:root {
  --bg: #F2F2F7;
  --surface: #FFFFFF;
  --surface-raised: #FFFFFF;
  --ink: #1C1C1E;
  --ink-secondary: #6E6E73;
  --ink-tertiary: #AEAEB2;
  --separator: rgba(60, 60, 67, 0.29);
  --separator-opaque: rgba(60, 60, 67, 0.12);
  --accent: #007AFF;
  --accent-tint: rgba(0, 122, 255, 0.12);
  --accent-contrast: #FFFFFF;
  --debt: #FF3B30;
  --debt-bg: rgba(255, 59, 48, 0.12);
  --paid: #34C759;
  --paid-bg: rgba(52, 199, 89, 0.12);
  --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-2: 0 8px 24px rgba(0, 0, 0, 0.06);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #000000;
    --surface: #1C1C1E;
    --surface-raised: #2C2C2E;
    --ink: #FFFFFF;
    --ink-secondary: #98989D;
    --ink-tertiary: #636366;
    --separator: rgba(84, 84, 88, 0.6);
    --separator-opaque: rgba(84, 84, 88, 0.4);
    --accent: #0A84FF;
    --accent-tint: rgba(10, 132, 255, 0.16);
    --accent-contrast: #FFFFFF;
    --debt: #FF453A;
    --debt-bg: rgba(255, 69, 58, 0.16);
    --paid: #32D74B;
    --paid-bg: rgba(50, 215, 75, 0.16);
    --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-2: 0 8px 24px rgba(0, 0, 0, 0.4);
  }
}
:root[data-theme="dark"] {
  --bg: #000000;
  --surface: #1C1C1E;
  --surface-raised: #2C2C2E;
  --ink: #FFFFFF;
  --ink-secondary: #98989D;
  --ink-tertiary: #636366;
  --separator: rgba(84, 84, 88, 0.6);
  --separator-opaque: rgba(84, 84, 88, 0.4);
  --accent: #0A84FF;
  --accent-tint: rgba(10, 132, 255, 0.16);
  --accent-contrast: #FFFFFF;
  --debt: #FF453A;
  --debt-bg: rgba(255, 69, 58, 0.16);
  --paid: #32D74B;
  --paid-bg: rgba(50, 215, 75, 0.16);
  --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-2: 0 8px 24px rgba(0, 0, 0, 0.4);
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
html, body { background: var(--bg); }
body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  font-size: 15px;
  line-height: 1.4;
}
.page {
  max-width: 640px;
  margin: 0 auto;
  padding: 24px 16px 80px;
}
.page[hidden] { display: none !important; }

/* ---------- Login ---------- */
#loginScreen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.login-card {
  width: 100%;
  max-width: 340px;
  background: var(--surface);
  border-radius: 20px;
  padding: 36px 28px 28px;
  text-align: center;
  box-shadow: var(--shadow-1), var(--shadow-2);
  animation: materialize 0.42s cubic-bezier(.22,1,.36,1) both;
}
@keyframes materialize {
  from { opacity: 0; transform: translateY(10px) scale(0.98); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}
@media (prefers-reduced-motion: reduce) {
  .login-card { animation: none; }
}
.login-card__mark {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  border-radius: 14px;
  background: var(--accent);
  color: var(--accent-contrast);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.01em;
  box-shadow: 0 4px 14px rgba(0, 122, 255, 0.35);
}
.login-card__title {
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0 0 4px;
  color: var(--ink);
}
.login-card__sub {
  font-size: 0.82rem;
  color: var(--ink-secondary);
  margin-bottom: 24px;
}
.login-form { display: flex; flex-direction: column; gap: 10px; }
.text-input {
  font-family: inherit;
  font-size: 0.98rem;
  padding: 13px 15px;
  border-radius: 12px;
  border: none;
  background: var(--bg);
  color: var(--ink);
  outline: none;
  width: 100%;
}
.text-input:focus { box-shadow: 0 0 0 2px var(--accent); }
.login-error {
  font-size: 0.8rem;
  color: var(--debt);
  margin: 4px 0 0;
}
.login-error[hidden] { display: none; }

/* ---------- Masthead ---------- */
.masthead {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  padding-bottom: 20px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}
.masthead h1 {
  font-size: 1.7rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0;
  color: var(--ink);
}
.masthead .sub {
  font-size: 0.85rem;
  color: var(--ink-secondary);
  margin-top: 2px;
}
.masthead__right { display: flex; align-items: center; gap: 10px; padding-top: 2px; }
.masthead .today {
  font-size: 0.78rem;
  color: var(--ink-tertiary);
  white-space: nowrap;
}
.icon-btn {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: none;
  background: var(--surface);
  color: var(--ink-secondary);
  cursor: pointer;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.1s ease-out, background 0.15s ease, color 0.15s ease;
  box-shadow: var(--shadow-1);
}
.icon-btn:active { transform: scale(0.9); }
.icon-btn:hover { background: var(--separator-opaque); }
.logout-btn:hover { color: var(--debt); }

