:root {
  --ink: #e8e7e1;
  --muted: #999b91;
  --accent: #ff5a24;
  --accent-secondary: #8ccfe3;
  --background: #08090d;
  --line: rgba(232, 231, 225, 0.16);
  --on-accent: #10110f;
  --page-padding: clamp(1.25rem, 4vw, 4.5rem);
}

html[data-theme="light"] {
  --ink: #191a17;
  --muted: #5d6158;
  --accent: #d94a1d;
  --accent-secondary: #176f87;
  --background: #f5f1e9;
  --line: rgba(25, 26, 23, 0.18);
  --on-accent: #fffdf7;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  min-width: 20rem;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 88% 8%, color-mix(in srgb, var(--accent) 12%, transparent), transparent 30rem),
    radial-gradient(circle at 7% 65%, color-mix(in srgb, var(--accent-secondary) 7%, transparent), transparent 34rem),
    var(--background);
  font-family: "Space Grotesk", sans-serif;
  transition: color 350ms ease, background-color 350ms ease;
}

a { color: inherit; text-decoration: none; }
button { font: inherit; }

.skip-link {
  position: fixed;
  z-index: 20;
  top: 0.75rem;
  left: 1rem;
  padding: 0.75rem 1rem;
  background: var(--accent);
  color: var(--on-accent);
  font: 500 0.7rem/1 "DM Mono", monospace;
  text-transform: uppercase;
  transform: translateY(-150%);
}

.skip-link:focus { transform: translateY(0); }

.site-header {
  position: sticky;
  z-index: 10;
  top: 0;
  display: flex;
  min-height: 4.5rem;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0 var(--page-padding);
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--background) 86%, transparent);
  backdrop-filter: blur(16px) saturate(120%);
}

.wordmark { display: inline-flex; width: 3.25rem; height: 2.65rem; align-items: center; justify-content: center; }
.wordmark img { display: block; width: 100%; height: auto; }
html[data-theme="light"] .wordmark img { filter: invert(1) brightness(0.98); mix-blend-mode: darken; }
.site-header__actions { display: flex; align-items: center; gap: clamp(0.8rem, 2vw, 1.5rem); }

.back-link,
.theme-toggle {
  color: var(--muted);
  font: 500 0.65rem/1 "DM Mono", monospace;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.back-link span { color: var(--accent-secondary); }
.back-link:hover { color: var(--ink); }

.theme-toggle {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
}

.theme-toggle > span:first-child {
  display: block;
  width: 1rem;
  height: 1rem;
  border: 1px solid var(--muted);
  border-radius: 50%;
  background: linear-gradient(90deg, var(--ink) 50%, transparent 50%);
}

.back-link:focus-visible,
.theme-toggle:focus-visible,
.page-footer a:focus-visible {
  border-radius: 2px;
  outline: 2px solid var(--accent-secondary);
  outline-offset: 0.35rem;
}

main { padding: 0 var(--page-padding) clamp(3rem, 7vw, 6rem); }

.page-intro {
  display: grid;
  max-width: 96rem;
  margin: 0 auto;
  padding: clamp(4.5rem, 9vw, 8rem) 0 clamp(2.5rem, 5vw, 4.5rem);
  grid-template-columns: minmax(0, 1.4fr) minmax(18rem, 0.6fr);
  gap: 1.5rem 4rem;
}

.eyebrow {
  grid-column: 1 / -1;
  margin: 0;
  color: var(--accent-secondary);
  font: 500 0.68rem/1 "DM Mono", monospace;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1 {
  max-width: 11ch;
  margin: 0;
  font: 500 clamp(3.5rem, 7vw, 7.5rem)/0.84 "Cormorant Garamond", serif;
  letter-spacing: -0.055em;
}

h1 span { color: var(--accent); }

.page-intro > p:last-child {
  align-self: end;
  margin: 0;
  color: var(--muted);
  font-size: clamp(0.95rem, 1.3vw, 1.08rem);
  line-height: 1.75;
}

.concept-gallery { max-width: 96rem; margin: 0 auto; }

.concept-group + .concept-group {
  margin-top: clamp(4.5rem, 10vw, 9rem);
  padding-top: clamp(3rem, 7vw, 6rem);
  border-top: 1px solid var(--line);
}

.concept-group__heading {
  display: grid;
  max-width: 79rem;
  align-items: end;
  margin: 0 auto clamp(2rem, 4vw, 3.5rem);
  grid-template-columns: minmax(0, 1.3fr) minmax(18rem, 0.7fr);
  gap: 1.5rem 4rem;
}

.concept-group .eyebrow { margin-bottom: 1rem; }

.concept-group h2 {
  margin: 0;
  font: 500 clamp(2.7rem, 5vw, 5.25rem)/0.9 "Cormorant Garamond", serif;
  letter-spacing: -0.045em;
}

.concept-group__heading > p {
  margin: 0;
  color: var(--muted);
  line-height: 1.7;
}

.concept-group__heading strong { color: var(--accent); font-weight: 600; }
.concept-sheet { max-width: 79rem; margin: 0 auto; }

.concept-sheet__image {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background: #10110f;
  box-shadow: 0 2rem 6rem rgba(0, 0, 0, 0.26);
}

.concept-sheet img { display: block; width: 100%; height: auto; }

.concept-sheet__numbers {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(3, 1fr);
  pointer-events: none;
}

.concept-sheet__numbers span {
  align-self: start;
  justify-self: start;
  min-width: 2.25rem;
  margin: clamp(0.45rem, 1vw, 0.9rem);
  padding: 0.45rem 0.5rem;
  border: 1px solid rgba(140, 207, 227, 0.42);
  background: rgba(8, 9, 13, 0.84);
  color: #8ccfe3;
  font: 500 clamp(0.5rem, 0.8vw, 0.68rem)/1 "DM Mono", monospace;
  letter-spacing: 0.08em;
  text-align: center;
  backdrop-filter: blur(8px);
}

.concept-sheet__numbers .is-active {
  border-color: rgba(255, 90, 36, 0.72);
  background: rgba(255, 90, 36, 0.92);
  color: #10110f;
}

figcaption {
  margin-top: 1rem;
  color: var(--muted);
  font: 400 0.62rem/1.6 "DM Mono", monospace;
  letter-spacing: 0.06em;
  text-align: center;
  text-transform: uppercase;
}

.page-footer {
  display: flex;
  max-width: 96rem;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  margin: clamp(3rem, 7vw, 6rem) auto 0;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font: 500 0.62rem/1.5 "DM Mono", monospace;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.page-footer p { margin: 0; }
.page-footer a { color: var(--ink); }
.page-footer a span { color: var(--accent); }

@media (max-width: 760px) {
  .page-intro { grid-template-columns: 1fr; }
  .page-intro > p:last-child { max-width: 40rem; }
  .concept-group__heading { grid-template-columns: 1fr; }
  .concept-group__heading > p { max-width: 40rem; }
}

@media (max-width: 520px) {
  .site-header { min-height: 4rem; }
  .theme-toggle__label { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }
  .page-intro { padding-top: 4rem; }
  h1 { font-size: clamp(3.25rem, 17vw, 5rem); }
  .concept-sheet__numbers span { min-width: 1.8rem; padding: 0.35rem 0.3rem; }
  .page-footer { align-items: flex-start; flex-direction: column; }
}

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