:root {
  --paper: #f6f1e8;
  --paper-2: #fffdf8;
  --ink: #1d1a15;
  --ink-soft: #56503f;
  --rule: #e0d7c6;
  --accent: #14533d;
  --accent-ink: #fdf7ef;
  --shadow: 0 1px 2px rgba(29, 26, 21, .07), 0 12px 36px -12px rgba(29, 26, 21, .22);
  --serif: "EB Garamond", "Iowan Old Style", Palatino, "Palatino Linotype", Georgia, serif;
  --sans: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #14120f;
    --paper-2: #1e1b16;
    --ink: #f0e9dc;
    --ink-soft: #b3a992;
    --rule: #332e26;
    --accent: #74c4a4;
    --accent-ink: #0d1a15;
    --shadow: 0 1px 2px rgba(0, 0, 0, .5), 0 18px 44px -16px rgba(0, 0, 0, .7);
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background:
    radial-gradient(120% 80% at 50% -10%, color-mix(in srgb, var(--paper-2) 70%, transparent), transparent 60%),
    var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

.page {
  max-width: 62rem;
  margin: 0 auto;
  padding: clamp(2.5rem, 7vw, 6rem) clamp(1.25rem, 5vw, 2.5rem) 3rem;
}

/* ---------- hero ---------- */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 21rem) minmax(0, 1fr);
  gap: clamp(2rem, 6vw, 4.5rem);
  align-items: center;
}

.cover-wrap { perspective: 1400px; }

.cover {
  position: relative;
  aspect-ratio: 1 / 1.414;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 12%;
  padding: 10% 9%;
  text-align: center;
  color: #17150f;
  background:
    linear-gradient(100deg, rgba(0, 0, 0, .07) 0 1.6%, rgba(255, 255, 255, .55) 1.6% 3.2%, transparent 3.2%),
    linear-gradient(160deg, #fffefb 0%, #f4eee1 100%);
  border: 1px solid rgba(29, 26, 21, .13);
  border-radius: 2px 6px 6px 2px;
  box-shadow: var(--shadow);
  transform: rotate(-.6deg);
  transition: transform .4s ease, box-shadow .4s ease;
}

.cover:hover { transform: rotate(0deg) translateY(-4px); }

.cover-title {
  display: flex;
  flex-direction: column;
  font-family: var(--serif);
  font-size: clamp(1.1rem, 3.6vw, 1.55rem);
  font-weight: 400;
  line-height: 1.06;
  letter-spacing: .02em;
}

.cover-sub {
  margin: 0;
  font-family: var(--sans);
  font-size: clamp(.6rem, 1.7vw, .74rem);
  font-weight: 600;
  letter-spacing: .07em;
  line-height: 1.5;
  color: #3a352b;
}

/* ---------- intro ---------- */

.eyebrow {
  margin: 0 0 .9rem;
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(2.2rem, 6vw, 3.5rem);
  font-weight: 500;
  line-height: 1;
  letter-spacing: -.015em;
}

.byline {
  margin: .85rem 0 0;
  font-size: 1.02rem;
  color: var(--ink-soft);
}

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

.lede {
  margin: 1.35rem 0 0;
  max-width: 34rem;
  font-family: var(--serif);
  font-size: 1.22rem;
  line-height: 1.6;
  color: var(--ink-soft);
}

/* ---------- downloads ---------- */

.downloads {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  margin-top: 2rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  padding: .8rem 1.3rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-size: .97rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: transform .15s ease, box-shadow .2s ease, background .2s ease, border-color .2s ease;
}

.btn svg {
  width: 1.15em;
  height: 1.15em;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.btn-meta {
  font-size: .82rem;
  font-weight: 500;
  opacity: .65;
  font-variant-numeric: tabular-nums;
}

.btn-primary {
  background: var(--accent);
  color: var(--accent-ink);
  box-shadow: 0 10px 24px -12px color-mix(in srgb, var(--accent) 80%, transparent);
}

.btn-secondary {
  background: var(--paper-2);
  color: var(--ink);
  border-color: var(--rule);
}

.btn:hover { transform: translateY(-2px); }
.btn-secondary:hover { border-color: color-mix(in srgb, var(--ink) 35%, var(--rule)); }

.btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.btn.is-unavailable {
  opacity: .5;
  pointer-events: none;
  transform: none;
}

.note {
  margin: 1.1rem 0 0;
  font-size: .88rem;
  color: var(--ink-soft);
}

/* ---------- about ---------- */

.about {
  margin-top: clamp(3.5rem, 9vw, 6rem);
  padding-top: clamp(2rem, 5vw, 3rem);
  border-top: 1px solid var(--rule);
}

.about h2 {
  margin: 0 0 1rem;
  font-family: var(--serif);
  font-size: 1.6rem;
  font-weight: 500;
  letter-spacing: -.01em;
}

.about p {
  margin: 0;
  max-width: 46rem;
  font-family: var(--serif);
  font-size: 1.12rem;
  color: var(--ink-soft);
}

.facts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(8rem, 1fr));
  gap: 1.25rem;
  margin: 2.25rem 0 0;
  padding: 1.35rem 1.5rem;
  background: var(--paper-2);
  border: 1px solid var(--rule);
  border-radius: 14px;
}

.facts dt {
  font-size: .7rem;
  font-weight: 600;
  letter-spacing: .13em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

.facts dd {
  margin: .3rem 0 0;
  font-size: 1rem;
  font-weight: 500;
}

/* ---------- contents ---------- */

.toc {
  margin-top: 1.25rem;
  border: 1px solid var(--rule);
  border-radius: 14px;
  background: var(--paper-2);
}

.toc summary {
  padding: 1rem 1.5rem;
  cursor: pointer;
  font-size: .95rem;
  font-weight: 600;
  list-style: none;
  display: flex;
  align-items: center;
  gap: .55rem;
}

.toc summary::-webkit-details-marker { display: none; }

.toc summary::before {
  content: "";
  width: .5rem;
  height: .5rem;
  border-right: 2px solid var(--accent);
  border-bottom: 2px solid var(--accent);
  transform: rotate(-45deg);
  transition: transform .2s ease;
}

.toc[open] summary::before { transform: rotate(45deg); }

.toc-list {
  margin: 0;
  padding: 0 1.5rem 1.25rem;
  list-style: none;
  counter-reset: none;
}

.toc-list li {
  display: grid;
  grid-template-columns: 2rem minmax(0, 1fr) auto;
  gap: .75rem;
  align-items: baseline;
  padding: .42rem 0;
  border-top: 1px solid color-mix(in srgb, var(--rule) 55%, transparent);
}

.toc-n {
  font-size: .8rem;
  font-variant-numeric: tabular-nums;
  color: var(--ink-soft);
  text-align: right;
}

.toc-t {
  font-family: var(--serif);
  font-size: 1.05rem;
  line-height: 1.35;
}

.toc-p {
  font-size: .8rem;
  font-variant-numeric: tabular-nums;
  color: var(--ink-soft);
}

/* ---------- footer ---------- */

footer {
  margin-top: clamp(3rem, 7vw, 5rem);
  padding-top: 1.5rem;
  border-top: 1px solid var(--rule);
  font-size: .85rem;
  color: var(--ink-soft);
}

footer p { margin: 0; }

/* ---------- responsive ---------- */

@media (max-width: 780px) {
  .hero {
    grid-template-columns: 1fr;
    justify-items: center;
    text-align: center;
  }
  .cover-wrap { width: min(15rem, 62vw); }
  .lede, .byline { margin-left: auto; margin-right: auto; }
  .downloads { justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}