:root {
  --bg-base: #0f172a;
  --bg-surface: #1e293b;
  --bg-card: #1e293b;
  --bg-card-hover: #334155;
  --border-color: #334155;
  --border-light: #475569;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --primary: #38bdf8;
  --primary-hover: #0284c7;
  --success: #10b981;
  --success-bg: rgba(16, 185, 129, 0.15);
  --warning: #f59e0b;
  --warning-bg: rgba(245, 158, 11, 0.15);
  --danger: #ef4444;
  --danger-bg: rgba(239, 68, 68, 0.15);
  --info: #818cf8;
  --sidebar-width: 240px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-base);
  color: var(--text-main);
  line-height: 1.5;
  min-height: 100vh;
}

/* Typography & Utilities */
h1, h2, h3, h4 {
  font-weight: 600;
  color: #fff;
}
p { margin-bottom: 0.5rem; }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }
.text-info { color: var(--info); }
.text-center { text-align: center; }
.mt-3 { margin-top: 1rem; }
.mt-4 { margin-top: 1.5rem; }
.mb-3 { margin-bottom: 1rem; }
.flex-between { display: flex; justify-content: space-between; align-items: center; }
.flex-gap { display: flex; gap: 0.75rem; align-items: center; }
code {
  background: #090d16;
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-family: monospace;
  font-size: 0.875em;
  color: #38bdf8;
}

/* Login Card */
.login-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: radial-gradient(circle at top, #1e293b 0%, #0f172a 100%);
  padding: 1.5rem;
}
.login-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 2.5rem;
  width: 100%;
  max-width: 420px;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
}
.login-header {
  text-align: center;
  margin-bottom: 2rem;
}
.logo-icon {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}
.subtitle {
  color: var(--text-muted);
  font-size: 0.9rem;
}
.login-footer {
  margin-top: 2rem;
  text-align: center;
  color: var(--text-muted);
}

/* App Layout */
.app-layout {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

/* Topbar */
.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  padding: 0 1.5rem;
  height: 60px;
  flex-shrink: 0;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.brand-icon { font-size: 1.5rem; }
.brand-name {
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}
.brand-accent { color: var(--primary); }
.topbar-right {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.user-menu {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  border-left: 1px solid var(--border-color);
  padding-left: 1rem;
}
.user-name { font-weight: 600; font-size: 0.9rem; }

/* Main Body & Sidebar */
.main-body {
  display: flex;
  flex: 1;
  overflow: hidden;
}
.sidebar {
  width: var(--sidebar-width);
  background: var(--bg-surface);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  padding: 1.25rem 0.75rem;
  overflow-y: auto;
  flex-shrink: 0;
}
.nav-section-title {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  padding: 0.75rem 0.5rem 0.25rem;
}
.nav-list { list-style: none; margin-bottom: 1rem; }
.nav-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 0.75rem;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.9rem;
  color: var(--text-muted);
  transition: all 0.15s ease;
}
.nav-item:hover {
  background: var(--bg-card-hover);
  color: #fff;
}
.nav-item.active {
  background: rgba(56, 189, 248, 0.15);
  color: var(--primary);
  font-weight: 600;
}
.sidebar-footer {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--border-color);
  text-align: center;
}
.cluster-pill {
  background: #090d16;
  padding: 0.4rem 0.6rem;
  border-radius: 6px;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Content Area */
.content-view {
  flex: 1;
  padding: 2rem;
  overflow-y: auto;
  background: var(--bg-base);
}
.tab-pane { display: none; }
.tab-pane.active { display: block; }
.view-header {
  margin-bottom: 1.5rem;
}

/* Cards & Grid */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.25rem;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}
.card-header {
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.75rem;
  margin-bottom: 1rem;
}
.metrics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 1.25rem;
}
.metric-card {
  padding: 1.5rem;
}
.metric-title {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}
.metric-value {
  font-size: 2rem;
  font-weight: 700;
  margin: 0.25rem 0;
}
.metric-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
}
.detail-row {
  display: flex;
  justify-content: space-between;
  padding: 0.4rem 0;
  border-bottom: 1px solid rgba(255,255,255,0.05);
  font-size: 0.9rem;
}
.detail-row:last-child { border-bottom: none; }

/* Forms & Inputs */
.form-group {
  margin-bottom: 1.25rem;
}
.form-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 0.35rem;
  color: #e2e8f0;
}
.form-control {
  width: 100%;
  padding: 0.6rem 0.8rem;
  background: #090d16;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: #fff;
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.2s;
}
.form-control:focus {
  border-color: var(--primary);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.6rem 1.2rem;
  font-size: 0.9rem;
  font-weight: 500;
  border-radius: 6px;
  border: none;
  cursor: pointer;
  transition: all 0.15s;
}
.btn-primary {
  background: var(--primary);
  color: #0f172a;
}
.btn-primary:hover {
  background: var(--primary-hover);
  color: #fff;
}
.btn-outline {
  background: transparent;
  border: 1px solid var(--border-light);
  color: var(--text-main);
}
.btn-outline:hover {
  background: var(--bg-card-hover);
}
.btn-danger-outline {
  background: transparent;
  border: 1px solid var(--danger);
  color: var(--danger);
}
.btn-danger-outline:hover {
  background: var(--danger);
  color: #fff;
}
.btn-sm {
  padding: 0.35rem 0.75rem;
  font-size: 0.8rem;
}
.btn-block { width: 100%; }

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.6rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
}
.badge-success { background: var(--success-bg); color: var(--success); }
.badge-warning { background: var(--warning-bg); color: var(--warning); }
.badge-danger { background: var(--danger-bg); color: var(--danger); }
.badge-subtle { background: #334155; color: #94a3b8; }

/* Tables */
.table-responsive {
  overflow-x: auto;
}
.table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.9rem;
}
.table th {
  background: #131d2e;
  padding: 0.75rem 1rem;
  color: var(--text-muted);
  font-weight: 600;
  border-bottom: 1px solid var(--border-color);
}
.table td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  vertical-align: middle;
}
.table tbody tr:hover {
  background: rgba(255, 255, 255, 0.02);
}

/* Modals */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}
.modal-dialog {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  width: 100%;
  max-width: 500px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
  overflow: hidden;
}
.modal-header {
  padding: 1.25rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.modal-close {
  background: transparent;
  border: none;
  font-size: 1.5rem;
  color: var(--text-muted);
  cursor: pointer;
}
.modal-body {
  padding: 1.5rem;
}
.modal-footer {
  padding: 1rem 1.5rem;
  background: #131d2e;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
}

/* Alerts & Toasts */
.alert {
  padding: 0.75rem 1rem;
  border-radius: 6px;
  margin-bottom: 1rem;
  font-size: 0.85rem;
}
.alert-danger {
  background: var(--danger-bg);
  border: 1px solid var(--danger);
  color: #fca5a5;
}
.toast-container {
  position: fixed;
  top: 1.5rem;
  right: 1.5rem;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.toast {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  padding: 0.75rem 1.25rem;
  border-radius: 6px;
  color: #fff;
  box-shadow: 0 10px 15px -3px rgba(0,0,0,0.5);
  font-size: 0.85rem;
  animation: slideIn 0.2s ease-out;
}
@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}