/* ─── Design Tokens ─── */
:root {
  --bg-primary: #0a0a0a;
  --bg-secondary: #111111;
  --bg-card: #161616;
  --bg-card-hover: #1a1a1a;
  --border-subtle: #1e1e1e;
  --border-accent: #2a2a2a;
  --text-primary: #f0f0f0;
  --text-secondary: #999999;
  --text-muted: #666666;
  --accent: #00e5a0;
  --accent-dim: #00c98b;
  --accent-glow: rgba(0, 229, 160, 0.12);
  --accent-glow-strong: rgba(0, 229, 160, 0.25);
  --danger: #ff4d4d;
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

::selection {
  background: var(--accent);
  color: var(--bg-primary);
}

/* ─── Scroll Bar ─── */
::-webkit-scrollbar {
  width: 6px;
}
::-webkit-scrollbar-track {
  background: var(--bg-primary);
}
::-webkit-scrollbar-thumb {
  background: var(--border-accent);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ─── Offset for fixed nav ─── */
section[id] {
  scroll-margin-top: 80px;
}

/* ─── Animations ─── */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulseGlow {
  0%, 100% {
    box-shadow: 0 0 20px var(--accent-glow);
  }
  50% {
    box-shadow: 0 0 40px var(--accent-glow-strong);
  }
}

.animate-fade-in-up {
  opacity: 0;
  animation: fadeInUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.animate-pulse-glow {
  animation: pulseGlow 3s ease-in-out infinite;
}

.animation-delay-100 { animation-delay: 0.1s; }
.animation-delay-200 { animation-delay: 0.2s; }
.animation-delay-300 { animation-delay: 0.3s; }
.animation-delay-400 { animation-delay: 0.4s; }

/* Observers will add this class to trigger entrance */
.observe-enter {
  opacity: 0;
  transition: all 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

.observe-translate-y {
  transform: translateY(24px);
}

.observe-translate-y-32 {
  transform: translateY(32px);
}

.observe-translate-y-40 {
  transform: translateY(40px);
}

.observe-enter.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ─── Geometric Background Pattern ─── */
.bg-grid-pattern {
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 60px 60px;
}

.bg-dots-pattern {
  background-image: radial-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px);
  background-size: 24px 24px;
}

/* ─── Card Styles ─── */
.card-industrial {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.card-industrial:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-accent);
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
}

/* ─── Timeline ─── */
.timeline-line {
  position: relative;
}

.timeline-line::before {
  content: '';
  position: absolute;
  left: 23px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(
    to bottom,
    var(--border-subtle),
    var(--accent),
    var(--border-subtle)
  );
}

@media (min-width: 768px) {
  .timeline-line::before {
    left: 50%;
    transform: translateX(-50%);
  }
}

/* ─── Utility ─── */
.text-gradient {
  background: linear-gradient(135deg, var(--accent) 0%, #00b87a 50%, #00d4aa 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}