:root {
  --bg-primary: #0a0f1a;
  --bg-secondary: #111827;
  --bg-tertiary: #1f2937;
  --bg-card: #172033;
  --accent-primary: #38bdf8;
  --accent-secondary: #818cf8;
  --accent-warm: #fb923c;
  --accent-cool: #22d3ee;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border-color: #334155;
  --success: #4ade80;
  --warning: #fbbf24;
  --danger: #f87171;

  --font-sans: 'DM Sans', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;

  --shadow-glow: 0 0 40px rgba(56, 189, 248, 0.15);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.3);
}

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

html {
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  background-image:
    radial-gradient(ellipse at 20% 0%, rgba(56, 189, 248, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 100%, rgba(129, 140, 248, 0.08) 0%, transparent 50%);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
}

header {
  text-align: center;
  margin-bottom: 3rem;
  padding: 2rem 0;
}

h1 {
  font-size: 3rem;
  font-weight: 600;
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.125rem;
  font-weight: 300;
}

main {
  display: grid;
  gap: 2rem;
}

.controls-panel {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.control-group {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-card);
}

.control-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
}

.control-header label {
  font-weight: 500;
  color: var(--text-secondary);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.value-display {
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
}

.value-display .value {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 500;
  color: var(--accent-primary);
}

.value-display .unit {
  font-size: 1rem;
  color: var(--text-secondary);
}

.value-display .secondary-value {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-left: 0.5rem;
}

.slider-container {
  margin-bottom: 1rem;
}

input[type="range"] {
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: var(--bg-tertiary);
  appearance: none;
  cursor: pointer;
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-primary);
  cursor: grab;
  box-shadow: 0 2px 8px rgba(56, 189, 248, 0.4);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.1);
  box-shadow: 0 2px 16px rgba(56, 189, 248, 0.6);
}

input[type="range"]::-webkit-slider-thumb:active {
  cursor: grabbing;
  transform: scale(0.95);
}

input[type="range"]::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-primary);
  cursor: grab;
  border: none;
  box-shadow: 0 2px 8px rgba(56, 189, 248, 0.4);
}

.slider-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 0.5rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.control-buttons {
  display: flex;
  gap: 0.5rem;
}

.btn-adjust {
  flex: 1;
  padding: 0.625rem 1rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 1rem;
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-adjust:hover {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
  color: var(--bg-primary);
}

.btn-adjust:active {
  transform: scale(0.98);
}

.result-panel {
  background: linear-gradient(135deg, var(--bg-card) 0%, rgba(56, 189, 248, 0.05) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-card), var(--shadow-glow);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  align-items: center;
}

.dew-point-display {
  text-align: center;
}

.dew-point-label {
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.dew-point-value {
  font-family: var(--font-mono);
  font-size: 4rem;
  font-weight: 500;
  color: var(--accent-cool);
  line-height: 1;
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 0.25rem;
}

.dew-unit {
  font-size: 1.5rem;
  color: var(--text-secondary);
}

.dew-point-secondary {
  font-size: 1.125rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
}

.comfort-indicator {
  padding: 1rem;
}

.comfort-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}

.comfort-bar {
  position: relative;
  height: 12px;
  background: linear-gradient(90deg,
    #3b82f6 0%,
    #22c55e 25%,
    #eab308 50%,
    #f97316 75%,
    #ef4444 100%
  );
  border-radius: 6px;
  margin-bottom: 0.5rem;
}

.comfort-zones {
  display: flex;
  justify-content: space-between;
  padding-top: 1rem;
  font-size: 0.625rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.zone {
  color: var(--text-muted);
}

.comfort-marker {
  position: absolute;
  top: -4px;
  width: 20px;
  height: 20px;
  background: var(--text-primary);
  border: 3px solid var(--bg-primary);
  border-radius: 50%;
  transform: translateX(-50%);
  transition: left 0.3s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.comfort-text {
  text-align: center;
  font-weight: 500;
  font-size: 1rem;
  margin-top: 1rem;
  padding: 0.5rem 1rem;
  background: var(--bg-tertiary);
  border-radius: var(--radius-sm);
}

.spread-display {
  padding: 1rem;
  background: var(--bg-tertiary);
  border-radius: var(--radius-md);
}

.spread-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
}

.spread-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.spread-value {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--accent-warm);
}

.spread-description {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.visualization-panel {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 1.5rem;
}

.chart-container {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-card);
}

.chart-container h3 {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 1rem;
  text-align: center;
}

canvas {
  width: 100% !important;
  height: 250px !important;
}

.explanation-panel {
  margin-top: 2rem;
}

.explanation-panel h2 {
  font-size: 1.75rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

.explanation-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-card);
}

.card-icon {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}

.card h4 {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--accent-primary);
}

.card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.formula-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
}

.formula-box h4 {
  font-size: 1rem;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.formula-box p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 0.75rem;
}

.formula-box code {
  display: block;
  background: var(--bg-primary);
  border-radius: var(--radius-sm);
  padding: 1rem;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--accent-cool);
  line-height: 1.8;
  margin-bottom: 0.75rem;
}

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

footer {
  margin-top: 3rem;
  padding: 2rem 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
}

footer p {
  color: var(--text-muted);
  font-size: 0.875rem;
}

@media (max-width: 768px) {
  .container {
    padding: 1rem;
  }

  h1 {
    font-size: 2rem;
  }

  .dew-point-value {
    font-size: 3rem;
  }

  .visualization-panel {
    grid-template-columns: 1fr;
  }

  .chart-container {
    min-width: 0;
  }

  canvas {
    height: 200px !important;
  }
}

.comfort-text.dry { color: #3b82f6; }
.comfort-text.comfortable { color: #22c55e; }
.comfort-text.humid { color: #eab308; }
.comfort-text.very-humid { color: #f97316; }
.comfort-text.oppressive { color: #ef4444; }