:root {
  --bg: #f5f0eb;
  --surface: #fdfaf6;
  --surface2: #f0e8de;
  --border: #c8b89a;
  --accent: #8B5E3C;
  --accent-hover: #6e4a2e;
  --accent2: #4E9AF1;
  --text: #2a1f14;
  --text-muted: #7a6555;
  --danger: #c0392b;
  --success: #27ae60;
  --radius: 8px;
  --shadow: 0 2px 8px rgba(0,0,0,0.1);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

/* ── Auth ───────────────────────────────────────────────────── */

#auth-screen {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 1rem;
}

.auth-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 2.5rem 2rem;
  width: 100%;
  max-width: 380px;
}

.auth-card h1 {
  font-size: 1.7rem;
  color: var(--accent);
  margin-bottom: 0.25rem;
}

.auth-card p.tagline {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 1.8rem;
}

.auth-tabs {
  display: flex;
  gap: 0;
  margin-bottom: 1.5rem;
  border-bottom: 2px solid var(--border);
}

.auth-tab {
  flex: 1;
  padding: 0.5rem;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
  color: var(--text-muted);
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: color 0.2s, border-color 0.2s;
}

.auth-tab.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
  font-weight: 600;
}

/* ── Form elements ──────────────────────────────────────────── */

.form-group {
  margin-bottom: 1rem;
}

label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 0.3rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

input[type="text"], input[type="email"], input[type="password"],
input[type="number"], select, textarea {
  width: 100%;
  padding: 0.55rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  font-size: 0.95rem;
  transition: border-color 0.2s;
}

input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--accent);
}

/* ── Buttons ────────────────────────────────────────────────── */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.55rem 1.1rem;
  border: none;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}

.btn:active { transform: scale(0.98); }
.btn:disabled { opacity: 0.5; cursor: default; }

.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover:not(:disabled) { background: var(--accent-hover); }

.btn-secondary { background: var(--surface2); color: var(--text); border: 1px solid var(--border); }
.btn-secondary:hover:not(:disabled) { background: var(--border); }

.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover:not(:disabled) { background: #a93226; }

.btn-success { background: var(--success); color: #fff; }
.btn-success:hover:not(:disabled) { background: #229954; }

.btn-sm { padding: 0.3rem 0.6rem; font-size: 0.8rem; }
.btn-full { width: 100%; justify-content: center; }

/* ── App layout ─────────────────────────────────────────────── */

#app-screen {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

header {
  background: var(--accent);
  color: #fff;
  padding: 0 1.5rem;
  height: 52px;
  display: flex;
  align-items: center;
  gap: 1rem;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
}

header h1 {
  font-size: 1.3rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}

header .spacer { flex: 1; }

header .user-info {
  font-size: 0.85rem;
  opacity: 0.85;
}

.app-body {
  display: flex;
  flex: 1;
  overflow: hidden;
}

/* ── Sidebar ────────────────────────────────────────────────── */

#sidebar {
  width: 240px;
  min-width: 240px;
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.sidebar-header {
  padding: 1rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

#project-list {
  flex: 1;
  overflow-y: auto;
  padding: 0.5rem 0;
}

.project-item {
  padding: 0.65rem 1rem;
  cursor: pointer;
  font-size: 0.9rem;
  border-left: 3px solid transparent;
  transition: background 0.15s;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.project-item:hover { background: var(--bg); }

.project-item.active {
  background: var(--bg);
  border-left-color: var(--accent);
  font-weight: 600;
  color: var(--accent);
}

.project-item .del-btn {
  opacity: 0;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--danger);
  font-size: 0.9rem;
  padding: 0 0.2rem;
  line-height: 1;
}

.project-item:hover .del-btn { opacity: 0.6; }
.project-item .del-btn:hover { opacity: 1; }

/* ── Main content ───────────────────────────────────────────── */

#main {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
}

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 60vh;
  text-align: center;
  color: var(--text-muted);
}

.empty-state .icon { font-size: 3.5rem; margin-bottom: 1rem; }
.empty-state h2 { font-size: 1.2rem; margin-bottom: 0.5rem; }

/* ── Project header ─────────────────────────────────────────── */

.project-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.project-name-input {
  font-size: 1.4rem;
  font-weight: 700;
  border: none;
  border-bottom: 2px solid transparent;
  background: transparent;
  color: var(--text);
  padding: 0.2rem 0;
  width: auto;
  min-width: 200px;
}

.project-name-input:focus {
  outline: none;
  border-bottom-color: var(--accent);
}

/* ── Panels ─────────────────────────────────────────────────── */

.panels {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

@media (max-width: 900px) { .panels { grid-template-columns: 1fr; } }

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.panel-header {
  background: var(--surface2);
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border);
  font-weight: 700;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.panel-body { padding: 1rem; }

/* ── Tables ─────────────────────────────────────────────────── */

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin-bottom: 1rem;
}

th {
  text-align: left;
  padding: 0.4rem 0.5rem;
  background: var(--surface2);
  color: var(--text-muted);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  border-bottom: 1px solid var(--border);
}

td {
  padding: 0.45rem 0.5rem;
  border-bottom: 1px solid var(--surface2);
  vertical-align: middle;
}

tr:last-child td { border-bottom: none; }
tr:hover td { background: var(--bg); }

.empty-row td {
  text-align: center;
  color: var(--text-muted);
  padding: 1.2rem;
  font-style: italic;
}

