/* app.css — all styles for Lesson Ledger. Phone-first, no framework, no build.
   Rules of the house: single column, tap targets >= 44px, readable at 360px,
   16px form controls (so iOS never zooms on focus), and nothing fussy. */

:root {
  color-scheme: light dark;

  --bg: #f4f5f7;
  --surface: #ffffff;
  --surface-2: #eef0f4;
  --ink: #16181d;
  --ink-soft: #5c626e;
  --line: #d9dce3;
  --accent: #1f5fd0;
  --accent-ink: #ffffff;
  --owed: #a8341f;
  --credit: #1c6b45;
  --warn-bg: #fdf3d3;
  --warn-ink: #6b4e00;

  /* Traffic light (DESIGN.md): green starts, red stops, blue creates. */
  --go: #12813c;
  --go-ink: #ffffff;
  --stop: #c22e22;
  --stop-ink: #ffffff;
  --make: var(--accent);
  --make-ink: var(--accent-ink);

  --radius: 12px;
  --tap: 44px;
  --gap: 0.75rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161a;
    --surface: #1d2026;
    --surface-2: #24282f;
    --ink: #f0f1f4;
    --ink-soft: #a5abb8;
    --line: #333844;
    --accent: #6b9dfa;
    --accent-ink: #0f1115;
    --owed: #ff9c85;
    --credit: #79dba8;
    --warn-bg: #3d3213;
    --warn-ink: #f3e0a6;

    --go: #35c163;
    --go-ink: #06140b;
    --stop: #ff6a5c;
    --stop-ink: #1b0b09;
    --make: var(--accent);
    --make-ink: var(--accent-ink);
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 1rem 1rem 3rem;
  background: var(--bg);
  color: var(--ink);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 1rem;
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
}

#app {
  display: block;
  max-width: 32rem;
  margin: 0 auto;
}

/* --- typography ---------------------------------------------------------- */

h1,
h2 {
  margin: 0;
  line-height: 1.25;
}

.screen-head {
  margin-bottom: var(--gap);
}

.screen-title {
  font-size: 1.5rem;
  overflow-wrap: anywhere;
}

.back {
  display: inline-flex;
  align-items: center;
  min-height: var(--tap);
  color: var(--accent);
  font-weight: 600;
  text-decoration: none;
}

.hint {
  margin: 0.5rem 0 0;
  color: var(--ink-soft);
  font-size: 0.875rem;
}

.badge {
  display: inline-block;
  margin-left: 0.5rem;
  padding: 0.1rem 0.5rem;
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--ink-soft);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  vertical-align: middle;
}

.alert {
  margin: 0 0 var(--gap);
  padding: 0.75rem;
  border-radius: var(--radius);
  background: var(--warn-bg);
  color: var(--warn-ink);
  font-size: 0.9375rem;
}

/* --- summary strip ------------------------------------------------------- */

.summary {
  margin-bottom: var(--gap);
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.summary-label {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.summary-value {
  margin: 0.15rem 0 0;
  font-size: 2rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.summary-meta {
  margin: 0.25rem 0 0;
  color: var(--ink-soft);
  font-size: 0.875rem;
}

/* --- money --------------------------------------------------------------- */

.amount {
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  white-space: nowrap;
}

.amount-owed {
  color: var(--owed);
}

.amount-credit {
  color: var(--credit);
}

.amount-settled {
  color: var(--ink-soft);
}

/* --- buttons ------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: var(--tap);
  padding: 0.5rem 1rem;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font: inherit;
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
}

/* Primaries: full-width, colour-coded, at most two per screen. */
.btn-green,
.btn-red,
.btn-blue {
  display: flex;
  width: 100%;
  margin-bottom: var(--gap);
  border-color: transparent;
}

.btn-green {
  background: var(--go);
  color: var(--go-ink);
}

.btn-red {
  background: var(--stop);
  color: var(--stop-ink);
}

.btn-blue {
  background: var(--make);
  color: var(--make-ink);
}

/* The big pair — the two taps the whole app is built around. */
.btn-big {
  min-height: 3.5rem;
  font-size: 1.1875rem;
  letter-spacing: 0.01em;
}

/* Secondaries: small, grey, outlined, always below the primaries. */
.btn-small {
  flex: 0 1 auto;
  min-height: var(--tap);
  padding: 0.4rem 0.9rem;
  font-size: 0.9375rem;
  font-weight: 600;
}

.btn-outline {
  border-color: var(--line);
  background: var(--surface);
  color: var(--ink-soft);
}

/* Destructive, and deliberately quiet: red belongs to Finish lesson alone. */
.btn-quiet-danger {
  color: var(--ink-soft);
}

.btn-quiet-danger:hover {
  border-color: var(--owed);
  color: var(--owed);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

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

.actions-secondary {
  margin-top: 0.25rem;
  margin-bottom: var(--gap);
}

.screen-foot {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1.25rem;
}

.screen-foot .btn-green,
.screen-foot .btn-red,
.screen-foot .btn-blue {
  margin-bottom: 0;
}

