/* ===========================================================
   EQUIVALENT TO — design system
   Motif: the airport/exchange split-flap departure board —
   because every page on this site is a board that translates
   one value into its equivalent somewhere else.
   =========================================================== */

:root {
  /* Color */
  --ink:        #12151c;
  --ink-raised: #1b2029;
  --ink-line:   #2a3040;
  --paper:      #edeae0;
  --amber:      #e8a93a;
  --amber-dim:  #a97c2b;
  --teal:       #4fb3a9;
  --muted:      #8c93a3;
  --danger:     #e1636b;
  --white:      #ffffff;

  /* Type */
  --font-display: 'Space Grotesk', 'Arial Narrow', sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', 'Courier New', monospace;

  /* Layout */
  --max-w: 1120px;
  --radius: 10px;
  --radius-sm: 6px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

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

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

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(1.9rem, 4.2vw, 3rem); }
h2 { font-size: clamp(1.4rem, 2.6vw, 2rem); }
h3 { font-size: 1.15rem; }

p { margin: 0 0 1em; color: var(--paper); }
.muted { color: var(--muted); }

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
}

/* Focus visibility (accessibility, kept even though theme is dark) */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

/* ---------------- Header ---------------- */
.site-header {
  border-bottom: 1px solid var(--ink-line);
  background: var(--ink);
  position: sticky;
  top: 0;
  z-index: 50;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.brand {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--paper);
  display: flex;
  align-items: center;
  gap: 10px;
}
.brand:hover { text-decoration: none; }
.brand .brand-mark {
  width: 30px; height: 30px;
  border-radius: 6px;
  background: linear-gradient(155deg, var(--amber) 0%, var(--amber-dim) 100%);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--ink);
  font-size: 0.85rem;
}
.brand .eq-sign { color: var(--amber); }

nav.main-nav { display: flex; gap: 22px; align-items: center; }
nav.main-nav a {
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 600;
}
nav.main-nav a:hover { color: var(--paper); text-decoration: none; }

/* ---------------- Hero ---------------- */
.hero {
  padding: 64px 0 52px;
  border-bottom: 1px solid var(--ink-line);
  background:
    radial-gradient(ellipse 900px 500px at 15% -10%, rgba(232,169,58,0.10), transparent),
    var(--ink);
}
.hero-eyebrow {
  font-family: var(--font-mono);
  color: var(--amber);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.hero-eyebrow::before {
  content: "";
  width: 8px; height: 8px;
  background: var(--amber);
  border-radius: 50%;
  display: inline-block;
  box-shadow: 0 0 0 3px rgba(232,169,58,0.18);
}
.hero h1 { max-width: 760px; }
.hero .lede { max-width: 620px; font-size: 1.08rem; color: var(--muted); }

/* Split-flap board */
.flipboard {
  margin-top: 36px;
  background: var(--ink-raised);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  padding: 22px 24px;
  max-width: 720px;
}
.flipboard-row { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; font-family: var(--font-mono); }
.flipboard-label { color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.08em; width: 100%; margin-bottom: 10px; }
.flip-chars { display: inline-flex; gap: 3px; flex-wrap: wrap; }
.flip-char {
  display: inline-block;
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink-line);
  border-radius: 4px;
  padding: 6px 4px;
  min-width: 1.05ch;
  text-align: center;
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1;
}
.flip-char.is-amber { color: var(--amber); }
.flip-char.space { border-color: transparent; background: transparent; min-width: 10px; }
.flipboard .arrow-line { color: var(--teal); font-size: 1.1rem; padding: 0 4px; }
.flip-refresh {
  margin-top: 16px;
  font-size: 0.78rem;
  color: var(--muted);
  font-family: var(--font-mono);
}

/* ---------------- Category grid ---------------- */
.section { padding: 56px 0; }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 20px; margin-bottom: 28px; flex-wrap: wrap; }
.section-head p { margin: 0; }

.cat-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}
@media (max-width: 860px) { .cat-grid { grid-template-columns: 1fr; } }

.cat-card {
  background: var(--ink-raised);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  padding: 26px;
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.cat-card:hover { border-color: var(--amber-dim); transform: translateY(-2px); text-decoration: none; }
.cat-card .code {
  font-family: var(--font-mono);
  color: var(--amber);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  margin-bottom: 14px;
  display: block;
}
.cat-card h3 { color: var(--paper); margin-bottom: 8px; }
.cat-card p { color: var(--muted); font-size: 0.92rem; margin-bottom: 0; }

/* ---------------- Board rows (browse / listing lines) ---------------- */
.board {
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--ink-raised);
}
.board-row {
  display: grid;
  grid-template-columns: 90px 1fr auto 26px;
  gap: 14px;
  align-items: center;
  padding: 14px 18px;
  border-bottom: 1px solid var(--ink-line);
  color: var(--paper);
}
.board-row:last-child { border-bottom: none; }
a.board-row:hover { background: rgba(232,169,58,0.06); text-decoration: none; }
.board-row .code {
  font-family: var(--font-mono);
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
}
.board-row .desc { font-size: 0.96rem; }
.board-row .desc .to { color: var(--teal); }
.board-row .result { font-family: var(--font-mono); color: var(--amber); font-weight: 600; white-space: nowrap; }
.board-row .go { color: var(--muted); text-align: right; }
@media (max-width: 640px) {
  .board-row { grid-template-columns: 1fr auto; }
  .board-row .code, .board-row .go { display: none; }
}

