/* ═══════════════════════════════════════════
   CD ENGINEERING TOOLS — DESIGN SYSTEM v1.0
   Christian Delobelle | Transformation Industrielle
   ═══════════════════════════════════════════ */

/* ── VARIABLES ── */
:root {
  --bg-dark:      #0f1115;
  --bg-darker:    #050507;
  --surface:      #1a1d24;
  --surface-2:    #1f2330;
  --border:       rgba(255,255,255,0.06);
  --border-hover: rgba(255,255,255,0.15);

  --gold:         #c5a059;
  --gold-light:   #e2c078;
  --gold-dim:     rgba(197,160,89,0.15);
  --blue:         #3b82f6;
  --blue-dim:     rgba(59,130,246,0.12);
  --red:          #dc2626;
  --red-dim:      rgba(220,38,38,0.12);
  --green:        #16a34a;
  --green-dim:    rgba(22,163,74,0.12);
  --orange:       #ea580c;
  --orange-dim:   rgba(234,88,12,0.12);

  --text-primary:   #ffffff;
  --text-secondary: #9ca3af;
  --text-muted:     #6b7280;

  --font-title: 'Cinzel', serif;
  --font-body:  'Barlow', sans-serif;
  --font-mono:  'JetBrains Mono', monospace;

  --transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  --radius: 4px;
}

/* ── RESET ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  background: var(--bg-dark);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-weight: 400;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ── TEXTURE BACKGROUND ── */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(255,255,255,0.015) 1px, transparent 0);
  background-size: 28px 28px;
  pointer-events: none;
  z-index: 0;
}

/* ═══════════════════════════════════════════
   NAVIGATION
   ═══════════════════════════════════════════ */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(5,5,7,0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 1rem;
  text-decoration: none;
  cursor: pointer;
}

.nav-logo {
  width: 36px;
  height: 36px;
  border: 1px solid var(--gold);
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav-logo-text {
  font-family: var(--font-title);
  font-size: 0.85rem;
  color: var(--gold);
  font-weight: 600;
}

.nav-name {
  font-family: var(--font-title);
  font-size: 0.9rem;
  color: var(--text-primary);
  letter-spacing: 0.15em;
}

.nav-name span { color: var(--gold); font-weight: 400; }

.nav-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--border);
}

/* Nav back button (visible in calculator view) */
.nav-back {
  display: none;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  cursor: pointer;
  padding: 0.3rem 0.7rem;
  border: 1px solid var(--border);
  background: none;
  transition: var(--transition);
}

.nav-back:hover {
  color: var(--gold);
  border-color: rgba(197,160,89,0.4);
}

body.view-calculator .nav-back { display: flex; }
body.view-calculator .nav-tag  { display: none; }

/* ═══════════════════════════════════════════
   MAIN LAYOUT
   ═══════════════════════════════════════════ */
main {
  position: relative;
  z-index: 1;
  max-width: 1100px;
  margin: 0 auto;
  padding: 7rem 2rem 4rem;
}

/* ═══════════════════════════════════════════
   HUB — PAGE D'ACCUEIL
   ═══════════════════════════════════════════ */
.hub-hero {
  text-align: center;
  margin-bottom: 3rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid var(--border);
}

.hub-hero-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--gold);
  text-transform: uppercase;
  letter-spacing: 0.35em;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
}

.hub-hero-label::before,
.hub-hero-label::after {
  content: '';
  display: inline-block;
  width: 32px;
  height: 1px;
  background: var(--gold);
}

.hub-title {
  font-family: var(--font-title);
  font-size: 2.4rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: 0.06em;
  margin-bottom: 0.5rem;
}

.hub-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 300;
  margin-bottom: 2rem;
}

.hub-stats {
  display: flex;
  justify-content: center;
  gap: 2.5rem;
  margin-bottom: 2rem;
}

.hub-stat {
  text-align: center;
}

.hub-stat-value {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 500;
  color: var(--gold-light);
}

.hub-stat-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.15em;
  margin-top: 0.25rem;
}

/* Search bar */
.hub-search {
  position: relative;
  max-width: 500px;
  margin: 0 auto;
}

.hub-search-input {
  width: 100%;
  padding: 0.75rem 1rem 0.75rem 2.5rem;
  background: rgba(0,0,0,0.35);
  border: 1px solid rgba(255,255,255,0.1);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.92rem;
  border-radius: var(--radius);
  outline: none;
  transition: var(--transition);
}

