:root {
  --bg-color: #0f172a;
  --panel-bg: #1e293b;
  --border-color: #334155;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --success: #10b981;
  --danger: #ef4444;
  --warning: #f59e0b;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg-color);
  color: var(--text-main);
  height: 100vh;
  overflow: hidden;
}

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

header {
  background: var(--panel-bg);
  border-bottom: 1px solid var(--border-color);
  padding: 10px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: #60a5fa;
}

nav button {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  padding: 6px 14px;
  margin-right: 8px;
  border-radius: 6px;
  cursor: pointer;
}

nav button.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.pos-container {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 16px;
  padding: 16px;
  height: calc(100vh - 60px);
}

.panel {
  background: var(--panel-bg);
  border-radius: 8px;
  border: 1px solid var(--border-color);
  padding: 16px;
  display: flex;
  flex-direction: column;
}

.barcode-box {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.barcode-box input {
  flex: 1;
  background: #0f172a;
  border: 1px solid var(--border-color);
  color: white;
  padding: 12px;
  border-radius: 6px;
  font-size: 1.1rem;
}

.cart-table {
  width: 100%;
  border-collapse: collapse;
  flex: 1;
  overflow-y: auto;
}

.cart-table th, .cart-table td {
  padding: 10px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.cart-table th {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.summary-card {
  background: #0f172a;
  padding: 16px;
  border-radius: 8px;
  margin-top: auto;
}

.summary-row {
  display: flex;
  justify-content: space-between;
  font-size: 1.5rem;
  font-weight: bold;
  color: #38bdf8;
  margin-bottom: 16px;
}

.key-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.btn-key {
  padding: 14px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.btn-cash { background: #059669; color: white; }
.btn-card { background: #2563eb; color: white; }
.btn-credit { background: #d97706; color: white; }
.btn-void { background: #dc2626; color: white; }

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}

.modal-content {
  background: var(--panel-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  width: 480px;
  max-width: 90%;
  padding: 20px;
}