frontend/src/index.css

:root {
  /* NETRA command-center palette — deep navy canvas, cyan/blue accents */
  --bg: #070d18;
  --surface: #0e1a2d;
  --surface-2: #0a1626;
  --panel-grad: linear-gradient(180deg, rgba(255, 255, 255, 0.035), rgba(255, 255, 255, 0) 38%);
  --border: rgba(132, 168, 222, 0.13);
  --border-strong: rgba(132, 168, 222, 0.26);
  --text: #eaf1fb;
  --muted: #9fb4d2;
  --faint: #647a9c;

  /* Accent + status hues */
  --accent: #3b9eff;
  --accent-deep: #2b7fe0;
  --accent-soft: rgba(59, 158, 255, 0.13);
  --cyan: #2dd4e8;
  --violet: #a78bfa;
  --danger: #fb5e73;
  --danger-soft: rgba(251, 94, 115, 0.14);
  --warning: #fbb540;
  --warning-soft: rgba(251, 181, 64, 0.13);
  --success: #36d39a;
  --success-soft: rgba(54, 211, 154, 0.12);

  /* Blueprint grid line */
  --grid: rgba(255, 255, 255, 0.022);

  /* Radii */
  --r-sm: 9px;
  --r: 14px;
  --r-lg: 18px;

  /* Deep control-room shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow: 0 18px 40px -28px rgba(0, 0, 0, 0.85);
  --shadow-lg: 0 40px 120px -40px rgba(0, 0, 0, 0.85);

  --ring: 0 0 0 3px rgba(59, 158, 255, 0.22);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);

  --serif: "Inter", system-ui, -apple-system, sans-serif;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", monospace;
}

/* Toggle "dark" = an even deeper NETRA night; both stay command-center. */
[data-theme="dark"] {
  --bg: #05080f;
  --surface: #0c1626;
  --surface-2: #081120;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background-color: var(--bg);
  /* Navy glows + faint blueprint grid — the NETRA command-center canvas. */
  background-image:
    radial-gradient(1100px 520px at 86% -8%, rgba(40, 120, 200, 0.16), transparent 60%),
    radial-gradient(900px 600px at 6% 108%, rgba(45, 160, 180, 0.08), transparent 55%),
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 46px 46px, 46px 46px;
  background-attachment: fixed;
  color: var(--text);
  font-family: var(--sans);
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  line-height: 1.55;
}

h1, h2, h3, h4 {
  font-family: var(--sans);
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--text);
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

::selection {
  background: var(--accent-soft);
}

/* Entrance animation + stagger helper */
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.rise {
  animation: rise 0.5s var(--ease) both;
}

/* Thin, tasteful scrollbar */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 999px;
  border: 3px solid var(--bg);
}

/* SensorFusion & Signed Provenance */
.signed {
  margin-top: auto;
  background: rgba(54, 211, 154, 0.06);
  border: 1px solid rgba(54, 211, 154, 0.2);
  border-radius: 11px;
  padding: 12px 14px;
}
.signed .s1 {
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 7px;
}
.signed .s2 {
  font-size: 10.5px;
  color: var(--muted);
  font-family: 'JetBrains Mono', monospace;
  margin-top: 6px;
  line-height: 1.4;
}

.sf {
  display: flex;
  flex-direction: column;
}
.sf-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}
.sf-title {
  font-size: 13px;
  font-weight: 700;
}
.concept-tag {
  font-size: 9px;
  font-weight: 800;
  letter-spacing: 0.05em;
  background: var(--surface-2);
  color: var(--muted);
  padding: 2px 6px;
  border-radius: 4px;
}
.sf-thumbs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  height: 96px;
  margin-bottom: 12px;
}
.sf-thumb {
  border: 1px solid var(--border);
  border-radius: 11px;
  overflow: hidden;
  position: relative;
  display: flex;
  flex-direction: column;
}
.sf-thumb svg {
  display: block;
  width: 100%;
  flex: 1;
}
.sf-cap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 9px;
  background: #091421;
}
.sf-tag {
  font-size: 9.5px;
  font-weight: 800;
  letter-spacing: 0.05em;
  padding: 2px 7px;
  border-radius: 6px;
}
.sf-met {
  font-size: 9.5px;
}
.sf-bars {
  margin-bottom: 12px;
}