.hub-search-input::placeholder {
  color: var(--text-muted);
}

.hub-search-input:focus {
  border-color: var(--gold);
  background: rgba(197,160,89,0.05);
  box-shadow: 0 0 0 2px rgba(197,160,89,0.1);
}

.hub-search-icon {
  position: absolute;
  left: 0.85rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 0.85rem;
  pointer-events: none;
}

/* Category navigation buttons */
.hub-cat-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.4rem;
  margin-top: 1.25rem;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.hub-cat-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.75rem;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 999px;
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: 0.72rem;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.hub-cat-btn:hover {
  background: rgba(197,160,89,0.1);
  border-color: rgba(197,160,89,0.3);
  color: var(--gold);
}

.hub-cat-btn.active {
  background: rgba(197,160,89,0.15);
  border-color: var(--gold);
  color: var(--gold);
}

.hub-category--flash {
  animation: catFlash 1.2s ease both;
}

@keyframes catFlash {
  0%   { border-left: 3px solid var(--gold); padding-left: 0.75rem; }
  100% { border-left: 3px solid transparent; padding-left: 0.75rem; }
}

/* Category sections */
.hub-category {
  margin-bottom: 2.5rem;
}

.hub-category-title {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
  font-family: var(--font-title);
  font-size: 1.3rem;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.hub-category-title::before {
  content: '';
  width: 24px;
  height: 1px;
  background: var(--gold);
}

.hub-category-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
}

.hub-category-count {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--gold);
  padding: 0.15rem 0.4rem;
  border: 1px solid rgba(197,160,89,0.3);
}

/* Calculator cards */
.hub-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}

.hub-card {
  background: var(--surface);
  border: 1px solid rgba(197,160,89,0.25);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  display: block;
}

.hub-card:hover {
  border-color: rgba(197,160,89,0.55);
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.3), 0 0 12px rgba(197,160,89,0.1);
}

.hub-card-title {
  font-family: var(--font-title);
  font-size: 0.85rem;
  color: var(--text-primary);
  letter-spacing: 0.05em;
  margin-bottom: 0.4rem;
}

.hub-card-desc {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-weight: 300;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

.hub-card-badges {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
}

.hub-card-badge {
  font-family: var(--font-mono);
  font-size: 0.58rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.15rem 0.45rem;
  border: 1px solid;
  color: var(--text-muted);
  border-color: var(--border);
}

/* No results */
.hub-no-results {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

/* ═══════════════════════════════════════════
   CALCULATOR — HEADER
   ═══════════════════════════════════════════ */
.calc-header {
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.calc-category {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--gold);
  text-transform: uppercase;
  letter-spacing: 0.35em;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.calc-category::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--gold);
}

.calc-title {
  font-family: var(--font-title);
  font-size: 2.2rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
  line-height: 1.2;
}

.calc-subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 300;
  max-width: 600px;
}

.calc-badges {
  display: flex;
  gap: 0.5rem;
  margin-top: 1rem;
  flex-wrap: wrap;
}

.badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  padding: 0.25rem 0.6rem;
  border: 1px solid;
}

.badge-norm  { color: var(--blue);   border-color: rgba(59,130,246,0.4); }
.badge-unit  { color: var(--gold);   border-color: rgba(197,160,89,0.4); }
.badge-dom   { color: var(--text-muted); border-color: var(--border); }

/* ═══════════════════════════════════════════
   CALCULATOR — GRID LAYOUTS
   ═══════════════════════════════════════════ */
.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.calc-grid-3 {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

/* ═══════════════════════════════════════════
   CALCULATOR — PANELS
   ═══════════════════════════════════════════ */
.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: var(--transition);
}

.panel:hover { border-color: var(--border-hover); }

.panel-title {
  font-family: var(--font-title);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.panel-title-icon {
  width: 6px;
  height: 6px;
  background: var(--gold);
  display: inline-block;
}

/* ═══════════════════════════════════════════
   CALCULATOR — INPUT COMPONENTS
   ═══════════════════════════════════════════ */
.input-group {
  margin-bottom: 1.1rem;
}

.input-group:last-child { margin-bottom: 0; }

.input-label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 0.4rem;
}

.input-label-text {
  font-size: 0.82rem;
  color: var(--text-secondary);
  font-weight: 400;
}

