:root {
  --text: #1c2430;
  --muted: #55606e;
  --bg: #f5f7fa;
  --panel: #ffffff;
  --border: #cfd6df;
  --accent: #1a56b8;
  --accent-dark: #123f88;
  --accent-soft: #e6eefb;
  --error: #b3261e;
  --error-soft: #fdecea;
  --shift: #8a4b00;
  --shift-soft: #fff1dc;
  --focus: #f0a400;
}

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

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

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
  overflow-wrap: anywhere;
}

.skip-link {
  position: absolute;
  left: 0.5rem;
  top: -3rem;
  padding: 0.5rem 0.75rem;
  background: var(--panel);
  color: var(--accent-dark);
  border: 2px solid var(--accent);
  border-radius: 6px;
  z-index: 10;
}

.skip-link:focus {
  top: 0.5rem;
}

.site-header,
main,
.site-footer {
  width: 100%;
  max-width: 64rem;
  margin: 0 auto;
  padding: 0 1rem;
}

.site-header {
  padding-top: 1.5rem;
}

h1 {
  font-size: 1.6rem;
  line-height: 1.25;
  margin: 0 0 0.5rem;
}

h2 {
  font-size: 1.2rem;
  margin: 0 0 0.75rem;
}

h3 {
  font-size: 1rem;
  margin: 1rem 0 0.25rem;
}

.lead {
  margin: 0 0 1rem;
  color: var(--muted);
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem;
  margin: 0 0 1rem;
}

.hint,
.help {
  color: var(--muted);
}

.hint {
  margin: 0 0 0.75rem;
}

.fields {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.25rem 1rem;
}

.field label {
  display: block;
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.field input {
  display: block;
  width: 100%;
  max-width: 100%;
  font: inherit;
  padding: 0.5rem 0.625rem;
  border: 1px solid #8a95a3;
  border-radius: 6px;
  background: #fff;
  color: var(--text);
}

.field input[aria-invalid="true"] {
  border-color: var(--error);
  box-shadow: 0 0 0 1px var(--error);
}

.help {
  font-size: 0.875rem;
  margin: 0.25rem 0 0.5rem;
}

.error {
  color: var(--error);
  background: var(--error-soft);
  border-left: 4px solid var(--error);
  padding: 0.375rem 0.625rem;
  margin: 0.25rem 0 0.75rem;
  font-weight: 600;
}

.error[hidden] {
  display: none;
}

button {
  font: inherit;
  cursor: pointer;
  border-radius: 6px;
  padding: 0.5rem 1rem;
  min-height: 2.75rem;
}

button.primary {
  background: var(--accent);
  border: 2px solid var(--accent);
  color: #fff;
  font-weight: 600;
}

button.primary:hover {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
}

button.secondary {
  background: #fff;
  border: 2px solid var(--accent);
  color: var(--accent-dark);
  font-weight: 600;
}

button.secondary:hover {
  background: var(--accent-soft);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

.zone-buttons {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 9.5rem), 1fr));
  gap: 0.5rem;
}

button.zone {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
  background: #fff;
  border: 2px solid var(--border);
  color: var(--text);
  padding: 0.5rem 0.75rem;
}

button.zone .zone-city {
  font-weight: 600;
}

button.zone .zone-id {
  font-size: 0.8rem;
  color: var(--muted);
}

button.zone[aria-pressed="true"] {
  background: var(--accent-soft);
  border-color: var(--accent);
}

button.zone[aria-pressed="true"] .zone-city::before {
  content: "✓ ";
  color: var(--accent);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 0 0 0.5rem;
}

.status {
  min-height: 1.5rem;
  margin: 0 0 1rem;
}

.status-error {
  color: var(--error);
  font-weight: 600;
}

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

.stale-note {
  background: var(--shift-soft);
  color: var(--shift);
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  font-weight: 600;
}

.summary {
  margin: 0 0 0.75rem;
  font-weight: 600;
}

.zone-results {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 18rem), 1fr));
  gap: 0.75rem;
}

.zone-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.75rem;
  min-width: 0;
}

.zone-card.shifted {
  border-color: var(--shift);
  border-left-width: 5px;
}

.zone-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

.zone-card .zone-id {
  font-weight: 400;
  font-size: 0.8rem;
  color: var(--muted);
}

.zone-card dl {
  margin: 0;
}

.time-row {
  display: grid;
  grid-template-columns: 3rem 1fr;
  gap: 0.5rem;
  margin: 0 0 0.25rem;
}

.time-row dt {
  font-weight: 600;
  color: var(--muted);
}

.time-row dd {
  margin: 0;
  min-width: 0;
}

.local {
  font-variant-numeric: tabular-nums;
  font-weight: 600;
}

.offset {
  display: inline-block;
  font-variant-numeric: tabular-nums;
  color: var(--accent-dark);
  background: var(--accent-soft);
  border-radius: 4px;
  padding: 0 0.3rem;
}

.day-shift {
  display: inline-block;
  color: var(--shift);
  background: var(--shift-soft);
  border: 1px solid var(--shift);
  border-radius: 4px;
  padding: 0 0.3rem;
  font-weight: 700;
}

.note {
  margin: 0.5rem 0 0;
  font-size: 0.875rem;
  color: var(--shift);
}

.explain p {
  margin: 0 0 0.5rem;
}

.site-footer {
  color: var(--muted);
  font-size: 0.875rem;
  padding-bottom: 1.5rem;
}

.noscript {
  max-width: 64rem;
  margin: 0 auto 1rem;
  padding: 1rem;
  color: var(--error);
}

@media (min-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  .fields {
    grid-template-columns: 1fr 1fr;
  }

  .panel {
    padding: 1.25rem 1.5rem;
  }
}