:root {
  color-scheme: light dark;
  --bg: #f5f6f8;
  --surface: #ffffff;
  --text: #16181d;
  --muted: #4d5563;
  --border: #dde1e7;
  --accent: #1d4ed8;
  --accent-text: #ffffff;
  --code-bg: #eef1f5;
  --danger: #b42318;
  --radius: 14px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "Cascadia Code", "SFMono-Regular", Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1115;
    --surface: #171a21;
    --text: #eceef2;
    --muted: #a3aab6;
    --border: #2a2f3a;
    --accent: #7aa2ff;
    --accent-text: #0f1115;
    --code-bg: #222733;
    --danger: #ff8a80;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.55;
}

.page {
  max-width: 820px;
  margin: 0 auto;
  padding: 48px 16px 24px;
  display: grid;
  gap: 20px;
}

.hero h1 {
  margin: 0.2em 0;
  font-size: clamp(1.9rem, 5vw, 2.8rem);
  line-height: 1.15;
}

.eyebrow {
  margin: 0;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  font-size: 0.85rem;
}

.lead {
  margin: 0;
  color: var(--muted);
  font-size: 1.1rem;
}

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

.card h2 {
  margin: 0 0 12px;
  font-size: 1.2rem;
}

.hint {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 0.92rem;
}

code {
  font-family: var(--mono);
  background: var(--code-bg);
  padding: 0.1em 0.35em;
  border-radius: 6px;
  font-size: 0.92em;
  overflow-wrap: anywhere;
}

.facts {
  margin: 0;
  display: grid;
  gap: 12px;
}

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

.facts dt {
  color: var(--muted);
  font-size: 0.85rem;
}

.facts dd {
  margin: 0;
}

.table-wrap {
  overflow-x: auto;
  margin-top: 8px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
}

th,
td {
  text-align: left;
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}

td {
  font-family: var(--mono);
  overflow-wrap: anywhere;
}

th {
  color: var(--muted);
  font-weight: 600;
}

.lookup {
  display: grid;
  gap: 12px;
}

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

label {
  font-weight: 600;
  font-size: 0.92rem;
}

input,
select,
button,
.button {
  font: inherit;
  border-radius: 10px;
  min-height: 44px;
}

input,
select {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
}

input[aria-invalid="true"] {
  border-color: var(--danger);
}

button,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 20px;
  border: 0;
  background: var(--accent);
  color: var(--accent-text);
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
}

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

.result {
  margin-top: 12px;
}

.steps {
  margin: 0;
  padding-left: 1.3em;
  display: grid;
  gap: 8px;
}

.footer {
  max-width: 820px;
  margin: 0 auto;
  padding: 0 16px 40px;
  color: var(--muted);
  font-size: 0.85rem;
}

@media (min-width: 640px) {
  .page {
    padding-top: 72px;
  }

  .facts {
    grid-template-columns: repeat(3, 1fr);
  }

  .lookup {
    grid-template-columns: 1fr 140px auto;
    align-items: end;
  }
}