:root {
  --bg-dark: #0f172a;
  --bg-card: rgba(30, 41, 59, 0.7);
  --bg-card-hover: rgba(30, 41, 59, 0.9);
  --border-color: rgba(255, 255, 255, 0.08);
  --primary: #10b981;
  --primary-hover: #059669;
  --primary-glow: rgba(16, 185, 129, 0.3);
  --accent: #3b82f6;
  --danger: #ef4444;
  --warning: #f59e0b;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --radius: 14px;
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg-dark);
  background-image: 
    radial-gradient(at 0% 0%, rgba(16, 185, 129, 0.12) 0px, transparent 50%),
    radial-gradient(at 100% 100%, rgba(59, 130, 246, 0.12) 0px, transparent 50%);
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  overflow-x: hidden;
}

/* Sidebar Layout */
.app-container {
  display: flex;
  width: 100vw;
  min-height: 100vh;
}

.sidebar {
  width: 260px;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  border-right: 1px solid var(--border-color);
  padding: 24px 18px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 36px;
}

.brand-icon {
  width: 42px;
  height: 42px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  box-shadow: 0 0 20px var(--primary-glow);
}

.brand-title {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.brand-subtitle {
  font-size: 11px;
  color: var(--text-muted);
}

.nav-menu {
  display: flex;
  flex-direction: column;
  gap: 8px;
  list-style: none;
}

.nav-item button {
  width: 100%;
  padding: 12px 16px;
  border-radius: 10px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  transition: var(--transition);
  text-align: left;
}

.nav-item button:hover {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
}

.nav-item.active button {
  background: linear-gradient(90deg, rgba(16, 185, 129, 0.15), rgba(59, 130, 246, 0.05));
  color: var(--primary);
  border-left: 3px solid var(--primary);
  font-weight: 600;
}

.sidebar-footer {
  font-size: 12px;
  color: var(--text-muted);
  border-top: 1px solid var(--border-color);
  padding-top: 16px;
  text-align: center;
}

/* Main Content Area */
.main-content {
  flex: 1;
  padding: 32px 40px;
  overflow-y: auto;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 32px;
}

.header-title h1 {
  font-size: 26px;
  font-weight: 700;
}

.header-title p {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 4px;
}

.status-pill {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(30, 41, 59, 0.8);
  border: 1px solid var(--border-color);
  border-radius: 30px;
  font-size: 13px;
  font-weight: 600;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--text-muted);
}

.dot.connected {
  background: var(--primary);
  box-shadow: 0 0 10px var(--primary);
}

.dot.connecting {
  background: var(--warning);
  animation: pulse 1.5s infinite;
}

.dot.qr_ready {
  background: var(--accent);
  animation: pulse 1.5s infinite;
}

.dot.disconnected {
  background: var(--danger);
}

@keyframes pulse {
  0% { opacity: 0.4; }
  50% { opacity: 1; }
  100% { opacity: 0.4; }
}

/* Tab Panels */
.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Dashboard Cards Grid */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 28px;
}

.stat-card {
  background: var(--bg-card);
  backdrop-filter: blur(8px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
}

.stat-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.05);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
}

.stat-value {
  font-size: 22px;
  font-weight: 700;
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
}

.card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.card-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 10px;
}

/* QR Code Section */
.qr-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
  border: 2px dashed var(--border-color);
  border-radius: var(--radius);
  min-height: 280px;
  background: rgba(15, 23, 42, 0.4);
}

.qr-image {
  width: 220px;
  height: 220px;
  border-radius: 12px;
  border: 4px solid #fff;
  box-shadow: 0 0 25px rgba(0, 0, 0, 0.5);
}

.qr-placeholder {
  text-align: center;
  color: var(--text-muted);
}

.btn-group {
  display: flex;
  gap: 12px;
  margin-top: 24px;
  flex-wrap: wrap;
}

.btn {
  padding: 11px 20px;
  border-radius: 8px;
  border: none;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: var(--transition);
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-hover);
  box-shadow: 0 0 15px var(--primary-glow);
}

.btn-danger {
  background: rgba(239, 68, 68, 0.15);
  color: var(--danger);
  border: 1px solid rgba(239, 68, 68, 0.3);
}

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

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-main);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
}

/* Form Styles */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 6px;
}

textarea, input {
  width: 100%;
  padding: 12px 14px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background: rgba(15, 23, 42, 0.6);
  color: var(--text-main);
  font-family: inherit;
  font-size: 14px;
  transition: var(--transition);
}

textarea:focus, input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 10px var(--primary-glow);
}

/* History Table */
.table-container {
  width: 100%;
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 14px;
}

th {
  padding: 14px 16px;
  background: rgba(15, 23, 42, 0.5);
  color: var(--text-muted);
  font-weight: 600;
  border-bottom: 1px solid var(--border-color);
}

td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-main);
}

tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

.pre-box {
  background: #090d16;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  font-family: 'Courier New', Courier, monospace;
  font-size: 13px;
  color: #a7f3d0;
  white-space: pre-wrap;
  max-height: 250px;
  overflow-y: auto;
}

.badge {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 11px;
  font-weight: 600;
  background: rgba(16, 185, 129, 0.2);
  color: var(--primary);
}