/* ---------- Summary tiles ---------- */
.summary {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 24px;
}
.tile {
  background: var(--surface);
  border-radius: 14px;
  padding: 14px 14px 12px;
  box-shadow: var(--shadow-1);
}
.tile__label {
  font-size: 0.66rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--ink-secondary);
  margin-bottom: 6px;
}
.tile__value {
  font-weight: 700;
  font-size: clamp(1.05rem, 4vw, 1.3rem);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}
.tile--debt .tile__value { color: var(--debt); }
.tile--paid .tile__value { color: var(--paid); }

/* ---------- Toolbar ---------- */
.toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
  padding: 0 4px;
}
.toolbar h2 {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--ink-secondary);
  margin: 0;
}
.btn {
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 12px;
  border: none;
  padding: 10px 16px;
  cursor: pointer;
  transition: transform 0.1s ease-out, filter 0.15s ease, opacity 0.15s ease;
  letter-spacing: -0.005em;
}
.btn:active { transform: scale(0.97); }
.btn-accent { background: var(--accent); color: var(--accent-contrast); }
.btn-accent:hover { filter: brightness(1.05); }
.btn-ghost { background: var(--accent-tint); color: var(--accent); }
.btn-ghost:hover { filter: brightness(1.05); }
.btn-sm { padding: 7px 12px; font-size: 0.82rem; border-radius: 10px; }
.btn-block { width: 100%; padding: 14px; font-size: 0.98rem; }
.btn[disabled] { opacity: 0.4; cursor: not-allowed; }

/* ---------- Add client form ---------- */
.add-form {
  background: var(--surface);
  border-radius: 14px;
  padding: 16px;
  margin-bottom: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  box-shadow: var(--shadow-1);
  animation: materialize 0.3s cubic-bezier(.22,1,.36,1) both;
}
.add-form[hidden] { display: none; }
.field-row { display: flex; gap: 10px; flex-wrap: wrap; }
.field { flex: 1; min-width: 140px; display: flex; flex-direction: column; gap: 5px; }
.field label {
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--ink-secondary);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.field input {
  font-family: inherit;
  font-size: 0.95rem;
  padding: 10px 12px;
  border-radius: 10px;
  border: none;
  background: var(--bg);
  color: var(--ink);
  outline: none;
}
.field input:focus { box-shadow: 0 0 0 2px var(--accent); }
.add-form__actions { display: flex; gap: 8px; justify-content: flex-end; }

/* ---------- Ledger list ---------- */
.ledger { display: flex; flex-direction: column; gap: 10px; }
.row {
  background: var(--surface);
  border-radius: 14px;
  overflow: hidden;
  box-shadow: var(--shadow-1);
}
.row__head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  cursor: pointer;
  transition: transform 0.1s ease-out;
}
.row__head:active { background: var(--separator-opaque); transform: scale(0.99); }
.row__name-wrap { flex: 1; min-width: 0; }
.row__name { font-weight: 600; font-size: 1rem; letter-spacing: -0.01em; }
.row__phone { font-size: 0.8rem; color: var(--ink-secondary); margin-top: 1px; }
.pill {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  padding: 4px 9px;
  border-radius: 999px;
  white-space: nowrap;
}
.pill--debt { color: var(--debt); background: var(--debt-bg); }
.pill--paid { color: var(--paid); background: var(--paid-bg); }
.row__balance {
  font-weight: 700;
  font-size: 1.05rem;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  letter-spacing: -0.01em;
}
.row__balance--debt { color: var(--debt); }
.row__balance--paid { color: var(--paid); }
.row__chevron {
  color: var(--ink-tertiary);
  font-size: 0.78rem;
  transition: transform 0.18s cubic-bezier(.22,1,.36,1);
  flex-shrink: 0;
}
.row.is-open .row__chevron { transform: rotate(90deg); }

.row__detail-wrap {
  display: grid;
  grid-template-rows: 0fr;
  opacity: 0;
  transition: grid-template-rows 0.32s cubic-bezier(.22,1,.36,1), opacity 0.2s ease;
}
.row__detail-wrap.is-open {
  grid-template-rows: 1fr;
  opacity: 1;
}
.row__detail {
  min-height: 0;
  overflow: hidden;
  border-top: 1px solid var(--separator-opaque);
  padding: 14px 16px 16px;
}
@media (prefers-reduced-motion: reduce) {
  .row__detail-wrap { transition: opacity 0.15s ease; }
  .row__detail-wrap:not(.is-open) { grid-template-rows: 0fr; }
}

