:root {
  --bg-primary: #0f0f1a;
  --bg-secondary: #1a1a2e;
  --bg-card: #16162a;
  --bg-hover: #252542;
  --text-primary: #e0e0f0;
  --text-secondary: #a0a0c0;
  --accent: #00d4aa;
  --accent-hover: #00b894;
  --danger: #ff4757;
  --warning: #ffa502;
  --success: #2ed573;
  --border: #2a2a45;
  --shadow: rgba(0, 0, 0, 0.3);
}

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

body {
  font-family: 'Inter', -apple-system, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
}

.hidden { display: none !important; }

/* Screens */
.screen {
  display: none;
  min-height: 100vh;
}
.screen.active { display: flex; }

/* Login */
#login-screen {
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--bg-primary) 0%, #1a1a3e 100%);
}

.auth-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 40px;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 20px 60px var(--shadow);
}

.logo {
  text-align: center;
  margin-bottom: 30px;
}

.logo-icon {
  font-size: 48px;
  margin-bottom: 10px;
}

.logo h1 {
  font-size: 28px;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 5px;
}

.logo p {
  color: var(--text-secondary);
  font-size: 14px;
}

.tabs {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
}

.tab-btn {
  flex: 1;
  padding: 12px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-secondary);
  cursor: pointer;
  font-weight: 500;
  transition: all 0.3s;
}

.tab-btn.active {
  background: var(--accent);
  color: var(--bg-primary);
  border-color: var(--accent);
}

.auth-form input {
  width: 100%;
  padding: 14px;
  margin-bottom: 12px;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 15px;
  transition: border-color 0.3s;
}

.auth-form input:focus {
  outline: none;
  border-color: var(--accent);
}

.btn-primary {
  width: 100%;
  padding: 14px;
  background: var(--accent);
  border: none;
  border-radius: 8px;
  color: var(--bg-primary);
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  transition: background 0.3s;
}

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

.error-msg {
  color: var(--danger);
  font-size: 13px;
  margin-top: 10px;
  text-align: center;
}

/* Dashboard Layout */
#dashboard-screen {
  flex-direction: row;
}

.sidebar {
  width: 260px;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 20px 0;
  position: fixed;
  height: 100vh;
}

.sidebar-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 20px 20px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 20px;
}

.sidebar-header .logo-icon { font-size: 24px; }
.sidebar-header span { font-weight: 700; font-size: 18px; color: var(--accent); }

.sidebar nav {
  flex: 1;
  padding: 0 10px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  color: var(--text-secondary);
  text-decoration: none;
  border-radius: 8px;
  margin-bottom: 4px;
  transition: all 0.3s;
  font-weight: 500;
}

.nav-item:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.nav-item.active {
  background: var(--accent);
  color: var(--bg-primary);
}

.sidebar-footer {
  padding: 20px;
  border-top: 1px solid var(--border);
}

.user-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.user-info span { font-size: 14px; color: var(--text-primary); }

.btn-small {
  padding: 6px 12px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 12px;
}

.btn-small:hover { border-color: var(--danger); color: var(--danger); }

.main-content {
  margin-left: 260px;
  flex: 1;
  padding: 30px;
  min-height: 100vh;
}

/* Pages */
.page { display: none; }
.page.active { display: block; }

.page-header {
  margin-bottom: 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.page-header h2 { font-size: 24px; font-weight: 600; }
.page-header p { color: var(--text-secondary); font-size: 14px; margin-top: 4px; }

/* Stats */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 30px;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
  transition: transform 0.3s;
}

.stat-card:hover { transform: translateY(-2px); }

.stat-icon { font-size: 32px; }

.stat-value {
  display: block;
  font-size: 28px;
  font-weight: 700;
  color: var(--accent);
}

.stat-label {
  font-size: 13px;
  color: var(--text-secondary);
}

/* Lists & Tables */
.list-container, .table-container, .cards-grid {
  overflow-x: auto;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}

.empty {
  text-align: center;
  color: var(--text-secondary);
  padding: 40px;
}

