/* ============================================================
   SHAKY FOUNDATION — Shared Styles
   System dark/light mode via prefers-color-scheme
   ============================================================ */

/* FONTS */
@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:ital,wght@0,400;0,700;0,900;1,400;1,700&family=IBM+Plex+Mono:wght@300;400;500&family=Crimson+Pro:ital,wght@0,300;0,400;1,300;1,400&display=swap');

/* ---- LIGHT MODE (default) ---- */
:root {
  --bg:       #f5f0e8;   /* warm parchment */
  --bg-alt:   #ede6d6;   /* slightly darker parchment */
  --bg-deep:  #0d0c0a;   /* near-black ink */
  --text:     #0d0c0a;
  --text-mid: #6b6254;
  --text-faint:#c8bfa8;
  --border:   #d4c9b4;
  --rust:     #9b3a1a;
  --rust-dim: #7a2e14;
  --nav-bg:   #f5f0e8;
  --card-bg:  #f5f0e8;
  --card-hover-bg: #0d0c0a;
  --card-hover-text: #f5f0e8;
  --invert-bg: #0d0c0a;
  --invert-text: #f5f0e8;
  --invert-text-mid: rgba(245,240,232,0.65);
  --invert-border: rgba(255,255,255,0.1);
  --pull-quote-text: #f5f0e8;
  --mono: 'IBM Plex Mono', monospace;
  --serif: 'Crimson Pro', Georgia, serif;
  --display: 'Playfair Display', Georgia, serif;
}

/* ---- DARK MODE ---- */
@media (prefers-color-scheme: dark) {
  :root {
    --bg:       #19170f;   /* deep warm dark, not pure black */
    --bg-alt:   #221f14;   /* slightly lighter dark */
    --bg-deep:  #100e09;   /* deepest layer */
    --text:     #e8e0cc;   /* warm off-white — NOT bright white */
    --text-mid: #9e9282;
    --text-faint:#5a5248;
    --border:   #2e2a1e;
    --rust:     #c4502a;   /* slightly brighter rust for contrast on dark */
    --rust-dim: #9b3a1a;
    --nav-bg:   #19170f;
    --card-bg:  #211e13;
    --card-hover-bg: #c4502a;
    --card-hover-text: #f5f0e8;
    --invert-bg: #100e09;
    --invert-text: #e8e0cc;
    --invert-text-mid: rgba(232,224,204,0.6);
    --invert-border: rgba(232,224,204,0.08);
    --pull-quote-text: #e8e0cc;
  }
}

/* ============================================================
   RESET & BASE
   ============================================================ */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.7;
  overflow-x: hidden;
  transition: background 0.3s, color 0.3s;
}

/* GRAIN TEXTURE */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 512 512' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.04'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 9999;
  opacity: 0.35;
}

/* ============================================================
   NAVIGATION
   ============================================================ */
nav {
  position: fixed;
  top: 0;
  width: 100%;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.2rem 3rem;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border);
  transition: background 0.3s, border-color 0.3s;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.nav-logo {
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 400;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--rust);
  text-decoration: none;
}
.nav-logo span { color: var(--text-mid); }

.nav-links {
  display: flex;
  gap: 2.5rem;
  list-style: none;
  align-items: center;
}
.nav-links a {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-mid);
  text-decoration: none;
  transition: color 0.2s;
}
.nav-links a:hover,
.nav-links a.active { color: var(--rust); }

/* ── TOPIC NAV BUTTONS ── */
.nav-topic {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
  font-family: var(--mono);
  font-size: 0.6rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.35rem 0.75rem;
  border: 1px solid transparent;
  transition: background 0.2s, color 0.2s, border-color 0.2s;
  white-space: nowrap;
  line-height: 1;
}
.nav-topic-num {
  font-size: 0.52rem;
  opacity: 0.5;
  letter-spacing: 0.08em;
}
/* 001 Infinity — cool, geometric, ink-outlined */
.nav-topic-001 {
  color: var(--text-mid);
  border-color: var(--border);
  background: transparent;
}
.nav-topic-001:hover,
.nav-topic-001.active {
  background: var(--text);
  color: var(--bg);
  border-color: var(--text);
}
/* 002 Alignment — warm, ethical, rust-accented */
.nav-topic-002 {
  color: var(--rust);
  border-color: var(--rust);
  background: transparent;
}
.nav-topic-002:hover,
.nav-topic-002.active {
  background: var(--rust);
  color: #f5f0e8;
  border-color: var(--rust);
}

