:root {
  color-scheme: light;
  --bg: oklch(0.955 0.008 76);
  --panel: oklch(0.985 0.006 82);
  --panel-2: oklch(0.925 0.009 88);
  --ink: oklch(0.225 0.015 245);
  --muted: oklch(0.48 0.018 245);
  --faint: oklch(0.71 0.012 245);
  --line: oklch(0.84 0.013 92);
  --accent: oklch(0.58 0.19 34);
  --accent-ink: oklch(0.985 0.006 82);
  --teal: oklch(0.58 0.09 190);
  --amber: oklch(0.72 0.13 82);
  --green: oklch(0.58 0.12 145);
  --shadow: 0 18px 60px oklch(0.28 0.01 245 / 0.13);
  --radius: 8px;
  --rail: 286px;
  --inspector: 372px;
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-width: 320px;
  overflow-x: hidden;
  background:
    linear-gradient(90deg, oklch(0.94 0.012 82), transparent 28%),
    radial-gradient(circle at 76% 12%, oklch(0.78 0.075 190 / 0.2), transparent 32rem),
    var(--bg);
  color: var(--ink);
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.app-shell {
  min-height: 100vh;
  display: grid;
  grid-template-columns: minmax(240px, var(--rail)) minmax(0, 1fr) minmax(320px, var(--inspector));
  max-width: 100vw;
}

.rail,
.inspector {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: auto;
  background: color-mix(in oklch, var(--panel) 88%, var(--bg));
}

.rail {
  border-right: 1px solid var(--line);
  padding: 22px 18px;
}

.brand {
  display: flex;
  gap: 12px;
  align-items: center;
  padding-bottom: 24px;
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background:
    radial-gradient(circle at 34% 36%, var(--panel) 0 18%, transparent 19%),
    conic-gradient(from 30deg, var(--accent), var(--teal), var(--amber), var(--accent));
  box-shadow: inset 0 0 0 2px oklch(0.99 0.004 82), 0 8px 24px oklch(0.33 0.02 245 / 0.16);
}

.brand-name,
.brand-sub,
.group-title,
.field-label,
.eyeless {
  margin: 0;
}

.brand-name {
  font-size: 14px;
  font-weight: 760;
  letter-spacing: 0;
}

.brand-sub,
.eyeless {
  color: var(--muted);
  font-size: 12px;
}

.field-label,
.group-title {
  display: block;
  color: var(--muted);
  font-size: 12px;
  font-weight: 720;
  margin-bottom: 8px;
}

.search-row {
  display: grid;
  grid-template-columns: 1fr 34px;
  gap: 6px;
  margin-bottom: 22px;
}

input[type="search"] {
  width: 100%;
  min-height: 36px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 11px;
  background: var(--panel);
  color: var(--ink);
  outline: none;
}

input[type="search"]:focus {
  border-color: color-mix(in oklch, var(--accent) 70%, var(--line));
  box-shadow: 0 0 0 3px oklch(0.58 0.19 34 / 0.13);
}

#clearSearch,
.top-actions button,
.chip,
.option-row,
.rule-toggle {
  min-height: 34px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  color: var(--ink);
}

.control-group {
  margin-top: 21px;
}

.chip-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 7px;
}

.chip,
.option-row,
.rule-toggle {
  font-size: 12px;
  font-weight: 680;
}

.chip.active,
.option-row.active,
.rule-toggle.active {
  color: var(--accent-ink);
  background: var(--accent);
  border-color: var(--accent);
}

.stacked-options,
.rule-list {
  display: grid;
  gap: 8px;
}

.option-row,
.rule-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 0 10px;
  text-align: left;
}

.option-count {
  color: inherit;
  opacity: 0.72;
}

.workspace {
  min-width: 0;
  padding: 22px 24px 28px;
  overflow: hidden;
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: flex-start;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 6px;
  font-size: 30px;
  line-height: 1.08;
  letter-spacing: 0;
}

.topbar p,
.floor-heading p,
.note {
  max-width: 68ch;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.55;
}

.top-actions {
  display: flex;
  gap: 9px;
  flex-wrap: wrap;
}

.top-actions button {
  padding: 0 13px;
  font-size: 13px;
  font-weight: 720;
}

.top-actions .primary {
  background: var(--ink);
  color: var(--panel);
  border-color: var(--ink);
}

.summary-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 22px 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--line);
}

.summary-strip > div {
  min-height: 72px;
  display: grid;
  align-content: center;
  padding: 14px 16px;
  background: color-mix(in oklch, var(--panel) 92%, var(--bg));
}

.summary-value {
  font-size: 24px;
  font-weight: 780;
  line-height: 1;
}

.summary-label {
  color: var(--muted);
  font-size: 12px;
  margin-top: 6px;
}

.table-stage {
  overflow: auto;
  max-height: calc(100vh - 255px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(var(--panel), var(--panel)) padding-box,
    linear-gradient(135deg, oklch(0.82 0.08 34), oklch(0.78 0.06 190)) border-box;
  box-shadow: var(--shadow);
}

.periodic-table {
  min-width: 0;
  display: grid;
  grid-template-columns: repeat(7, minmax(116px, 1fr));
  gap: 1px;
  background: var(--line);
}

