/* RailSense-AI NOC Dashboard — Shared Design System */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@300;400;500;600;700&family=DM+Sans:wght@300;400;500;600;700&display=swap');

:root {
  /* Core palette — clean, professional light theme */
  --bg-primary: #f8f9fb;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f5f9;
  --bg-elevated: #f1f5f9;
  --border-subtle: #e2e8f0;
  --border-default: #cbd5e1;

  /* Text hierarchy */
  --text-primary: #1e293b;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-dim: #94a3b8;

  /* Severity system — bold, unambiguous */
  --critical: #dc2626;
  --critical-bg: #fef2f2;
  --critical-border: #fecaca;
  --critical-glow: rgba(220, 38, 38, 0.12);

  --warning: #d97706;
  --warning-bg: #fffbeb;
  --warning-border: #fde68a;

  --healthy: #059669;
  --healthy-bg: #ecfdf5;
  --healthy-border: #a7f3d0;

  --info: #2563eb;
  --info-bg: #eff6ff;
  --info-border: #bfdbfe;

  /* MRT line colors — official SMRT colors */
  --nsl-red: #d42e12;
  --ewl-green: #009645;
  --ccl-orange: #e88e00;
  --dtl-blue: #005ec4;
  --nel-purple: #8b5cf6;
  --tel-brown: #9d5b25;

  /* Accent */
  --accent: #2563eb;
  --accent-bg: #eff6ff;

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;

  /* Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  /* Fonts */
  --font-mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;
  --font-sans: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  -webkit-font-smoothing: antialiased;
}

/* ─── Layout Shell ─── */

.sidebar {
  width: 240px;
  min-height: 100vh;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-subtle);
  padding: var(--space-lg) 0;
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0;
  left: 0;
  z-index: 100;
  box-shadow: 1px 0 3px rgba(0, 0, 0, 0.04);
}

.sidebar-brand {
  padding: 0 var(--space-lg);
  margin-bottom: var(--space-2xl);
}

.sidebar-brand h1 {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: -0.5px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.sidebar-brand h1 .logo-icon {
  width: 28px;
  height: 28px;
  background: var(--accent);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  color: #ffffff;
}

.sidebar-brand .subtitle {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 4px;
  font-weight: 400;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.sidebar-nav {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 0 var(--space-sm);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: 10px var(--space-md);
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 13px;
  font-weight: 500;
  transition: all 0.15s ease;
  cursor: pointer;
}

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

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

.nav-item .nav-icon {
  font-size: 16px;
  width: 20px;
  text-align: center;
  opacity: 0.7;
}

.nav-item.active .nav-icon { opacity: 1; }

.sidebar-footer {
  padding: var(--space-md) var(--space-lg);
  border-top: 1px solid var(--border-subtle);
}

.system-status {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 11px;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--healthy);
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4); }
  50% { opacity: 0.7; box-shadow: 0 0 0 4px rgba(16, 185, 129, 0); }
}

/* ─── Main Content ─── */

.main-content {
  margin-left: 240px;
  flex: 1;
  min-height: 100vh;
  padding: var(--space-xl);
}

.page-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: var(--space-xl);
}

.page-header h2 {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.3px;
}

.page-header .page-subtitle {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 4px;
}

.header-time {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-muted);
  text-align: right;
}

.header-time .time-value {
  font-size: 18px;
  color: var(--text-primary);
  font-weight: 600;
  letter-spacing: -0.5px;
}

/* ─── Cards ─── */

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.card-title {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  margin-bottom: var(--space-md);
}

/* ─── Metric Cards ─── */

.metrics-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.metric-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  position: relative;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
}

.metric-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
}

.metric-card.critical::before { background: var(--critical); }
.metric-card.warning::before { background: var(--warning); }
.metric-card.healthy::before { background: var(--healthy); }
.metric-card.info::before { background: var(--info); }

.metric-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  margin-bottom: var(--space-sm);
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -1px;
  line-height: 1;
}

.metric-card.critical .metric-value { color: var(--critical); }
.metric-card.warning .metric-value { color: var(--warning); }
.metric-card.healthy .metric-value { color: var(--healthy); }
.metric-card.info .metric-value { color: var(--accent); }

.metric-delta {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: var(--space-sm);
  font-family: var(--font-mono);
}

/* ─── Tables ─── */

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

.data-table thead th {
  text-align: left;
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-muted);
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--border-default);
}

.data-table tbody td {
  padding: 10px var(--space-md);
  border-bottom: 1px solid var(--border-subtle);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-secondary);
}

.data-table tbody tr:hover {
  background: var(--bg-card-hover);
}

/* ─── Severity Badges ─── */

.severity-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-family: var(--font-mono);
}

.severity-badge.critical {
  background: var(--critical-bg);
  color: var(--critical);
  border: 1px solid var(--critical-border);
}

.severity-badge.warning {
  background: var(--warning-bg);
  color: var(--warning);
  border: 1px solid var(--warning-border);
}

.severity-badge.info {
  background: var(--info-bg);
  color: var(--info);
  border: 1px solid var(--info-border);
}

.severity-badge.healthy {
  background: var(--healthy-bg);
  color: var(--healthy);
  border: 1px solid var(--healthy-border);
}

/* ─── Buttons ─── */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 8px 16px;
  border-radius: var(--radius-md);
  font-size: 12px;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.15s ease;
}

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

.btn-primary:hover {
  background: #1d4ed8;
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: var(--border-default);
}

.btn-ghost:hover {
  background: var(--bg-card);
  color: var(--text-primary);
}

/* ─── Line Status Indicators ─── */

.line-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 20px;
  border-radius: 3px;
  font-size: 9px;
  font-weight: 700;
  font-family: var(--font-mono);
  color: white;
}

.line-badge.nsl { background: var(--nsl-red); }
.line-badge.ewl { background: var(--ewl-green); }
.line-badge.ccl { background: var(--ccl-orange); }
.line-badge.dtl { background: var(--dtl-blue); }
.line-badge.nel { background: var(--nel-purple); }
.line-badge.tel { background: var(--tel-brown); }

/* ─── Charts (placeholder styling) ─── */

.chart-container {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  position: relative;
}

.chart-placeholder {
  height: 280px;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 39px,
    rgba(0, 0, 0, 0.05) 39px,
    rgba(0, 0, 0, 0.05) 40px
  );
  border-radius: var(--radius-sm);
  position: relative;
  overflow: hidden;
}

/* ─── Animations ─── */

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate-in {
  animation: fadeIn 0.4s ease forwards;
}

.animate-in:nth-child(1) { animation-delay: 0.05s; }
.animate-in:nth-child(2) { animation-delay: 0.1s; }
.animate-in:nth-child(3) { animation-delay: 0.15s; }
.animate-in:nth-child(4) { animation-delay: 0.2s; }

/* ─── Scrollbar ─── */

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-default); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }