:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  --success: #16a34a;
  --success-light: #f0fdf4;
  --warning: #d97706;
  --warning-light: #fffbeb;
  --danger: #dc2626;
  --danger-light: #fef2f2;
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --border: #e2e8f0;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --radius: 8px;
  --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

body {
  background-color: var(--bg-main);
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header & Navbar */
.navbar {
  background: #ffffff;
  border-bottom: 1px solid var(--border);
  padding: 0.85rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.15rem;
  font-weight: 700;
  color: #1e293b;
}

.nav-brand svg {
  color: var(--primary);
}

.nav-user {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.badge-role {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 9999px;
  text-transform: uppercase;
}
.badge-admin { background: #fee2e2; color: #991b1b; }
.badge-billing { background: #fef3c7; color: #92400e; }
.badge-client { background: #dbeafe; color: #1e40af; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease-in-out;
  text-decoration: none;
}

.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-hover); }

.btn-success { background: var(--success); color: white; }
.btn-success:hover { background: #15803d; }

.btn-outline {
  background: white;
  border-color: var(--border);
  color: var(--text-main);
}
.btn-outline:hover { background: #f1f5f9; }

.btn-danger { background: var(--danger); color: white; }
.btn-danger:hover { background: #b91c1c; }

.btn-sm { padding: 0.35rem 0.7rem; font-size: 0.8rem; }

/* Container & Layout */
.container {
  max-width: 1400px;
  width: 100%;
  margin: 0 auto;
  padding: 1.5rem;
  flex: 1;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  margin-bottom: 1.5rem;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: #1e293b;
}

.card-subtitle {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-bottom: 1.25rem;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0.5rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1.5rem;
}

.tab-btn {
  padding: 0.65rem 1.25rem;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.15s;
}

.tab-btn.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

/* Forms & Inputs */
.form-group {
  margin-bottom: 1rem;
}

.form-label {
  display: block;
  font-size: 0.825rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
  color: #334155;
}

.form-control {
  width: 100%;
  padding: 0.55rem 0.8rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  font-size: 0.9rem;
  background: white;
  transition: border-color 0.15s;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

/* Equipment Cards (Client view) */
.equipment-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 1.25rem;
}

.equipment-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
}

.eq-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.75rem;
}

.eq-title {
  font-weight: 700;
  font-size: 1.05rem;
  color: #1e293b;
}

.eq-tag {
  font-size: 0.75rem;
  background: #f1f5f9;
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  color: #475569;
  font-weight: 500;
}

.prev-reading-box {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 6px;
  padding: 0.65rem 0.85rem;
  margin-bottom: 1rem;
  font-size: 0.825rem;
}

.prev-reading-box strong {
  color: #0f172a;
}

.live-consumption {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--primary);
  margin-top: 0.35rem;
}

.alert-warning {
  background: var(--warning-light);
  border: 1px solid #fde68a;
  color: #92400e;
  padding: 0.6rem 0.8rem;
  border-radius: 6px;
  font-size: 0.8rem;
  margin-top: 0.5rem;
}

/* Billing Full Grid Table */
.table-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: white;
  box-shadow: var(--shadow);
}

.grid-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.825rem;
  text-align: center;
  white-space: nowrap;
}

.grid-table th, .grid-table td {
  padding: 0.45rem 0.6rem;
  border: 1px solid #cbd5e1;
}

.grid-table th {
  background: #f1f5f9;
  font-weight: 700;
  color: #334155;
  position: sticky;
  top: 0;
}

.grid-table .client-cell {
  text-align: left;
  font-weight: 700;
  background: #ffffff;
  position: sticky;
  left: 0;
  z-index: 10;
}

.grid-table .machine-cell {
  text-align: left;
  background: #ffffff;
  position: sticky;
  left: 140px;
  z-index: 10;
  font-weight: 500;
}

.grid-table tr:hover td {
  background-color: #f8fafc !important;
}

.month-billed {
  background: #dcfce7 !important;
  color: #15803d !important;
  font-weight: 700;
}

.month-pending {
  background: #fef9c3 !important;
  color: #a16207 !important;
  font-weight: 700;
}

/* Modals */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0, 0, 0, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}

.modal-content {
  background: white;
  border-radius: var(--radius);
  padding: 1.75rem;
  max-width: 550px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-md);
}

/* Utilities */
.text-right { text-align: right; }
.text-center { text-align: center; }
.mt-4 { margin-top: 1rem; }
.mb-4 { margin-bottom: 1rem; }
.flex { display: flex; }
.justify-between { justify-content: space-between; }
.align-center { align-items: center; }
.gap-2 { gap: 0.5rem; }
.gap-4 { gap: 1rem; }
.hidden { display: none !important; }