/* Patterns — page styles: the "Catalog of colorings" layout (light, big sans
   family headings, teal accent) with colour-group tabs, pattern subtabs and
   lazily rendered plate + details panes.  Shares the visual language of
   two-color-patterns.css. */

:root {
  color-scheme: light;
  /* Chrome tokens defer to style.css so these pages carry the same ink, rules
     and accent as catalog.html and gallery.html. Only the data colours below
     -- motif blue and orange, generator wine, seat -- are page-specific. */
  --pattern-ink: var(--ink);
  --pattern-muted: var(--muted);
  --pattern-rule: var(--rule);
  --pattern-soft: var(--code-bg);
  --pattern-accent: var(--accent);
  --pattern-blue: #0072b2;
  --pattern-orange: #e69f00;
  --pattern-wine: #7d2140;
  --pattern-seat: #c8452c;
}

/* Background, type scale and link colour all come from style.css now, so
   clicking in from catalog.html does not change the page under you. */
body.tcp {
  color: var(--pattern-ink);
}

main.tcp-page {
  width: min(100% - 2rem, 1060px);
  margin: 0 auto;
  padding: clamp(1.8rem, 3.5vw, 3.6rem) 1.2rem 8rem;
}

/* ---------------------------------------------------------- head */
.tcp-head h1 {
  max-width: 1050px;
  margin: 0;
  border: 0;
}
.catalog-subtitle {
  display: flex; flex-wrap: wrap; gap: 0.35rem 1rem;
  margin: 0.9rem 0 1rem;
  color: #44504c; font-size: clamp(0.92rem, 1.3vw, 1.08rem); line-height: 1.4;
}
.catalog-subtitle strong { color: var(--pattern-accent); font-weight: 720; }
.catalog-chips { margin: 0 0 0.6rem; }

/* ---------------------------------------------------------- directory */
.catalog-directory { margin: 1.4rem 0 2.5rem; }
.directory-grid {
  display: grid; grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.9rem 0.9rem; width: min(100%, 72rem); margin: 0 auto;
}
.directory-family {
  display: flex; flex-direction: column; min-width: 0;
  border: 1px solid var(--pattern-rule); border-radius: 0.7rem; overflow: hidden;
  color: inherit; background: #fff; text-decoration: none;
  position: relative;
  box-shadow: 0 1px 2px rgba(23, 27, 25, 0.05);
  transition: box-shadow 120ms ease, transform 120ms ease, border-color 120ms ease;
}
.directory-family:hover, .directory-family:focus-visible {
  color: inherit; border-color: #7fa79b;
  box-shadow: 0 8px 22px rgba(0, 118, 107, 0.16);
  transform: translateY(-2px);
  outline: none;
}
.directory-family img { display: block; width: 100%; height: auto; aspect-ratio: 4 / 3; object-fit: cover; background: #f8f7f1; border-bottom: 1px solid var(--pattern-rule); }
.directory-caption {
  display: flex; align-items: baseline; justify-content: space-between; gap: 0.4rem;
  padding: 0.42rem 0.6rem 0.48rem;
}
.directory-caption strong { font: 700 clamp(1rem, 1.5vw, 1.3rem)/1 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; letter-spacing: -0.02em; }
.directory-hm { color: var(--pattern-muted); font-size: 0.78rem; font-weight: 650; }
.directory-count {
  position: absolute; right: 0.5rem; top: 0.5rem; font: 650 0.7rem/1 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  color: #fff; background: var(--pattern-accent); border-radius: 999px; padding: 0.2rem 0.45rem;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.25);
}
.directory-credit { max-width: 72rem; margin: 0.55rem auto 0; color: var(--pattern-muted); font-size: 0.74rem; line-height: 1.4; }

