/* ──────────────────────────────────────────────────────────────────────────
   The Librarian — landing page
   Palette derived from the banner artwork: parchment, walnut, halo-gold.
   ────────────────────────────────────────────────────────────────────────── */

:root {
  --bg:           #F4ECDD;
  --bg-deep:      #EBE0CC;
  --surface:      #FBF5E7;
  --surface-2:   rgba(251, 245, 231, 0.78);
  --ink:          #1B1714;
  --ink-soft:     #3A3128;
  --ink-muted:    #6B5E4F;
  --rule:         #D9CDB5;
  --rule-soft:    #E5DCC8;
  --accent:       #B8893A;
  --accent-deep:  #8A6325;
  --accent-glow:  rgba(184, 137, 58, 0.18);
  --shadow:       0 1px 1px rgba(27, 23, 20, 0.05), 0 12px 30px -16px rgba(27, 23, 20, 0.25);
  --shadow-soft:  0 8px 30px -20px rgba(27, 23, 20, 0.5);
  --grain:        url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='240' height='240'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' seed='4'/><feColorMatrix values='0 0 0 0 0.42 0 0 0 0 0.31 0 0 0 0 0.18 0 0 0 0.32 0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)' opacity='0.55'/></svg>");

  --serif:  "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, "Hoefler Text", Garamond, "Times New Roman", serif;
  --sans:   system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono:   ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;

  --measure:        38rem;
  --container:      min(72rem, 92vw);
  --container-wide: min(82rem, 94vw);
  --nav-h:          3.5rem;

  --ease: cubic-bezier(0.32, 0.72, 0.18, 1);
}

[data-theme="dark"] {
  --bg:           #1A1612;
  --bg-deep:      #120F0C;
  --surface:      #231D17;
  --surface-2:   rgba(35, 29, 23, 0.78);
  --ink:          #EFE3CC;
  --ink-soft:     #D7C9AE;
  --ink-muted:    #A89478;
  --rule:         #3A2F25;
  --rule-soft:    #2C241C;
  --accent:       #D8AE5C;
  --accent-deep:  #F0C870;
  --accent-glow:  rgba(216, 174, 92, 0.22);
  --shadow:       0 1px 1px rgba(0, 0, 0, 0.35), 0 18px 40px -20px rgba(0, 0, 0, 0.7);
  --shadow-soft:  0 8px 40px -22px rgba(0, 0, 0, 0.8);
  --grain:        url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='240' height='240'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' seed='4'/><feColorMatrix values='0 0 0 0 0.85 0 0 0 0 0.7 0 0 0 0 0.42 0 0 0 0.06 0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)' opacity='0.7'/></svg>");
}

/* ─── Reset & base ─────────────────────────────────────────────────────── */

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--bg);
  background-image: var(--grain);
  background-size: 240px 240px;
  background-attachment: fixed;
  font-feature-settings: "kern", "liga", "calt";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  transition: background-color 280ms var(--ease), color 280ms var(--ease);
}

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

img { max-width: 100%; height: auto; display: block; }

a {
  color: inherit;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 160ms var(--ease), text-decoration-color 160ms var(--ease);
}
a:hover, a:focus-visible {
  color: var(--accent-deep);
  text-decoration-color: currentColor;
}
[data-theme="dark"] a:hover,
[data-theme="dark"] a:focus-visible {
  color: var(--accent-deep);
}

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

h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 500;
  color: var(--ink);
  letter-spacing: -0.005em;
  margin: 0;
}
h1 { font-size: clamp(2.75rem, 6.5vw, 4.75rem); line-height: 1.02; letter-spacing: -0.015em; }
h2 { font-size: clamp(1.85rem, 3.4vw, 2.65rem); line-height: 1.1; }
h3 { font-size: 1.18rem; line-height: 1.3; }

p { margin: 0 0 1.05em; }
code, pre { font-family: var(--mono); }

.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--ink); color: var(--bg);
  padding: 0.5rem 0.85rem;
  z-index: 100;
}
.skip:focus { left: 0.5rem; top: 0.5rem; }

/* ─── Nav ──────────────────────────────────────────────────────────────── */

.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 1.25rem;
  padding: 0.65rem clamp(1rem, 3vw, 2rem);
  min-height: var(--nav-h);
  background: var(--surface-2);
  backdrop-filter: saturate(140%) blur(10px);
  -webkit-backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--rule-soft);
  transition: background-color 220ms var(--ease), border-color 220ms var(--ease);
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 0.55rem;
  text-decoration: none;
  font-family: var(--serif);
  font-size: 1.12rem;
  letter-spacing: 0.005em;
  color: var(--ink);
}
.brand-mark {
  color: var(--accent);
  font-size: 1.35rem;
  line-height: 1;
  transform: translateY(2px);
}
.brand:hover .brand-mark { color: var(--accent-deep); }

