:root {
  --bg: #F6F3EC;
  --bg-cell: #F1ECE2;
  --ink: #1A1815;
  --ink-soft: #5A5247;
  --ink-hush: #8A8275;
  --accent: #8C6A2B;
  --rule: rgba(26, 24, 21, 0.14);
  --grid-rule: rgba(26, 24, 21, 0.08);
  --serif: 'Source Serif 4', 'Source Serif Pro', 'Iowan Old Style', Georgia, serif;
  --mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
}

[data-theme="dark"] {
  --bg: #090C13;
  --bg-cell: #11151F;
  --ink: #E5E7EA;
  --ink-soft: #948CA6;
  --ink-hush: #6B6577;
  --accent: #C29F5E;
  --rule: rgba(229, 231, 234, 0.12);
  --grid-rule: rgba(229, 231, 234, 0.07);
}

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

html {
  background: var(--bg);
  color: var(--ink);
}

body {
  margin: 0 auto;
  max-width: 46rem;
  padding: 2rem 1.5rem 4rem;
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.58;
  font-feature-settings: "kern", "liga", "onum";
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  transition: background-color 240ms ease, color 240ms ease;
  background: var(--bg);
  color: var(--ink);
}

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 160ms ease;
}

a:hover { color: var(--accent); }

em { font-style: italic; }

strong {
  font-weight: 600;
  color: var(--ink);
}

::selection {
  background: var(--accent);
  color: var(--bg);
}

/* Header --------------------------------------------------------- */

.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding-bottom: 1.2rem;
  margin-bottom: 3rem;
  border-bottom: 1px solid var(--grid-rule);
}

.mark {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: var(--ink);
}

.sigil {
  width: 28px;
  height: 28px;
  color: var(--accent);
  display: block;
  flex-shrink: 0;
}

.sigil path {
  fill: none;
  stroke: currentColor;
  stroke-width: 6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.wordmark {
  font-family: var(--serif);
  font-weight: 600;
  letter-spacing: 0.18em;
  font-size: 0.9rem;
  text-transform: uppercase;
}

.page-nav {
  display: flex;
  gap: 1.4rem;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.page-nav a {
  text-decoration: none;
  color: var(--ink-soft);
  position: relative;
}

.page-nav a::before {
  content: "→ ";
  color: var(--accent);
  opacity: 0.7;
}

.page-nav a:hover { color: var(--accent); }

/* Hero ----------------------------------------------------------- */

.hero {
  margin: 2.5rem 0 4rem;
  position: relative;
}

.meta-line {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-hush);
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-bottom: 1.8rem;
}

.meta-line .dot {
  color: var(--accent);
}

.hero h1 {
  font-family: var(--serif);
  font-weight: 400;
  font-style: italic;
  font-size: clamp(2.1rem, 5vw, 3.2rem);
  line-height: 1.08;
  letter-spacing: -0.014em;
  margin: 0 0 1.4rem;
}

.lede {
  font-size: 1.05rem;
  line-height: 1.6;
  color: var(--ink-soft);
  margin: 0;
  max-width: 36rem;
}

.alpha-wave {
  display: block;
  width: 100%;
  height: 40px;
  margin-top: 2.2rem;
  color: var(--accent);
  opacity: 0.55;
}

.alpha-wave path {
  fill: none;
  stroke: currentColor;
  stroke-width: 1.2;
  stroke-linecap: round;
  stroke-dasharray: 2400;
  stroke-dashoffset: 2400;
  animation: hs-wave 2200ms cubic-bezier(0.65, 0, 0.35, 1) 200ms forwards;
}

@keyframes hs-wave {
  to { stroke-dashoffset: 0; }
}

/* Sections / blocks --------------------------------------------- */

main section {
  margin: 3.2rem 0;
}

main section h2 {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
  margin: 0 0 1.6rem;
  padding-bottom: 0.7rem;
  border-bottom: 1px solid var(--grid-rule);
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
}

main section h2 .tag {
  color: var(--accent);
  font-weight: 400;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
}

main section h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.02rem;
  margin: 0 0 0.45rem;
  color: var(--ink);
}

main p {
  margin: 0 0 1.05rem;
}

.blocks.compact {
  margin: 2rem 0;
}

.blocks.compact p {
  margin: 0;
}

/* 2-col card grid ----------------------------------------------- */

.grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--grid-rule);
  border: 1px solid var(--grid-rule);
  margin-bottom: 1.4rem;
}