/* ---------------- Forms / calculator ---------------- */
.calc {
  background: var(--ink-raised);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  padding: 26px;
}
.calc-grid { display: grid; grid-template-columns: 1fr 1fr 1fr auto; gap: 14px; align-items: end; }
@media (max-width: 760px) { .calc-grid { grid-template-columns: 1fr; } }
.field label {
  display: block;
  font-size: 0.78rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 6px;
}
.field select, .field input[type="number"], .field input[type="text"] {
  width: 100%;
  background: var(--ink);
  border: 1px solid var(--ink-line);
  color: var(--paper);
  padding: 11px 12px;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 0.96rem;
}
.field select:focus, .field input:focus { border-color: var(--amber-dim); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: var(--amber);
  color: var(--ink);
  font-weight: 700;
  border: none;
  padding: 11px 20px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-family: var(--font-body);
  font-size: 0.95rem;
}
.btn:hover { background: #f0b752; text-decoration: none; }
.btn.secondary { background: transparent; color: var(--paper); border: 1px solid var(--ink-line); }
.btn.secondary:hover { border-color: var(--amber-dim); background: rgba(232,169,58,0.06); }

/* ---------------- Result page ---------------- */
.result-panel {
  background: var(--ink-raised);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  padding: 32px;
  margin: 28px 0;
}
.result-eyebrow { font-family: var(--font-mono); color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 16px; }
.result-headline { font-size: clamp(1.6rem, 3.4vw, 2.2rem); margin-bottom: 6px; }
.result-headline .eq { color: var(--amber); padding: 0 6px; }
.result-sub { color: var(--muted); font-size: 0.95rem; margin-bottom: 0; }

.meta-table { width: 100%; border-collapse: collapse; margin: 18px 0; }
.meta-table th, .meta-table td {
  text-align: left;
  padding: 10px 14px;
  border-bottom: 1px solid var(--ink-line);
  font-size: 0.92rem;
}
.meta-table th { color: var(--muted); font-weight: 600; width: 40%; }
.meta-table td { color: var(--paper); font-family: var(--font-mono); }

.crumbs { font-size: 0.85rem; color: var(--muted); margin-bottom: 20px; }
.crumbs a { color: var(--muted); }
.crumbs a:hover { color: var(--paper); }
.crumbs .sep { margin: 0 6px; opacity: 0.5; }

.related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin-top: 14px; }
@media (max-width: 640px) { .related-grid { grid-template-columns: 1fr; } }

.city-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; margin-bottom: 8px; }
@media (max-width: 900px) { .city-grid { grid-template-columns: repeat(3, 1fr); } }
@media (max-width: 560px) { .city-grid { grid-template-columns: repeat(2, 1fr); } }

.callout {
  border-left: 3px solid var(--amber-dim);
  background: rgba(232,169,58,0.06);
  padding: 14px 18px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.9rem;
  color: var(--muted);
  margin: 20px 0;
}

/* ---------------- Footer ---------------- */
.site-footer {
  border-top: 1px solid var(--ink-line);
  padding: 40px 0;
  margin-top: 40px;
  color: var(--muted);
  font-size: 0.88rem;
}
.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--paper); }
.footer-cols { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 24px; margin-bottom: 24px; }
@media (max-width: 760px) { .footer-cols { grid-template-columns: 1fr 1fr; } }
.footer-cols h4 { color: var(--paper); font-size: 0.82rem; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 10px; font-family: var(--font-body); font-weight: 700; }
.footer-cols ul { list-style: none; margin: 0; padding: 0; }
.footer-cols li { margin-bottom: 7px; }
.footer-bottom { border-top: 1px solid var(--ink-line); padding-top: 18px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }

/* ---------------- Misc / breadcrumbs / pagination ---------------- */
.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--ink);
  background: var(--teal);
  padding: 2px 8px;
  border-radius: 20px;
  letter-spacing: 0.04em;
}

.two-col { display: grid; grid-template-columns: 1.4fr 1fr; gap: 36px; align-items: start; }
@media (max-width: 860px) { .two-col { grid-template-columns: 1fr; } }

.admin-body { background: var(--ink); color: var(--paper); font-family: var(--font-body); }
.admin-card { background: var(--ink-raised); border: 1px solid var(--ink-line); border-radius: var(--radius); padding: 24px; }
table.admin-table { width: 100%; border-collapse: collapse; }
table.admin-table th, table.admin-table td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--ink-line); font-size: 0.88rem; }
table.admin-table th { color: var(--muted); }