/* ---------------------------------------------------------- introduction */
.tcp-intro { max-width: 62rem; margin: 0 auto 3.4rem; }
.tcp-intro p { font-size: 1.02rem; line-height: 1.6; color: #232926; }
.tcp-intro .tcp-note { font-size: 0.9rem; color: #44504c; }
.tcp-intro code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace; font-size: 0.9em; }
.sym { font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, "STIX Two Math", "Cambria Math", sans-serif; }
.census-wrap { overflow-x: auto; margin: 0.9rem 0; }
table.census { border-collapse: collapse; font-size: 0.9rem; }
table.census th, table.census td { padding: 0.42rem 0.85rem; border: 1px solid var(--pattern-rule); text-align: right; }
table.census th { background: var(--pattern-soft); color: var(--pattern-muted); font-weight: 650; }
table.census th.txt { text-align: left; }

/* signature typography */
.sig { font: 650 1.02rem/1.15 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; white-space: nowrap; }
.sig-big { font-size: 1.22rem; }
.sig sup { font-size: 0.6em; line-height: 0; vertical-align: 0.66em; }
.sig sup.sig-cyc { font-size: 0.52em; letter-spacing: 0.02em; }
.sig .sig-sym { font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, "STIX Two Math", "Cambria Math", sans-serif; }
.sig .seat-mark, .sig-annot .seat-mark {
  color: var(--pattern-seat);
  background: #fde8e2;
  border-radius: 0.2em;
  padding: 0 0.08em;
  box-shadow: 0 0 0 1px #f2c3b7;
}
.sig-annot .gen-letter { font-style: italic; color: var(--pattern-accent); font-weight: 700; font-size: 0.62em; line-height: 0; vertical-align: 0.66em; }
.seat-text { color: var(--pattern-seat); font-weight: 650; font-size: 0.92rem; }

/* ---------------------------------------------------------- atlas */
.pattern-atlas { display: grid; gap: 4.4rem; }
.wallpaper-family { min-width: 0; scroll-margin-top: 4.5rem; }
.family-header {
  display: grid; grid-template-columns: minmax(11rem, 0.32fr) minmax(0, 1fr);
  align-items: baseline; gap: 2rem; padding: 0 0 1.1rem; border-bottom: 1px solid var(--pattern-rule);
}
.family-header h2 { display: flex; align-items: baseline; gap: 0.75rem; margin: 0; border: 0; padding: 0; }
.family-orbifold { font: 700 clamp(2.6rem, 5vw, 5rem)/0.9 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; letter-spacing: -0.055em; }
.family-hm { color: var(--pattern-muted); font-size: 0.92rem; font-weight: 650; }
.family-header p { margin: 0; color: #3f4a46; font-size: 1.02rem; }

/* colour-group tabs */
.colour-group-tabs { display: flex; flex-wrap: wrap; align-items: stretch; gap: 0.45rem; padding: 0.9rem 0 0; }
.tab-k-divider {
  align-self: center; flex: 0 0 auto; margin-right: 0.15rem; padding: 0.2rem 0.5rem;
  color: var(--pattern-accent); background: #e7f3ef; border-radius: 999px;
  font: 700 0.68rem/1.2 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; letter-spacing: 0.03em; text-transform: uppercase;
}
.tab-k-divider:not(:first-child) { margin-left: 0.6rem; }
.colour-group-tab {
  display: grid; flex: 0 0 auto; min-width: 7.6rem; padding: 0.5rem 0.7rem 0.5rem;
  border: 1px solid var(--pattern-rule); border-bottom-color: #aebbb5; border-radius: 0.6rem;
  color: #4d5955; background: var(--pattern-soft); text-decoration: none;
}
.colour-group-tab:hover, .colour-group-tab:focus-visible { border-color: #83978e; color: var(--pattern-ink); background: #fff; outline: none; }
.colour-group-tab[aria-selected="true"] {
  background: #fff; color: var(--pattern-ink); border-color: #5d8479;
  box-shadow: inset 0 3px 0 var(--pattern-accent);
}
.colour-group-tab.is-trivial { opacity: 0.55; filter: grayscale(0.6); }
.colour-group-tab.is-trivial[aria-selected="true"] { opacity: 0.9; filter: none; }
.tab-name { min-height: 1.35rem; }
.tab-name .sig { font-size: 0.95rem; }
.tab-palette { display: flex; width: 100%; height: 0.4rem; margin: 0.4rem 0 0.28rem; overflow: hidden; border: 1px solid #aab5b0; border-radius: 999px; }
.tab-palette span { flex: 1 1 0; background: var(--swatch); }
.tab-sub { font-size: 0.7rem; color: var(--pattern-muted); white-space: nowrap; }

