/* ===== Design tokens ===== */
:root {
  --ink: #1B2430;
  --paper: #FBF8F2;
  --paper-line: #E4DFD3;
  --stamp: #B0413E;
  --slate: #5C6470;
  --slate-soft: #8A8F98;
  --ok-green: #3D6B4F;

  --font-serif: "Source Serif 4", Georgia, serif;
  --font-sans: "Inter", system-ui, -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", "SF Mono", monospace;

  --radius: 3px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.5;
}

/* Faint ledger-paper texture */
body {
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0,
    transparent 27px,
    var(--paper-line) 27px,
    var(--paper-line) 28px
  );
  background-attachment: local;
}

body.no-rule { background-image: none; }

a { color: inherit; text-decoration: none; }

h1, h2, h3 {
  font-family: var(--font-serif);
  font-weight: 600;
  margin: 0 0 0.4em 0;
  letter-spacing: -0.01em;
}

.mono { font-family: var(--font-mono); }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--slate);
}

/* ===== Layout shell ===== */
.shell {
  max-width: 860px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}

.topbar {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  padding-bottom: 20px;
  margin-bottom: 28px;
  border-bottom: 1px solid var(--ink);
  position: relative;
}

.topbar .brand {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
}

.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--paper-line);
  border-radius: var(--radius);
  padding: 6px 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink);
  cursor: pointer;
}

.topbar nav {
  display: flex;
  gap: 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.topbar nav a {
  color: var(--slate);
  border-bottom: 1px solid transparent;
  padding-bottom: 4px;
}
.topbar nav a:hover, .topbar nav a.active {
  color: var(--ink);
  border-bottom-color: var(--stamp);
}

@media (max-width: 640px) {
  .nav-toggle { display: inline-block; }

  .topbar nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    margin-top: 12px;
    background: var(--paper);
    border: 1px solid var(--paper-line);
    border-radius: var(--radius);
    flex-direction: column;
    gap: 0;
    padding: 6px 0;
    z-index: 30;
    box-shadow: 0 6px 18px rgba(27,36,48,0.12);
  }
  .topbar nav.open { display: flex; }
  .topbar nav a {
    padding: 13px 18px;
    border-bottom: none;
  }
  .topbar nav a:hover, .topbar nav a.active {
    background: var(--paper-line);
    border-bottom: none;
  }
}

/* ===== Cards / surfaces ===== */
.card {
  background: #fff;
  border: 1px solid var(--paper-line);
  border-radius: var(--radius);
  padding: 24px;
}

.card + .card { margin-top: 16px; }

/* ===== Forms ===== */
label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--slate);
  margin-bottom: 6px;
}

input, select, textarea {
  width: 100%;
  font-family: var(--font-sans);
  font-size: 15px;
  padding: 10px 12px;
  background: #fff;
  border: 1px solid var(--paper-line);
  border-radius: var(--radius);
  color: var(--ink);
}

input:focus, select:focus, textarea:focus {
  outline: 2px solid var(--stamp);
  outline-offset: 1px;
  border-color: var(--stamp);
}

.field { margin-bottom: 16px; }

.field-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

@media (max-width: 560px) {
  .field-row { grid-template-columns: 1fr; }
}

/* ===== Buttons ===== */
.btn {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 11px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn:hover { background: #2A3647; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--paper-line);
}
.btn-ghost:hover { border-color: var(--ink); background: transparent; }

.btn-stamp {
  background: var(--stamp);
  border-color: var(--stamp);
  color: #fff;
}
.btn-stamp:hover { background: #94322f; }

.btn-danger {
  background: transparent;
  color: var(--stamp);
  border-color: var(--paper-line);
}
.btn-danger:hover { border-color: var(--stamp); }

/* ===== Error / empty states ===== */
.error-banner {
  font-family: var(--font-mono);
  font-size: 13px;
  background: #FBEAEA;
  border: 1px solid var(--stamp);
  color: #7A2A28;
  border-radius: var(--radius);
  padding: 12px 14px;
  margin-bottom: 16px;
}