.site-nav nav {
  display: flex;
  gap: 1.15rem;
  margin-left: auto;
  flex-wrap: wrap;
}
.site-nav nav a {
  font-size: 0.9rem;
  text-decoration: none;
  color: var(--ink-soft);
  padding: 0.25rem 0;
  position: relative;
  transition: color 160ms var(--ease);
}
.site-nav nav a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -3px;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 220ms var(--ease);
}
.site-nav nav a:hover,
.site-nav nav a:focus-visible,
.site-nav nav a[aria-current="true"] {
  color: var(--ink);
}
.site-nav nav a:hover::after,
.site-nav nav a:focus-visible::after,
.site-nav nav a[aria-current="true"]::after {
  transform: scaleX(1);
}
.site-nav nav a.external::before {
  content: "↗";
  margin-right: 0.25em;
  color: var(--accent);
  font-size: 0.85em;
}

#theme-toggle {
  appearance: none;
  background: transparent;
  border: 1px solid var(--rule);
  color: var(--ink-soft);
  width: 2.25rem;
  height: 2.25rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border-radius: 2px;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background-color 160ms var(--ease);
}
#theme-toggle:hover { color: var(--accent); border-color: var(--accent); background: var(--accent-glow); }
#theme-toggle .icon-moon { display: none; }
[data-theme="dark"] #theme-toggle .icon-sun { display: none; }
[data-theme="dark"] #theme-toggle .icon-moon { display: inline-block; }

/* ─── Hero ─────────────────────────────────────────────────────────────── */

#hero {
  position: relative;
  isolation: isolate;
  min-height: clamp(34rem, 86vh, 52rem);
  display: grid;
  align-items: start;
  justify-items: start;
  overflow: hidden;
  border-bottom: 1px solid var(--rule);
}

.hero-banner {
  position: absolute;
  inset: 0;
  z-index: -2;
}
.hero-banner img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 30%;
  transition: opacity 320ms var(--ease);
}
.hero-scrim {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(60% 55% at 8% 0%, color-mix(in srgb, var(--bg) 80%, transparent) 0%, transparent 65%);
}
[data-theme="dark"] .hero-scrim {
  background:
    radial-gradient(65% 60% at 8% 0%, color-mix(in srgb, var(--bg) 88%, transparent) 0%, transparent 65%);
}

.hero-card {
  margin: 0;
  padding: 1.25rem 1.6rem 1.4rem;
  max-width: 26rem;
  justify-self: start;
  margin-left: clamp(1rem, 3vw, 2.25rem);
  margin-top: clamp(0.25rem, 3vw, 0rem);
  text-align: left;
  background: color-mix(in srgb, var(--bg) 80%, transparent);
  backdrop-filter: blur(10px) saturate(125%);
  -webkit-backdrop-filter: blur(10px) saturate(125%);
  border: 1px solid var(--rule);
  border-radius: 2px;
  box-shadow: 0 12px 40px -20px rgba(0, 0, 0, 0.35);
  animation: rise 700ms var(--ease) both 80ms;
}
[data-theme="dark"] .hero-card {
  background: color-mix(in srgb, var(--bg) 86%, transparent);
}

.eyebrow {
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin: 0 0 1.5rem;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--rule);
}
.eyebrow span { color: var(--accent); }

.hero-card h1 {
  margin: 0;
  font-weight: 500;
  font-size: clamp(2rem, 3.6vw, 2.75rem);
  line-height: 1.05;
  letter-spacing: -0.012em;
}
.hero-card h1::after {
  content: "";
  display: block;
  width: 3rem;
  height: 1px;
  background: var(--accent);
  margin: 0.75rem auto 0 0;
}

.tagline {
  font-family: var(--serif);
  font-size: clamp(0.98rem, 1.25vw, 1.08rem);
  font-style: italic;
  color: var(--ink-soft);
  margin: 0.85rem 0 1.1rem;
  line-height: 1.45;
}

