/* ============================================================
   Nordic Theory Labs — shared subpage stylesheet
   Used by: blog, about, press, contact, changelog, 404
   Matches the language established in index.html.
   ============================================================ */

:root {
  --paper:        #F1EEE6;
  --paper-soft:   #E9E5DA;
  --paper-warm:   #EFEAD8;
  --ink:          #0E1620;
  --ink-soft:     #2A323E;
  --ink-mute:     #6B7280;
  --line:         rgba(14, 22, 32, 0.12);
  --line-soft:    rgba(14, 22, 32, 0.06);

  --aurora-a:     oklch(0.72 0.13 175);
  --aurora-b:     oklch(0.62 0.18 285);
  --aurora-c:     oklch(0.78 0.10 220);
  --accent:       oklch(0.55 0.13 220);
  --accent-soft:  oklch(0.92 0.04 220);
  --pos:          oklch(0.62 0.15 145);

  --serif: "Instrument Serif", "Times New Roman", serif;
  --sans:  "Manrope", "Helvetica Neue", system-ui, sans-serif;
  --mono:  "JetBrains Mono", ui-monospace, monospace;

  --col-pad: clamp(20px, 4vw, 56px);
  --max:    1320px;
  --max-wide: 1480px;
}

*, *::before, *::after { box-sizing: border-box; }
html, body { background: var(--paper); color: var(--ink); }
body {
  margin: 0;
  font-family: var(--sans);
  font-weight: 400;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
::selection { background: var(--ink); color: var(--paper); }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
img { display: block; max-width: 100%; }

/* paper grain */
body::before {
  content: "";
  position: fixed; inset: 0;
  background-image: radial-gradient(rgba(14,22,32,0.035) 1px, transparent 1.4px);
  background-size: 3px 3px;
  mix-blend-mode: multiply;
  pointer-events: none;
  z-index: 1;
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--col-pad);
  position: relative;
  z-index: 2;
}
.wrap-wide { max-width: var(--max-wide); }

/* ───────────────────────── NAV ───────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(14px) saturate(1.1);
  -webkit-backdrop-filter: blur(14px) saturate(1.1);
  background: color-mix(in oklab, var(--paper) 80%, transparent);
  border-bottom: 1px solid var(--line-soft);
}
.nav-inner {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 32px;
  padding: 16px 0;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 600; letter-spacing: -0.01em; }
.brand-mark {
  width: 30px; height: 30px;
  background: var(--ink);
  border-radius: 7px;
  flex: 0 0 auto;
  display: inline-block;
}
.brand-mark svg { display: block; width: 100%; height: 100%; }
.brand-mark .sig-frame { stroke: var(--paper); opacity: 0.55; }
.brand-mark .sig-axis  { stroke: var(--paper); opacity: 0.18; }
.brand-mark .sig-wave  { stroke: var(--paper); }
.brand-mark .sig-dot   { fill: var(--accent); }
.brand-name { font-size: 15px; }
.brand-name em { font-family: var(--serif); font-style: italic; font-weight: 400; }

.nav-links { display: flex; gap: 28px; justify-self: center; }
.nav-links a {
  font-size: 13px; letter-spacing: 0.02em;
  color: var(--ink-soft);
  position: relative; padding: 4px 0;
}
.nav-links a:hover { color: var(--ink); }
.nav-links a.active { color: var(--ink); font-weight: 500; }
.nav-links a::after {
  content: ""; position: absolute; left: 0; right: 100%; bottom: 0; height: 1px;
  background: var(--ink); transition: right 0.25s ease;
}
.nav-links a:hover::after,
.nav-links a.active::after { right: 0; }
.nav-meta {
  display: flex; align-items: center; gap: 16px;
  font-family: var(--mono); font-size: 11px;
  color: var(--ink-mute); letter-spacing: 0.04em;
}
.pulse {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--pos);
  box-shadow: 0 0 0 0 oklch(0.62 0.15 145 / 0.6);
  animation: pulse 2.4s infinite;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 oklch(0.62 0.15 145 / 0.6); }
  70% { box-shadow: 0 0 0 10px oklch(0.62 0.15 145 / 0); }
  100% { box-shadow: 0 0 0 0 oklch(0.62 0.15 145 / 0); }
}

/* breadcrumb (centered when used) */
.crumb {
  justify-self: center;
  display: flex; align-items: center; gap: 10px;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.08em;
  color: var(--ink-mute); text-transform: uppercase;
}
.crumb a:hover { color: var(--ink); }
.crumb .sep { opacity: 0.4; }
.crumb .cur { color: var(--ink); font-weight: 500; }

