:root {
  --ink: #171325;
  --ink-soft: #4d4763;
  --line: #e4e0ef;
  --bg: #ffffff;
  --bg-soft: #f7f5fb;
  --accent: #4b3ba8;
  --accent-soft: #ece9f9;
  --gold: #a3781f;
  --radius: 14px;
  --wrap: 1080px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

.wrap { width: 100%; max-width: var(--wrap); margin: 0 auto; padding: 0 20px; }

a { color: var(--accent); }

h1, h2, h3 { line-height: 1.25; margin: 0 0 .5em; }
h1 { font-size: clamp(1.9rem, 4.2vw, 2.7rem); letter-spacing: -.02em; }
h2 { font-size: clamp(1.35rem, 3vw, 1.8rem); margin-top: 2.2rem; }
h3 { font-size: 1.05rem; }

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

.site-head {
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 20;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(8px);
}
.site-head .wrap { display: flex; align-items: center; gap: 24px; min-height: 62px; flex-wrap: wrap; }
.brand { font-weight: 700; text-decoration: none; color: var(--ink); letter-spacing: -.01em; font-size: 1.1rem; }
.brand span { color: var(--accent); }
.site-nav { display: flex; gap: 18px; flex-wrap: wrap; margin-left: auto; }
.site-nav a { text-decoration: none; color: var(--ink-soft); font-size: .93rem; }
.site-nav a:hover { color: var(--accent); }

/* ---------- calculator ---------- */

.hero { padding: 40px 0 8px; }
.hero p.lede { font-size: 1.08rem; color: var(--ink-soft); max-width: 62ch; margin: 0 0 24px; }

.calc {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--bg-soft);
  padding: 22px;
}

.calc label { display: block; font-weight: 600; margin-bottom: 8px; }

.calc-row { display: flex; gap: 10px; }

#gem-input {
  flex: 1; min-width: 0;
  font-size: 1.25rem; padding: 14px 16px;
  border: 1px solid var(--line); border-radius: 10px;
  background: #fff; color: var(--ink);
  font-family: inherit;
}
#gem-input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: transparent; }

#gem-clear {
  border: 1px solid var(--line); background: #fff; color: var(--ink-soft);
  border-radius: 10px; padding: 0 16px; cursor: pointer; font-size: .95rem;
}
#gem-clear:hover { color: var(--accent); border-color: var(--accent); }

.examples { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; align-items: center; }
.examples b { font-weight: 600; font-size: .88rem; color: var(--ink-soft); margin-right: 4px; }
.examples button {
  border: 1px solid var(--line); background: #fff; color: var(--ink-soft);
  border-radius: 999px; padding: 5px 13px; cursor: pointer; font-size: .88rem;
  font-family: inherit;
}
.examples button:hover { border-color: var(--accent); color: var(--accent); }

#result-meta { margin: 18px 0 12px; font-size: .9rem; color: var(--ink-soft); }

.result-card {
  border: 1px solid var(--line); border-radius: 12px; background: #fff;
  margin-bottom: 10px; overflow: hidden;
}
.result-head {
  display: flex; align-items: center; gap: 16px; padding: 14px 16px; cursor: pointer;
}
.result-names h3 { margin: 0; }
.result-blurb { margin: 2px 0 0; font-size: .86rem; color: var(--ink-soft); }
.result-figure { margin-left: auto; text-align: right; flex-shrink: 0; }
.result-total { display: block; font-size: 1.7rem; font-weight: 700; color: var(--accent); line-height: 1.1; }
.result-root { display: block; font-size: .76rem; color: var(--ink-soft); }

.result-work { display: none; padding: 0 16px 14px; border-top: 1px solid var(--line); }
.result-card.is-open .result-work { display: block; }
.result-sum {
  margin: 12px 0 0; font-size: .9rem; color: var(--ink-soft);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  word-break: break-word;
}
.result-reduce { margin: 6px 0 0; font-size: .86rem; color: var(--gold); }

/* ---------- content ---------- */

.prose { max-width: 72ch; }
.prose p, .prose li { color: var(--ink-soft); }
.prose strong { color: var(--ink); }

section { padding: 6px 0; }

.grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); margin: 18px 0; }
.card { border: 1px solid var(--line); border-radius: 12px; padding: 16px; background: var(--bg-soft); }
.card h3 { margin-bottom: 4px; }
.card p { margin: 0; font-size: .92rem; color: var(--ink-soft); }
a.card { text-decoration: none; display: block; color: inherit; }
a.card:hover { border-color: var(--accent); }

.table-scroll { overflow-x: auto; margin: 16px 0; }
table { border-collapse: collapse; width: 100%; font-size: .92rem; }
th, td { border: 1px solid var(--line); padding: 8px 10px; text-align: left; }
th { background: var(--accent-soft); font-weight: 600; }