.cell {
  background: var(--bg);
  padding: 1.15rem 1.25rem 1.2rem;
}

.cell p {
  margin: 0;
  font-size: 0.96rem;
  color: var(--ink-soft);
  line-height: 1.5;
}

/* Spec list ----------------------------------------------------- */

.spec {
  margin: 0 0 1rem;
  padding: 0;
  border-top: 1px solid var(--grid-rule);
}

.spec > div {
  display: grid;
  grid-template-columns: 9rem 1fr;
  gap: 1rem;
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--grid-rule);
}

.spec dt {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-hush);
  padding-top: 0.18rem;
}

.spec dd {
  margin: 0;
  color: var(--ink);
  font-size: 0.98rem;
}

/* Ladder list (applications) ------------------------------------ */

.ladder {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--grid-rule);
}

.ladder li {
  display: grid;
  grid-template-columns: 9rem 1fr;
  gap: 1rem;
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--grid-rule);
  align-items: baseline;
}

.ladder .rung {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
}

.ladder li > span:last-child {
  color: var(--ink-soft);
  font-size: 0.98rem;
}

/* Misc ---------------------------------------------------------- */

.quiet {
  color: var(--ink-hush);
  font-size: 0.84rem;
  font-family: var(--mono);
  letter-spacing: 0.02em;
}

.section-link {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.section-link a {
  text-decoration: none;
  color: var(--ink-soft);
}

.section-link a:hover { color: var(--accent); }

hr.rule {
  border: none;
  border-top: 1px solid var(--rule);
  margin: 3rem auto;
  width: 100%;
}

/* Bibliography (research page) ---------------------------------- */

.bibliography {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.5;
}

.bibliography li {
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--grid-rule);
  color: var(--ink-soft);
}

.bibliography li:last-child { border-bottom: none; }

.bibliography li strong {
  color: var(--ink);
  font-weight: 600;
}

.bibliography li em {
  color: var(--ink);
}

/* Footer -------------------------------------------------------- */

.page-footer {
  margin-top: 5rem;
  padding-top: 1.6rem;
  border-top: 1px solid var(--rule);
  font-family: var(--mono);
  font-size: 0.74rem;
  line-height: 1.5;
  letter-spacing: 0.04em;
  color: var(--ink-soft);
}

.colophon {
  width: 18px;
  height: 18px;
  color: var(--accent);
  display: block;
  margin-bottom: 0.9rem;
}

.colophon path {
  fill: none;
  stroke: currentColor;
  stroke-width: 7;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.foot-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.4rem;
  text-transform: uppercase;
  margin-bottom: 0.6rem;
}

.page-footer p {
  margin: 0.35rem 0;
  text-transform: none;
  letter-spacing: 0;
}

.theme-toggle {
  margin-top: 1.5rem;
  background: transparent;
  color: var(--ink-soft);
  border: 1px solid var(--rule);
  padding: 0.4rem 0.9rem;
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  cursor: pointer;
  transition: color 160ms ease, border-color 160ms ease, background-color 160ms ease;
}

.theme-toggle::before {
  content: "[ ";
  color: var(--accent);
}

.theme-toggle::after {
  content: " ]";
  color: var(--accent);
}

.theme-toggle:hover {
  color: var(--accent);
  border-color: var(--accent);
}

.theme-toggle:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 3px;
}

/* Mark draw-in animation ---------------------------------------- */

.sigil path {
  stroke-dasharray: 220;
  stroke-dashoffset: 220;
  animation: hs-draw 720ms cubic-bezier(0.65, 0, 0.35, 1) forwards;
}

.sigil .hs-hemi-left  { animation-delay:  60ms; }
.sigil .hs-hemi-right { animation-delay: 320ms; }
.sigil .hs-alpha      { animation-delay: 580ms; }

@keyframes hs-draw {
  to { stroke-dashoffset: 0; }
}

.colophon path {
  stroke-dasharray: none;
  stroke-dashoffset: 0;
  animation: none;
}

@media (prefers-reduced-motion: reduce) {
  .sigil path,
  .alpha-wave path {
    stroke-dasharray: none;
    stroke-dashoffset: 0;
    animation: none;
  }
  body { transition: none; }
}

/* Narrow viewports --------------------------------------------- */

@media (max-width: 38rem) {
  body { padding: 1.5rem 1.1rem 3rem; font-size: 16px; }
  .page-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
  .hero { margin: 1.5rem 0 3rem; }
  .grid { grid-template-columns: 1fr; }
  .spec > div,
  .ladder li {
    grid-template-columns: 1fr;
    gap: 0.2rem;
  }
}