:root {
  color-scheme: dark;
  --ink: #f2f5f7;
  --muted: #9ca8b8;
  --quiet: #6f7c8c;
  --line: rgba(255, 255, 255, 0.12);
  --panel: rgba(18, 25, 36, 0.82);
  --cyan: #70d6d1;
  --amber: #f1bf6b;
  --max: 76rem;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #090d14;
  color: var(--ink);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 0;
  overflow-x: hidden;
  background:
    radial-gradient(circle at 12% 4%, rgba(44, 109, 118, 0.24), transparent 30rem),
    radial-gradient(circle at 92% 22%, rgba(115, 77, 29, 0.17), transparent 28rem),
    #090d14;
  color: var(--ink);
}

a {
  color: inherit;
}

.site-header,
main,
footer {
  width: min(calc(100% - 2rem), var(--max));
  margin-inline: auto;
}

.site-header {
  min-height: 5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  border-bottom: 1px solid var(--line);
}

.wordmark,
.repo-link {
  text-decoration: none;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-weight: 720;
  letter-spacing: -0.02em;
}

.wordmark-mark {
  width: 1.5rem;
  height: 0.18rem;
  display: inline-block;
  background: var(--cyan);
  transform: rotate(-28deg);
  border-radius: 999px;
  box-shadow: 0 0 1rem rgba(112, 214, 209, 0.45);
}

.repo-link {
  color: var(--muted);
  font-size: 0.9rem;
}

.repo-link:hover,
.repo-link:focus-visible {
  color: var(--ink);
}

.hero {
  min-height: 40rem;
  display: grid;
  align-content: center;
  max-width: 61rem;
  padding: 7rem 0 5rem;
}

.eyebrow,
.section-number,
.card-kicker {
  margin: 0;
  color: var(--cyan);
  font-size: 0.72rem;
  font-weight: 760;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  max-width: 14ch;
  margin: 1rem 0 1.4rem;
  font-size: clamp(3.1rem, 9vw, 7.6rem);
  line-height: 0.92;
  letter-spacing: -0.07em;
}

.hero-copy {
  max-width: 43rem;
  margin: 0;
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.35rem);
  line-height: 1.65;
}

.hero-proof {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin-top: 3.5rem;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 1rem;
  background: var(--line);
}

.hero-proof div {
  min-width: 0;
  padding: 1.2rem 1.4rem;
  background: rgba(9, 13, 20, 0.92);
}

.hero-proof strong,
.hero-proof span {
  display: block;
}

.hero-proof strong {
  color: var(--amber);
  font-size: 1.75rem;
  font-weight: 650;
}

.hero-proof span {
  margin-top: 0.25rem;
  color: var(--quiet);
  font-size: 0.8rem;
  line-height: 1.35;
}

.gallery-section {
  padding: 7rem 0;
  border-top: 1px solid var(--line);
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(16rem, 0.85fr);
  gap: 3rem;
  align-items: end;
  margin-bottom: 2.5rem;
}

.section-heading h2,
.closing h2 {
  margin: 0.75rem 0 0;
  font-size: clamp(2.2rem, 5vw, 4.7rem);
  line-height: 1;
  letter-spacing: -0.055em;
}

.section-heading > p {
  margin: 0;
  color: var(--muted);
  line-height: 1.65;
}

.gallery-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.figure-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.25rem;
}

.figure-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 1rem;
  background: var(--panel);
  box-shadow: 0 1.2rem 4rem rgba(0, 0, 0, 0.22);
}

.figure-wide {
  grid-column: span 2;
}

.figure-stage {
  display: grid;
  place-items: center;
  min-height: 15rem;
  padding: 1.25rem;
  background: #f5f7fa;
}

.figure-stage img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: 15rem;
  object-fit: contain;
}

.gallery-grid-three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.scene-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 1rem;
  background: var(--panel);
  box-shadow: 0 1.2rem 4rem rgba(0, 0, 0, 0.22);
}

.scene-card video {
  display: block;
  width: 100%;
  max-width: 100%;
  aspect-ratio: 16 / 9;
  border: 0;
  background: #000;
  object-fit: contain;
}

.card-copy {
  padding: 1.4rem 1.5rem 1.6rem;
}

.card-copy h3 {
  margin: 0.65rem 0 1rem;
  font-size: clamp(1.25rem, 2vw, 1.7rem);
  line-height: 1.1;
  letter-spacing: -0.035em;
}

.prompt,
.spec,
.claim {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.65;
}

.spec span {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--cyan);
  font-size: 0.68rem;
  font-weight: 760;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.prompt {
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

.prompt > span {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--cyan);
  font-size: 0.68rem;
  font-weight: 760;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.source-input {
  margin-top: 0.9rem;
  color: var(--quiet);
  font-size: 0.78rem;
}

.source-input summary {
  width: fit-content;
  cursor: pointer;
}

.source-input p {
  margin: 0.65rem 0 0;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.55;
}

.claim span {
  display: block;
  margin-bottom: 0.35rem;
  color: var(--amber);
  font-size: 0.68rem;
  font-weight: 760;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

code {
  padding: 0.08em 0.3em;
  border-radius: 0.3em;
  background: rgba(255, 255, 255, 0.08);
  font-size: 0.9em;
}

.hand-section .section-number,
.hand-section .card-kicker {
  color: var(--amber);
}

.closing {
  display: grid;
  justify-items: start;
  padding: 8rem 0;
  border-top: 1px solid var(--line);
}