.faq details {
  border: 1px solid var(--line); border-radius: 10px; padding: 12px 16px; margin-bottom: 8px;
  background: var(--bg-soft);
}
.faq summary { cursor: pointer; font-weight: 600; }
.faq details p { margin: 10px 0 0; color: var(--ink-soft); }

.site-foot { border-top: 1px solid var(--line); margin-top: 48px; padding: 26px 0 40px; font-size: .9rem; color: var(--ink-soft); }
.site-foot a { color: var(--ink-soft); margin-right: 16px; }

/* ---------- Greek numeral converter ---------- */

.convert-pair { display: flex; align-items: flex-end; gap: 14px; }
.convert-field { flex: 1; min-width: 0; }
.convert-field label { display: block; font-weight: 600; margin-bottom: 8px; }
.convert-field input {
  width: 100%;
  font-size: 1.35rem; padding: 14px 16px;
  border: 1px solid var(--line); border-radius: 10px;
  background: #fff; color: var(--ink); font-family: inherit;
}
.convert-field input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: transparent; }
#num-arabic { font-variant-numeric: tabular-nums; }
.convert-swap { font-size: 1.3rem; color: var(--ink-soft); padding-bottom: 16px; flex-shrink: 0; }

.convert-work {
  margin: 16px 0 0; font-size: .9rem; color: var(--ink-soft);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  word-break: break-word; min-height: 1.2em;
}
.convert-note { margin: 6px 0 0; font-size: .86rem; color: var(--ink-soft); }
.convert-note.warn { color: var(--gold); }

@media (max-width: 560px) {
  .convert-pair { flex-direction: column; align-items: stretch; gap: 10px; }
  .convert-swap { align-self: center; padding: 0; transform: rotate(90deg); }
}

/* ---------- date calculator ---------- */

#date-input {
  flex: 1; min-width: 0;
  font-size: 1.15rem; padding: 13px 16px;
  border: 1px solid var(--line); border-radius: 10px;
  background: #fff; color: var(--ink); font-family: inherit;
}
#date-input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: transparent; }
#date-today {
  border: 1px solid var(--line); background: #fff; color: var(--ink-soft);
  border-radius: 10px; padding: 0 16px; cursor: pointer; font-size: .95rem; font-family: inherit;
}
#date-today:hover { color: var(--accent); border-color: var(--accent); }

.date-results { margin-top: 16px; }
.date-row {
  display: flex; align-items: baseline; gap: 16px;
  padding: 10px 0; border-top: 1px solid var(--line);
}
.date-row:first-child { border-top: 0; }
.date-label { flex: 0 0 40%; font-weight: 600; font-size: .92rem; }
.date-value { flex: 1; min-width: 0; }
.date-value b { font-size: 1.15rem; color: var(--accent); }
.date-value small {
  display: block; color: var(--ink-soft); font-size: .8rem; margin-top: 2px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  word-break: break-word;
}

@media (max-width: 560px) {
  .date-row { flex-direction: column; gap: 2px; }
  .date-label { flex: none; }
}

.byline { font-size: .85rem; color: var(--ink-soft); margin: 0 0 1.6rem; }
.byline time { color: inherit; }

/* Printing a value chart is a real use case, so make it a clean single page. */
@media print {
  .site-head, .site-foot, .calc, #result-meta, #results,
  .examples, .byline { display: none !important; }
  body { font-size: 11pt; color: #000; background: #fff; }
  .wrap { max-width: none; padding: 0; }
  .prose { max-width: none; }
  h1 { font-size: 20pt; margin-bottom: .2em; }
  h2 { font-size: 13pt; margin-top: 1.2em; page-break-after: avoid; }
  .hero { padding: 0; }
  .lede { font-size: 10pt; }
  a { color: #000; text-decoration: none; }
  /* Tables are the reason people print: keep them whole and readable. */
  .table-scroll { overflow: visible; }
  table { font-size: 10pt; page-break-inside: avoid; width: 100%; }
  th { background: #eee !important; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  th, td { padding: 3pt 5pt; }
  thead { display: table-header-group; }
  tr { page-break-inside: avoid; }
  .grid, .faq { page-break-inside: avoid; }
  .card { border: 1px solid #ccc; background: #fff; }
  .faq details { border: 0; background: #fff; padding: 0 0 6pt; }
  /* Force every answer open on paper, not just the ones the reader expanded. */
  .faq details > *:not(summary) { display: block !important; }
  @page { margin: 14mm; }
}

@media (max-width: 560px) {
  .calc { padding: 16px; }
  .result-head { flex-wrap: wrap; gap: 8px; }
  .result-figure { margin-left: 0; text-align: left; }
  .site-nav { gap: 12px; }
}