:root {
  --bg: #f4f6f8;
  --card: #ffffff;
  --ink: #1a202c;
  --sub: #64748b;
  --line: #e2e8f0;
  --brand: #2b6cb0;
  --brand-weak: #ebf3fb;
  --danger: #c53030;
  --plus: #2f855a;
  --minus: #c53030;
  --radius: 12px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-text-size-adjust: 100%;
}

/* ---------- app bar ---------- */
.appbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 12px 16px;
  padding-top: calc(12px + env(safe-area-inset-top));
  background: var(--brand);
  color: #fff;
}
.appbar h1 {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 600;
}
.icon-btn {
  background: transparent;
  border: 0;
  color: #fff;
  font-size: 1.3rem;
  line-height: 1;
  padding: 6px 10px;
  border-radius: 8px;
  cursor: pointer;
}
.icon-btn:active { background: rgba(255,255,255,.2); }

main {
  max-width: 640px;
  margin: 0 auto;
  padding: 12px 12px calc(32px + env(safe-area-inset-bottom));
}

/* ---------- card ---------- */
.card {
  background: var(--card);
  border-radius: var(--radius);
  padding: 14px;
  margin-bottom: 12px;
  box-shadow: 0 1px 3px rgba(0,0,0,.06);
}
.card h2 {
  margin: 0 0 10px;
  font-size: 1rem;
  font-weight: 600;
}
.card h3 {
  margin: 16px 0 8px;
  font-size: .95rem;
  font-weight: 600;
}
.hint {
  margin: 8px 0 0;
  font-size: .78rem;
  color: var(--sub);
}

/* ---------- inputs ---------- */
input, select, button {
  font-family: inherit;
  font-size: 1rem;
}
input[type="text"], input[type="date"], input[type="number"], select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: var(--ink);
  min-height: 44px;
}
input:focus, select:focus {
  outline: 2px solid var(--brand);
  outline-offset: -1px;
}
.title-input { font-weight: 600; }
.trip-head { display: grid; gap: 8px; }
.row { display: flex; gap: 8px; align-items: center; }
.row > input { flex: 1; min-width: 0; }
.btn-row { margin-top: 12px; gap: 8px; }
.round-row { justify-content: space-between; margin-bottom: 12px; }
.round-row label { font-size: .9rem; color: var(--sub); white-space: nowrap; }
.round-row select { width: auto; flex: 0 0 auto; }

/* ---------- buttons ---------- */
.btn {
  padding: 10px 14px;
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn.primary { background: var(--brand); border-color: var(--brand); color: #fff; }
.btn.danger { background: #fff; border-color: #f5c6c6; color: var(--danger); }
.btn.block { display: block; width: 100%; margin-top: 8px; }
.btn.small { min-height: 36px; padding: 6px 10px; font-size: .85rem; }

/* ---------- shared view ---------- */
.viewer-badge {
  display: inline-block;
  font-size: .74rem;
  color: var(--brand);
  background: var(--brand-weak);
  border-radius: 999px;
  padding: 3px 10px;
  margin: 0 0 8px;
}
#viewer h2 { margin: 0; }
.view-segment {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 12px;
  margin-bottom: 10px;
}
.view-route {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: .92rem;
  flex-wrap: wrap;
}
.view-meta { font-size: .8rem; color: var(--sub); margin-top: 3px; }
.view-riders { font-size: .82rem; color: var(--sub); margin: 4px 0 6px; }
.view-expense {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
  font-size: .88rem;
  padding: 3px 0;
  border-top: 1px dashed var(--line);
}
.view-expense .payer { font-size: .76rem; color: var(--sub); margin-left: 8px; }
.view-expense .amount { font-variant-numeric: tabular-nums; white-space: nowrap; }

/* ---------- car settings ---------- */
.car-grid {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px 12px;
  align-items: center;
}
.car-grid label { font-size: .9rem; color: var(--sub); white-space: nowrap; }
.unit-input { display: flex; align-items: center; gap: 6px; }
.unit-input input { flex: 1; min-width: 0; }
.unit-input .unit { font-size: .85rem; color: var(--sub); white-space: nowrap; }

/* ---------- members ---------- */
.member-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 10px;
}
.member-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 8px 6px 12px;
  border-radius: 999px;
  background: var(--brand-weak);
  color: var(--brand);
  font-size: .9rem;
}
.member-chip .driver-mark { font-size: .8rem; }
.member-chip button {
  border: 0;
  background: transparent;
  color: var(--brand);
  font-size: 1rem;
  line-height: 1;
  padding: 2px 4px;
  cursor: pointer;
  opacity: .7;
}
.empty {
  color: var(--sub);
  font-size: .88rem;
  padding: 8px 0;
}

/* ---------- segments ---------- */
.segment {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 12px;
  margin-bottom: 10px;
}
.segment-head {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 10px;
}
.segment-no {
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--brand);
  color: #fff;
  font-size: .8rem;
  display: grid;
  place-items: center;
}
.segment-head .arrow { color: var(--sub); flex: 0 0 auto; }
.segment-head input { flex: 1 1 0; min-width: 0; }
.segment-head .del { flex: 0 0 auto; }

.riders { margin-bottom: 10px; }
.riders-label {
  font-size: .8rem;
  color: var(--sub);
  margin-bottom: 6px;
}
.rider-toggles { display: flex; flex-wrap: wrap; gap: 6px; }
.rider-toggle {
  padding: 7px 12px;
  min-height: 38px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--sub);
  font-size: .88rem;
  cursor: pointer;
}
.rider-toggle.on {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