/* ───────────────────────── PAGE HEAD ───────────────────────── */
.page-head {
  position: relative;
  padding: clamp(60px, 9vw, 120px) 0 clamp(40px, 5vw, 64px);
  isolation: isolate;
  overflow: hidden;
}
.aurora {
  position: absolute; inset: -20%;
  z-index: -1;
  filter: blur(80px) saturate(1.3);
  opacity: 0.42;
  pointer-events: none;
}
.aurora::before, .aurora::after {
  content: ""; position: absolute; border-radius: 50%;
}
.aurora::before {
  width: 50%; height: 60%; left: 5%; top: -5%;
  background: radial-gradient(circle, var(--aurora-a), transparent 60%);
  animation: drift1 18s ease-in-out infinite alternate;
}
.aurora::after {
  width: 45%; height: 55%; right: -5%; top: 10%;
  background: radial-gradient(circle, var(--aurora-b), transparent 60%);
  animation: drift2 22s ease-in-out infinite alternate;
}
@keyframes drift1 { 0%{transform:translate(0,0) scale(1);} 100%{transform:translate(6%,4%) scale(1.12);} }
@keyframes drift2 { 0%{transform:translate(0,0) scale(1);} 100%{transform:translate(-4%,-4%) scale(1.08);} }

.eyebrow {
  display: flex; align-items: center; gap: 12px;
  font-family: var(--mono); font-size: 11px;
  letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--ink-mute);
  margin-bottom: 28px;
}
.eyebrow .bar { width: 32px; height: 1px; background: var(--ink-mute); }

.page-title {
  margin: 0;
  font-size: clamp(40px, 6.4vw, 96px);
  line-height: 0.98;
  letter-spacing: -0.03em;
  font-weight: 500;
  max-width: 18ch;
}
.page-title em {
  font-family: var(--serif);
  font-style: italic;
  font-weight: 400;
  letter-spacing: -0.02em;
}
.page-sub {
  font-size: clamp(16px, 1.4vw, 19px);
  line-height: 1.55;
  color: var(--ink-soft);
  max-width: 56ch;
  margin: 28px 0 0;
}

/* ───────────────────────── BUTTONS ───────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 13px 22px;
  border-radius: 999px;
  font-size: 14px; font-weight: 500;
  letter-spacing: -0.005em;
  transition: transform 0.15s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
  cursor: pointer;
}
.btn:hover { transform: translateY(-1px); }
.btn-ink { background: var(--ink); color: var(--paper); }
.btn-ink:hover { background: var(--ink-soft); }
.btn-ghost { border: 1px solid var(--line); color: var(--ink); }
.btn-ghost:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.btn .arrow { transition: transform 0.2s ease; }
.btn:hover .arrow { transform: translateX(3px); }

/* small chip / tag */
.tag {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 5px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--mono); font-size: 10.5px;
  letter-spacing: 0.1em; text-transform: uppercase;
  color: var(--ink-soft);
  background: color-mix(in oklab, var(--paper) 70%, transparent);
}
.tag-ink { background: var(--ink); color: var(--paper); border-color: var(--ink); }

/* ───────────────────────── SECTION SHELL ───────────────────────── */
section { padding: clamp(60px, 8vw, 110px) 0; position: relative; }
.section-head {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 40px;
  margin-bottom: 56px;
  align-items: end;
}
.section-label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-mute);
}
.section-title {
  font-size: clamp(32px, 4.2vw, 56px);
  line-height: 1.02;
  letter-spacing: -0.03em;
  font-weight: 500;
  margin: 0;
  max-width: 22ch;
}
.section-title em { font-family: var(--serif); font-style: italic; font-weight: 400; }

/* ───────────────────────── FOOTER ───────────────────────── */
footer.foot {
  border-top: 1px solid var(--line);
  padding: 64px 0 32px;
  margin-top: 80px;
  background: var(--paper-soft);
}
.foot-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 56px;
}
.foot-grid .col h4 {
  font-family: var(--mono);
  font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--ink-mute);
  margin: 0 0 14px;
  font-weight: 500;
}
.foot-grid .col a, .foot-grid .col p {
  display: block;
  font-size: 14px; color: var(--ink-soft);
  margin: 0 0 6px;
  line-height: 1.5;
}
.foot-grid .col p em { font-family: var(--serif); font-style: italic; }
.foot-grid .col a:hover { color: var(--ink); }
.foot-grid .col strong { color: var(--ink); font-weight: 600; }

.foot-bottom {
  border-top: 1px solid var(--line);
  padding-top: 24px;
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 16px;
  font-family: var(--mono); font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--ink-mute);
}
.foot-bottom a:hover { color: var(--ink); }
.foot-bottom .center { text-align: center; }
.foot-bottom .right { text-align: right; }

/* ───────────────────────── RESPONSIVE ───────────────────────── */
@media (max-width: 880px) {
  .nav-inner { grid-template-columns: auto auto; }
  .nav-links { display: none; }
  .section-head { grid-template-columns: 1fr; gap: 16px; }
  .foot-grid { grid-template-columns: 1fr 1fr; }
  .foot-bottom { grid-template-columns: 1fr; text-align: left; }
  .foot-bottom .center, .foot-bottom .right { text-align: left; }
}