/* ── Add-row form ───────────────────────────────────────────── */

.add-row {
  display: grid;
  gap: 0.5rem;
  padding: 0.75rem;
  background: var(--bg);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
}

.add-row-fields {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.add-row-fields .field { flex: 1; min-width: 70px; }
.add-row-fields .field-wide { flex: 2; min-width: 110px; }

.add-row-fields input, .add-row-fields select {
  padding: 0.4rem 0.5rem;
  font-size: 0.85rem;
}

.add-row-actions {
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
}

/* ── Compute area ───────────────────────────────────────────── */

.compute-bar {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
}

.kerf-input {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.kerf-input input {
  width: 65px;
  padding: 0.35rem 0.5rem;
  font-size: 0.9rem;
}

/* ── Results ────────────────────────────────────────────────── */

#results-section { margin-top: 0.5rem; }

.result-stats {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.stat-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.75rem 1.2rem;
  text-align: center;
  min-width: 130px;
}

.stat-card .val {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
}

.stat-card .lbl {
  font-size: 0.78rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.stat-card .stat-sub {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 0.1rem;
  font-style: italic;
}

.unplaced-warning {
  background: #fef9e7;
  border: 1px solid #f0c040;
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
  font-size: 0.9rem;
  color: #7d6608;
}

.sheet-diagrams {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(380px, 1fr));
  gap: 1rem;
}

.sheet-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.sheet-card-header {
  background: var(--surface2);
  padding: 0.5rem 0.75rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
}

.sheet-card-header strong { color: var(--accent); }
.sheet-card-header .eff { color: var(--text-muted); }

.sheet-card img, .sheet-card object {
  width: 100%;
  display: block;
}

/* ── AI Tips ────────────────────────────────────────────────── */

.ai-tips {
  margin-top: 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.ai-tips summary {
  padding: 0.75rem 1rem;
  cursor: pointer;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--accent2);
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--surface2);
  border-bottom: 1px solid var(--border);
}

.ai-tips summary::-webkit-details-marker { display: none; }

.ai-tips-body {
  padding: 1rem;
  font-size: 0.92rem;
  line-height: 1.6;
  white-space: pre-wrap;
  color: var(--text);
}

/* ── Buttons extra sizes ─────────────────────────────────────── */

.btn-xs {
  padding: 0.2rem 0.45rem;
  font-size: 0.78rem;
  border-radius: 4px;
  min-width: 0;
}

.row-actions {
  white-space: nowrap;
  display: flex;
  gap: 0.3rem;
  align-items: center;
}

/* ── Inline edit rows ────────────────────────────────────────── */

tr.editing td {
  background: #fdf8f0;
  padding: 0.3rem 0.4rem;
}

.edit-input {
  width: 100%;
  padding: 0.3rem 0.4rem;
  font-size: 0.85rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: white;
  color: var(--text);
  min-width: 0;
}

.edit-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(139,94,60,0.15);
}

.edit-num { width: 70px; }

.edit-asm-select {
  font-size: 0.78rem;
  padding: 0.2rem 0.3rem;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: white;
  color: var(--text);
  max-width: 110px;
  margin-right: 0.2rem;
}

/* ── Assembly groups ─────────────────────────────────────────── */

#parts-panel-body {
  padding: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.assembly-group {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
}

.assembly-hdr {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.55rem 0.75rem;
  background: var(--surface2);
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}

.asm-icon { font-size: 0.9rem; }

.asm-name {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--accent);
  flex: 1;
  min-width: 80px;
}

.asm-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-style: italic;
}

/* ── Qty stepper ─────────────────────────────────────────────── */

.qty-stepper {
  display: flex;
  align-items: center;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  background: white;
}

.btn-stepper {
  background: var(--surface2);
  border: none;
  padding: 0.25rem 0.55rem;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  color: var(--accent);
  line-height: 1;
  transition: background 0.15s;
}

.btn-stepper:hover { background: var(--border); }

.qty-val {
  padding: 0.25rem 0.55rem;
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text);
  min-width: 36px;
  text-align: center;
  background: white;
}

/* ── Standalone section ──────────────────────────────────────── */

.standalone-section {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
}

.standalone-hdr {
  padding: 0.45rem 0.75rem;
  background: var(--surface2);
  border-bottom: 1px solid var(--border);
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

.no-parts-msg {
  padding: 0.75rem 1rem;
  color: var(--text-muted);
  font-style: italic;
  font-size: 0.85rem;
}

.parts-table {
  margin-bottom: 0;
}

.notes-cell {
  max-width: 120px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* ── Misc ────────────────────────────────────────────────────── */

.error-msg {
  background: #fde8e8;
  border: 1px solid #f5b7b1;
  color: #922b21;
  border-radius: var(--radius);
  padding: 0.6rem 0.9rem;
  font-size: 0.88rem;
  margin-top: 0.5rem;
}

.spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255,255,255,0.4);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  vertical-align: middle;
}

@keyframes spin { to { transform: rotate(360deg); } }

.hidden { display: none !important; }