:root {
  color-scheme: light;
  --bg: #f4f6fb;
  --card-bg: #ffffff;
  --card-border: rgba(47, 55, 80, 0.08);
  --accent: #4c6ef5;
  --accent-soft: rgba(76, 110, 245, 0.16);
  --text: #1d2333;
  --text-muted: #5f6c92;
  --shadow-sm: 0 10px 22px rgba(32, 40, 62, 0.08);
  --font-base: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "Space Mono", "SFMono-Regular", ui-monospace, monospace;
  --radius-lg: 20px;
  --radius-md: 16px;
  --radius-sm: 8px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-base);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

.site-header {
  background: linear-gradient(135deg, rgba(76, 110, 245, 0.96), rgba(86, 199, 252, 0.85));
  color: #fff;
  padding: 56px 24px 48px;
  border-bottom-left-radius: 48px;
  border-bottom-right-radius: 48px;
  box-shadow: 0 20px 40px rgba(38, 55, 120, 0.18);
}

.site-header__content {
  max-width: 960px;
  margin: 0 auto;
}

.site-header h1 {
  margin: 0;
  font-size: clamp(2.35rem, 4vw, 3rem);
  letter-spacing: -0.02em;
}

.site-header p {
  margin: 12px 0 0;
  font-size: clamp(1.05rem, 2vw, 1.2rem);
  max-width: 640px;
}

.layout {
  max-width: 1180px;
  margin: -40px auto 72px;
  padding: 0 24px 24px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

.panel {
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--card-border);
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.panel--wide {
  grid-column: 1 / -1;
}

.panel__heading h2 {
  margin: 0;
  font-size: 1.1rem;
  font-weight: 600;
}

.panel__hint {
  margin: 6px 0 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.form-grid {
  display: grid;
  gap: 16px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.field__label {
  font-size: 0.92rem;
  font-weight: 500;
}

.field input[type="text"],
.field input[type="date"] {
  appearance: none;
  border: 1px solid rgba(44, 53, 83, 0.18);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font: inherit;
  color: inherit;
  background: rgba(255, 255, 255, 0.9);
  transition: border 0.2s ease, box-shadow 0.2s ease;
}

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

.field input.invalid {
  border-color: #ef4444;
}

.field__support {
  min-height: 1em;
  font-size: 0.8rem;
  color: #ef4444;
}

.button {
  font: inherit;
  border: none;
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.button:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 18px rgba(45, 60, 140, 0.25);
}

.button:active {
  transform: none;
  box-shadow: none;
}

.button--ghost {
  background: rgba(76, 110, 245, 0.1);
  color: var(--accent);
  border: 1px dashed rgba(76, 110, 245, 0.4);
  box-shadow: none;
}

.button--ghost:hover {
  background: rgba(76, 110, 245, 0.18);
  box-shadow: none;
}

.button--icon {
  width: 36px;
  height: 36px;
  padding: 0;
  font-size: 1.4rem;
  line-height: 1;
  background: rgba(29, 35, 51, 0.08);
  color: var(--text);
}

.traveler-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.traveler-card {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 16px;
  border-radius: var(--radius-md);
  background: rgba(240, 244, 255, 0.8);
  border: 1px solid rgba(106, 123, 180, 0.2);
}

.traveler-card__fields {
  flex: 1;
  display: grid;
  gap: 12px;
}

.insights {
  display: grid;
  gap: 20px;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.insight-card {
  background: rgba(244, 247, 255, 0.8);
  border-radius: var(--radius-md);
  border: 1px solid rgba(114, 133, 190, 0.18);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.insight-card h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.insight-card__body {
  display: flex;
  flex-direction: column;
  gap: 12px;
  color: var(--text-muted);
  font-size: 0.96rem;
}

.insight-card__body strong {
  color: var(--text);
}

.timeline {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid rgba(112, 124, 170, 0.18);
}

.timeline-row {
  display: grid;
  grid-template-columns: 180px minmax(720px, 1fr);
  min-width: max-content;
  border-bottom: 1px solid rgba(112, 124, 170, 0.12);
}

