:root {
  --ink: #23282e;
  --ink-soft: #55606c;
  --paper: #f7f5f0;
  --panel: #ffffff;
  --navy: #2f5a78;
  --navy-deep: #1f3d54;
  --amber: #f2b632;
  --amber-soft: #fdeec9;
  --green: #1c6e3c;
  --green-soft: #e3f1e8;
  --red: #b3261e;
  --red-soft: #fbeeed;
  --line: #ddd6ca;
  --radius: 10px;
  color-scheme: light;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Segoe UI", -apple-system, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5;
}

main { max-width: 64rem; margin: 0 auto; padding: 1.5rem 1rem 3rem; }

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

.site-header { text-align: center; margin-bottom: 1.5rem; }

.site-header h1 {
  font-size: 2rem;
  margin: 0.25rem 0;
  color: var(--navy-deep);
  letter-spacing: -0.5px;
}

.tagline { max-width: 42rem; margin: 0 auto 0.5rem; color: var(--ink-soft); }

.disclaimer {
  font-size: 0.8rem;
  color: var(--ink-soft);
  max-width: 42rem;
  margin: 0 auto;
  opacity: 0.85;
}

/* ---------- layout & panels ---------- */

.layout {
  display: grid;
  grid-template-columns: minmax(17rem, 22rem) 1fr;
  gap: 1rem;
  align-items: start;
}

@media (max-width: 54rem) {
  .layout { grid-template-columns: 1fr; }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.1rem 1.2rem 1.3rem;
  box-shadow: 0 1px 3px rgba(35, 40, 46, 0.06);
}

.panel h2 {
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--navy);
  margin: 0 0 1rem;
  border-bottom: 2px solid var(--amber);
  display: inline-block;
  padding-bottom: 0.25rem;
}

/* ---------- form fields ---------- */

.field { margin-bottom: 0.9rem; }
.field.small { margin-bottom: 0; flex: 1; }

.field-label {
  display: block;
  font-weight: 600;
  font-size: 0.85rem;
  margin-bottom: 0.25rem;
  color: var(--navy-deep);
}

input[type="number"], select {
  width: 100%;
  padding: 0.5rem 0.6rem;
  font: inherit;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fcfbf8;
  color: var(--ink);
}

input[type="number"]:focus, select:focus {
  outline: 2px solid var(--amber);
  outline-offset: 1px;
  border-color: var(--navy);
}

.hint { font-size: 0.75rem; color: var(--ink-soft); margin: 0.3rem 0 0; }

/* format-conditional visibility */
.print-only { display: none; }
.plan-panel[data-format="paperback"] .print-only,
.plan-panel[data-format="hardcover"] .print-only { display: block; }

.ebook-only { display: none; }
.plan-panel[data-format="ebook"] .ebook-only { display: block; }

.plan-panel[data-format="hardcover"] #distribution-field select { opacity: 0.55; }
.plan-panel[data-format="hardcover"] .hint-for-expanded { color: var(--ink-soft); }

/* ---------- presets ---------- */

.presets { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 1rem; }

.preset {
  font: inherit;
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.45rem 0.7rem;
  border: 1px solid var(--navy);
  background: #eef4f8;
  color: var(--navy-deep);
  border-radius: 999px;
  cursor: pointer;
}

.preset:hover, .preset:focus-visible { background: var(--navy); color: #fff; }

/* ---------- slider row & spotlight ---------- */

.range-row {
  display: flex;
  gap: 0.7rem;
  margin: 0 0 0.9rem;
  flex-wrap: wrap;
}

.slider-row { margin-bottom: 1rem; }

#ladderSlider { width: 100%; accent-color: var(--navy); height: 1.6rem; }

.slider-price {
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--navy-deep);
  background: var(--amber-soft);
  border-radius: 8px;
  padding: 0.05rem 0.6rem;
}

.spotlight {
  border: 2px solid var(--navy);
  border-radius: var(--radius);
  background: linear-gradient(135deg, #eef4f8 0%, #fdf8ee 100%);
  padding: 0.9rem 1rem;
  margin-bottom: 1rem;
}

.spot-price {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  flex-wrap: wrap;
  margin-bottom: 0.5rem;
}

.spot-value { font-size: 1.7rem; font-weight: 800; color: var(--navy-deep); }

.spot-tier {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--navy-deep);
  background: var(--amber);
  border-radius: 999px;
  padding: 0.15rem 0.6rem;
}

.spot-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.5rem;
}

.spot-metric {
  background: #ffffffcc;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.5rem 0.6rem;
}

.spot-metric dt {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--ink-soft);
}

.spot-metric dd { margin: 0.2rem 0 0; font-size: 1.25rem; font-weight: 700; color: var(--navy-deep); }

.spot-metric dd.negative { color: var(--red); }
.spot-metric dd.muted { color: var(--ink-soft); font-weight: 500; }

.spot-note { min-height: 1.2em; margin: 0.6rem 0 0; font-size: 0.85rem; font-weight: 600; }
.spot-note.warn { color: var(--red); }
.spot-note.good { color: var(--green); }

/* ---------- ladder table ---------- */

.table-wrap { overflow-x: auto; }

table { border-collapse: collapse; width: 100%; font-size: 0.88rem; }

caption {
  caption-side: top;
  text-align: left;
  font-size: 0.78rem;
  color: var(--ink-soft);
  padding-bottom: 0.4rem;
}

th, td { text-align: left; padding: 0.45rem 0.55rem; border-bottom: 1px solid var(--line); }

thead th {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--ink-soft);
  border-bottom: 2px solid var(--navy);
}

.num { text-align: right; font-variant-numeric: tabular-nums; }

tbody tr { cursor: pointer; transition: background 0.12s ease; }

tbody tr:hover { background: #f3efe6; }

tbody tr.selected {
  background: var(--amber-soft);
  box-shadow: inset 3px 0 0 var(--navy);
}

tbody tr.unprofitable .royalty-cell { color: var(--red); font-weight: 700; }

tbody tr.royalty-positive .royalty-cell { color: var(--green); font-weight: 600; }

.tier-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  border-radius: 4px;
  padding: 0.05rem 0.35rem;
  background: #eef4f8;
  color: var(--navy-deep);
}

.tier-badge.off { background: #f1ece2; color: var(--ink-soft); }
.tier-badge.expand { background: var(--amber-soft); color: #7a5a10; }

.muted { color: var(--ink-soft); }

/* ---------- explain section ---------- */

.explain { margin-top: 1rem; }

.explain-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 1rem;
}

.explain h3 { margin: 0 0 0.3rem; font-size: 0.95rem; color: var(--navy-deep); }
.explain p { margin: 0.3rem 0; font-size: 0.88rem; color: var(--ink-soft); }

.formula {
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  font-size: 0.8rem;
  background: #f3efe6;
  border-left: 3px solid var(--amber);
  border-radius: 4px;
  padding: 0.45rem 0.6rem;
  color: var(--ink);
}

.tier-tag {
  display: inline-block;
  font-family: "Segoe UI", Arial, sans-serif;
  font-size: 0.65rem;
  font-weight: 700;
  background: var(--amber);
  border-radius: 3px;
  padding: 0 0.3rem;
  margin-left: 0.2rem;
}

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

.site-footer {
  margin-top: 1.5rem;
  text-align: center;
  font-size: 0.82rem;
  color: var(--ink-soft);
}

.footer-links { display: inline; }

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}

@media print {
  body { background: #fff; }
  .presets, .slider-row, .hint { display: none; }
}