/* ============================================================
   The AI Tech Hub — design system
   Concept: a field-guide / specimen-catalog for AI tools.
   Ink-navy ground, warm paper cards, amber + teal accent pair,
   mono "spec strip" on every tool card like a museum label.
   ============================================================ */

:root {
  --ink: #12141c;
  --ink-2: #1b1e29;
  --ink-3: #262a38;
  --paper: #f5f1e8;
  --paper-dim: #e8e2d4;
  --amber: #e8a93d;
  --amber-dim: #b9822a;
  --teal: #5fbfb3;
  --text-hi: #f3f1ea;
  --text-lo: #a8adbd;
  --text-faint: #6b7080;
  --line: rgba(243, 241, 234, 0.1);
  --line-strong: rgba(243, 241, 234, 0.2);

  --display: "Fraunces", Georgia, serif;
  --body: "Public Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;

  --radius: 10px;
  --max-w: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--ink);
  color: var(--text-hi);
  font-family: var(--body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a { color: inherit; text-decoration: none; }

h1, h2, h3, h4 {
  font-family: var(--display);
  font-weight: 600;
  line-height: 1.15;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
}

p { margin: 0 0 1em; color: var(--text-lo); }

.wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- utility label / mono strip ---------- */
.spec {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-faint);
}

/* ---------- header / nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(18, 20, 28, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--display);
  font-weight: 600;
  font-size: 19px;
  color: var(--text-hi);
}
.brand .mark {
  width: 30px; height: 30px;
  border-radius: 6px;
  background: linear-gradient(135deg, var(--amber), var(--teal));
  display: flex; align-items: center; justify-content: center;
  color: var(--ink);
  font-weight: 800;
  font-family: var(--body);
  font-size: 15px;
}
.nav-links {
  display: flex;
  gap: 28px;
  list-style: none;
  margin: 0; padding: 0;
  font-size: 14px;
}
.nav-links a {
  color: var(--text-lo);
  transition: color 0.15s ease;
}
.nav-links a:hover, .nav-links a.active { color: var(--text-hi); }
.nav-cta {
  border: 1px solid var(--line-strong);
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 13px;
  white-space: nowrap;
}
.nav-cta:hover { border-color: var(--amber); color: var(--amber); }
.nav-toggle { display: none; }

@media (max-width: 780px) {
  .nav-links { display: none; }
  .nav-toggle {
    display: block;
    background: none; border: 1px solid var(--line-strong);
    color: var(--text-hi); border-radius: 8px; padding: 6px 10px;
    font-size: 18px;
  }
  .nav-links.open {
    display: flex; flex-direction: column;
    position: absolute; top: 64px; left: 0; right: 0;
    background: var(--ink-2); padding: 20px 24px; gap: 16px;
    border-bottom: 1px solid var(--line);
  }
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-size: 14px; font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
}
.btn-primary { background: var(--amber); color: var(--ink); }
.btn-primary:hover { background: #f0b658; }
.btn-ghost { border-color: var(--line-strong); color: var(--text-hi); }
.btn-ghost:hover { border-color: var(--teal); color: var(--teal); }

/* ---------- page hero (interior pages) ---------- */
.page-hero {
  padding: 64px 0 40px;
  border-bottom: 1px solid var(--line);
}
.page-hero .spec { margin-bottom: 14px; }
.page-hero h1 { font-size: clamp(30px, 5vw, 44px); color: var(--text-hi); }
.page-hero .lede { font-size: 17px; max-width: 640px; }

/* ---------- generic section ---------- */
section { padding: 56px 0; }
.section-head { margin-bottom: 32px; max-width: 640px; }
.section-head .spec { margin-bottom: 10px; }
.section-head h2 { font-size: clamp(24px, 3.4vw, 32px); color: var(--text-hi); }

/* ---------- cards (paper surface) ---------- */
.card {
  background: var(--paper);
  color: var(--ink);
  border-radius: var(--radius);
  padding: 22px;
}
.card p { color: #4a4636; }

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 48px 0 28px;
  margin-top: 40px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 32px;
}
.footer-col h4 {
  font-family: var(--body);
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-faint);
  margin-bottom: 14px;
}
.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin-bottom: 10px; }
.footer-col a { color: var(--text-lo); font-size: 14px; }
.footer-col a:hover { color: var(--amber); }
.footer-bottom {
  border-top: 1px solid var(--line);
  padding-top: 20px;
  font-size: 13px;
  color: var(--text-faint);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px;
}
@media (max-width: 780px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

/* ---------- simple content pages (about/privacy/terms) ---------- */
.prose { max-width: 720px; }
.prose h2 { font-size: 22px; margin-top: 40px; color: var(--text-hi); }
.prose p, .prose li { color: var(--text-lo); font-size: 15.5px; }
.prose ul { padding-left: 20px; }

/* ---------- contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: start;
}
@media (max-width: 780px) { .contact-grid { grid-template-columns: 1fr; } }

.field { margin-bottom: 18px; }
.field label {
  display: block; font-size: 13px; margin-bottom: 6px;
  color: var(--text-lo); font-family: var(--mono);
  text-transform: uppercase; letter-spacing: 0.03em;
}
.field input, .field textarea {
  width: 100%;
  background: var(--ink-2);
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  padding: 12px 14px;
  color: var(--text-hi);
  font-family: var(--body);
  font-size: 15px;
}
.field input:focus, .field textarea:focus {
  outline: 2px solid var(--teal);
  outline-offset: 1px;
}
.field textarea { min-height: 130px; resize: vertical; }
.form-note { font-size: 13px; color: var(--text-faint); margin-top: 10px; }

/* ---------- tools directory ---------- */
.tools-toolbar {
  display: flex; gap: 12px; flex-wrap: wrap;
  align-items: center;
  margin-bottom: 28px;
}
.tools-search {
  flex: 1 1 260px;
  background: var(--ink-2);
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  padding: 11px 18px;
  color: var(--text-hi);
  font-family: var(--body);
  font-size: 14px;
}
.tools-search:focus { outline: 2px solid var(--teal); }

.chip-row {
  display: flex; gap: 8px; flex-wrap: wrap;
  margin-bottom: 32px;
}
.chip {
  font-family: var(--mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  color: var(--text-lo);
  background: none;
  cursor: pointer;
}
.chip:hover { border-color: var(--teal); color: var(--teal); }
.chip.active { background: var(--amber); border-color: var(--amber); color: var(--ink); }

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 18px;
}

.tool-card {
  background: var(--paper);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}
.tool-card .spec-strip {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.03em;
  text-transform: uppercase;
  background: var(--ink);
  color: var(--teal);
  padding: 7px 14px;
  display: flex;
  justify-content: space-between;
}
.tool-card .spec-strip .dot {
  color: var(--amber);
}
.tool-card .tool-body { padding: 18px 18px 20px; flex: 1; display: flex; flex-direction: column; }
.tool-card h3 { font-size: 18px; color: var(--ink); margin-bottom: 6px; }
.tool-card p { color: #4a4636; font-size: 14px; flex: 1; }
.tool-card .tool-link {
  margin-top: 10px;
  font-size: 13px; font-weight: 700;
  color: var(--amber-dim);
}
.tool-card .tool-link:hover { color: var(--ink); }
.tools-empty {
  display: none;
  padding: 60px 0; text-align: center;
  color: var(--text-faint);
}
.tools-count { font-size: 13px; color: var(--text-faint); margin-bottom: 6px; }