.distance-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  font-size: .82rem;
  color: var(--sub);
}
.distance-row .dist-text { flex: 1; min-width: 0; }
.distance-row .dist-text .known { color: var(--ink); font-weight: 600; }
.distance-row .btn { flex: 0 0 auto; }
.dist-roads { color: var(--sub); font-size: .78rem; }
.avoid-highway {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: .8rem;
  color: var(--sub);
  margin: -4px 0 10px;
  cursor: pointer;
}
.avoid-highway input { width: 16px; height: 16px; flex: 0 0 auto; }
.place-name {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
  font-size: .74rem;
  color: var(--sub);
  padding: 0 2px 6px;
}
.place-pick {
  flex: 0 1 auto;
  min-width: 0;
  max-width: 100%;
  border: 0;
  border-bottom: 1px dashed var(--sub);
  background: transparent;
  color: var(--sub);
  font-size: .74rem;
  font-family: inherit;
  padding: 2px 1px;
  cursor: pointer;
  text-align: left;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.place-pick:active { color: var(--brand); }

.expense {
  display: grid;
  grid-template-columns: 1fr 1fr auto;
  gap: 6px;
  align-items: center;
  margin-bottom: 6px;
}
.expense select, .expense input { min-height: 40px; padding: 8px 10px; font-size: .9rem; }
.expense .del {
  border: 0;
  background: transparent;
  color: var(--sub);
  font-size: 1.1rem;
  padding: 4px 6px;
  cursor: pointer;
}
.expense-payer {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: .82rem;
  color: var(--sub);
}
.expense-payer select { flex: 1; }
.toll-link, .calc-btn {
  display: inline-block;
  font-size: .8rem;
  color: var(--brand);
  background: transparent;
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 5px 8px;
  white-space: nowrap;
  cursor: pointer;
  min-height: 34px;
}
.calc-btn[disabled] { opacity: .45; cursor: default; }
.expense-block {
  border-top: 1px dashed var(--line);
  padding-top: 8px;
  margin-top: 8px;
}
.seg-subtotal {
  text-align: right;
  font-size: .82rem;
  color: var(--sub);
  margin-top: 6px;
}

/* ---------- results ---------- */
.total-box {
  background: var(--brand-weak);
  border-radius: 10px;
  padding: 10px 12px;
  margin-bottom: 12px;
  font-size: .92rem;
}
.total-box .big { font-size: 1.3rem; font-weight: 700; color: var(--brand); }

.balance-row, .transfer-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 8px;
  padding: 9px 0;
  border-bottom: 1px solid var(--line);
  font-size: .92rem;
}
.balance-row:last-child, .transfer-row:last-child { border-bottom: 0; }
.balance-name { font-weight: 600; }
.balance-detail { color: var(--sub); font-size: .78rem; font-weight: normal; }
.amount-plus { color: var(--plus); font-weight: 600; }
.amount-minus { color: var(--minus); font-weight: 600; }
.transfer-row .who { font-weight: 600; }
.transfer-row .amount { font-weight: 700; color: var(--brand); }

.manual-copy { margin-top: 10px; }
.manual-copy textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: var(--ink);
  font-family: inherit;
  font-size: .85rem;
  line-height: 1.5;
  resize: vertical;
}

/* ---------- sheet ---------- */
.sheet { position: fixed; inset: 0; z-index: 50; }
.sheet-backdrop { position: absolute; inset: 0; background: rgba(0,0,0,.4); }
.sheet-body {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  background: var(--card);
  border-radius: 16px 16px 0 0;
  padding: 16px 16px calc(16px + env(safe-area-inset-bottom));
  max-height: 80vh;
  overflow-y: auto;
}
.sheet-body h2 { margin: 0 0 12px; font-size: 1rem; }
.trip-list { margin-bottom: 12px; }
.trip-item {
  display: block;
  width: 100%;
  text-align: left;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  margin-bottom: 6px;
  cursor: pointer;
  font-size: .92rem;
}
.trip-item.active { border-color: var(--brand); background: var(--brand-weak); }
.trip-item .sub { display: block; font-size: .78rem; color: var(--sub); }
.sheet-body .hint { margin: 0 0 8px; }
.sheet-body .row { margin-bottom: 8px; }

/* ---------- toast ---------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: calc(24px + env(safe-area-inset-bottom));
  transform: translateX(-50%);
  background: rgba(26,32,44,.92);
  color: #fff;
  padding: 10px 18px;
  border-radius: 999px;
  font-size: .88rem;
  z-index: 100;
}

.hidden { display: none !important; }
.foot { text-align: center; color: var(--sub); font-size: .75rem; }

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12161c;
    --card: #1b212a;
    --ink: #e6eaf0;
    --sub: #94a3b8;
    --line: #2d3644;
    --brand: #63a4e8;
    --brand-weak: #1e2a38;
    --danger: #f28b82;
    --plus: #68d391;
    --minus: #f28b82;
  }
  .appbar { background: #1b2836; }
  input[type="text"], input[type="date"], input[type="number"], select,
  textarea, .btn, .rider-toggle, .segment, .trip-item { background: #232b36; }
  .btn.primary { background: var(--brand); color: #10151b; }
  .rider-toggle.on { color: #10151b; }
  .btn.danger { background: #232b36; border-color: #533; }
}