, 0.1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--canvas-bg); }
body {
  margin: 0;
  background: var(--canvas-bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  font-weight: var(--fw-light);
  line-height: 1.6;
}
a { color: inherit; }
button, select, input { font: inherit; }
button:focus-visible, select:focus-visible, input:focus-visible, a:focus-visible {
  outline: 1px solid var(--text-primary);
  outline-offset: 3px;
}
img, video { display: block; max-width: 100%; height: auto; object-fit: contain; }

nav {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 100;
  padding: 1.25rem 6.5rem 1.25rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  mix-blend-mode: difference;
  font: var(--fs-small)/1.2 var(--font-mono);
  letter-spacing: var(--ls-wide);
}
nav a { text-decoration: none; opacity: 0.68; transition: opacity 0.25s ease; }
nav a:hover { opacity: 1; }
.nav-links { display: flex; gap: 1.5rem; }

.hero {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 9rem max(2rem, 6vw) 5rem;
  border-bottom: 1px solid var(--grid-line);
}
.eyebrow, .section-index, .panel-index, .meta, .technical-note, .technical-link,
.status-badge, figcaption, dt, .canvas-readout, .speed-control, footer {
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: var(--ls-wide);
  text-transform: uppercase;
}
.eyebrow, .section-index, .panel-index, .meta { color: var(--text-faint); }
h1 {
  margin: 1.5rem 0 2rem;
  max-width: 30ch;
  font-size: clamp(3.6rem, 5.4vw, 6.8rem);
  font-weight: var(--fw-thin);
  letter-spacing: var(--ls-tight);
  line-height: 0.92;
  text-wrap: balance;
}
.hero-credit {
  margin: -0.5rem 0 2rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: clamp(0.9rem, 1.35vw, 1.2rem);
  letter-spacing: var(--ls-wide);
  text-transform: none;
}
.hero-subtitle {
  max-width: 48rem;
  margin: 0 0 1rem;
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: clamp(0.85rem, 1.2vw, 1.1rem);
  letter-spacing: var(--ls-wide);
  text-transform: uppercase;
}
.hero-copy {
  max-width: 48rem;
  margin: 0;
  color: var(--text-muted);
  font-size: clamp(1.15rem, 2vw, 1.75rem);
  line-height: 1.55;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 2rem; }
.whitepaper-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3rem;
  padding: 0.8rem 1rem;
  border: 1px solid var(--text-primary);
  color: var(--canvas-bg);
  background: var(--text-primary);
  font-family: var(--font-mono);
  font-size: var(--fs-small);
  letter-spacing: var(--ls-wide);
  line-height: 1.4;
  text-decoration: none;
  text-transform: uppercase;
  transition: color 0.2s ease, background 0.2s ease;
}
.whitepaper-button:hover { color: var(--text-primary); background: transparent; }
.hero-status { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 3rem; }
.hero-status span, .status-badge {
  border: 1px solid var(--panel-border);
  padding: 0.45rem 0.7rem;
  color: var(--text-muted);
  background: var(--panel-bg);
}
.boundary-line {
  max-width: 50rem;
  margin: 3rem 0 0;
  padding-top: 1.5rem;
  border-top: 1px solid var(--grid-line);
  color: var(--text-faint);
  font-size: var(--fs-small);
}

section { max-width: 1600px; margin: 0 auto; padding: var(--section-spacing) 2rem; }
.section-head { display: grid; grid-template-columns: minmax(140px, 0.35fr) 1fr; column-gap: 2rem; align-items: start; }
.section-head h2 {
  grid-column: 2;
  margin: 0;
  font-size: var(--fs-h2);
  font-weight: var(--fw-light);
  letter-spacing: var(--ls-tight);
  line-height: 1.05;
  text-transform: none;
}
.section-head > p:last-child { grid-column: 2; max-width: 52rem; color: var(--text-muted); font-size: 1.2rem; }
.section-index { grid-column: 1; grid-row: 1 / span 2; margin: 0.7rem 0 0; }

.formula-picker {
  margin: 5rem 0 2rem;
  display: grid;
  grid-template-columns: minmax(140px, 0.35fr) minmax(280px, 1fr) minmax(240px, auto);
  align-items: center;
  gap: 2rem;
  padding: 1.25rem 0;
  border-top: 1px solid var(--panel-border);
  border-bottom: 1px solid var(--panel-border);
}
.formula-picker label { font-family: var(--font-mono); font-size: var(--fs-small); letter-spacing: var(--ls-wide); }
select {
  width: 100%;
  padding: 0.9rem 2.5rem 0.9rem 1rem;
  color: var(--text-primary);
  background: var(--panel-control-bg);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-none);
}
.formula-meta { display: flex; flex-wrap: wrap; gap: 0.45rem; justify-content: flex-end; }

.equation-card {
  display: grid;
  grid-template-columns: minmax(280px, 0.7fr) minmax(0, 1.3fr);
  gap: 2rem;
  padding: 2rem;
  border: 1px solid var(--panel-border);
  margin-bottom: 2rem;
}
.equation-card h3, .process-panel h3, .card h3 { margin: 0.3rem 0 0; font-size: var(--fs-h3); font-weight: var(--fw-normal); }
.equation-render {
  min-width: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.5rem;
  overflow-x: auto;
}
#formula-equation { min-height: 4.8rem; font-size: clamp(0.78rem, 1.2vw, 1.18rem); }
#formula-domain { color: var(--text-muted); }
.muted, .panel-copy { color: var(--text-muted); }
.technical-note { color: var(--text-faint); margin: 0; }