.cta-row {
  display: flex;
  gap: 0.55rem;
  flex-wrap: wrap;
  justify-content: flex-start;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.72rem 1.15rem;
  font-family: var(--sans);
  font-size: 0.9rem;
  letter-spacing: 0.01em;
  text-decoration: none;
  border-radius: 2px;
  border: 1px solid transparent;
  transition: transform 160ms var(--ease), background-color 160ms var(--ease), color 160ms var(--ease), border-color 160ms var(--ease), box-shadow 160ms var(--ease);
}
.btn-primary {
  background: var(--ink);
  color: var(--bg);
  border-color: var(--ink);
  box-shadow: 0 2px 0 var(--accent);
}
.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--accent-deep);
  border-color: var(--accent-deep);
  color: var(--bg);
  transform: translateY(-1px);
}
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--ink);
}
.btn-ghost:hover,
.btn-ghost:focus-visible {
  background: var(--ink);
  color: var(--bg);
  transform: translateY(-1px);
}

/* ─── Ornament ─────────────────────────────────────────────────────────── */

.ornament {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  width: var(--container);
  margin: clamp(3rem, 7vw, 5rem) auto;
  color: var(--accent);
  font-family: var(--serif);
  font-size: 1.4rem;
}
.ornament::before,
.ornament::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--rule), transparent);
}

/* ─── Section scaffolding ─────────────────────────────────────────────── */

section {
  width: var(--container);
  margin: 0 auto;
  scroll-margin-top: calc(var(--nav-h) + 1rem);
  padding: clamp(1rem, 3vw, 2rem) 0;
  position: relative;
}

section > .chapter {
  position: absolute;
  top: clamp(1rem, 3vw, 2rem);
  left: -0.5rem;
  font-family: var(--serif);
  font-style: italic;
  font-size: 1.05rem;
  color: var(--accent);
  letter-spacing: 0.05em;
}
@media (min-width: 80rem) {
  section > .chapter {
    left: -3rem;
    font-size: 1.15rem;
  }
}

section > h2 {
  max-width: var(--measure);
  margin: 0 0 1.5rem;
}
section > h2::after {
  content: "";
  display: block;
  width: 3rem;
  height: 1px;
  background: var(--accent);
  margin-top: 0.85rem;
}

.section-intro {
  max-width: var(--measure);
  font-size: 1.08rem;
  color: var(--ink-soft);
  margin-bottom: 2.4rem;
}

/* ─── What ─────────────────────────────────────────────────────────────── */

.prose {
  max-width: var(--measure);
  font-size: 1.08rem;
  color: var(--ink-soft);
}
.prose code {
  background: color-mix(in srgb, var(--accent) 14%, transparent);
  padding: 0.05em 0.35em;
  border-radius: 2px;
  font-size: 0.92em;
}
.prose .lede {
  font-size: 1.18rem;
  color: var(--ink);
}
.prose .lede::first-letter {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 4.2em;
  line-height: 0.86;
  float: left;
  margin: 0.05em 0.12em 0 0;
  color: var(--accent-deep);
  padding: 0.05em 0.05em 0 0;
}

.prose blockquote {
  margin: 2.4rem 0 0;
  padding: 1rem 0 1rem 1.5rem;
  border-left: 2px solid var(--accent);
  font-family: var(--serif);
  font-style: italic;
  font-size: 1.4rem;
  color: var(--ink);
}
.prose blockquote p { margin: 0; }

/* ─── Features ─────────────────────────────────────────────────────────── */

.cards {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(18rem, 100%), 1fr));
  gap: 1.25rem;
}
.card {
  position: relative;
  padding: 1.6rem 1.4rem 1.4rem;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-top: 2px solid var(--accent);
  border-radius: 2px;
  transition: transform 220ms var(--ease), box-shadow 220ms var(--ease), border-color 220ms var(--ease);
}
.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}
.card-mark {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--ink-muted);
  margin-bottom: 0.85rem;
  text-transform: uppercase;
}
.card h3 {
  margin: 0 0 0.55rem;
}
.card p {
  margin: 0;
  font-size: 0.96rem;
  color: var(--ink-soft);
  line-height: 1.55;
}

/* ─── Dashboard tour ───────────────────────────────────────────────────── */

.tour {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: center;
  margin: 2.5rem 0;
}
.tour.reverse { grid-template-columns: 1.4fr 1fr; }
.tour.reverse .tour-text { order: 2; }
.tour.reverse .tour-figure { order: 1; }

.tour-text h3 {
  font-size: 1.45rem;
  margin-bottom: 0.7rem;
}
.tour-text h3::after {
  content: "";
  display: block;
  width: 2rem;
  height: 1px;
  background: var(--accent);
  margin-top: 0.6rem;
}
.tour-text p {
  margin: 0;
  color: var(--ink-soft);
}