.input-label-unit {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--gold);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

input[type="number"], select {
  width: 100%;
  padding: 0.65rem 0.9rem;
  background: rgba(0,0,0,0.35);
  border: 1px solid rgba(255,255,255,0.1);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.92rem;
  border-radius: var(--radius);
  outline: none;
  transition: var(--transition);
  appearance: none;
}

input[type="number"]:focus, select:focus {
  border-color: var(--gold);
  background: rgba(197,160,89,0.05);
  box-shadow: 0 0 0 2px rgba(197,160,89,0.1);
}

input[type="number"]::-webkit-inner-spin-button { opacity: 0.4; }

select { cursor: pointer; padding-right: 2rem; }

.select-arrow {
  position: absolute;
  right: 0.75rem;
  pointer-events: none;
  color: var(--text-muted);
  font-size: 0.7rem;
}

/* Range slider */
.range-group { margin-bottom: 1.1rem; }

input[type="range"] {
  width: 100%;
  height: 3px;
  background: var(--surface-2);
  outline: none;
  border-radius: 2px;
  cursor: pointer;
  accent-color: var(--gold);
  margin-top: 0.5rem;
}

.range-labels {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-muted);
  margin-top: 0.3rem;
}

/* Divider */
.input-divider {
  height: 1px;
  background: var(--border);
  margin: 1rem 0;
}

/* Toggle group (radio-like buttons) */
.toggle-group {
  display: flex;
  gap: 0;
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 1.1rem;
}

.toggle-btn {
  flex: 1;
  padding: 0.5rem 0.5rem;
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: var(--transition);
  border-right: 1px solid rgba(255,255,255,0.1);
}

.toggle-btn:last-child { border-right: none; }

.toggle-btn.active {
  background: var(--gold-dim);
  color: var(--gold);
  font-weight: 600;
}

.toggle-btn:hover:not(.active) {
  background: rgba(255,255,255,0.04);
  color: var(--text-secondary);
}

/* ═══════════════════════════════════════════
   CALCULATOR — RESULTS
   ═══════════════════════════════════════════ */
.results-panel {
  background: var(--bg-darker);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
}

.result-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.85rem 1rem;
  border-radius: var(--radius);
  margin-bottom: 0.6rem;
  transition: var(--transition);
}

.result-item:last-child { margin-bottom: 0; }

.result-item.primary {
  background: var(--gold-dim);
  border: 1px solid rgba(197,160,89,0.25);
}

.result-item.secondary {
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--border);
}

.result-item.ok {
  background: var(--green-dim);
  border: 1px solid rgba(22,163,74,0.3);
}

.result-item.warning {
  background: var(--orange-dim);
  border: 1px solid rgba(234,88,12,0.3);
}

.result-item.danger {
  background: var(--red-dim);
  border: 1px solid rgba(220,38,38,0.3);
}

.result-label {
  font-size: 0.82rem;
  color: var(--text-secondary);
  font-weight: 400;
}

.result-item.primary .result-label { color: rgba(197,160,89,0.8); }
.result-item.ok      .result-label { color: rgba(22,163,74,0.8); }
.result-item.warning .result-label { color: rgba(234,88,12,0.8); }
.result-item.danger  .result-label { color: rgba(220,38,38,0.8); }

.result-value-group {
  display: flex;
  align-items: baseline;
  gap: 0.4rem;
}

.result-value {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 500;
  color: var(--text-primary);
}

.result-item.primary .result-value { color: var(--gold-light); font-size: 1.7rem; }
.result-item.ok      .result-value { color: #4ade80; }
.result-item.warning .result-value { color: #fb923c; }
.result-item.danger  .result-value { color: #f87171; }

.result-unit {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--text-muted);
  text-transform: uppercase;
}

/* ═══════════════════════════════════════════
   CALCULATOR — STATUS BAR
   ═══════════════════════════════════════════ */
.status-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 1rem;
  border-radius: var(--radius);
  margin-top: 1rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.status-bar.ok      { background: var(--green-dim);  color: #4ade80;  border: 1px solid rgba(22,163,74,0.3); }
.status-bar.warning { background: var(--orange-dim); color: #fb923c;  border: 1px solid rgba(234,88,12,0.3); }
.status-bar.danger  { background: var(--red-dim);    color: #f87171;  border: 1px solid rgba(220,38,38,0.3); }
.status-bar.neutral { background: var(--blue-dim);   color: #60a5fa;  border: 1px solid rgba(59,130,246,0.3); }