.process-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; }
.process-panel { min-width: 0; padding: 1.25rem; border: 1px solid var(--panel-border); background: var(--panel-bg); }
.panel-head { min-height: 5.4rem; display: flex; justify-content: space-between; gap: 1rem; align-items: flex-start; }
.panel-head .status-badge { flex: 0 0 auto; }
.notebook-frame, .video-frame { margin: 1.5rem 0 1rem; }
.notebook-frame img {
  width: 100%;
  max-height: 58rem;
  margin: auto;
  object-fit: contain;
  background: var(--panel-control-bg);
}
figcaption { color: var(--text-faint); margin-top: 0.75rem; line-height: 1.5; }
.technical-link { display: inline-block; margin-top: 1rem; color: var(--text-muted); text-decoration: none; border-bottom: 1px solid var(--panel-border); }
.technical-link:hover { color: var(--text-primary); border-color: var(--text-primary); }

.canvas-frame { position: relative; margin: 1.5rem 0 1rem; border: 1px solid var(--panel-border); background: var(--canvas-bg); }
#trajectory-canvas { display: block; width: 100%; aspect-ratio: 1; }
.canvas-readout {
  position: absolute;
  inset: auto 0 0;
  display: flex;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.65rem;
  color: var(--text-muted);
  background: linear-gradient(to top, var(--canvas-bg), transparent);
}
.trajectory-controls { display: grid; grid-template-columns: repeat(3, auto); gap: 0.5rem; align-items: center; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 0.85rem;
  min-height: 2.8rem;
  color: var(--text-primary);
  background: var(--panel-control-bg);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background 0.2s ease, border-color 0.2s ease;
}
.btn:hover { background: var(--panel-control-bg-hover); border-color: var(--text-primary); }
.btn-secondary { color: var(--text-muted); }
.speed-control { grid-column: 1 / -1; display: flex; justify-content: space-between; margin-top: 0.8rem; color: var(--text-muted); }
#trajectory-speed { grid-column: 1 / -1; width: 100%; accent-color: var(--text-primary); }
.metric-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; margin: 1.5rem 0 0; }
.metric-grid div { padding-top: 0.8rem; border-top: 1px solid var(--grid-line); }
.metric-grid dt { color: var(--text-faint); }
.metric-grid dd { margin: 0.3rem 0 0; font-family: var(--font-mono); font-size: var(--fs-small); }
.video-frame video { width: 100%; background: var(--canvas-bg); border: 1px solid var(--panel-border); }

.method-section, .concept-section, .whitepaper-section, .boundary-section { border-top: 1px solid var(--grid-line); }
.method-flow { margin-top: 5rem; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 1px solid var(--panel-border); border-left: 1px solid var(--panel-border); }
.method-flow > div { min-height: 14rem; padding: 1.5rem; border-right: 1px solid var(--panel-border); border-bottom: 1px solid var(--panel-border); }
.method-flow span { display: block; color: var(--text-faint); font-family: var(--font-mono); margin-bottom: 4rem; }
.method-flow strong { display: block; font-weight: var(--fw-normal); }
.method-flow p { color: var(--text-muted); }
.whitepaper-action {
  margin-top: 4rem;
  padding: 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  border: 1px solid var(--panel-border);
}
.whitepaper-button-large { min-height: 4rem; padding-inline: 1.5rem; }
.whitepaper-action .technical-note { max-width: 34rem; text-align: right; line-height: 1.7; }
.boundary-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; margin-top: 5rem; }
.card { border: 1px solid var(--panel-border); padding: 2rem; background: transparent; transition: background 0.3s ease, border-color 0.3s ease; }
.card:hover { background: var(--panel-control-bg); border-color: var(--text-primary); }
.card p:last-child { color: var(--text-muted); }

footer { display: flex; justify-content: space-between; gap: 2rem; padding: 2rem; border-top: 1px solid var(--grid-line); color: var(--text-faint); }
footer p { max-width: 44rem; margin: 0; }
.fade-in { opacity: 0; transform: translateY(18px); transition: opacity 0.8s ease, transform 0.8s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

@media (max-width: 1120px) {
  .process-grid { grid-template-columns: 1fr; }
  .process-panel { display: grid; grid-template-columns: minmax(240px, 0.7fr) minmax(0, 1.3fr); column-gap: 2rem; }
  .process-panel .panel-head, .process-panel .panel-copy, .process-panel .technical-link, .process-panel .metric-grid, .process-panel .trajectory-controls { grid-column: 1; }
  .process-panel figure, .process-panel .canvas-frame { grid-column: 2; grid-row: 1 / span 6; }
  .method-flow { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 768px) {
  :root { --section-spacing: 5rem; --fs-hero: clamp(3rem, 13vw, 5rem); }
  nav { padding: 1rem 4.5rem 1rem 1rem; }
  .nav-links { display: none; }
  .hero { padding-inline: 1rem; }
  h1 { max-width: none; font-size: clamp(2.35rem, 10vw, 3.25rem); line-height: 0.98; }
  section { padding-inline: 1rem; }
  .section-head, .formula-picker, .equation-card { display: block; }
  .section-index { margin-bottom: 1rem; }
  .formula-picker > * { margin-bottom: 0.8rem; }
  .formula-meta { justify-content: flex-start; }
  .equation-copy { margin-bottom: 2rem; }
  .process-panel { display: block; }
  .process-panel figure, .process-panel .canvas-frame { grid-column: auto; grid-row: auto; }
  .trajectory-controls { grid-template-columns: 1fr; }
  .speed-control, #trajectory-speed { grid-column: 1; }
  .method-flow, .boundary-grid { grid-template-columns: 1fr; }
  .whitepaper-action { align-items: stretch; flex-direction: column; padding: 1rem; }
  .whitepaper-button-large { width: 100%; }
  .whitepaper-action .technical-note { text-align: left; }
  .method-flow > div { min-height: 10rem; }
  .method-flow span { margin-bottom: 2rem; }
  footer { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}