/* ==========================================================================
   Tokens
   ========================================================================== */
:root {
  /* Palette — light */
  --color-bg: #f7f7f8;
  --color-surface: #ffffff;
  --color-surface-2: #fafafa;
  --color-border: #e5e7eb;
  --color-border-strong: #d1d5db;
  --color-text: #0f172a;
  --color-text-muted: #64748b;
  --color-text-subtle: #94a3b8;
  --color-accent: #4338ca;
  --color-accent-hover: #3730a3;
  --color-accent-contrast: #ffffff;
  --color-danger: #dc2626;

  /* Typography */
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --fs-xs: 0.75rem;
  --fs-sm: 0.8125rem;
  --fs-base: 0.9375rem;
  --fs-md: 1rem;
  --fs-lg: 1.25rem;
  --fs-xl: 1.75rem;
  --fs-2xl: 2.25rem;
  --lh-tight: 1.2;
  --lh-normal: 1.5;

  /* Spacing */
  --sp-1: 0.25rem;
  --sp-2: 0.5rem;
  --sp-3: 0.75rem;
  --sp-4: 1rem;
  --sp-5: 1.25rem;
  --sp-6: 1.5rem;
  --sp-8: 2rem;
  --sp-10: 2.5rem;
  --sp-12: 3rem;

  /* Radii / shadows */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.06);
  --shadow-lg: 0 12px 32px rgba(15, 23, 42, 0.08);

  /* Layout */
  --toolbar-h: 56px;
  --bp-md: 900px;
}

[data-theme="dark"] {
  --color-bg: #0b0d10;
  --color-surface: #14171c;
  --color-surface-2: #181c22;
  --color-border: #262b33;
  --color-border-strong: #363c46;
  --color-text: #e6e8ec;
  --color-text-muted: #9aa3af;
  --color-text-subtle: #6b7380;
  --color-accent: #8b8cff;
  --color-accent-hover: #a5a6ff;
  --color-accent-contrast: #0b0d10;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
}

/* ==========================================================================
   Reset + base
   ========================================================================== */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--font-sans);
  font-size: var(--fs-base);
  line-height: var(--lh-normal);
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
h1, h2, h3, p { margin: 0; }
button { font: inherit; color: inherit; }

/* ==========================================================================
   Toolbar
   ========================================================================== */
.toolbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  min-height: var(--toolbar-h);
  padding: var(--sp-2) var(--sp-4);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}
.toolbar__brand {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  font-weight: 600;
  letter-spacing: -0.01em;
}
.toolbar__logo {
  display: inline-block;
  width: 20px;
  height: 20px;
  border-radius: 5px;
  background: linear-gradient(135deg, var(--color-accent), var(--color-text));
}
.toolbar__name { font-size: var(--fs-md); }
.toolbar__actions {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
}
@media (max-width: 560px) {
  html, body { max-width: 100vw; }
  .toolbar {
    flex-direction: column;
    align-items: stretch;
    gap: var(--sp-2);
    padding: var(--sp-2) var(--sp-3);
  }
  .toolbar__actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-areas:
      "currency theme"
      "new download";
    gap: var(--sp-2);
    width: 100%;
    min-width: 0;
  }
  .toolbar__actions > * { min-width: 0; width: 100%; }
  .toolbar__actions .select { grid-area: currency; }
  #theme-toggle { grid-area: theme; }
  #reset { grid-area: new; }
  #download { grid-area: download; }
  .select__label { display: none; }
  .select { padding: 0 var(--sp-2); }
  .btn { padding: 0 var(--sp-2); white-space: nowrap; }
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  height: 36px;
  padding: 0 var(--sp-4);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  font-size: var(--fs-sm);
  font-weight: 500;
  cursor: pointer;
  transition: background-color 120ms ease, border-color 120ms ease, color 120ms ease;
  background: transparent;
}
.btn--primary {
  background: var(--color-accent);
  color: var(--color-accent-contrast);
}
.btn--primary:hover { background: var(--color-accent-hover); }
.btn--ghost {
  border-color: var(--color-border);
  background: var(--color-surface);
}
.btn--ghost:hover { border-color: var(--color-border-strong); background: var(--color-surface-2); }
.btn--subtle {
  color: var(--color-accent);
  padding: 0 var(--sp-2);
  height: 28px;
}
.btn--subtle:hover { color: var(--color-accent-hover); }
.btn__icon { width: 16px; height: 16px; display: inline-block; }
.btn__icon[data-icon="sun"]::before {
  content: "";
  display: block;
  width: 14px; height: 14px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: 0 0 0 2px var(--color-surface), 0 0 0 3px currentColor;
  margin: 1px;
}
[data-theme="dark"] .btn__icon[data-icon="sun"]::before {
  background: transparent;
  box-shadow: inset 3px -3px 0 0 currentColor;
}