/* ============================================================
   PAGE HEADER (shared across inner pages)
   ============================================================ */
.page-header {
  padding: 10rem 3rem 4rem;
  border-bottom: 1px solid var(--border);
}
.page-header-dark {
  padding: 10rem 3rem 5rem;
  background: var(--invert-bg);
  color: var(--invert-text);
}

.eyebrow {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--rust);
  margin-bottom: 1rem;
}

/* ============================================================
   FOOTER
   ============================================================ */
footer {
  background: var(--invert-bg);
  color: var(--invert-text);
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2rem;
  padding: 1.6rem 3rem 1.2rem;
  align-items: start;
}
.footer-brand p {
  font-size: 0.78rem;
  font-weight: 300;
  line-height: 1.6;
  color: var(--invert-text-mid);
  margin-top: 0.4rem;
  max-width: 35ch;
}
.footer-col h4 {
  font-family: var(--mono);
  font-size: 0.58rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--rust);
  margin-bottom: 0.5rem;
}
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 0.3rem; }
.footer-col a {
  font-size: 0.78rem;
  color: var(--invert-text-mid);
  text-decoration: none;
  transition: color 0.2s;
}
.footer-col a:hover { color: var(--invert-text); }

.footer-bottom {
  background: var(--invert-bg);
  border-top: 1px solid var(--invert-border);
  padding: 0.6rem 3rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-bottom p {
  font-family: var(--mono);
  font-size: 0.58rem;
  letter-spacing: 0.08em;
  color: var(--text-faint);
}

/* ============================================================
   BUTTONS & LINKS
   ============================================================ */
.btn-primary {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--bg);
  background: var(--text);
  padding: 1rem 2rem;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}
.btn-primary:hover { background: var(--rust); color: #f5f0e8; }

/* ============================================================
   SECTION LABELS
   ============================================================ */
.section-label {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-faint);
  margin-bottom: 1rem;
}

/* ============================================================
   TOPIC CARDS
   ============================================================ */
.topic-card {
  background: var(--card-bg);
  padding: 2.5rem;
  text-decoration: none;
  color: var(--text);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: background 0.2s, color 0.2s;
  border: 1px solid var(--border);
}
.topic-card:hover {
  background: var(--card-hover-bg);
  color: var(--card-hover-text);
  border-color: var(--card-hover-bg);
}
.topic-card:hover .topic-desc { color: rgba(245,240,232,0.65); }
.topic-card:hover .topic-tag  { color: rgba(245,240,232,0.4); border-color: rgba(245,240,232,0.2); }
.topic-card:hover .topic-footer { border-color: rgba(255,255,255,0.1); }
.topic-card:hover .topic-arrow { color: #f5f0e8; }

.topic-num {
  font-family: var(--mono);
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  color: var(--text-faint);
}
.topic-name {
  font-family: var(--display);
  font-size: 1.6rem;
  font-weight: 700;
  line-height: 1.2;
}
.topic-desc {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-mid);
}
.topic-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: auto;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.topic-tag {
  font-family: var(--mono);
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
  border: 1px solid var(--border);
  padding: 0.25rem 0.6rem;
}
.topic-arrow { font-size: 1.2rem; color: var(--text-mid); }
.topic-card.placeholder { opacity: 0.4; cursor: default; pointer-events: none; }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 768px) {
  nav { padding: 1rem 1.5rem; }
  .nav-links { gap: 1.5rem; }
  footer { grid-template-columns: 1fr 1fr; }
  .page-header, .page-header-dark { padding: 8rem 1.5rem 3rem; }
}