:root {
  color-scheme: light;
  --ink: #15231f;
  --ink-soft: #34483f;
  --muted: #67766f;
  --canvas: #f3f5f0;
  --surface: #fffefb;
  --surface-soft: #f5f9f6;
  --line: #d9dfda;
  --line-strong: #bdc9c2;
  --brand: #08745b;
  --brand-strong: #045341;
  --brand-soft: #e1f2eb;
  --accent: #d99a18;
  --accent-soft: #fff4d8;
  --danger: #a44132;
  --danger-soft: #fae9e6;
  --focus: #0b6fdf;
  --shadow: 0 20px 55px rgba(26, 52, 42, 0.08);
  --shadow-soft: 0 8px 25px rgba(26, 52, 42, 0.07);
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 11px;
  font-family: Inter, "Noto Sans SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% 0%, rgba(217, 154, 24, 0.13), transparent 28rem),
    radial-gradient(circle at 94% 7%, rgba(8, 116, 91, 0.11), transparent 31rem),
    var(--canvas);
}

body::before {
  position: fixed;
  z-index: -1;
  inset: 0;
  background-image:
    linear-gradient(rgba(21, 35, 31, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(21, 35, 31, 0.025) 1px, transparent 1px);
  background-size: 36px 36px;
  content: "";
  pointer-events: none;
}

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

h1,
h2,
strong {
  text-wrap: balance;
}

button,
input,
select,
summary {
  font: inherit;
}

button,
select,
summary {
  cursor: pointer;
}

.shell {
  width: min(1240px, calc(100% - 40px));
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  z-index: 20;
  top: 10px;
  left: 10px;
  padding: 10px 14px;
  border-radius: 9px;
  color: #fff;
  background: var(--brand-strong);
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 360px);
  gap: 32px;
  align-items: end;
  padding: 38px 0 24px;
}

.brand-block {
  max-width: 760px;
}

.eyebrow {
  margin-bottom: 9px;
  color: var(--brand);
  font-size: 0.73rem;
  font-weight: 850;
  letter-spacing: 0.19em;
}

h1 {
  margin-bottom: 11px;
  font-size: clamp(2.25rem, 5vw, 4.35rem);
  line-height: 0.98;
  letter-spacing: -0.052em;
}

h2 {
  margin-bottom: 6px;
  font-size: clamp(1.35rem, 2vw, 1.8rem);
  letter-spacing: -0.025em;
}

.hero-copy {
  max-width: 650px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.65;
}

.status-card {
  display: grid;
  gap: 5px;
  min-height: 108px;
  padding: 17px 19px;
  border: 1px solid rgba(8, 116, 91, 0.22);
  border-radius: var(--radius-md);
  background: rgba(245, 252, 248, 0.9);
  box-shadow: var(--shadow-soft);
}

.status-card strong {
  font-size: 1rem;
}

.status-card span {
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.5;
}

.status-card.error {
  border-color: rgba(164, 65, 50, 0.35);
  color: var(--danger);
  background: var(--danger-soft);
}

main {
  display: grid;
  gap: 18px;
}

.panel {
  border: 1px solid rgba(21, 35, 31, 0.12);
  border-radius: var(--radius-lg);
  background: rgba(255, 254, 251, 0.95);
  box-shadow: var(--shadow);
}

.query-panel,
.result-panel {
  padding: 24px;
}

.section-heading,
.result-heading {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: end;
}

.section-heading > p {
  max-width: 440px;
  margin-bottom: 5px;
  color: var(--muted);
  font-size: 0.88rem;
  text-align: right;
}

form {
  display: grid;
  gap: 20px;
  margin-top: 22px;
}

.primary-query-grid {
  display: grid;
  grid-template-columns: minmax(210px, 0.85fr) minmax(360px, 1.8fr) minmax(270px, 1.1fr) minmax(145px, 0.55fr);
  gap: 16px;
  align-items: start;
}

.field,
.field-group {
  display: grid;
  gap: 7px;
  min-width: 0;
}

.field label,
.field-group legend {
  padding: 0;
  color: var(--ink-soft);
  font-size: 0.79rem;
  font-weight: 760;
  line-height: 1.5;
}