/* ==========================================================================
   Select (styled wrap)
   ========================================================================== */
.select {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  height: 36px;
  padding: 0 var(--sp-3);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  border-radius: var(--radius-md);
  font-size: var(--fs-sm);
}
.select__label { color: var(--color-text-muted); }
.select__input {
  border: 0;
  background: transparent;
  color: inherit;
  font: inherit;
  outline: none;
  cursor: pointer;
}

/* ==========================================================================
   Layout
   ========================================================================== */
.layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-4);
  padding: var(--sp-4);
  max-width: 1400px;
  margin: 0 auto;
}
@media (min-width: 560px) {
  .layout { gap: var(--sp-6); padding: var(--sp-6); }
}
@media (min-width: 900px) {
  .layout { grid-template-columns: minmax(380px, 460px) 1fr; gap: var(--sp-8); padding: var(--sp-8); }
}
.editor__section { min-width: 0; }

/* ==========================================================================
   Editor
   ========================================================================== */
.editor {
  display: flex;
  flex-direction: column;
  gap: var(--sp-6);
}
.editor__section {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--sp-5);
  box-shadow: var(--shadow-sm);
}
.editor__section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--sp-3);
}
.editor__heading {
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: var(--sp-3);
}
.editor__section-head .editor__heading { margin-bottom: 0; }

.field { display: flex; flex-direction: column; gap: var(--sp-1); margin-bottom: var(--sp-3); }
.field:last-child { margin-bottom: 0; }
.field__label {
  font-size: var(--fs-xs);
  color: var(--color-text-muted);
  font-weight: 500;
}
.field__input {
  width: 100%;
  height: 36px;
  padding: 0 var(--sp-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface-2);
  color: var(--color-text);
  font: inherit;
  outline: none;
  transition: border-color 120ms, box-shadow 120ms;
}
.field__input--area { height: auto; padding: var(--sp-2) var(--sp-3); resize: vertical; }
.field__input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 20%, transparent);
}
.check {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  margin-top: var(--sp-3);
  font-size: var(--fs-sm);
  color: var(--color-text-muted);
  cursor: pointer;
  user-select: none;
}
.check__input {
  width: 16px; height: 16px;
  accent-color: var(--color-accent);
  cursor: pointer;
  margin: 0;
}
.field-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--sp-3);
}
.field-row .field { margin-bottom: 0; }

/* Items */
.items-head {
  display: grid;
  grid-template-columns: 1fr 64px 80px 80px 28px;
  gap: var(--sp-2);
  padding: 0 var(--sp-1);
  margin-top: var(--sp-3);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-subtle);
}
.items-head__num { text-align: right; }
.items { display: flex; flex-direction: column; gap: var(--sp-2); margin-top: var(--sp-2); }
.item {
  display: grid;
  grid-template-columns: 1fr 64px 80px 80px 28px;
  gap: var(--sp-2);
  align-items: center;
}
.item__desc, .item__num { min-width: 0; }
@media (max-width: 560px) {
  .items-head { display: none; }
  .item {
    grid-template-columns: 1fr 1fr 1fr 28px;
    grid-template-areas:
      "desc desc desc remove"
      "qty rate amount amount";
    row-gap: var(--sp-2);
  }
  .item__desc { grid-area: desc; }
  .item > [data-field="quantity"] { grid-area: qty; }
  .item > [data-field="rate"] { grid-area: rate; }
  .item__amount { grid-area: amount; }
  .item__remove { grid-area: remove; }
}
.item__num { text-align: right; font-variant-numeric: tabular-nums; }
.item__amount {
  text-align: right;
  font-variant-numeric: tabular-nums;
  color: var(--color-text-muted);
  font-size: var(--fs-sm);
}
.item__remove {
  width: 28px; height: 28px;
  border: 1px solid var(--color-border);
  background: var(--color-surface-2);
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--color-text-subtle);
  font-size: 16px;
  line-height: 1;
  padding: 0;
}
.item__remove:hover { color: var(--color-danger); border-color: var(--color-danger); }

