/* ---------------------------------------------------------------- token -- */

:root {
  --ground: #f0f1ef;
  --surface: #ffffff;
  --surface-2: #f6f6f4;
  --surface-3: #e9eae6;
  --line: #dcdcd6;
  --line-strong: #c3c4bd;
  --ink: #14171a;
  --ink-2: #4c5259;
  --ink-3: #7e858c;
  --accent: #16457a;
  --accent-ink: #ffffff;
  --accent-soft: #e4ecf6;
  --true: #1d6b4f;
  --true-soft: #dfeee6;
  --false: #5b6470;
  --false-soft: #e8eaec;
  --warn: #a33325;
  --warn-soft: #f7e6e2;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --r: 5px;
}

* {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font: 15px/1.55 var(--sans);
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3 {
  margin: 0;
  letter-spacing: -0.018em;
  line-height: 1.15;
  font-weight: 650;
}

p {
  margin: 0;
}

code {
  font: 0.9em/1.4 var(--mono);
  background: var(--surface-3);
  padding: 1px 5px;
  border-radius: 3px;
}

.shell {
  max-width: 1340px;
  margin: 0 auto;
  padding: 30px 26px 70px;
}

/* ------------------------------------------------------------------ head -- */

.head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  grid-template-areas: "main meta" "act act";
  gap: 18px 28px;
  align-items: end;
  padding-bottom: 22px;
}

.head__main {
  grid-area: main;
}

h1 {
  font-size: clamp(26px, 3.1vw, 40px);
  max-width: 22ch;
  letter-spacing: -0.03em;
}

.head__sub {
  margin-top: 10px;
  max-width: 62ch;
  color: var(--ink-2);
  font-size: 14.5px;
}

.kbmeta {
  grid-area: meta;
  display: grid;
  grid-auto-flow: column;
  gap: 26px;
  margin: 0;
  padding-bottom: 3px;
}

.kbmeta div {
  display: grid;
  gap: 2px;
}

.kbmeta dt {
  font-size: 11.5px;
  color: var(--ink-3);
}

.kbmeta dd {
  margin: 0;
  font: 600 19px/1.2 var(--sans);
  font-variant-numeric: tabular-nums;
}

.kbmeta dd.is-bad {
  color: var(--warn);
}

.kbmeta dd.is-ok {
  color: var(--true);
}

.head__act {
  grid-area: act;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

/* ---------------------------------------------------------------- button -- */

.btn {
  appearance: none;
  border: 1px solid var(--line-strong);
  background: var(--surface);
  color: var(--ink);
  font: 500 13.5px/1 var(--sans);
  padding: 9px 14px;
  border-radius: 4px;
  cursor: pointer;
  transition: background 0.16s ease, border-color 0.16s ease, color 0.16s ease;
}

.btn:hover {
  background: var(--surface-2);
  border-color: var(--ink-3);
}

.btn:active {
  transform: translateY(1px);
}

.btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.btn--primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
  padding: 11px 16px;
}

.btn--primary:hover {
  background: #10365f;
  border-color: #10365f;
}

.btn--wide {
  width: 100%;
  margin-top: 4px;
}

.btn--sm {
  padding: 7px 11px;
  font-size: 12.5px;
}

.btn--danger {
  border-color: #d9a096;
  color: var(--warn);
}

.btn--danger:hover {
  background: var(--warn-soft);
  border-color: var(--warn);
}

.btn[disabled] {
  opacity: 0.45;
  cursor: not-allowed;
}

/* ----------------------------------------------------------------- board -- */

.board {
  display: grid;
  grid-template-columns: 372px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r);
  padding: 20px 20px 22px;
}

.card h2 {
  font-size: 17px;
  margin-bottom: 14px;
}

.card__head {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 18px;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.card--tree .card__head h2,
.card--log .card__head h2 {
  margin-bottom: 0;
}

/* ----------------------------------------------------------------- field -- */

.fields {
  display: grid;
  gap: 13px;
}

.field {
  display: grid;
  gap: 4px;
}

.field__label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
  font-size: 12.5px;
  color: var(--ink-2);
  font-weight: 500;
}