.field-group {
  margin: 0;
  padding: 0;
  border: 0;
}

.field-help,
.primary-action small {
  color: var(--muted);
  font-size: 0.72rem;
  line-height: 1.35;
}

input,
select,
button {
  width: 100%;
  min-height: 46px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
  color: var(--ink);
  background: #fff;
}

input::placeholder {
  color: #8a9790;
}

input:hover,
select:hover,
button:hover:not(:disabled) {
  border-color: #8fa49a;
}

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

button {
  font-weight: 760;
}

button.primary {
  border-color: var(--brand);
  color: #fff;
  background: var(--brand);
  box-shadow: 0 9px 22px rgba(8, 116, 91, 0.2);
}

button.primary:hover:not(:disabled) {
  border-color: var(--brand-strong);
  background: var(--brand-strong);
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.48;
}

.route-fields {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 44px minmax(0, 1fr);
  gap: 9px;
  align-items: end;
  min-width: 0;
}

.route-fields.single-location {
  grid-template-columns: minmax(0, 1fr);
}

.swap-field {
  display: grid;
  align-items: end;
  padding-bottom: 1px;
}

.icon-button {
  display: grid;
  width: 44px;
  min-height: 46px;
  place-items: center;
  padding: 0;
  border-color: rgba(8, 116, 91, 0.28);
  color: var(--brand-strong);
  background: var(--brand-soft);
}

.icon-button span[aria-hidden="true"] {
  font-size: 1.12rem;
}

.swap-label {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
}

.date-fields,
.inline-fields {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  gap: 8px;
  align-items: center;
}

.date-fields {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.inline-fields span {
  color: var(--muted);
  font-size: 0.78rem;
}

.primary-action {
  display: grid;
  gap: 6px;
  margin-top: calc(0.79rem * 1.5 + 7px);
}

.advanced-filters {
  border-top: 1px solid var(--line);
}

.advanced-filters summary {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  padding: 16px 3px 0;
  color: var(--ink-soft);
  list-style-position: inside;
}

.advanced-filters summary > span:first-child {
  display: inline-grid;
  gap: 2px;
  margin-left: 5px;
}

.advanced-filters summary small {
  color: var(--muted);
  font-size: 0.74rem;
  font-weight: 450;
}

.filter-count {
  padding: 4px 9px;
  border: 1px solid rgba(8, 116, 91, 0.2);
  border-radius: 999px;
  color: var(--brand-strong);
  background: var(--brand-soft);
  font-size: 0.72rem;
  font-weight: 760;
  white-space: nowrap;
}

.advanced-body {
  margin-top: 14px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface-soft);
}

.advanced-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  align-items: end;
}

.checkbox-field {
  min-height: 46px;
  align-content: center;
}

.checkbox-field label {
  display: flex;
  gap: 9px;
  align-items: center;
  min-height: 44px;
}

.checkbox-field input {
  width: 18px;
  min-height: 18px;
  height: 18px;
  margin: 0;
}

.advanced-actions {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: center;
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.advanced-actions p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.76rem;
}

.text-button {
  width: auto;
  min-height: 36px;
  padding: 6px 10px;
  border-color: transparent;
  color: var(--brand-strong);
  background: transparent;
}

.text-button:hover:not(:disabled) {
  border-color: var(--line);
  background: #fff;
}

.result-panel {
  min-height: 500px;
}

.result-heading {
  padding-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.result-heading h2 {
  margin-bottom: 4px;
}

.result-status,
.result-meta {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.55;
}

.result-actions {
  display: flex;
  gap: 8px;
  flex: 0 0 auto;
}

.result-actions button {
  width: auto;
  min-height: 40px;
  padding: 8px 12px;
  font-size: 0.79rem;
}

.result-meta {
  margin-top: 13px;
}

.notice {
  margin: 15px 0 18px;
  padding: 12px 14px;
  border: 1px solid #edd69f;
  border-left: 4px solid var(--accent);
  border-radius: 9px;
  color: #66501f;
  background: var(--accent-soft);
  font-size: 0.82rem;
  line-height: 1.65;
}

.notice strong {
  margin-right: 4px;
}

.results.empty {
  display: grid;
  min-height: 250px;
  place-items: center;
  padding: 24px;
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius-md);
  color: var(--muted);
  background: #fbfcfa;
  text-align: center;
}