/* ==========================================================================
   Preview
   ========================================================================== */
.preview-wrap {
  display: flex;
  justify-content: center;
  align-items: flex-start;
}
.invoice {
  position: relative;
  width: 100%;
  max-width: 800px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: var(--sp-12) var(--sp-10) var(--sp-10);
  color: var(--color-text);
  overflow: hidden;
}
@media (max-width: 560px) {
  .invoice { padding: var(--sp-8) var(--sp-5) var(--sp-6); }
  .invoice__meta { grid-template-columns: 1fr; gap: var(--sp-5); }
  .invoice__dates { gap: var(--sp-6); }
  .invoice__from { text-align: left; }
  .invoice__th, .invoice__td { padding: var(--sp-2); font-size: var(--fs-xs); }
  .invoice__totals { width: 100%; }
}
.invoice::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--color-accent);
}
.invoice__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--sp-6);
  margin-bottom: var(--sp-10);
  flex-wrap: wrap;
}
.invoice__eyebrow {
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--sp-2);
}
.invoice__title {
  font-size: var(--fs-2xl);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: var(--lh-tight);
}
.invoice__number {
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: var(--fs-sm);
  margin-top: var(--sp-2);
}
.invoice__from { text-align: right; font-size: var(--fs-sm); color: var(--color-text-muted); }
.invoice__from .invoice__strong { color: var(--color-text); }

.invoice__meta {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: var(--sp-8);
  margin-bottom: var(--sp-8);
  padding-bottom: var(--sp-6);
  border-bottom: 1px solid var(--color-border);
}
.invoice__dates { display: flex; gap: var(--sp-8); }
.invoice__label {
  font-size: var(--fs-xs);
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-text-subtle);
  margin-bottom: var(--sp-2);
}
.invoice__strong { font-weight: 600; color: var(--color-text); }
.invoice__multiline { white-space: pre-line; color: var(--color-text-muted); font-size: var(--fs-sm); }

.invoice__table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--sp-6);
}
.invoice__th {
  text-align: left;
  font-size: var(--fs-xs);
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-text-subtle);
  padding: var(--sp-2) var(--sp-3);
  border-bottom: 1px solid var(--color-border);
}
.invoice__th--num { text-align: right; }
.invoice__td {
  padding: var(--sp-3);
  border-bottom: 1px solid var(--color-border);
  font-size: var(--fs-sm);
}
.invoice__td--num { text-align: right; font-variant-numeric: tabular-nums; }
.invoice__td--desc { color: var(--color-text); }

.invoice__totals {
  margin-left: auto;
  width: min(320px, 100%);
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}
.invoice__total-row {
  display: flex;
  justify-content: space-between;
  font-size: var(--fs-sm);
  color: var(--color-text-muted);
  font-variant-numeric: tabular-nums;
}
.invoice__total-row--grand {
  padding-top: var(--sp-3);
  margin-top: var(--sp-3);
  border-top: 2px solid var(--color-text);
  font-size: var(--fs-lg);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--color-text);
}
.invoice__total-row[hidden] { display: none; }

.invoice__notes {
  margin-top: var(--sp-10);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--color-border);
}
.invoice__notes[hidden] { display: none; }