.screen-foot-quiet {
  justify-content: center;
  margin-top: 2rem;
}

.quiet-link {
  min-height: var(--tap);
  display: inline-flex;
  align-items: center;
  color: var(--ink-soft);
  font-size: 0.875rem;
  text-decoration: underline;
}

/* A link that is really a button (the rate line's "change"). */
.link-button {
  min-height: 1.5rem;
  padding: 0;
  border: 0;
  background: none;
  color: var(--accent);
  font: inherit;
  font-size: 0.875rem;
  text-decoration: underline;
  cursor: pointer;
}

/* --- home: hourly-rate setup --------------------------------------------- */

.rate-card {
  border-color: var(--accent);
}

.rate-form .btn {
  width: 100%;
}

.rate-line {
  display: flex;
  gap: 0.5rem;
  align-items: baseline;
  margin: 0 0 var(--gap);
  color: var(--ink-soft);
  font-size: 0.875rem;
}

/* Home's gentle nudge towards Settings while the invoice details are missing.
   Quieter than the rate card: this one does not block anything. */
.setup-card {
  background: var(--surface-2);
}

/* The backup reminder: one quiet line under the two big buttons. No panel, no
   colour of its own, nothing that could be mistaken for a third primary. */
.nudge {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.75rem;
  align-items: baseline;
  margin: 0 0 var(--gap);
  color: var(--ink-soft);
  font-size: 0.875rem;
}

.nudge-text {
  flex: 1 1 auto;
}

.nudge-dismiss {
  color: var(--ink-soft);
}

/* The reminder's own answer — "No backup was made this time." — sits directly
   under the line that offered it, closer to it than to anything else. */
.nudge-status {
  margin-top: calc(var(--gap) * -0.5);
}

/* A link-button while it is working: Home's "Back up" disables itself for as
   long as the share sheet is open, and must stop looking tappable. */
.link-button[disabled] {
  color: var(--ink-soft);
  text-decoration: none;
  cursor: default;
}

/* --- undo notice ---------------------------------------------------------- */

.undo-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: var(--gap);
  padding: 0.625rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface-2);
}

.undo-text {
  flex: 1 1 auto;
  font-size: 0.9375rem;
  font-weight: 600;
}

/* --- running-lesson banner (home) ---------------------------------------- */

.banner {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  min-height: var(--tap);
  margin-bottom: var(--gap);
  padding: 0.75rem 1rem;
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  background: var(--warn-bg);
  color: var(--warn-ink);
  text-decoration: none;
}

.banner-body {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
}

.banner-title {
  font-weight: 700;
  overflow-wrap: anywhere;
}

.banner-meta {
  font-size: 0.875rem;
}

/* --- active lesson ------------------------------------------------------- */

.stopwatch {
  margin: 0.15rem 0 0;
  font-size: 2.75rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  line-height: 1.1;
}

.guard {
  border-color: var(--owed);
}

.preview {
  margin: 0;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

.inline-link {
  color: var(--accent);
  font-weight: 600;
}

/* --- panels -------------------------------------------------------------- */

.panel {
  margin-bottom: var(--gap);
  padding: 0.875rem 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.panel-title {
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
}

.panel-muted {
  background: var(--surface-2);
}

.panel-summary {
  display: flex;
  align-items: center;
  min-height: var(--tap);
  color: var(--ink-soft);
  font-size: 0.9375rem;
  font-weight: 600;
  cursor: pointer;
}

/* --- customer list ------------------------------------------------------- */

.list {
  margin: 0.25rem 0 0;
  padding: 0;
  list-style: none;
}

.list-item + .list-item {
  border-top: 1px solid var(--line);
}

.row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-height: 3rem;
  padding: 0.5rem 0;
  color: inherit;
  text-decoration: none;
}

.row-name {
  flex: 1 1 auto;
  font-weight: 600;
  overflow-wrap: anywhere;
}

.row-chevron {
  color: var(--ink-soft);
  font-size: 1.25rem;
}

.empty {
  padding: 1rem 0 0.5rem;
  text-align: center;
}

.empty-title {
  margin: 0;
  font-weight: 700;
}

.empty-body {
  margin: 0.25rem 0 0;
  color: var(--ink-soft);
  font-size: 0.9375rem;
}

/* --- ledgers ------------------------------------------------------------- */

.ledger {
  margin: 0.25rem 0 0;
  padding: 0;
  list-style: none;
}

.entry {
  padding: 0.625rem 0;
}

.entry + .entry {
  border-top: 1px solid var(--line);
}

.entry-link {
  display: block;
  min-height: var(--tap);
  padding: 0.125rem 0;
  color: inherit;
  text-decoration: none;
}

.entry-link:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.entry-top {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}

.entry-top .row-chevron {
  margin-left: 0.25rem;
}

.entry-date {
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  white-space: nowrap;
}

.entry-name {
  flex: 1 1 auto;
  overflow-wrap: anywhere;
}

.entry-top .amount {
  margin-left: auto;
}

.entry-sub {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.75rem;
  color: var(--ink-soft);
  font-size: 0.875rem;
}

