:root {
  --bg-primary: #0a0e17;
  --bg-secondary: #111928;
  --bg-card: rgba(18, 26, 43, 0.75);
  --bg-glass: rgba(25, 35, 58, 0.45);
  --border-glow: rgba(0, 242, 254, 0.25);
  --border-subtle: rgba(255, 255, 255, 0.08);

  --accent-cyan: #00f2fe;
  --accent-blue: #4facfe;
  --accent-purple: #9d4edd;
  --accent-pink: #f72585;
  --accent-green: #10b981;
  --accent-yellow: #f59e0b;
  --accent-red: #ef4444;

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;

  --font-sans: 'Outfit', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.25);
  --shadow-glow: 0 0 25px rgba(0, 242, 254, 0.2);
  --shadow-glow-purple: 0 0 25px rgba(157, 78, 221, 0.25);
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-main);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.5;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(79, 172, 254, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 85% 85%, rgba(157, 78, 221, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 50% 50%, rgba(0, 242, 254, 0.03) 0%, transparent 60%);
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent-cyan);
}

/* Header */
.app-header {
  height: 68px;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo-group {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-badge {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-glow);
}

.logo-badge svg {
  width: 22px;
  height: 22px;
  color: #fff;
}

.brand-title {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  background: linear-gradient(90deg, #fff, var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.env-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 3px 8px;
  background: rgba(0, 242, 254, 0.12);
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 242, 254, 0.3);
  border-radius: var(--radius-sm);
  margin-left: 8px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  border: none;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
  color: white;
  box-shadow: var(--shadow-glow-purple);
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 0 30px rgba(157, 78, 221, 0.45);
}

.btn-cyan {
  background: linear-gradient(135deg, #00f2fe, #4facfe);
  color: #051329;
  font-weight: 700;
  box-shadow: var(--shadow-glow);
}
.btn-cyan:hover {
  transform: translateY(-1px);
  filter: brightness(1.1);
}

.btn-outline {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
}
.btn-outline:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
}

.btn-outline.active {
  background: rgba(0, 242, 254, 0.15);
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

/* Main Layout Grid */
.main-container {
  max-width: 1720px;
  margin: 0 auto;
  padding: 1.5rem;
  display: grid;
  grid-template-columns: 1.25fr 0.75fr;
  gap: 1.5rem;
}

@media (max-width: 1200px) {
  .main-container {
    grid-template-columns: 1fr;
  }
}

/* Glass Card */
.glass-card {
  background: var(--bg-card);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.glass-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.15), transparent);
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-subtle);
}

.card-title {
  font-size: 1.05rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}

.card-title svg {
  color: var(--accent-cyan);
}

/* Simulation Section */
.sim-viewport-wrapper {
  position: relative;
  width: 100%;
  height: 520px;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: #050811;
  border: 1px solid rgba(0, 242, 254, 0.15);
}

#sim-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.sim-hud-overlay {
  position: absolute;
  top: 14px;
  left: 14px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.hud-badge {
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(10px);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 255, 255, 0.1);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-green);
  box-shadow: 0 0 8px var(--accent-green);
}
.status-dot.learning {
  background: var(--accent-yellow);
  box-shadow: 0 0 8px var(--accent-yellow);
  animation: pulse 1.5s infinite;
}

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

.sim-controls-floating {
  position: absolute;
  bottom: 14px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 8px;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  padding: 6px 10px;
  border-radius: var(--radius-full);
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.camera-presets {
  position: absolute;
  top: 14px;
  right: 14px;
  display: flex;
  gap: 6px;
}

.btn-icon {
  width: 34px;
  height: 34px;
  padding: 0;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
}
.btn-icon:hover, .btn-icon.active {
  color: var(--accent-cyan);
  border-color: var(--accent-cyan);
  background: rgba(0, 242, 254, 0.1);
}

/* Checkpoint Timeline Bar */
.checkpoint-nav {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  margin-top: 1rem;
}

.checkpoint-btn {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 10px;
  text-align: left;
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
  overflow: hidden;
}

.checkpoint-btn:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.2);
}

.checkpoint-btn.active {
  background: rgba(0, 242, 254, 0.08);
  border-color: var(--accent-cyan);
  box-shadow: 0 0 20px rgba(0, 242, 254, 0.15);
}

.checkpoint-btn.active::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 4px;
  background: var(--accent-cyan);
}

.cp-step {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-cyan);
  font-weight: 600;
  text-transform: uppercase;
}

.cp-label {
  font-size: 0.95rem;
  font-weight: 700;
  margin: 2px 0;
  color: var(--text-main);
}

.cp-desc {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Right Column: Analytics & Control Tabs */
.right-column {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.tab-nav {
  display: flex;
  gap: 8px;
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 8px;
  margin-bottom: 12px;
}

.tab-btn {
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.2s;
}

.tab-btn.active {
  background: rgba(255, 255, 255, 0.1);
  color: var(--text-main);
}

.tab-btn:hover:not(.active) {
  color: var(--text-main);
}

/* Metric Cards */
.metrics-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 1rem;
}

.metric-box {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 10px 12px;
}

.metric-title {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-top: 4px;
}

.metric-delta {
  font-size: 0.75rem;
  color: var(--accent-green);
  display: flex;
  align-items: center;
  gap: 2px;
}

/* Charts */
.chart-container {
  position: relative;
  height: 220px;
  width: 100%;
}

/* Hyperparameters Control */
.control-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.control-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.control-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  display: flex;
  justify-content: space-between;
}

.control-label span.val {
  font-family: var(--font-mono);
  color: var(--accent-cyan);
}

input[type="range"] {
  width: 100%;
  accent-color: var(--accent-cyan);
  background: rgba(255, 255, 255, 0.1);
  height: 5px;
  border-radius: 5px;
  outline: none;
  cursor: pointer;
}

/* Comparison Grid Modal / View */
.comparison-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.compare-card {
  background: rgba(10, 14, 23, 0.6);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 10px;
}

.compare-canvas-box {
  height: 140px;
  width: 100%;
  background: #02050c;
  border-radius: var(--radius-sm);
  position: relative;
  overflow: hidden;
}

/* Modal */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(10px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 999;
}

.modal-backdrop.open {
  display: flex;
}

.modal-content {
  background: var(--bg-secondary);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  width: 90%;
  max-width: 900px;
  padding: 1.5rem;
  box-shadow: 0 0 50px rgba(0, 242, 254, 0.2);
}

.code-block {
  font-family: var(--font-mono);
  background: #060911;
  padding: 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  font-size: 0.85rem;
  color: #a5b4fc;
  max-height: 380px;
  overflow-y: auto;
  white-space: pre;
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 1000;
}

.toast {
  background: rgba(17, 25, 40, 0.95);
  border: 1px solid var(--accent-cyan);
  box-shadow: var(--shadow-glow);
  color: #fff;
  padding: 12px 18px;
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  display: flex;
  align-items: center;
  gap: 10px;
  animation: slideIn 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}