.field__hint {
  font-size: 11px;
  color: var(--ink-3);
  font-weight: 400;
}

.field__box {
  position: relative;
  display: flex;
  align-items: center;
}

.field input,
.field select {
  width: 100%;
  appearance: none;
  border: 1px solid var(--line-strong);
  border-radius: 4px;
  background: var(--surface);
  color: var(--ink);
  font: 15px/1 var(--sans);
  padding: 9px 11px;
  min-height: 38px;
  transition: border-color 0.16s ease, box-shadow 0.16s ease;
}

.field input[type="number"] {
  font-variant-numeric: tabular-nums;
}

.field select {
  background-image: linear-gradient(45deg, transparent 49%, var(--ink-3) 50%),
    linear-gradient(135deg, var(--ink-3) 50%, transparent 51%);
  background-position: calc(100% - 15px) 16px, calc(100% - 10px) 16px;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  padding-right: 30px;
}

.field input:focus,
.field select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.field__unit {
  position: absolute;
  right: 11px;
  font-size: 12.5px;
  color: var(--ink-3);
  pointer-events: none;
}

.field input[type="number"] {
  padding-right: 34px;
}

.formerr {
  margin-top: 10px;
  background: var(--warn-soft);
  color: var(--warn);
  font-size: 12.5px;
  padding: 8px 10px;
  border-radius: 4px;
}

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

.presets {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.presets__label {
  font-size: 11.5px;
  color: var(--ink-3);
  margin-bottom: 8px;
}

.presets__row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.chip {
  appearance: none;
  border: 1px solid var(--line);
  background: var(--surface-2);
  color: var(--ink-2);
  font: 500 12px/1 var(--sans);
  padding: 7px 10px;
  border-radius: 999px;
  cursor: pointer;
  transition: background 0.16s ease, color 0.16s ease, border-color 0.16s ease;
}

.chip:hover {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
}

.chip:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ----------------------------------------------------------------- guide -- */

.guide {
  margin-top: 16px;
  border-top: 1px solid var(--line);
  padding-top: 12px;
}

.guide summary {
  font-size: 12.5px;
  color: var(--ink-2);
  cursor: pointer;
  list-style: none;
}

.guide summary::-webkit-details-marker {
  display: none;
}

.guide summary::before {
  content: "+";
  display: inline-block;
  width: 16px;
  color: var(--ink-3);
  font-family: var(--mono);
}

.guide[open] summary::before {
  content: "\2212";
}

.guide__body {
  margin-top: 12px;
  display: grid;
  gap: 10px;
  font-size: 12.5px;
  color: var(--ink-2);
}

.guide__step {
  display: grid;
  gap: 3px;
  padding: 9px 11px;
  background: var(--surface-2);
  border-radius: 4px;
}

.guide__step strong {
  font: 600 12px/1.3 var(--mono);
  color: var(--ink);
}

.guide__step em {
  font-style: normal;
  color: var(--ink-3);
}

/* ---------------------------------------------------------------- result -- */

.result-empty {
  display: grid;
  gap: 10px;
  padding: 18px;
  background: var(--surface-2);
  border-radius: 4px;
  color: var(--ink-2);
  font-size: 14px;
  max-width: 66ch;
}

.result-empty ol {
  margin: 0;
  padding-left: 20px;
  display: grid;
  gap: 5px;
}

.verdict {
  display: grid;
  gap: 6px;
}

.verdict__label {
  font-size: 11.5px;
  color: var(--ink-3);
}

.verdict__value {
  font-size: clamp(24px, 2.9vw, 34px);
  line-height: 1.1;
  font-weight: 660;
  letter-spacing: -0.028em;
  text-wrap: balance;
}

.verdict__meta {
  font-size: 12.5px;
  color: var(--ink-2);
}

.verdict__meta code {
  background: var(--accent-soft);
  color: var(--accent);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font: 500 11.5px/1 var(--sans);
  padding: 5px 8px;
  border-radius: 3px;
  background: var(--surface-3);
  color: var(--ink-2);
}

.badge--ok {
  background: var(--true-soft);
  color: var(--true);
}

.badge--bad {
  background: var(--warn-soft);
  color: var(--warn);
}

.verdict__row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin-top: 4px;
}

.verdict__row .spacer {
  flex: 1;
}

/* ----------------------------------------------------------------- trace -- */

.trace {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.trace h3,
.corr h3 {
  font-size: 13px;
  color: var(--ink-2);
  font-weight: 600;
  margin-bottom: 10px;
}

.steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 2px;
}

.step {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr) auto;
  gap: 10px;
  align-items: center;
  padding: 7px 9px;
  border-radius: 3px;
  background: var(--surface-2);
  font-size: 12.5px;
}

