:root {
  --color-bg: #0a0e14;
  /* Deep technical dark */
  --color-bg-secondary: #161b22;
  --color-text: #e6edf3;
  --color-text-muted: #8b949e;
  --color-accent: #2f81f7;
  /* Nitrogen Blue - Science/Trust */
  --color-danger: #f85149;
  /* Alert Red - Hazards */
  --color-warning: #d29922;
  /* Warning Yellow - Caution */
  --color-success: #3fb950;
  /* Green - Safe alternatives */
  --color-border: #30363d;

  --font-heading: 'JetBrains Mono', 'Fira Code', monospace;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;

  --max-width: 1200px;
  --spacing-unit: 1rem;
}

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

body {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 2.5rem;
  line-height: 1.2;
}

h2 {
  font-size: 2rem;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 0.5rem;
  margin-top: 2rem;
}

h3 {
  font-size: 1.5rem;
  color: var(--color-text);
  margin-top: 1.5rem;
}

p {
  margin-bottom: 1.2rem;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s;
}

a:hover {
  color: #58a6ff;
  text-decoration: underline;
}

/* Layout */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-unit);
}

header {
  background-color: var(--color-bg-secondary);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--color-danger);
  border: 1px solid var(--color-danger);
  padding: 0.2rem 0.5rem;
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-text);
}

main {
  padding: 4rem 0;
}

footer {
  background-color: var(--color-bg-secondary);
  padding: 3rem 0;
  margin-top: 4rem;
  border-top: 1px solid var(--color-border);
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.8rem;
}

/* Components */
.btn {
  display: inline-block;
  background-color: var(--color-bg-secondary);
  color: var(--color-accent);
  border: 1px solid var(--color-border);
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.btn:hover {
  border-color: var(--color-text-muted);
  background-color: #21262d;
}

.btn-primary {
  background-color: var(--color-accent);
  color: white;
  border: none;
}

.btn-primary:hover {
  background-color: #1f6feb;
  color: white;
  text-decoration: none;
}

.alert {
  padding: 1rem;
  border-radius: 6px;
  margin-bottom: 1.5rem;
  border: 1px solid transparent;
}

.alert-danger {
  background-color: rgba(248, 81, 73, 0.1);
  border-color: rgba(248, 81, 73, 0.4);
  color: #ff7b72;
}

.alert-warning {
  background-color: rgba(210, 153, 34, 0.1);
  border-color: rgba(210, 153, 34, 0.4);
  color: #e3b341;
}

.card {
  background-color: var(--color-bg-secondary);
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

/* Diagrams/Animations */
.diagram-container {
  background-color: #010409;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  padding: 2rem;
  margin: 2rem 0;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 300px;
  position: relative;
  overflow: hidden;
}

.hero {
  text-align: center;
  padding: 6rem 0;
}

.hero h1 {
  font-size: 3.5rem;
  margin-bottom: 1.5rem;
  background: linear-gradient(to right, var(--color-danger), #ffb2ad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero p {
  font-size: 1.25rem;
  color: var(--color-text-muted);
  max-width: 800px;
  margin: 0 auto 2rem;
}

/* Utils */
.text-danger {
  color: var(--color-danger);
}

.text-warning {
  color: var(--color-warning);
}

.text-accent {
  color: var(--color-accent);
}

.mono {
  font-family: var(--font-heading);
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    /* Mobile menu implementation TODO */
  }

  .hero h1 {
    font-size: 2.5rem;
  }
}

/* Animations Phase 2 */
@keyframes shake {
  0% {
    transform: translate(1px, 1px) rotate(0deg);
  }

  10% {
    transform: translate(-1px, -2px) rotate(-1deg);
  }

  20% {
    transform: translate(-3px, 0px) rotate(1deg);
  }

  30% {
    transform: translate(3px, 2px) rotate(0deg);
  }

  40% {
    transform: translate(1px, -1px) rotate(1deg);
  }

  50% {
    transform: translate(-1px, 2px) rotate(-1deg);
  }

  60% {
    transform: translate(-3px, 1px) rotate(0deg);
  }

  70% {
    transform: translate(3px, 1px) rotate(-1deg);
  }

  80% {
    transform: translate(-1px, -1px) rotate(1deg);
  }

  90% {
    transform: translate(1px, 2px) rotate(0deg);
  }

  100% {
    transform: translate(1px, -2px) rotate(-1deg);
  }
}

@keyframes pulse-red {
  0% {
    filter: drop-shadow(0 0 2px rgba(248, 81, 73, 0.4));
  }

  50% {
    filter: drop-shadow(0 0 10px rgba(248, 81, 73, 0.8));
  }

  100% {
    filter: drop-shadow(0 0 2px rgba(248, 81, 73, 0.4));
  }
}

@keyframes flow {
  0% {
    stroke-dashoffset: 20;
  }

  100% {
    stroke-dashoffset: 0;
  }
}

.shaking {
  animation: shake 0.5s cubic-bezier(.36, .07, .19, .97) infinite;
}

.pulsing-red {
  animation: pulse-red 1.5s infinite;
}

.particle {
  transition: transform 0.1s linear;
}

/* Heat Slider UI */
.slider-container {
  padding: 1rem;
  background: #161b22;
  border: 1px solid var(--color-border);
  margin-top: 1rem;
  border-radius: 6px;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.heat-slider {
  -webkit-appearance: none;
  width: 100%;
  height: 8px;
  background: linear-gradient(to right, #2f81f7, #f85149);
  border-radius: 4px;
  outline: none;
}

.heat-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 20px;
  height: 20px;
  background: #e6edf3;
  cursor: pointer;
  border-radius: 50%;
}

.gauge-red {
  fill: #f85149;
  transition: height 0.2s;
}

/* Hazard Pulse */
.hazard-pulse {
  animation: pulse-red 2s infinite;
  cursor: pointer;
}