.results.error-state {
  border-color: rgba(164, 65, 50, 0.45);
  color: var(--danger);
  background: var(--danger-soft);
}

.result-list {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.flight-item,
.city-item,
.connection-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface);
  box-shadow: 0 4px 14px rgba(26, 52, 42, 0.035);
}

.flight-item {
  display: grid;
  grid-template-columns: 110px minmax(0, 1fr) minmax(130px, auto);
  gap: 18px;
  align-items: center;
  padding: 15px 16px;
}

.flight-identity {
  display: grid;
  gap: 3px;
}

.flight-identity strong {
  font-size: 1.04rem;
}

.flight-identity span,
.airport-stop span,
.route-track span,
.city-identity span,
.city-identity small,
.city-carriers,
.leg-heading span,
.leg-route span,
.connection-heading span,
.connection-total span {
  color: var(--muted);
  font-size: 0.72rem;
  line-height: 1.45;
}

.flight-route {
  display: grid;
  grid-template-columns: minmax(135px, 1fr) minmax(100px, 0.6fr) minmax(135px, 1fr);
  gap: 14px;
  align-items: center;
  min-width: 0;
}

.airport-stop {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 2px 10px;
  align-items: baseline;
  min-width: 0;
}

.airport-stop time {
  grid-row: span 2;
  font-size: clamp(1.45rem, 2.5vw, 1.9rem);
  font-weight: 780;
  letter-spacing: -0.04em;
}

.airport-stop strong {
  font-size: 0.84rem;
}

.airport-stop span {
  min-width: 0;
  overflow-wrap: anywhere;
}

.arrival-stop {
  text-align: right;
}

.arrival-stop time {
  grid-column: 2;
  justify-self: end;
}

.arrival-stop strong,
.arrival-stop span {
  grid-column: 1;
  grid-row: 1;
  justify-self: end;
}

.arrival-stop span {
  grid-row: 2;
}

.route-track {
  display: grid;
  gap: 6px;
  color: var(--muted);
  text-align: center;
}

.route-track i,
.leg-route i {
  position: relative;
  display: block;
  height: 1px;
  background: var(--line-strong);
}

.route-track i::after,
.leg-route i::after {
  position: absolute;
  top: -3px;
  right: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--brand);
  content: "";
}

.flight-tags {
  text-align: right;
}

.badge {
  display: inline-block;
  margin: 3px 0 3px 5px;
  padding: 4px 8px;
  border-radius: 999px;
  color: #405149;
  background: #eef1ef;
  font-size: 0.68rem;
  font-weight: 720;
  white-space: nowrap;
}

.badge.official {
  color: #17634d;
  background: #dff3ea;
}

.badge.inferred {
  color: #72520c;
  background: #fff0c9;
}

.badge.unknown {
  color: #7b2f27;
  background: #f4dddd;
}

.badge.plus {
  color: #27577e;
  background: #dce9f7;
}

.city-item {
  display: grid;
  grid-template-columns: minmax(150px, 0.55fr) minmax(0, 2fr) minmax(100px, auto);
  gap: 18px;
  align-items: center;
  padding: 16px;
}

.city-identity {
  display: grid;
  gap: 2px;
}

.city-identity strong {
  font-size: 1.06rem;
}

.city-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(90px, 1fr));
  gap: 12px;
  margin-bottom: 0;
}

.city-metrics div {
  min-width: 0;
}

.city-metrics dt {
  margin-bottom: 2px;
  color: var(--muted);
  font-size: 0.67rem;
}

.city-metrics dd {
  margin-bottom: 0;
  font-size: 0.79rem;
  font-weight: 710;
  overflow-wrap: anywhere;
}

.city-carriers {
  text-align: right;
}

.city-carriers span {
  display: block;
  margin-bottom: 3px;
  color: var(--muted);
  font-size: 0.67rem;
}

.connection-item {
  padding: 17px;
}

.connection-heading,
.connection-tags,
.leg-heading {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  align-items: center;
}

.connection-heading {
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line);
}

.connection-heading > div:first-child,
.connection-total {
  display: grid;
  gap: 2px;
}