/* colour-group panel (lazy) */
.colour-group-panel { margin-top: 1.1rem; border: 1px solid var(--pattern-rule); border-radius: 0.6rem; background: #fff; scroll-margin-top: 4.5rem; }
.band-header { padding: 0.85rem clamp(1rem, 2vw, 1.6rem) 0.65rem; border-bottom: 1px solid var(--pattern-rule); background: var(--pattern-soft); border-radius: 0.6rem 0.6rem 0 0; }
.band-header h3 { margin: 0; font: 700 1.3rem/1.2 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; display: flex; gap: 0.9rem; align-items: baseline; flex-wrap: wrap; }
.band-type { font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, "STIX Two Math", "Cambria Math", sans-serif; }
.band-meta { margin: 0.25rem 0 0; font-size: 0.86rem; color: #3f4a46; }

/* pattern subtabs */
.pattern-tabs {
  display: flex; flex-wrap: wrap; gap: 0.4rem;
  padding: 0.7rem clamp(1rem, 2vw, 1.6rem) 0.65rem; border-bottom: 1px solid var(--pattern-rule);
}
.pattern-tab {
  display: inline-flex; flex-direction: column; gap: 0.1rem; padding: 0.35rem 0.65rem;
  border: 1px solid var(--pattern-rule); border-radius: 0.5rem;
  background: var(--pattern-soft); color: #4d5955; text-decoration: none;
}
.pattern-tab:hover, .pattern-tab:focus-visible { border-color: #83978e; color: var(--pattern-ink); background: #fff; outline: none; }
.pattern-tab[aria-selected="true"] { background: #fff; color: var(--pattern-ink); border-color: #5d8479; box-shadow: inset 0 2px 0 var(--pattern-accent); }
.ptab-label { font: 700 0.9rem/1.15 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; }
.ptab-seat { font-size: 0.66rem; color: var(--pattern-muted); max-width: 12rem; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* pane */
.pattern-pane { scroll-margin-top: 4.5rem; }
.pane-body {
  display: grid; grid-template-columns: minmax(0, 1.22fr) minmax(22rem, 0.78fr);
  gap: clamp(1rem, 2vw, 2rem); padding: clamp(0.8rem, 1.6vw, 1.3rem) clamp(1rem, 2vw, 1.6rem) clamp(1rem, 2vw, 1.6rem);
}
.pattern-plate { margin: 0; min-width: 0; }
.pattern-plate svg { display: block; width: 100%; height: auto; aspect-ratio: 12 / 7; border: 1px solid #cdd8d3; background: #f8f7f1; }
.pattern-plate figcaption { font-size: 0.74rem; color: var(--pattern-muted); margin-top: 0.35rem; }
.cap-keep { color: var(--pattern-wine); font-weight: 650; }
.cap-swap { color: var(--pattern-wine); font-weight: 650; }
.cap-fix { color: var(--pattern-seat); font-weight: 650; }
.pattern-details { min-width: 0; align-self: start; }