.timeline-row:last-child {
  border-bottom: none;
}

.row-label {
  padding: 14px 16px;
  border-right: 1px solid rgba(112, 124, 170, 0.12);
  background: rgba(246, 249, 255, 0.9);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.row-label strong {
  font-size: 0.95rem;
  color: var(--text);
}

.row-label span {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.timeline-hours {
  display: grid;
  grid-template-columns: repeat(24, minmax(48px, 1fr));
}

.hour-cell {
  padding: 10px 6px;
  border-right: 1px solid rgba(112, 124, 170, 0.08);
  border-bottom: 1px solid rgba(112, 124, 170, 0.08);
  display: flex;
  flex-direction: column;
  gap: 4px;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  line-height: 1.2;
  min-height: 62px;
  transition: background 0.2s ease;
  position: relative;
}

.timeline-row:last-child .hour-cell {
  border-bottom: none;
}

.hour-cell.waking {
  background: rgba(76, 110, 245, 0.14);
}

.hour-cell.sleeping {
  background: rgba(30, 38, 70, 0.08);
}

.hour-cell.shared {
  background: rgba(76, 110, 245, 0.22);
  color: #132f6b;
}

.hour-cell .hour-value {
  font-family: var(--font-mono);
  font-weight: 600;
}

.hour-cell .dow-value {
  font-size: 0.7rem;
  color: var(--text-muted);
}

.transition-icon {
  position: absolute;
  top: 6px;
  right: 8px;
  font-size: 0.75rem;
  line-height: 1;
  opacity: 0.85;
}

.transition-icon--sun {
  color: #f59e0b;
}

.transition-icon--moon {
  color: #3b82f6;
}

.sun-stripe {
  position: absolute;
  top: 6px;
  left: 8px;
  right: 8px;
  height: 3px;
  border-radius: 999px;
  background: linear-gradient(90deg, #f97316, #facc15);
  box-shadow: 0 0 4px rgba(249, 115, 22, 0.3);
}

.timeline-legend {
  display: flex;
  gap: 20px;
  margin-top: 12px;
  color: var(--text-muted);
  font-size: 0.85rem;
}

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

.legend-swatch {
  width: 16px;
  height: 16px;
  border-radius: 6px;
  border: 1px solid rgba(71, 81, 120, 0.2);
}

.legend-swatch--day {
  background: rgba(126, 190, 255, 0.5);
}

.legend-swatch--night {
  background: rgba(30, 38, 70, 0.15);
}

.legend-swatch--overlap {
  background: rgba(76, 110, 245, 0.3);
}

.empty-state {
  color: var(--text-muted);
  font-style: italic;
}

.combo {
  position: relative;
  display: block;
}

.combo input[type="text"] {
  width: 100%;
}

.combo__list {
  position: absolute;
  top: calc(100% + 4px);
  left: 0;
  right: 0;
  z-index: 10;
  background: #ffffff;
  border: 1px solid rgba(44, 53, 83, 0.18);
  border-radius: var(--radius-sm);
  box-shadow: 0 16px 32px rgba(28, 36, 70, 0.12);
  max-height: 220px;
  overflow-y: auto;
  padding: 4px;
}

.combo__item {
  width: 100%;
  text-align: left;
  border: none;
  background: transparent;
  padding: 8px 10px;
  border-radius: 6px;
  font: inherit;
  color: inherit;
  cursor: pointer;
}

.combo__item:hover,
.combo__item.is-active {
  background: rgba(76, 110, 245, 0.12);
}

@media (max-width: 960px) {
  .timeline-row {
    grid-template-columns: 140px minmax(640px, 1fr);
  }

  .row-label {
    padding: 10px 12px;
  }
}

@media (max-width: 720px) {
  .layout {
    margin-top: -24px;
    padding: 0 16px 16px;
  }

  .panel {
    padding: 20px;
  }

  .timeline-row {
    grid-template-columns: 140px minmax(560px, 1fr);
  }

  .hour-cell {
    min-height: 54px;
  }
}