.connection-total {
  text-align: right;
}

.connection-itinerary {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(150px, 0.55fr) minmax(0, 1fr);
  gap: 14px;
  align-items: stretch;
  margin-top: 14px;
}

.connection-leg,
.layover-stop {
  padding: 13px;
  border-radius: 12px;
  background: var(--surface-soft);
}

.leg-heading {
  margin-bottom: 10px;
}

.leg-route {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 50px minmax(0, 1fr);
  gap: 8px;
  align-items: center;
}

.leg-route > div {
  display: grid;
  gap: 2px;
}

.leg-route > div:last-child {
  text-align: right;
}

.leg-route time {
  font-size: 1.12rem;
  font-weight: 780;
}

.layover-stop {
  display: grid;
  place-content: center;
  color: #66501f;
  background: var(--accent-soft);
  text-align: center;
}

.layover-stop span {
  font-size: 0.72rem;
}

.layover-stop strong {
  margin-top: 3px;
  font-size: 0.8rem;
}

.connection-tags {
  justify-content: flex-start;
  flex-wrap: wrap;
  margin-top: 13px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  color: var(--muted);
  font-size: 0.76rem;
}

footer.shell {
  padding: 26px 0 42px;
  color: var(--muted);
  font-size: 0.78rem;
  text-align: center;
}

.hidden {
  display: none !important;
}

@media (max-width: 1120px) {
  .primary-query-grid {
    grid-template-columns: minmax(210px, 0.75fr) minmax(420px, 1.5fr);
  }

  .advanced-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .flight-item {
    grid-template-columns: 90px minmax(0, 1fr);
  }

  .flight-tags {
    grid-column: 1 / -1;
    text-align: left;
  }

  .badge {
    margin-right: 5px;
    margin-left: 0;
  }

  .city-item {
    grid-template-columns: 145px minmax(0, 1fr);
  }

  .city-carriers {
    grid-column: 1 / -1;
    text-align: left;
  }

  .city-carriers span {
    display: inline;
    margin-right: 5px;
  }
}

@media (max-width: 880px) {
  .site-header {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .status-card {
    min-height: auto;
  }

  .section-heading,
  .result-heading {
    align-items: start;
    flex-direction: column;
  }

  .section-heading > p {
    margin-bottom: 0;
    text-align: left;
  }

  .primary-query-grid {
    grid-template-columns: 1fr;
  }

  .primary-action {
    margin-top: 0;
  }

  .advanced-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .result-actions {
    width: 100%;
  }

  .result-actions button {
    flex: 1;
  }

  .flight-item,
  .city-item {
    grid-template-columns: 1fr;
  }

  .flight-identity {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    align-items: baseline;
  }

  .flight-tags,
  .city-carriers {
    grid-column: auto;
  }

  .connection-itinerary {
    grid-template-columns: 1fr;
  }

  .layover-stop {
    min-height: 70px;
  }
}

@media (max-width: 620px) {
  .shell {
    width: min(100% - 22px, 1240px);
  }

  .site-header {
    padding-top: 27px;
  }

  h1 {
    font-size: clamp(2.1rem, 12vw, 3.2rem);
  }

  .panel {
    border-radius: 18px;
  }

  .query-panel,
  .result-panel {
    padding: 16px;
  }

  .route-fields,
  .date-fields,
  .advanced-grid {
    grid-template-columns: 1fr;
  }

  .swap-field {
    justify-items: center;
    padding: 0;
  }

  .icon-button {
    width: auto;
    min-height: 36px;
    padding: 5px 13px;
  }

  .icon-button span[aria-hidden="true"] {
    transform: rotate(90deg);
  }

  .swap-label {
    position: static;
    width: auto;
    height: auto;
    clip-path: none;
    overflow: visible;
    font-size: 0.72rem;
  }

  .advanced-filters summary {
    align-items: start;
  }

  .advanced-body {
    padding: 14px;
  }

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

  .text-button {
    width: 100%;
    border-color: var(--line);
    background: #fff;
  }

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

  .route-track {
    grid-row: 2;
    grid-column: 1 / -1;
  }

  .arrival-stop {
    grid-row: 1;
    grid-column: 2;
  }

  .city-metrics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .connection-heading {
    align-items: start;
  }

  .leg-route {
    grid-template-columns: minmax(0, 1fr) 34px minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}