.plate-bg { fill: #f8f7f1; }
.motif-fill { stroke: #26322e; stroke-width: 1.2px; vector-effect: non-scaling-stroke; }
.motif-letter { fill: #fffaf1; stroke: #26322e; stroke-width: 0.6; paint-order: stroke fill; font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; font-weight: 800; }
.generator-overlay { pointer-events: none; }
.gen-halo { fill: none; stroke: rgba(255, 253, 247, 0.9); stroke-width: 6px; stroke-linecap: round; vector-effect: non-scaling-stroke; }
.gen-mirror { fill: none; stroke: var(--pattern-wine); stroke-width: 2.1px; vector-effect: non-scaling-stroke; }
.gen-glide { fill: none; stroke: var(--pattern-wine); stroke-width: 1.8px;
  stroke-dasharray: 9 6; vector-effect: non-scaling-stroke; }
.gen-glide-vec { fill: none; stroke: var(--pattern-wine); stroke-width: 2.6px;
  stroke-linecap: round; stroke-linejoin: round; vector-effect: non-scaling-stroke; }
.gen-glide-halo { fill: none; stroke: rgba(255, 253, 247, 0.92); stroke-width: 5.4px;
  stroke-linecap: round; stroke-linejoin: round; vector-effect: non-scaling-stroke; }
.gen-arc { fill: none; stroke: var(--pattern-wine); stroke-width: 2.1px; stroke-linecap: round; vector-effect: non-scaling-stroke; }
.gen-arrow { fill: var(--pattern-wine); stroke: rgba(255, 253, 247, 0.9); stroke-width: 1.2px; paint-order: stroke fill; }
.gen-centre { fill: var(--pattern-wine); stroke: #fffdf7; stroke-width: 2.3px; }
.gen.moves .gen-centre { fill: #fff; stroke: var(--pattern-wine); stroke-width: 2.4px; }
.gen-label { fill: #5f1731; stroke: rgba(255, 253, 247, 0.96); stroke-width: 5px; paint-order: stroke fill; font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, "STIX Two Math", "Cambria Math", sans-serif; font-size: 22px; font-weight: 800; }
/* the generator that fixes the marked motif: seat red */
.gen.fixes .gen-mirror, .gen.fixes .gen-glide, .gen.fixes .gen-arc { stroke: var(--pattern-seat); }
.gen.fixes .gen-glide-vec { stroke: var(--pattern-seat); }
.gen.fixes .gen-arrow { fill: var(--pattern-seat); }
.gen.fixes .gen-centre { fill: var(--pattern-seat); }
.gen.fixes.moves .gen-centre { fill: #fff; stroke: var(--pattern-seat); }
.gen.fixes .gen-label { fill: var(--pattern-seat); }
.seat-ring { fill: none; stroke: var(--pattern-seat); stroke-width: 2.4px; stroke-dasharray: 4 3; }

/* details */
.pattern-data { width: 100%; border-collapse: collapse; font-size: clamp(0.84rem, 1vw, 0.95rem); }
.pattern-data th, .pattern-data td { padding: 0.55rem 0.6rem; border-bottom: 1px solid var(--pattern-rule); text-align: left; vertical-align: top; }
.pattern-data th { width: 34%; color: var(--pattern-muted); font-weight: 650; }
.pattern-data tr:last-child th, .pattern-data tr:last-child td { border-bottom: 0; }
.source-value-link { display: inline-flex; align-items: baseline; gap: 0.32rem; color: var(--pattern-ink); font: 650 1.05rem/1.15 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; text-decoration-color: #7f9c92; }
.source-value-link:hover, .source-value-link:focus-visible { color: var(--pattern-accent); }
.source-math-symbol { font: 650 1.05rem/1.15 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; }
.source-link-mark { color: var(--pattern-accent); font: 650 0.72rem/1 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; }
.syn-note { color: var(--pattern-muted); font-size: 0.76rem; }
.beyond-note { color: var(--pattern-seat); font-weight: 650; font-size: 0.78rem; }