.step--off {
  background: var(--false-soft);
  color: var(--ink-2);
}

.step--stop {
  outline: 1px dashed var(--line-strong);
  outline-offset: -1px;
}

.step__id {
  font: 600 11.5px/1 var(--mono);
  color: var(--ink-2);
}

.step__cond {
  font: 12px/1.3 var(--mono);
  color: var(--ink);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.step--off .step__cond {
  color: var(--ink-2);
}

.step__branch {
  font: 600 11px/1 var(--mono);
  color: var(--ink-3);
  white-space: nowrap;
}

.step__branch b {
  color: var(--true);
  font-weight: 700;
}

.step--off .step__branch b {
  color: var(--false);
}

/* ------------------------------------------------------------- correction -- */

.corr {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  display: grid;
  gap: 16px;
}

.corr__intro {
  font-size: 13.5px;
  color: var(--ink-2);
  max-width: 70ch;
}

.corr__intro b {
  color: var(--ink);
}

.keycase {
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}

.keycase__head {
  padding: 9px 12px;
  background: var(--surface-2);
  font-size: 12px;
  color: var(--ink-2);
  display: flex;
  flex-wrap: wrap;
  gap: 4px 12px;
  align-items: baseline;
}

.keycase__head b {
  font: 600 11.5px/1 var(--mono);
  color: var(--ink);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12.5px;
}

th,
td {
  text-align: left;
  padding: 7px 12px;
  border-top: 1px solid var(--line);
  vertical-align: top;
}

th {
  font-weight: 600;
  font-size: 11.5px;
  color: var(--ink-3);
  background: var(--surface);
  border-top: 0;
}

td.num {
  font-variant-numeric: tabular-nums;
  font-family: var(--mono);
  font-size: 12px;
}

tr.differs td {
  background: var(--accent-soft);
}

tr.differs td:first-child::after {
  content: " beda";
  font: 500 10.5px/1 var(--sans);
  color: var(--accent);
  margin-left: 6px;
  vertical-align: 1px;
}

.cands {
  display: grid;
  gap: 6px;
}

.cands__label {
  font-size: 12.5px;
  color: var(--ink-2);
  margin-bottom: 2px;
}

.cand {
  display: grid;
  grid-template-columns: 16px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
  padding: 9px 11px;
  border: 1px solid var(--line);
  border-radius: 4px;
  cursor: pointer;
  transition: border-color 0.14s ease, background 0.14s ease;
}

.cand:hover {
  border-color: var(--line-strong);
  background: var(--surface-2);
}

.cand input {
  margin: 3px 0 0;
  accent-color: var(--accent);
}

.cand__cond {
  display: block;
  font: 600 12.5px/1.3 var(--mono);
  color: var(--ink);
}

.cand__why {
  display: block;
  font-size: 11.5px;
  color: var(--ink-3);
  margin-top: 2px;
}

.cand.is-selected {
  border-color: var(--accent);
  background: var(--accent-soft);
}

.cand.is-selected .cand__why {
  color: var(--accent);
}

.corr__foot {
  display: grid;
  gap: 10px;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
}

.corr__note {
  font-size: 12px;
  color: var(--ink-3);
}

.verif {
  display: grid;
  gap: 8px;
  padding: 14px;
  border-radius: 4px;
  background: var(--true-soft);
}

.verif h3 {
  font-size: 13px;
  color: var(--true);
  margin-bottom: 2px;
}

.verif ul {
  margin: 0;
  padding-left: 18px;
  display: grid;
  gap: 4px;
  font-size: 13px;
  color: var(--ink);
}

.verif code {
  background: rgba(255, 255, 255, 0.7);
}

/* ------------------------------------------------------------------ tree -- */

.tree__scroll {
  overflow: auto;
  padding: 6px 2px 10px;
  max-height: 560px;
}

.tree__canvas {
  position: relative;
  min-height: 120px;
}

.edge {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: visible;
}

.edge line {
  stroke: var(--line-strong);
  stroke-width: 1.1;
}

.edge line.is-on {
  stroke: var(--accent);
  stroke-width: 1.7;
}

.edge line.is-ghost {
  stroke-dasharray: 3 4;
  stroke: var(--line-strong);
}

.edge-label {
  position: absolute;
  transform: translate(-50%, -50%);
  font: 600 10px/1 var(--mono);
  background: var(--ground);
  color: var(--ink-3);
  padding: 2px 3px;
  border-radius: 2px;
}