.entry-running {
  margin-left: auto;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.entry-actions {
  display: flex;
  justify-content: flex-end;
  margin-top: 0.375rem;
}

/* --- contact details ----------------------------------------------------- */

.contact {
  display: grid;
  grid-template-columns: minmax(4.5rem, auto) 1fr;
  gap: 0.35rem 0.75rem;
  margin: 0.5rem 0 0;
}

.contact dt {
  color: var(--ink-soft);
  font-size: 0.875rem;
}

.contact dd {
  margin: 0;
  overflow-wrap: anywhere;
  white-space: pre-line;
}

.contact a {
  color: var(--accent);
}

/* --- invoices ------------------------------------------------------------ */

/* Ticking lessons onto an invoice: the whole row is one tap target. */
.pick-list {
  margin: 0.25rem 0 0;
  padding: 0;
  list-style: none;
}

.pick + .pick {
  border-top: 1px solid var(--line);
}

.pick-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-height: var(--tap);
  padding: 0.5rem 0;
  cursor: pointer;
}

.pick-body {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
}

.pick-top {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}

.pick-top .amount {
  margin-left: auto;
}

.pick-sub {
  color: var(--ink-soft);
  font-size: 0.875rem;
}

/* The preview: the invoice itself, as the customer will read it. */
.invoice-doc {
  background: var(--surface);
}

.doc-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.5rem;
  margin-bottom: var(--gap);
}

.doc-heading {
  flex: 1 1 auto;
  font-size: 1.25rem;
}

.doc-number {
  margin-left: auto;
  text-align: right;
}

.doc-party {
  margin-bottom: var(--gap);
}

.doc-label {
  margin: 0 0 0.15rem;
  color: var(--ink-soft);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.doc-line {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.875rem;
  overflow-wrap: anywhere;
}

.doc-strong {
  color: var(--ink);
  font-size: 1rem;
  font-weight: 700;
}

/* Wide content scrolls inside its own box — the page never scrolls sideways. */
.table-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.invoice-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8125rem;
  white-space: nowrap;
}

.invoice-table th,
.invoice-table td {
  padding: 0.4rem 0.5rem 0.4rem 0;
  text-align: left;
  vertical-align: top;
}

.invoice-table th {
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.invoice-table tbody tr + tr td {
  border-top: 1px solid var(--line);
}

.invoice-table .num {
  text-align: right;
  font-variant-numeric: tabular-nums;
  padding-right: 0;
  padding-left: 0.75rem;
}

.invoice-totals {
  margin-top: var(--gap);
}

.invoice-balance {
  padding-top: 0.5rem;
  border-top: 1px solid var(--line);
}

.total-row {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  padding: 0.15rem 0;
  color: var(--ink-soft);
  font-size: 0.9375rem;
}

.total-label {
  flex: 1 1 auto;
}

.total-value {
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.total-row-main {
  color: var(--ink);
  font-size: 1.0625rem;
  font-weight: 700;
}

.total-note {
  margin: 0.35rem 0 0;
  color: var(--ink-soft);
  font-size: 0.875rem;
}

.invoice-pay {
  margin-top: var(--gap);
  padding: 0.75rem;
  border-radius: var(--radius);
  background: var(--surface-2);
}

/* --- forms --------------------------------------------------------------- */

.field {
  margin-bottom: 1rem;
}

/* The whole sponsor form, opened inside the "Who pays?" step. It is a second
   form sitting under the pick list, so it is ruled off from it — without the
   line the "Name of the organisation" box reads as one more thing to fill in
   for the customer being added, rather than the start of the organisation. */
.sponsor-add {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}

/* Present but deliberately understated — e.g. the per-customer rate box, which
   is prefilled and should only be touched on purpose. */
.field-minor .label {
  color: var(--ink-soft);
  font-size: 0.875rem;
  font-weight: 600;
}

.field-minor .input {
  background: var(--surface-2);
}

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

.req {
  color: var(--owed);
}

.input {
  display: block;
  width: 100%;
  min-height: var(--tap);
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--ink);
  font: inherit;
  font-size: 1rem; /* 16px: stops iOS zooming on focus */
}

textarea.input {
  min-height: 3.5rem;
  resize: vertical;
}

/* A checkbox and its words as one 44px tap target (the GST toggle). */
.check-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-height: var(--tap);
  cursor: pointer;
}

.check {
  width: 1.375rem;
  height: 1.375rem;
  margin: 0;
  flex: 0 0 auto;
  accent-color: var(--accent);
}

.check-label {
  font-weight: 600;
}

.input:focus-visible,
.check:focus-visible,
.btn:focus-visible,
.row:focus-visible,
.back:focus-visible,
.panel-summary:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.input[aria-invalid="true"] {
  border-color: var(--owed);
}

.field-error,
.form-error {
  margin: 0.35rem 0 0;
  color: var(--owed);
  font-size: 0.875rem;
  font-weight: 600;
}

.form-error {
  margin: 0 0 var(--gap);
}