.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--slate);
}
.empty-state h3 { color: var(--ink); }

/* ===== Lists ===== */
.list-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
  border-bottom: 1px solid var(--paper-line);
}
.list-row:last-child { border-bottom: none; }

.list-row .primary { font-weight: 600; }
.list-row .secondary { color: var(--slate); font-size: 13px; }
.list-row .amount { font-family: var(--font-mono); font-size: 16px; }

.list-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 18px;
}

/* ===== Status pill (small, list contexts) ===== */
.status-pill {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 3px 8px;
  border-radius: 12px;
  border: 1px solid currentColor;
}
.status-pill.DRAFT    { color: var(--slate); }
.status-pill.SENT     { color: #8A6D1F; }
.status-pill.PAID     { color: var(--ok-green); }
.status-pill.OVERDUE  { color: var(--stamp); }
.status-pill.CANCELLED{ color: var(--slate-soft); }

/* ===== The stamp (signature element) ===== */
.stamp {
  position: absolute;
  top: 28px;
  right: 28px;
  width: 110px;
  height: 110px;
  border: 3px solid var(--stamp);
  border-radius: 50%;
  color: var(--stamp);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 17px;
  letter-spacing: 0.08em;
  transform: rotate(-12deg);
  opacity: 0.85;
  text-align: center;
  pointer-events: none;
  mix-blend-mode: multiply;
}
.stamp::before {
  content: "";
  position: absolute;
  inset: 6px;
  border: 1px solid var(--stamp);
  border-radius: 50%;
}
.stamp.DRAFT { border-color: var(--slate-soft); color: var(--slate-soft); }
.stamp.DRAFT::before { border-color: var(--slate-soft); }
.stamp.SENT { border-color: #8A6D1F; color: #8A6D1F; }
.stamp.SENT::before { border-color: #8A6D1F; }
.stamp.PAID { border-color: var(--ok-green); color: var(--ok-green); }
.stamp.PAID::before { border-color: var(--ok-green); }

/* ===== Invoice document ===== */
.invoice-doc {
  position: relative;
  background: #fff;
  border: 1px solid var(--paper-line);
  padding: 40px;
  overflow: hidden;
}

.invoice-head {
  display: flex;
  justify-content: space-between;
  margin-bottom: 36px;
  padding-bottom: 24px;
  padding-right: 130px; /* clears the status stamp in the top-right corner */
  border-bottom: 2px solid var(--ink);
}

@media (max-width: 480px) {
  .stamp {
    width: 84px;
    height: 84px;
    top: 20px;
    right: 20px;
    font-size: 12px;
  }
  .invoice-head { padding-right: 96px; }
}

.invoice-head .num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--slate);
}

table.line-items {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 24px;
}
table.line-items th {
  text-align: left;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--slate);
  padding: 8px 0;
  border-bottom: 1px solid var(--ink);
}
table.line-items th.num, table.line-items td.num { text-align: right; }
table.line-items td {
  padding: 10px 0;
  border-bottom: 1px solid var(--paper-line);
  font-size: 14px;
}
table.line-items td.num { font-family: var(--font-mono); }

.totals {
  margin-left: auto;
  width: 260px;
}
.totals .row {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  font-family: var(--font-mono);
  font-size: 14px;
}
.totals .row.grand {
  border-top: 2px solid var(--ink);
  margin-top: 6px;
  padding-top: 12px;
  font-size: 18px;
  font-weight: 700;
}

/* ===== Utility ===== */
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.muted { color: var(--slate); }
.center-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}
.auth-card { width: 100%; max-width: 380px; }
.text-link {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--slate);
  border-bottom: 1px solid var(--paper-line);
}
.text-link:hover { color: var(--stamp); border-bottom-color: var(--stamp); }