.tour-figure {
  margin: 0;
  position: relative;
  padding: 0.6rem;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 3px;
  box-shadow: var(--shadow);
  transition: transform 320ms var(--ease), box-shadow 320ms var(--ease);
}
.tour-figure::before {
  content: "";
  position: absolute;
  inset: 0;
  border: 1px solid var(--accent-glow);
  border-radius: 3px;
  pointer-events: none;
  opacity: 0;
  transition: opacity 320ms var(--ease);
}
.tour-figure:hover {
  transform: translateY(-3px);
  box-shadow: 0 30px 60px -30px rgba(27, 23, 20, 0.4), 0 6px 12px -6px rgba(27, 23, 20, 0.15);
}
.tour-figure:hover::before { opacity: 1; }
.tour-figure img {
  border-radius: 2px;
  display: block;
}

/* ─── Get started ──────────────────────────────────────────────────────── */

#get-started p { max-width: var(--measure); color: var(--ink-soft); }
#get-started code {
  background: color-mix(in srgb, var(--accent) 14%, transparent);
  padding: 0.05em 0.35em;
  border-radius: 2px;
  font-size: 0.92em;
}

.code {
  display: block;
  position: relative;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-left: 2px solid var(--accent);
  border-radius: 3px;
  padding: 1.1rem 1.25rem 1.15rem 2.6rem;
  margin: 1.2rem 0 1.6rem;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--ink);
  box-shadow: var(--shadow-soft);
  white-space: pre;
}
.code .prompt {
  position: absolute;
  left: 1rem;
  top: 1.1rem;
  color: var(--accent);
  font-weight: 600;
  user-select: none;
}
.code .comment { color: var(--ink-muted); font-style: italic; }

.quiet { color: var(--ink-muted); font-size: 0.95rem; }

/* ─── Footer ───────────────────────────────────────────────────────────── */

footer {
  width: var(--container);
  margin: clamp(3.5rem, 8vw, 6rem) auto 3rem;
  text-align: center;
  font-size: 0.88rem;
  color: var(--ink-muted);
}
.foot-rule {
  width: 6rem;
  height: 1px;
  background: var(--accent);
  margin: 0 auto 1.5rem;
  position: relative;
}
.foot-rule::before, .foot-rule::after {
  content: "✦";
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  color: var(--accent);
  font-size: 0.7rem;
}
.foot-rule::before { left: -1.2rem; }
.foot-rule::after  { right: -1.2rem; }
footer p { margin: 0 0 0.4rem; }
footer .colophon {
  font-family: var(--serif);
  font-style: italic;
  font-size: 0.85rem;
  color: var(--ink-muted);
}
footer a { color: var(--ink-soft); }

/* ─── Reveal animation ─────────────────────────────────────────────────── */

@keyframes rise {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}

[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 700ms var(--ease), transform 700ms var(--ease);
  will-change: opacity, transform;
}
[data-reveal].in {
  opacity: 1;
  transform: none;
}

/* ─── Responsive ───────────────────────────────────────────────────────── */

@media (max-width: 60rem) {
  .tour, .tour.reverse {
    grid-template-columns: 1fr;
  }
  .tour.reverse .tour-text { order: 0; }
  .tour.reverse .tour-figure { order: 0; }
}

@media (max-width: 44rem) {
  .site-nav { gap: 0.5rem; padding: 0.55rem 0.85rem; }
  .site-nav nav { gap: 0.75rem; font-size: 0.82rem; }
  .site-nav nav a { font-size: 0.82rem; }
  .brand-name { display: none; }

  #hero {
    min-height: auto;
    grid-template-rows: auto auto;
    align-items: stretch;
  }
  .hero-banner {
    position: relative;
    inset: auto;
    aspect-ratio: 16 / 11;
    background: var(--bg);
  }
  .hero-banner img {
    object-position: center 28%;
  }
  .hero-scrim,
  [data-theme="dark"] .hero-scrim {
    background:
      linear-gradient(180deg, transparent 55%, color-mix(in srgb, var(--bg) 90%, transparent) 100%);
  }
  .hero-card {
    margin: 0;
    width: 100%;
    max-width: none;
    padding: 1.75rem 1.1rem 2rem;
    border: none;
    border-radius: 0;
    box-shadow: none;
    background: var(--bg);
    backdrop-filter: none;
    text-align: left;
  }
  .hero-card h1 { font-size: clamp(2.4rem, 12vw, 3.4rem); }
  .hero-card h1::after { margin-left: 0; }
  .tagline { font-size: 1.05rem; }
  .cta-row { gap: 0.5rem; justify-content: flex-start; }
  .btn { padding: 0.65rem 1rem; font-size: 0.88rem; }

  .prose .lede::first-letter { font-size: 3.4em; }
  footer { width: 92vw; }
}

/* ─── Reduced motion ───────────────────────────────────────────────────── */

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
}