.history { display: flex; flex-direction: column; margin-bottom: 12px; max-height: 240px; overflow-y: auto; }
.history__empty { font-size: 0.85rem; color: var(--ink-tertiary); padding: 6px 0; }
.move {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 0;
  border-bottom: 1px solid var(--separator-opaque);
  font-size: 0.86rem;
}
.move:last-child { border-bottom: none; }
.move__date { font-size: 0.74rem; color: var(--ink-tertiary); white-space: nowrap; font-variant-numeric: tabular-nums; }
.move__concept { flex: 1; min-width: 0; color: var(--ink-secondary); overflow-wrap: break-word; }
.move__amount { font-weight: 600; font-variant-numeric: tabular-nums; white-space: nowrap; }
.move__amount--cargo { color: var(--debt); }
.move__amount--abono { color: var(--paid); }
.move__actions { display: flex; gap: 2px; flex-shrink: 0; }
.move__actions .icon-btn { width: 24px; height: 24px; font-size: 0.7rem; box-shadow: none; background: transparent; }
.move__actions .icon-btn:hover { background: var(--separator-opaque); }

.move-edit-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  align-items: center;
  padding: 8px 0;
  border-bottom: 1px solid var(--separator-opaque);
  animation: materialize 0.22s cubic-bezier(.22,1,.36,1) both;
}
.move-edit-row input {
  font-family: inherit;
  font-size: 0.85rem;
  padding: 7px 9px;
  border-radius: 8px;
  border: none;
  background: var(--bg);
  color: var(--ink);
  outline: none;
}
.move-edit-row input:focus { box-shadow: 0 0 0 2px var(--accent); }
.move-edit-row input[type="number"] { width: 84px; }
.move-edit-row input[type="date"] { width: 130px; }
.move-edit-row input[type="text"] { flex: 1; min-width: 100px; }

.detail-actions { display: flex; flex-direction: column; gap: 10px; }
.amount-row { display: flex; gap: 8px; flex-wrap: wrap; }
.amount-row input[type="number"] { width: 90px; }
.amount-row input[type="text"] { flex: 1; min-width: 120px; }
.amount-row input {
  font-family: inherit;
  font-size: 0.9rem;
  padding: 9px 10px;
  border-radius: 10px;
  border: none;
  background: var(--bg);
  color: var(--ink);
  outline: none;
}
.amount-row input:focus { box-shadow: 0 0 0 2px var(--accent); }
.amount-row .btn-row { display: flex; gap: 6px; }
.wa-row { display: flex; justify-content: space-between; align-items: center; gap: 10px; padding-top: 12px; border-top: 1px solid var(--separator-opaque); flex-wrap: wrap; }
.wa-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  background: #25D366;
  color: #FFFFFF;
  font-weight: 600;
}
.text-link { font-size: 0.78rem; color: var(--ink-tertiary); background: none; border: none; cursor: pointer; padding: 0; }
.text-link:hover { color: var(--accent); }
.phone-block { margin-top: -2px; }
.phone-edit-row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; animation: materialize 0.26s cubic-bezier(.22,1,.36,1) both; }
.phone-edit-row input {
  flex: 1;
  min-width: 140px;
  font-family: inherit;
  font-size: 0.9rem;
  padding: 9px 10px;
  border-radius: 10px;
  border: none;
  background: var(--bg);
  color: var(--ink);
  outline: none;
}
.phone-edit-row input:focus { box-shadow: 0 0 0 2px var(--accent); }
@media (prefers-reduced-motion: reduce) {
  .add-form, .phone-edit-row, .move-edit-row { animation: none; }
}

/* ---------- Empty state ---------- */
.empty {
  text-align: center;
  padding: 48px 20px;
  border-radius: 16px;
  background: var(--surface);
  box-shadow: var(--shadow-1);
}
.empty__icon { font-size: 2rem; margin-bottom: 10px; }
.empty h3 { margin: 0 0 6px; font-size: 1.05rem; font-weight: 700; letter-spacing: -0.01em; }
.empty p { margin: 0 0 16px; color: var(--ink-secondary); font-size: 0.88rem; max-width: 40ch; margin-inline: auto; }

.archived-toggle { text-align: center; margin-top: 16px; }
.archived-toggle button { background: none; border: none; color: var(--ink-tertiary); font-size: 0.8rem; cursor: pointer; }
.archived-toggle button:hover { color: var(--accent); }

footer.note {
  text-align: center;
  font-size: 0.72rem;
  color: var(--ink-tertiary);
  margin-top: 32px;
}

.unavailable {
  padding: 40px 20px;
  text-align: center;
  color: var(--ink-secondary);
}

@media (max-width: 460px) {
  .summary { grid-template-columns: 1fr 1fr; }
  .tile:nth-child(3) { grid-column: span 2; }
}

/* ---------- Toast ---------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: 24px;
  transform: translate(-50%, 12px);
  background: var(--ink);
  color: var(--bg);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 12px 18px;
  border-radius: 12px;
  box-shadow: var(--shadow-2);
  opacity: 0;
  transition: opacity 0.24s cubic-bezier(.22,1,.36,1), transform 0.24s cubic-bezier(.22,1,.36,1);
  z-index: 1000;
  max-width: 88vw;
  text-align: center;
}
.toast.is-visible { opacity: 1; transform: translate(-50%, 0); }
@media (prefers-reduced-motion: reduce) {
  .toast { transition: opacity 0.15s ease; transform: translate(-50%, 0) !important; }
}