:root {
  color-scheme: dark;
  --bg: #0d0d0c;
  --panel: #171716;
  --panel-2: #20201e;
  --line: #48453f;
  --line-soft: #2d2b28;
  --text: #eee9dd;
  --muted: #aaa294;
  --gold: #c7a35c;
  --gold-2: #f0cc7a;
  --danger: #e8836f;
  --steel: #b9c0c2;
  --shadow: rgba(0, 0, 0, 0.45);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    linear-gradient(180deg, rgba(199, 163, 92, 0.08), transparent 280px),
    radial-gradient(circle at 50% 0%, rgba(185, 192, 194, 0.08), transparent 34rem),
    var(--bg);
  color: var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button,
input,
select {
  font: inherit;
}

.app-shell {
  width: min(1180px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 56px 0 48px;
}

.masthead {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 18px;
}

.eyebrow {
  margin: 0 0 4px;
  color: var(--gold-2);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(1.75rem, 3.1vw, 3rem);
  line-height: 1.05;
  letter-spacing: 0;
}

.subtitle {
  max-width: 680px;
  margin: 10px 0 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.45;
}

.plate-count {
  display: grid;
  gap: 8px;
  min-width: 132px;
  color: var(--muted);
  font-weight: 700;
}

.plate-count select {
  appearance: none;
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background:
    linear-gradient(45deg, transparent 50%, var(--gold-2) 50%) right 17px center / 6px 6px no-repeat,
    linear-gradient(135deg, var(--gold-2) 50%, transparent 50%) right 11px center / 6px 6px no-repeat,
    var(--panel-2);
  color: var(--text);
  padding: 0 34px 0 12px;
}

.solver-panel,
.messages,
.result {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.03), transparent), var(--panel);
  box-shadow: 0 24px 60px var(--shadow);
}

.solver-panel {
  padding: 18px;
}

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

.lock-table {
  width: 100%;
  min-width: 920px;
  border-collapse: collapse;
  table-layout: fixed;
}

.lock-table th,
.lock-table td {
  border-bottom: 1px solid var(--line-soft);
  padding: 10px 8px;
  text-align: center;
  vertical-align: middle;
}

.lock-table th {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.lock-table tr:last-child td {
  border-bottom: 0;
}

.plate-head {
  width: 76px;
}

.link-head {
  width: 154px;
}

.plate-number {
  border-right: 1px solid var(--line-soft);
  color: rgba(185, 192, 194, 0.72);
  font-weight: 900;
  font-size: 1.04rem;
}

.plate-number-right {
  border-right: 0;
  border-left: 1px solid var(--line-soft);
  color: rgba(185, 192, 194, 0.48);
  font-size: 0.92rem;
}

.lock-table tr:last-child .plate-number {
  border-bottom: 0;
}

.center-col,
.center-cell {
  background: rgba(199, 163, 92, 0.08);
}

.position-radio {
  display: inline-grid;
  place-items: center;
  width: 28px;
  height: 28px;
}

.position-radio input {
  position: absolute;
  opacity: 0;
}

.position-radio span {
  width: 18px;
  height: 18px;
  border: 2px solid #77746c;
  border-radius: 50%;
  background: #0f0f0e;
  box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.08);
}

.position-radio input:focus-visible + span {
  outline: 2px solid var(--gold-2);
  outline-offset: 3px;
}

.position-radio input:checked + span {
  border-color: var(--gold-2);
  background: radial-gradient(circle, var(--gold-2) 0 35%, #5f4822 38% 100%);
}

.link-input {
  width: 100%;
  min-height: 38px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #111110;
  color: var(--text);
  padding: 0 10px;
  text-align: center;
}

.link-input:focus {
  border-color: var(--gold);
  outline: 2px solid rgba(199, 163, 92, 0.24);
}

.link-input.invalid {
  border-color: var(--danger);
}

.actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-top: 18px;
}

.action-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.solve-button,
.reset-button {
  min-width: 132px;
  min-height: 46px;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 900;
  text-transform: uppercase;
}

.solve-button {
  border: 1px solid #e2bd72;
  background: linear-gradient(180deg, #d8b66d, #9e752e);
  color: #15110a;
}

.reset-button {
  border: 1px solid var(--line);
  background: #111110;
  color: var(--steel);
}

.reset-button:hover,
.reset-button:focus-visible {
  border-color: var(--gold);
  color: var(--gold-2);
}

.solve-button:disabled {
  cursor: wait;
  opacity: 0.7;
}

.hint {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.hint span {
  color: var(--steel);
}

.messages,
.result {
  display: none;
  margin-top: 16px;
  padding: 16px 18px;
}

.messages.visible,
.result.visible {
  display: block;
}

.messages h2,
.result h2 {
  margin: 0 0 10px;
  font-size: 1rem;
}

.messages ul {
  margin: 0;
  padding-left: 18px;
  color: var(--danger);
}

.solution-line {
  margin: 0;
  color: var(--gold-2);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: clamp(1.45rem, 4vw, 2.4rem);
  line-height: 1.25;
  overflow-wrap: anywhere;
}

.solution-line p {
  margin: 0 0 6px;
}

.solution-line p:last-child {
  margin-bottom: 0;
}

.status {
  margin: 0;
  color: var(--muted);
}

.steps {
  width: 100%;
  margin-top: 16px;
  border-collapse: collapse;
}

.steps th,
.steps td {
  border-top: 1px solid var(--line-soft);
  padding: 10px 8px;
  text-align: left;
}

.steps th {
  color: var(--muted);
  font-size: 0.78rem;
  text-transform: uppercase;
}

.steps td:nth-child(2),
.steps td:nth-child(3) {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.seo-copy {
  margin-top: 40px;
  padding: 40px 0 8px;
}

.seo-copy-inner {
  max-width: 900px;
}

.seo-copy h2,
.seo-copy h3 {
  margin: 0;
  color: var(--text);
  font-family: Georgia, "Times New Roman", serif;
  letter-spacing: 0;
}

.seo-copy h2 {
  font-size: clamp(1.65rem, 3vw, 2.6rem);
  line-height: 1.08;
}

.seo-copy h3 {
  margin-top: 24px;
  font-size: 1.25rem;
  line-height: 1.2;
}

.seo-copy p,
.seo-copy li {
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.85;
}

.seo-copy p {
  margin: 18px 0 0;
}

.seo-copy ol {
  margin: 18px 0 0;
  padding-left: 22px;
}

.seo-copy li + li {
  margin-top: 10px;
}

.language-footer {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
  justify-content: space-between;
  margin-top: 22px;
  padding-top: 16px;
  border-top: 1px solid var(--line-soft);
  color: rgba(170, 162, 148, 0.66);
  font-size: 0.82rem;
}

.language-footer p {
  margin: 0;
}

.language-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  align-items: center;
}

.language-footer a {
  color: rgba(170, 162, 148, 0.78);
  text-decoration: none;
}

.language-footer a:hover,
.language-footer a:focus-visible {
  color: var(--gold-2);
  text-decoration: underline;
  text-decoration-color: rgba(240, 204, 122, 0.42);
  text-underline-offset: 4px;
}

@media (max-width: 720px) {
  .app-shell {
    width: min(100vw - 20px, 1180px);
    padding-top: 36px;
  }

  .masthead,
  .actions {
    align-items: stretch;
    flex-direction: column;
  }

  .action-buttons {
    display: grid;
    grid-template-columns: 1fr;
  }

  .plate-count {
    min-width: 0;
  }

  .solver-panel {
    padding: 12px;
  }

  .seo-copy {
    margin-top: 32px;
    padding-top: 32px;
  }
}