.closing h2 {
  max-width: 17ch;
}

.button {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  margin-top: 2.2rem;
  padding: 0.9rem 1.15rem;
  border-radius: 0.6rem;
  background: var(--ink);
  color: #090d14;
  font-weight: 720;
  text-decoration: none;
}

.button:hover,
.button:focus-visible {
  background: var(--cyan);
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 2rem 0 3rem;
  border-top: 1px solid var(--line);
  color: var(--quiet);
  font-size: 0.82rem;
}

footer p {
  margin: 0;
}

@media (max-width: 56rem) {
  .figure-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .gallery-grid-three {
    grid-template-columns: 1fr;
  }

  .gallery-grid-three .scene-card {
    display: grid;
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  }

  .gallery-grid-three .scene-card video {
    height: 100%;
  }
}

@media (max-width: 42rem) {
  .site-header,
  main,
  footer {
    width: min(calc(100% - 1.25rem), var(--max));
  }

  .hero {
    min-height: auto;
    padding: 5.5rem 0 4rem;
  }

  h1 {
    font-size: clamp(3.4rem, 18vw, 5.2rem);
  }

  .hero-proof,
  .section-heading,
  .gallery-grid,
  .figure-grid,
  .gallery-grid-three .scene-card {
    grid-template-columns: 1fr;
  }

  .figure-wide {
    grid-column: auto;
  }

  .hero-proof {
    overflow: visible;
    gap: 0;
    background: transparent;
  }

  .hero-proof div + div {
    border-top: 1px solid var(--line);
  }

  .section-heading {
    gap: 1.4rem;
  }

  .gallery-section {
    padding: 5rem 0;
  }

  .gallery-grid-three .scene-card video {
    height: auto;
  }

  .closing {
    padding: 6rem 0;
  }

  footer {
    flex-direction: column;
  }
}

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

/* Two links in the header now: the series and the repo. */
.header-links {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

/* Prose sections — the definition, the "why geometry" grid, and the FAQ. These
   carry the page's semantic weight for search and answer engines, so they are
   real text at a readable measure rather than another card grid. Headings step
   down from the hero's scale instead of competing with the gallery's display
   type. */
.hero-tagline {
  max-width: 43rem;
  margin: 1rem 0 1.4rem;
  color: var(--cyan);
  font-size: clamp(1.05rem, 2.2vw, 1.5rem);
  letter-spacing: -0.02em;
}

.prose-section {
  padding: 4.5rem 0 0;
  border-top: 1px solid var(--line);
  margin-top: 4.5rem;
}

.prose-section h2 {
  margin: 0 0 1.6rem;
  font-size: clamp(1.7rem, 3.4vw, 2.7rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.prose-section p {
  max-width: 44rem;
  margin: 0 0 1.15rem;
  color: var(--muted);
  font-size: 1.02rem;
  line-height: 1.72;
}

.prose-section p strong {
  color: var(--ink);
  font-weight: 600;
}

.prose-section .lede {
  color: var(--ink);
  font-size: clamp(1.08rem, 1.9vw, 1.28rem);
  line-height: 1.6;
}

.why-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 1.5rem 2.2rem;
  margin-top: 0.5rem;
}

.why-item h3 {
  margin: 0 0 0.5rem;
  font-size: 1.02rem;
  letter-spacing: -0.01em;
}

.why-item h3::before {
  content: "";
  display: block;
  width: 1.6rem;
  height: 2px;
  margin-bottom: 0.85rem;
  background: var(--cyan);
}

.why-item p {
  margin: 0;
  font-size: 0.95rem;
  line-height: 1.62;
}

.faq-item {
  padding: 1.5rem 0;
  border-top: 1px solid var(--line);
  max-width: 48rem;
}

.faq-item:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.faq-item h3 {
  margin: 0 0 0.6rem;
  font-size: 1.06rem;
  line-height: 1.35;
  letter-spacing: -0.015em;
}

.faq-item p {
  margin: 0;
}

.faq-item em {
  color: var(--ink);
  font-style: italic;
}

/* Install block. The site had no install instruction at all before the package
   was on PyPI, which made the gallery a dead end for anyone who wanted to use
   it. */
.install {
  max-width: 44rem;
  margin: 2rem 0 0;
  padding: 1.4rem 1.5rem;
  border: 1px solid var(--line);
  border-radius: 0.6rem;
  background: var(--panel);
}

.install-label {
  margin: 0 0 0.6rem !important;
  color: var(--quiet);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.install > code {
  display: block;
  font-size: 1.02rem;
  color: var(--cyan);
  overflow-x: auto;
}

.install-note {
  margin: 0.9rem 0 0 !important;
  font-size: 0.9rem !important;
  line-height: 1.6 !important;
}

.install-note code {
  color: var(--ink);
  font-size: 0.86rem;
}

.prose-section a {
  color: var(--cyan);
  text-decoration-color: rgba(112, 214, 209, 0.4);
  text-underline-offset: 0.2em;
}

/* Header navigation. The section anchors are useful on a wide screen and pure
   clutter on a phone, where the page is a short scroll anyway — so they drop
   out below the tablet breakpoint and the destination links (Writeups, PyPI,
   GitHub) stay, since those are the ones that leave the page. */
.header-links {
  flex-wrap: wrap;
  gap: 0.6rem 1.1rem;
  justify-content: flex-end;
}

.nav-secondary {
  color: var(--muted);
}

@media (max-width: 56rem) {
  .nav-secondary {
    display: none;
  }
}