/* Table */
table {
  width: 100%;
  border-collapse: collapse;
}

thead th {
  text-align: left;
  padding: 12px;
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 13px;
  border-bottom: 1px solid var(--border);
}

tbody td {
  padding: 12px;
  border-bottom: 1px solid var(--border);
  font-size: 14px;
}

tbody tr:hover { background: var(--bg-hover); }

/* Status badges */
.badge {
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 500;
}

.badge-connected { background: rgba(46, 213, 115, 0.15); color: var(--success); }
.badge-disconnected { background: rgba(255, 71, 87, 0.15); color: var(--danger); }
.badge-pending { background: rgba(255, 165, 2, 0.15); color: var(--warning); }
.badge-running { background: rgba(0, 212, 170, 0.15); color: var(--accent); }
.badge-sent { background: rgba(46, 213, 115, 0.15); color: var(--success); }
.badge-failed { background: rgba(255, 71, 87, 0.15); color: var(--danger); }

/* Cards Grid (Sessions) */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  padding: 20px;
}

.card-item {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  position: relative;
}

.card-item h4 { font-size: 16px; margin-bottom: 8px; }
.card-item p { font-size: 13px; color: var(--text-secondary); margin-bottom: 12px; }

.card-actions {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

.btn-danger {
  padding: 8px 14px;
  background: rgba(255, 71, 87, 0.1);
  border: 1px solid var(--danger);
  border-radius: 6px;
  color: var(--danger);
  cursor: pointer;
  font-size: 13px;
}

.btn-success {
  padding: 8px 14px;
  background: rgba(46, 213, 115, 0.1);
  border: 1px solid var(--success);
  border-radius: 6px;
  color: var(--success);
  cursor: pointer;
  font-size: 13px;
}

.btn-secondary {
  padding: 8px 14px;
  background: var(--bg-hover);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 13px;
}

/* Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  backdrop-filter: blur(4px);
}

.modal {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 30px;
  width: 100%;
  max-width: 480px;
  display: none;
}

.modal.active { display: block; }

.modal h3 { margin-bottom: 20px; font-size: 18px; }
.modal p { color: var(--text-secondary); font-size: 13px; margin-bottom: 16px; }

.modal input, .modal textarea, .modal select {
  width: 100%;
  padding: 12px;
  margin-bottom: 12px;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 14px;
}

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

.modal-actions {
  display: flex;
  gap: 10px;
  justify-content: flex-end;
  margin-top: 16px;
}

.modal-actions button { width: auto; }

/* QR Box */
.qr-box {
  background: white;
  padding: 20px;
  border-radius: 8px;
  text-align: center;
  margin: 16px 0;
  min-height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #333;
}

.qr-box img { max-width: 200px; }

/* Recent Activity */
.recent-activity {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}

.recent-activity h3 { font-size: 16px; margin-bottom: 16px; }

/* Responsive */
.mobile-header {
  display: none;
  justify-content: space-between;
  align-items: center;
  padding: 15px 20px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  margin: -30px -30px 30px -30px;
}

.sidebar-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 998;
  backdrop-filter: blur(2px);
}

@media (max-width: 768px) {
  .mobile-header {
    display: flex;
  }
  
  .sidebar {
    width: 260px;
    position: fixed;
    top: 0;
    left: -260px;
    height: 100vh;
    z-index: 999;
    transition: left 0.3s ease;
  }
  
  .sidebar.open {
    left: 0;
  }
  
  .main-content {
    margin-left: 0;
    width: 100%;
    padding: 20px;
  }
  
  #dashboard-screen {
    flex-direction: column;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .page-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 15px;
  }
  
  .page-header button {
    width: 100%;
  }
  
  /* Tables */
  .table-container {
    padding: 10px;
  }
  
  /* Modals */
  .modal {
    padding: 20px;
    margin: 10px;
    width: calc(100% - 20px);
    max-height: 90vh;
    overflow-y: auto;
  }
  
  .modal-actions {
    flex-direction: column;
  }
  
  .modal-actions button {
    width: 100%;
  }
}