.knot-column {
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--line);
}

.column-label {
  position: sticky;
  top: 0;
  z-index: 1;
  min-height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--panel-2);
  color: var(--muted);
  font-size: 12px;
  font-weight: 760;
}

.knot-cell {
  min-height: 156px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 8px;
  padding: 11px;
  border: 0;
  border-radius: 0;
  background: var(--panel);
  color: var(--ink);
  text-align: left;
}

.knot-cell:hover,
.knot-cell:focus-visible {
  position: relative;
  z-index: 2;
  outline: 2px solid color-mix(in oklch, var(--accent) 70%, var(--panel));
  outline-offset: -2px;
}

.knot-cell.selected {
  background: oklch(0.96 0.026 42);
  box-shadow: inset 0 0 0 2px var(--accent);
}

.knot-cell.hidden {
  display: none;
}

.cell-header,
.cell-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.knot-id {
  font-size: 14px;
  font-weight: 780;
}

.crossing-badge,
.family,
.det {
  color: var(--muted);
  font-size: 11px;
  font-weight: 660;
}

.mini-diagram svg {
  width: 100%;
  height: 86px;
  display: block;
}

.mini-diagram {
  display: grid;
  place-items: center;
  min-height: 86px;
}

.mini-diagram img {
  max-width: 86px;
  max-height: 86px;
  width: auto;
  height: auto;
  object-fit: contain;
  filter: drop-shadow(0 4px 4px oklch(0.25 0.01 245 / 0.18));
}

.proof-floor {
  margin-top: 24px;
}

.floor-heading {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: baseline;
}

.floor-heading h2,
.inspector h2 {
  margin-bottom: 4px;
  font-size: 19px;
}

.timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.timeline li {
  min-height: 86px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 12px;
  background: color-mix(in oklch, var(--panel) 92%, var(--bg));
}

.timeline strong {
  display: block;
  font-size: 13px;
}

.timeline span {
  display: block;
  margin-top: 6px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.4;
}

.inspector {
  border-left: 1px solid var(--line);
  padding: 22px 18px;
}

.inspector-head {
  margin-bottom: 16px;
}

#selectedTitle {
  color: var(--muted);
  font-size: 14px;
}

.viewer {
  aspect-ratio: 4 / 3;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background:
    radial-gradient(circle at 50% 46%, oklch(0.985 0.006 82), oklch(0.9 0.012 88)),
    var(--panel);
}

#knotImage {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: contain;
  padding: 28px;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin: 15px 0 18px;
}

.tag-row span {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 5px 8px;
  background: var(--panel);
  color: var(--muted);
  font-size: 11px;
  font-weight: 720;
}

.inspector-section {
  border-top: 1px solid var(--line);
  padding-top: 16px;
  margin-top: 16px;
}

.inspector-section h3 {
  margin-bottom: 10px;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.invariant-list {
  display: grid;
  gap: 8px;
  margin: 0;
}

.invariant-list div {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  border-bottom: 1px solid color-mix(in oklch, var(--line) 70%, transparent);
  padding-bottom: 7px;
}

.invariant-list dt {
  color: var(--muted);
  font-size: 12px;
}

.invariant-list dd {
  margin: 0;
  font-size: 12px;
  font-weight: 720;
  text-align: right;
}

.check-list {
  display: grid;
  gap: 8px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.check-list li {
  display: flex;
  gap: 8px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.35;
}

.check-list li::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-top: 4px;
  flex: 0 0 auto;
  background: var(--green);
}

@media (max-width: 1180px) {
  .app-shell {
    grid-template-columns: minmax(0, 1fr) minmax(318px, 38vw);
  }

  .rail {
    grid-column: 1 / -1;
    position: static;
    height: auto;
    display: grid;
    grid-template-columns: minmax(170px, 0.85fr) minmax(220px, 1fr) repeat(3, minmax(160px, 1fr));
    gap: 14px;
    align-items: start;
    border-right: 0;
    border-bottom: 1px solid var(--line);
    padding: 14px;
  }

  .brand {
    padding-bottom: 0;
  }

  .rail .field-label,
  .rail .search-row,
  .rail .control-group {
    margin: 0;
  }

  .chip-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .inspector {
    grid-column: auto;
    position: sticky;
    height: 100vh;
    border-left: 1px solid var(--line);
    border-top: 0;
  }

  .workspace {
    padding: 18px 18px 24px;
  }
}

@media (max-width: 980px) {
  .app-shell {
    display: block;
  }

  .rail,
  .inspector {
    position: static;
    height: auto;
  }

  .rail {
    display: block;
  }

  .rail .search-row {
    margin-bottom: 18px;
  }

  .rail .control-group {
    margin-top: 18px;
  }

  .inspector {
    border-left: 0;
    border-top: 1px solid var(--line);
  }
}

@media (max-width: 780px) {
  .workspace {
    padding: 18px 14px 24px;
  }

  .topbar,
  .floor-heading {
    display: grid;
  }

  .summary-strip,
  .timeline {
    grid-template-columns: 1fr;
  }

  .table-stage {
    max-height: 620px;
  }

  h1 {
    font-size: 24px;
  }
}