.group-presentation { margin: 1.1rem 0 0; }
.presentation-heading { display: flex; align-items: center; justify-content: space-between; gap: 0.75rem; margin: 0 0 0.28rem; }
.group-presentation h4 { margin: 0; color: var(--pattern-ink); font-size: 0.82rem; font-weight: 700; }
.action-palette { display: flex; align-items: center; gap: 0.3rem; color: var(--pattern-muted); font: 650 0.72rem/1 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; white-space: nowrap; }
.action-colour { display: inline-grid; width: 1.45rem; height: 1.45rem; place-items: center; border: 1px solid #53625c; border-radius: 0.2rem; color: #fff; background: var(--swatch); font: 700 0.72rem/1 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; }
.action-colour:nth-child(2), .action-colour:nth-child(6) { color: #17201d; }
.group-presentation table { width: 100%; border-collapse: collapse; border-block: 1px solid var(--pattern-rule); font-size: 0.8rem; }
.group-presentation th, .group-presentation td { padding: 0.38rem 0.45rem; border-bottom: 1px solid var(--pattern-rule); text-align: left; vertical-align: top; }
.group-presentation th { color: var(--pattern-ink); font-weight: 500; }
.group-presentation tbody tr:last-child th, .group-presentation tbody tr:last-child td { border-bottom: 0; }
.generator-key { display: inline-block; min-width: 1.45rem; margin-right: 0.36rem; color: var(--pattern-accent); font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; font-weight: 700; line-height: 1; }
.generator-geometry { color: var(--pattern-muted); line-height: 1.25; }
.presentation-permutation { color: var(--pattern-ink); font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; font-weight: 700; white-space: nowrap; }
.presentation-identity { color: #9aa8a2; }
.seat-cell { width: 8rem; white-space: nowrap; }
.seat-flag { color: var(--pattern-seat); font-weight: 650; }
.presentation-relations { display: flex; gap: 0.6rem; margin: 0.5rem 0 0; color: var(--pattern-ink); font: 0.82rem/1.45 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; }
.presentation-relations strong { flex: 0 0 auto; color: var(--pattern-muted); font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; font-size: 0.7rem; letter-spacing: 0.025em; }
.presentation-relations span { min-width: 0; overflow-wrap: anywhere; }
.invariant-text { margin: 0.55rem 0 0; font-size: 0.82rem; line-height: 1.5; color: #3a2f2c; }

.book-evidence-link { color: #315d55; }
.lightbox { position: fixed; inset: 0; z-index: 200; background: rgba(20, 24, 22, 0.78); display: grid; place-items: center; padding: 1.5rem; }
.lightbox[hidden] { display: none; }
.lightbox-inner { background: #fff; border-radius: 0.6rem; padding: 0.8rem 0.9rem 0.6rem; max-width: min(96vw, 1100px); max-height: 92vh; overflow: auto; box-shadow: 0 20px 60px rgba(0,0,0,0.4); }
.lightbox-inner img { display: block; max-width: 100%; max-height: 78vh; margin: 0 auto; }
.lightbox-caption { margin: 0.5rem 0 0; font-size: 0.86rem; color: var(--pattern-muted); }
.lightbox-close { float: right; margin-top: 0.3rem; border: 1px solid var(--pattern-rule); background: var(--pattern-soft); border-radius: 0.35rem; padding: 0.25rem 0.6rem; font: 650 0.8rem/1 ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif; cursor: pointer; }
.noscript-note { padding: 1rem; border: 1px solid var(--pattern-rule); }

@media (max-width: 1050px) { .pane-body { grid-template-columns: 1fr; } }
@media (max-width: 760px) {
  main.tcp-page { width: min(100% - 1rem, 1060px); }
  .directory-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .family-header { grid-template-columns: 1fr; gap: 0.75rem; }
  .colour-group-tab { flex: 1 1 8rem; max-width: 100%; min-width: 0; }
  .tab-name { overflow: hidden; }
  .family-header p { overflow-wrap: anywhere; }
}
@media (max-width: 420px) {
  .directory-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
body.tcp header.site nav a { color: var(--pattern-muted); }
body.tcp footer.site { color: var(--pattern-muted); }

/* Line style is the geometry — solid mirror, dashed glide, as in International
   Tables. The glide's half arrow gives its direction and its half-cell length.
   Colour cycling used to be shown by dashing, which made a colour-swapping
   mirror look like a glide; it now has its own channel, these chips. */
.gen-cycle-chip { stroke: rgba(255, 253, 247, 0.95); stroke-width: 1px; paint-order: stroke fill; }
.gen-cycle-loop { fill: none; stroke: var(--pattern-wine); stroke-width: 1.1px; opacity: 0.75; }