/* Nexoma Books — books.nexomalabs.com
   Brand tokens are aligned with www.nexomalabs.com so the two sites read as one company. */

:root {
  --bg: #050816;
  --bg-alt: #0b1020;
  --panel: #101728;
  --panel-2: #0d1424;
  --line: rgba(180, 183, 195, 0.18);
  --line-strong: rgba(180, 183, 195, 0.32);
  --text: #ffffff;
  --muted: #b4b7c3;
  --accent: #3b82f6;
  --accent-2: #7c3aed;
  --ok: #34d399;
  --warn: #fbbf24;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.38);
  --radius: 14px;
  --radius-sm: 9px;
}

html.light {
  --bg: #f3f5f8;
  --bg-alt: #ffffff;
  --panel: #ffffff;
  --panel-2: #f7f9fc;
  --line: #dbe2ed;
  --line-strong: #c2cede;
  --text: #17202b;
  --muted: #4d627a;
  --accent: #1f6feb;
  --accent-2: #7c3aed;
  --ok: #0f9d63;
  --warn: #b45309;
  --shadow: 0 18px 40px rgba(18, 27, 40, 0.09);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 12% 8%, rgba(59, 130, 246, 0.13), transparent 40%),
    radial-gradient(circle at 88% 92%, rgba(124, 58, 237, 0.14), transparent 42%),
    linear-gradient(180deg, var(--bg), var(--bg-alt));
  background-attachment: fixed;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, .brand, .footer-brand {
  font-family: "Space Grotesk", "Inter", "Segoe UI", sans-serif;
  line-height: 1.2;
  letter-spacing: -0.015em;
}

h1 { font-size: clamp(2rem, 4.4vw, 3rem); margin: 0 0 0.6rem; }
h2 { font-size: clamp(1.4rem, 2.6vw, 1.9rem); margin: 0 0 0.9rem; }
h3 { font-size: 1.12rem; margin: 0 0 0.5rem; }

p { margin: 0 0 1rem; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { width: min(1120px, calc(100% - 2.5rem)); margin: 0 auto; }
.narrow { width: min(780px, calc(100% - 2.5rem)); margin: 0 auto; }

.muted { color: var(--muted); }
.small { font-size: 0.875rem; }
.center { text-align: center; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #fff;
  padding: 0.6rem 1rem;
  z-index: 100;
}
.skip-link:focus { left: 0; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(14px);
}

.nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--text);
  font-size: 0.95rem;
  letter-spacing: 0.08em;
  white-space: nowrap;
}
.brand:hover { text-decoration: none; }
.brand img { display: block; border-radius: 6px; }

.site-menu {
  display: flex;
  align-items: center;
  gap: 1.15rem;
  margin-left: auto;
  font-size: 0.9rem;
}
.site-menu a { color: var(--muted); white-space: nowrap; }
.site-menu a:hover { color: var(--text); text-decoration: none; }
.site-menu a[aria-current="page"] { color: var(--text); font-weight: 600; }
.site-menu .ext { display: none; }

.theme-toggle,
.menu-toggle {
  background: transparent;
  border: 1px solid var(--line-strong);
  color: var(--muted);
  border-radius: 999px;
  padding: 0.35rem 0.85rem;
  font: inherit;
  font-size: 0.8rem;
  cursor: pointer;
}
.theme-toggle:hover { color: var(--text); border-color: var(--accent); }

.menu-toggle {
  display: none;
  padding: 0.5rem 0.6rem;
  border-radius: var(--radius-sm);
}
.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 3px 0;
  background: currentColor;
}

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

.hero {
  padding: clamp(2.5rem, 6vw, 4.5rem) 0 2.5rem;
}
.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent);
  margin: 0 0 0.75rem;
}
.lead {
  font-size: clamp(1rem, 1.6vw, 1.15rem);
  color: var(--muted);
  max-width: 62ch;
}

.hero-split {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(1.5rem, 4vw, 3rem);
  align-items: center;
}