.edge-label.is-on {
  background: var(--accent);
  color: #fff;
}

.node {
  position: absolute;
  width: 182px;
  height: 88px;
  overflow: hidden;
  padding: 9px 11px 10px;
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: 4px;
  transition: background 0.18s ease, border-color 0.18s ease, opacity 0.18s ease;
}

.node__id {
  display: block;
  font: 600 10.5px/1 var(--mono);
  color: var(--ink-3);
  letter-spacing: 0.02em;
}

.node__cond {
  margin-top: 6px;
  font: 600 12px/1.3 var(--mono);
  color: var(--ink);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.node__concl {
  margin-top: 6px;
  font-size: 11.5px;
  line-height: 1.25;
  color: var(--ink-2);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.node__concl::before {
  content: "\2192  ";
  color: var(--ink-3);
}

.node.is-on {
  border-color: var(--accent);
  background: var(--accent-soft);
}

.node.is-off {
  border-style: dashed;
  opacity: 0.72;
}

.node.is-stop {
  box-shadow: 0 0 0 2px var(--accent);
}

.node.is-new {
  animation: node-in 0.55s cubic-bezier(0.2, 0.8, 0.3, 1);
}

.node.is-root .node__cond {
  font-style: normal;
}

@keyframes node-in {
  from {
    opacity: 0;
    transform: translateY(-8px) scale(0.97);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.ghost {
  position: absolute;
  width: 182px;
  padding: 10px 11px;
  border: 1px dashed var(--accent);
  border-radius: 4px;
  color: var(--accent);
  font: 500 11.5px/1.3 var(--sans);
  background: rgba(228, 236, 246, 0.5);
  pointer-events: none;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 16px;
  list-style: none;
  margin: 0;
  padding: 0;
  font-size: 11.5px;
  color: var(--ink-2);
}

.legend li {
  display: flex;
  align-items: center;
  gap: 6px;
}

.dot {
  width: 9px;
  height: 9px;
  border-radius: 2px;
  border: 1px solid var(--line-strong);
  background: var(--surface);
}

.dot--on {
  background: var(--accent-soft);
  border-color: var(--accent);
}

.dot--off {
  border-style: dashed;
  background: var(--surface-2);
}

.dot--stop {
  box-shadow: 0 0 0 2px var(--accent);
  border-color: var(--accent);
}

/* ------------------------------------------------------------------- log -- */

.log-empty {
  font-size: 13px;
  color: var(--ink-3);
  padding: 10px 0 4px;
}

#log table {
  font-size: 12.5px;
}

#log {
  overflow-x: auto;
}

#log table {
  min-width: 560px;
}

#log td.act {
  white-space: nowrap;
}

#log td.case {
  color: var(--ink-2);
  font-size: 12px;
}

/* ----------------------------------------------------------------- toast -- */

.toast {
  position: fixed;
  left: 50%;
  bottom: 26px;
  transform: translate(-50%, 14px);
  background: var(--ink);
  color: #fff;
  font-size: 13px;
  padding: 10px 16px;
  border-radius: 4px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.22s ease, transform 0.22s ease;
  max-width: min(90vw, 46ch);
  text-align: center;
}

.toast.is-on {
  opacity: 1;
  transform: translate(-50%, 0);
}

/* ------------------------------------------------------------------ foot -- */

.foot {
  margin-top: 22px;
  font-size: 12px;
  color: var(--ink-3);
}

/* ----------------------------------------------------------------- phone -- */

@media (max-width: 1080px) {
  .board {
    grid-template-columns: minmax(0, 1fr);
  }

  .head {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas: "main" "meta" "act";
  }

  .kbmeta {
    gap: 22px;
  }
}

@media (max-width: 620px) {
  .shell {
    padding: 20px 16px 56px;
  }

  h1 {
    font-size: 26px;
  }

  .card {
    padding: 16px;
  }

  .corr__foot {
    grid-template-columns: minmax(0, 1fr);
  }

  .step {
    grid-template-columns: 40px minmax(0, 1fr);
  }

  .step__branch {
    grid-column: 2;
    color: var(--ink-3);
  }

  table {
    font-size: 12px;
  }

  th,
  td {
    padding: 6px 8px;
  }
}

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