/* Style for O sută cincizeci de mililitri / One Hundred and Fifty Millilitres */
:root {
  --bg-primary: #080c15;
  --bg-surface: #0f172a;
  --bg-surface-elevated: #1e293b;
  --bg-surface-subtle: rgba(30, 41, 59, 0.6);
  --border-subtle: rgba(56, 189, 248, 0.15);
  --border-focus: #38bdf8;
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  
  --color-fresh: #38bdf8;
  --color-deadspace: #818cf8;
  --color-alveolar: #f43f5e;
  --color-accent: #34d399;
  --color-warning: #fbbf24;
  
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: "SF Mono", Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  
  --max-width: 860px;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

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

html {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  overflow-x: hidden;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0;
  margin: 0;
  overflow-x: hidden;
  width: 100%;
}

/* Header & Nav */
.site-header {
  width: 100%;
  border-bottom: 1px solid var(--border-subtle);
  background: rgba(8, 12, 21, 0.85);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-secondary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: color 0.15s ease;
}

.brand-link:hover {
  color: var(--text-primary);
}

.lang-switch {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
}

.lang-link {
  color: var(--text-secondary);
  text-decoration: none;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: all 0.15s ease;
}

.lang-link:hover {
  color: var(--text-primary);
  border-color: var(--border-subtle);
}

.lang-link.active {
  color: var(--color-fresh);
  background: rgba(56, 189, 248, 0.1);
  border-color: rgba(56, 189, 248, 0.3);
  font-weight: 600;
}

/* Main Container */
main {
  width: 100%;
  max-width: var(--max-width);
  padding: 40px 20px 80px;
  display: flex;
  flex-direction: column;
  gap: 48px;
}

/* Hero Section (Answer-First) */
.hero {
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border-subtle);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--color-fresh);
  background: rgba(56, 189, 248, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.25);
  padding: 6px 14px;
  border-radius: 9999px;
  width: fit-content;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--color-fresh);
  box-shadow: 0 0 8px var(--color-fresh);
}

h1 {
  font-size: clamp(32px, 5vw, 44px);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.5px;
  color: var(--text-primary);
}

.lead {
  font-size: 19px;
  line-height: 1.6;
  color: #cbd5e1;
  font-weight: 400;
}

/* Key Metrics Grid */
.metrics-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-top: 10px;
}

.metric-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.metric-card:hover {
  border-color: rgba(56, 189, 248, 0.4);
  transform: translateY(-2px);
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 800;
  line-height: 1.1;
}

.metric-card.fresh .metric-value { color: var(--color-fresh); }
.metric-card.deadspace .metric-value { color: var(--color-deadspace); }
.metric-card.asphyxia .metric-value { color: var(--color-alveolar); }
.metric-card.gain .metric-value { color: var(--color-accent); }

.metric-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.metric-sub {
  font-size: 13px;
  color: var(--text-muted);
}

/* Content Sections */
.article-section {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.3;
  margin-top: 12px;
}

h3 {
  font-size: 19px;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
  margin-top: 8px;
}

p {
  color: #cbd5e1;
}

strong {
  color: var(--text-primary);
  font-weight: 600;
}

em {
  color: var(--text-primary);
  font-style: italic;
}

/* Visual Canvas & Airway Tree Interactive */
.interactive-container {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: relative;
}

.interactive-header {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.canvas-wrapper {
  width: 100%;
  height: 380px;
  background: #060911;
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-md);
  position: relative;
  overflow: hidden;
}

canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.canvas-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
  color: var(--text-secondary);
  padding: 4px 0;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.legend-color {
  width: 12px;
  height: 12px;
  border-radius: 3px;
}

.legend-fresh { background: var(--color-fresh); }
.legend-deadspace { background: var(--color-deadspace); }
.legend-alveolar { background: var(--color-alveolar); }

/* Controls & Sliders */
.controls-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  background: var(--bg-surface-elevated);
  padding: 20px;
  border-radius: var(--radius-md);
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.control-label-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}

.control-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
}

.control-value {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--color-fresh);
}

input[type="range"] {
  width: 100%;
  height: 6px;
  -webkit-appearance: none;
  appearance: none;
  background: #334155;
  border-radius: 3px;
  outline: none;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--color-fresh);
  cursor: pointer;
  box-shadow: 0 0 8px rgba(56, 189, 248, 0.6);
  transition: transform 0.1s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border: none;
  border-radius: 50%;
  background: var(--color-fresh);
  cursor: pointer;
  box-shadow: 0 0 8px rgba(56, 189, 248, 0.6);
}

/* Results Display Panel */
.results-panel {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  background: #0a0f1d;
  border: 1px solid rgba(56, 189, 248, 0.2);
  border-radius: var(--radius-md);
  padding: 18px 20px;
}

.result-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.result-title {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.result-val {
  font-family: var(--font-mono);
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
}

.result-val.danger { color: var(--color-alveolar); }
.result-val.success { color: var(--color-accent); }
.result-val.primary { color: var(--color-fresh); }

.result-desc {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Data Table */
.table-wrapper {
  width: 100%;
  overflow-x: auto;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  background: var(--bg-surface);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  text-align: left;
}

th {
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  font-weight: 600;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-subtle);
  white-space: nowrap;
}

td {
  padding: 12px 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  color: var(--text-secondary);
}

tr:last-child td {
  border-bottom: none;
}

td.num, th.num {
  text-align: right;
  font-family: var(--font-mono);
}

tr.highlight-row {
  background: rgba(56, 189, 248, 0.06);
}

tr.highlight-danger {
  background: rgba(244, 63, 94, 0.08);
}

/* Callout / Method Box */
.method-box {
  background: var(--bg-surface);
  border-left: 3px solid var(--color-fresh);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.method-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-fresh);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Self-Test Box */
.test-box {
  background: linear-gradient(145deg, #0d1527 0%, #131c33 100%);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.test-badge {
  color: var(--color-fresh);
  font-family: var(--font-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.test-btn {
  padding: 12px 24px;
  background: var(--color-fresh);
  color: #090d16;
  font-size: 15px;
  font-weight: 700;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  width: fit-content;
  transition: opacity 0.15s ease, transform 0.1s ease;
}

.test-btn:hover {
  opacity: 0.92;
  transform: translateY(-1px);
}

.test-btn:active {
  transform: translateY(0);
}

/* Footer */
footer {
  width: 100%;
  border-top: 1px solid var(--border-subtle);
  background: #060911;
  padding: 40px 20px;
  margin-top: auto;
}

.footer-content {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 20px;
  font-size: 14px;
  color: var(--text-muted);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

.footer-links a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.15s;
}

.footer-links a:hover {
  color: var(--color-fresh);
}

.sources-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
  padding-left: 0;
}

.sources-list li {
  color: var(--text-secondary);
}

.sources-list a {
  color: var(--color-fresh);
  text-decoration: none;
}

.sources-list a:hover {
  text-decoration: underline;
}

/* Reduced Motion Mode */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto !important;
  }
  *, *::before, *::after {
    animation-duration: 0.001s !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001s !important;
  }
}

/* Mobile Responsiveness */
@media (max-width: 640px) {
  main {
    padding: 24px 16px 60px;
    gap: 36px;
  }
  
  .metrics-strip {
    grid-template-columns: 1fr;
  }
  
  .canvas-wrapper {
    height: 280px;
  }
  
  .controls-grid {
    grid-template-columns: 1fr;
    padding: 16px;
  }
  
  .results-panel {
    grid-template-columns: 1fr;
  }
}