/* ---------- sections ---------- */

.section { padding: clamp(2rem, 5vw, 3.25rem) 0; }
.section-line { border-top: 1px solid var(--line); }
.section-title { margin-bottom: 0.35rem; }
.section-sub { color: var(--muted); max-width: 65ch; margin-bottom: 1.6rem; }

/* ---------- cards / grids ---------- */

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.35rem 1.4rem;
  box-shadow: var(--shadow);
}

.grid { display: grid; gap: 1.1rem; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

/* volume cards */

.vol-card {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.3rem;
  transition: border-color 0.18s ease, transform 0.18s ease;
}
.vol-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.vol-card h3 { margin: 0; }
.vol-card .vol-num {
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}
.vol-card .vol-sub { color: var(--muted); font-size: 0.92rem; margin: 0; }
.vol-card .vol-foot {
  margin-top: auto;
  padding-top: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.82rem;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

/* ---------- badges ---------- */

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.22rem 0.6rem;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  color: var(--muted);
  white-space: nowrap;
}
.badge-available { color: var(--ok); border-color: color-mix(in srgb, var(--ok) 45%, transparent); }
.badge-in-production { color: var(--warn); border-color: color-mix(in srgb, var(--warn) 45%, transparent); }
.badge-in-development { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 45%, transparent); }
.badge-planned { color: var(--muted); }

/* ---------- buttons ---------- */

.actions { display: flex; flex-wrap: wrap; gap: 0.65rem; margin-top: 1.4rem; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  border-radius: 999px;
  padding: 0.62rem 1.25rem;
  font-size: 0.92rem;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  box-shadow: 0 10px 26px rgba(59, 130, 246, 0.28);
}
.btn-secondary {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--text);
}
.btn-secondary:hover { border-color: var(--accent); }
.btn-sm { padding: 0.45rem 0.95rem; font-size: 0.84rem; }
.btn[aria-disabled="true"] {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* ---------- cover ---------- */

.cover-frame {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  background: var(--panel-2);
  max-width: 340px;
}
.cover-frame img { display: block; width: 100%; height: auto; }

.cover-placeholder {
  display: grid;
  place-items: center;
  aspect-ratio: 3 / 4;
  max-width: 340px;
  border-radius: var(--radius);
  border: 1px dashed var(--line-strong);
  background: linear-gradient(160deg, var(--panel), var(--panel-2));
  color: var(--muted);
  text-align: center;
  padding: 1.5rem;
}
.cover-placeholder > div { display: grid; gap: 0.55rem; justify-items: center; }
.cover-placeholder .cp-label {
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 600;
}
.cover-placeholder .cp-title {
  font-family: "Space Grotesk", sans-serif;
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.2;
}
.cover-placeholder .cp-rule {
  width: 56px;
  height: 3px;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}
.cover-placeholder .cp-note {
  font-size: 0.8rem;
  color: var(--muted);
}

/* ---------- lists ---------- */

ul.plain { list-style: none; margin: 0; padding: 0; }
ul.plain li { margin-bottom: 0.4rem; font-size: 0.9rem; }
ul.plain a { color: var(--muted); }
ul.plain a:hover { color: var(--text); }

.check { list-style: none; padding: 0; margin: 0 0 1rem; }
.check li {
  position: relative;
  padding-left: 1.5rem;
  margin-bottom: 0.55rem;
  color: var(--muted);
}
.check li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.62em;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  background: var(--accent);
}

/* chapter list */

ol.chapters { counter-reset: ch; list-style: none; margin: 0; padding: 0; }
ol.chapters li {
  counter-increment: ch;
  position: relative;
  padding: 0.55rem 0 0.55rem 3rem;
  border-bottom: 1px solid var(--line);
  color: var(--text);
}
ol.chapters li:last-child { border-bottom: 0; }
ol.chapters li::before {
  content: counter(ch, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0.55rem;
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.85rem;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

/* ---------- meta table ---------- */

.meta-table { width: 100%; border-collapse: collapse; font-size: 0.9rem; }
.meta-table th,
.meta-table td {
  text-align: left;
  padding: 0.55rem 0;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
.meta-table th { color: var(--muted); font-weight: 500; width: 42%; }
.meta-table tr:last-child th,
.meta-table tr:last-child td { border-bottom: 0; }