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-3);
  padding: var(--sp-6) var(--sp-4);
  font-size: var(--fs-sm);
  color: var(--color-text-muted);
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}
.footer__link {
  background: none;
  border: 0;
  padding: 0;
  font: inherit;
  color: var(--color-text);
  cursor: pointer;
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.footer__link:hover { border-bottom-color: var(--color-text); }
.footer__sep { color: var(--color-text-subtle); }
.footer__muted { color: var(--color-text-muted); }
.footer__muted .footer__link { color: var(--color-text); }

/* ==========================================================================
   Modal
   ========================================================================== */
.modal[hidden] { display: none; }
.modal {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--sp-4);
}
.modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(15, 23, 42, 0.5);
  backdrop-filter: blur(2px);
}
[data-theme="dark"] .modal__backdrop { background: rgba(0, 0, 0, 0.6); }
.modal__dialog {
  position: relative;
  width: 100%;
  max-width: 520px;
  max-height: calc(100vh - var(--sp-8));
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.modal__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  padding: var(--sp-5);
  border-bottom: 1px solid var(--color-border);
}
.modal__title-wrap {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  min-width: 0;
}
.modal__icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--color-accent), var(--color-text));
  flex: 0 0 auto;
}
.modal__title { font-size: var(--fs-md); font-weight: 600; letter-spacing: -0.01em; }
.modal__subtitle { font-size: var(--fs-sm); color: var(--color-text-muted); }
.modal__close {
  width: 32px;
  height: 32px;
  border: 0;
  background: transparent;
  border-radius: var(--radius-sm);
  font-size: 22px;
  line-height: 1;
  color: var(--color-text-muted);
  cursor: pointer;
}
.modal__close:hover { background: var(--color-surface-2); color: var(--color-text); }
.modal__body { padding: var(--sp-5); overflow-y: auto; }
.modal__p { font-size: var(--fs-sm); color: var(--color-text-muted); margin-bottom: var(--sp-4); }
.modal__p code {
  font-family: var(--font-mono);
  font-size: 0.8em;
  padding: 1px 5px;
  border-radius: 4px;
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
}
.modal__section {
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-subtle);
  margin: var(--sp-5) 0 var(--sp-2);
}
.modal__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--sp-3);
  flex-wrap: wrap;
}
.modal__link {
  color: var(--color-text);
  text-decoration: none;
  border-bottom: 1px solid var(--color-border-strong);
  font-weight: 500;
}
.modal__link:hover { border-bottom-color: var(--color-text); }
.modal__muted { font-size: var(--fs-sm); color: var(--color-text-muted); }

.support {
  margin-top: var(--sp-6);
  padding: var(--sp-4);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}
.support__label {
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-subtle);
  margin-bottom: var(--sp-2);
}
.support__text { font-size: var(--fs-sm); color: var(--color-text-muted); margin-bottom: var(--sp-3); }
.support__btn {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  background: var(--color-accent);
  color: var(--color-accent-contrast);
  border-radius: var(--radius-md);
  text-decoration: none;
  font-size: var(--fs-sm);
  font-weight: 500;
}
.support__btn:hover { background: var(--color-accent-hover); }
.support__arrow { font-size: 0.9em; opacity: 0.8; }

/* ==========================================================================
   Print — only the invoice, clean paper
   ========================================================================== */
@media print {
  @page { size: A4; margin: 0; }
  html, body { background: #fff; }
  .toolbar, .editor, .preview-wrap > :not(.invoice), .footer, .modal { display: none !important; }
  .layout { display: block; padding: 0; max-width: none; }
  .preview-wrap { display: block; }
  .invoice {
    border: 0;
    box-shadow: none;
    border-radius: 0;
    padding: 18mm 16mm;
    max-width: none;
    color: #000;
    background: #fff;
  }
  .invoice::before { background: #4338ca; }
  .invoice__eyebrow { color: #4338ca; }
  .invoice__total-row--grand { border-top-color: #000; }
  .invoice__th, .invoice__td, .invoice__meta, .invoice__notes {
    border-color: #d1d5db;
  }
}