/* ---------- progression ---------- */

.progression { display: grid; gap: 0.6rem; }
.prog-row {
  display: grid;
  grid-template-columns: 3.5rem 8rem 1fr;
  gap: 1rem;
  align-items: baseline;
  padding: 0.8rem 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--panel-2);
}
.prog-row .pv {
  font-family: "Space Grotesk", sans-serif;
  font-weight: 700;
  color: var(--accent);
}
.prog-row .pverb {
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  color: var(--text);
}
.prog-row .pline { color: var(--muted); font-size: 0.92rem; }

/* ---------- callout ---------- */

.callout {
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  background: var(--panel-2);
  padding: 1.05rem 1.2rem;
  margin: 1.4rem 0;
}
.callout p:last-child { margin-bottom: 0; }
.callout-title {
  font-family: "Space Grotesk", sans-serif;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

/* ---------- errata ---------- */

.errata-empty {
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius);
  padding: 1.6rem;
  text-align: center;
  color: var(--muted);
  background: var(--panel-2);
}

.erratum {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--panel);
  padding: 1.1rem 1.2rem;
  margin-bottom: 0.9rem;
}
.erratum-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 0.6rem;
}
.erratum-id {
  font-family: "Space Grotesk", sans-serif;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--accent);
}
.erratum-loc { font-weight: 600; }
.erratum dl { margin: 0; display: grid; gap: 0.5rem; }
.erratum dt {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 0.15rem;
}
.erratum dd { margin: 0; }
.erratum .was { text-decoration: line-through; color: var(--muted); }
.erratum .now { color: var(--text); }

/* ---------- code ---------- */

code, kbd {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, monospace;
  font-size: 0.88em;
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  border-radius: 5px;
  padding: 0.12em 0.4em;
}

pre {
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 1rem 1.15rem;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.55;
}
pre code { background: none; padding: 0; }

/* ---------- breadcrumbs ---------- */

.crumbs {
  font-size: 0.82rem;
  color: var(--muted);
  padding-top: 1.4rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}
.crumbs a { color: var(--muted); }
.crumbs a:hover { color: var(--text); }
.crumbs span[aria-current] { color: var(--text); }

/* ---------- stats ---------- */

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.stat { background: var(--panel); padding: 1.1rem 1.2rem; }
.stat .n {
  font-family: "Space Grotesk", sans-serif;
  font-size: 1.7rem;
  font-weight: 700;
  display: block;
  line-height: 1.1;
}
.stat .l {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--muted);
}

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

.site-footer {
  border-top: 1px solid var(--line);
  margin-top: 3.5rem;
  padding: 2.5rem 0 1.5rem;
  background: color-mix(in srgb, var(--bg) 60%, transparent);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 2rem;
}
.footer-brand { font-size: 0.95rem; letter-spacing: 0.08em; margin: 0 0 0.4rem; }
.footer-head {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text);
  font-weight: 600;
  margin: 0 0 0.65rem;
}
.footer-legal { margin-top: 2rem; padding-top: 1.25rem; border-top: 1px solid var(--line); }
.footer-legal p { margin: 0; }

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

@media (max-width: 900px) {
  .hero-split { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  .menu-toggle { display: block; margin-left: auto; }
  .site-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin: 0;
    padding: 0.5rem 1.25rem 1rem;
    background: var(--bg-alt);
    border-bottom: 1px solid var(--line);
  }
  .site-menu.open { display: flex; }
  .site-menu a { padding: 0.7rem 0; border-bottom: 1px solid var(--line); }
  .site-menu .ext { display: block; }
  .nav { position: relative; }
  .theme-toggle { order: 3; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .prog-row { grid-template-columns: 2.5rem 1fr; }
  .prog-row .pline { grid-column: 1 / -1; }
  .footer-grid { grid-template-columns: 1fr; gap: 1.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; animation: none !important; }
}

@media print {
  .site-header, .site-footer, .actions, .crumbs { display: none; }
  body { background: #fff; color: #000; }
}