.status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.status-bar.ok      .status-dot { background: #4ade80; }
.status-bar.warning .status-dot { background: #fb923c; }
.status-bar.danger  .status-dot { background: #f87171; }
.status-bar.neutral .status-dot { background: #60a5fa; }

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.4; }
}

/* ═══════════════════════════════════════════
   CALCULATOR — SVG SCHEMA
   ═══════════════════════════════════════════ */
.schema-panel {
  background: var(--bg-darker);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  cursor: pointer;
  position: relative;
}

.schema-panel::after {
  content: '\26F6';
  position: absolute;
  top: 0.6rem;
  right: 0.8rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  opacity: 0;
  transition: opacity 0.2s;
}
.schema-panel:hover::after { opacity: 0.7; }

.schema-svg {
  width: 100%;
  max-width: 700px;
}

/* ── Lightbox plein \u00e9cran SVG ── */
.schema-lightbox {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0,0,0,0.92);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: zoom-out;
  animation: lbFadeIn 0.25s ease;
  padding: 2rem;
}
.schema-lightbox svg {
  max-width: 95vw;
  max-height: 90vh;
  width: auto;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 0 60px rgba(197,160,89,0.15);
}
.schema-lightbox-close {
  position: absolute;
  top: 1.2rem;
  right: 1.5rem;
  background: none;
  border: 1px solid rgba(255,255,255,0.2);
  color: #fff;
  font-size: 1.2rem;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}
.schema-lightbox-close:hover {
  background: rgba(255,255,255,0.1);
  border-color: var(--gold);
  color: var(--gold);
}
@keyframes lbFadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}

/* ═══════════════════════════════════════════
   CALCULATOR — FORMULAS
   ═══════════════════════════════════════════ */
.formula-section {
  margin-top: 1.5rem;
  padding: 1.25rem 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--gold);
  border-radius: var(--radius);
}

.formula-title {
  font-family: var(--font-title);
  font-size: 0.7rem;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.75rem;
}

.formula-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem 2rem;
}

.formula-item {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-secondary);
  padding: 0.3rem 0;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  gap: 0.5rem;
}

.formula-sym { color: var(--gold); font-weight: 500; }

/* ═══════════════════════════════════════════
   CALCULATOR — NOTES
   ═══════════════════════════════════════════ */
.note {
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  font-size: 0.8rem;
  line-height: 1.5;
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.note-info   { background: var(--blue-dim);   border: 1px solid rgba(59,130,246,0.2);  color: #93c5fd; }
.note-warn   { background: var(--orange-dim); border: 1px solid rgba(234,88,12,0.2);   color: #fdba74; }
.note-danger { background: var(--red-dim);    border: 1px solid rgba(220,38,38,0.2);   color: #fca5a5; }

.note-icon { flex-shrink: 0; font-size: 0.9rem; }

/* ═══════════════════════════════════════════
   SECTION SEPARATOR
   ═══════════════════════════════════════════ */
.section-sep {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 2rem 0 1.5rem;
  font-family: var(--font-title);
  font-size: 0.65rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.section-sep::before, .section-sep::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
}

/* ═══════════════════════════════════════════
   FOOTER
   ═══════════════════════════════════════════ */
footer {
  position: relative;
  z-index: 1;
  margin-top: 4rem;
  padding: 1.5rem 2rem;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1100px;
  margin-left: auto;
  margin-right: auto;
}

.footer-left {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.15em;
}

.footer-right {
  font-family: var(--font-title);
  font-size: 0.7rem;
  color: var(--gold);
  letter-spacing: 0.2em;
}

/* ═══════════════════════════════════════════
   ANIMATIONS
   ═══════════════════════════════════════════ */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

.calc-header     { animation: fadeUp 0.5s ease both; }
.calc-grid       { animation: fadeUp 0.5s ease 0.1s both; }
.calc-grid-3     { animation: fadeUp 0.5s ease 0.1s both; }
.formula-section { animation: fadeUp 0.5s ease 0.2s both; }
.hub-hero        { animation: fadeUp 0.5s ease both; }
.hub-category    { animation: fadeUp 0.5s ease 0.1s both; }

/* ═══════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════ */
@media (max-width: 768px) {
  .calc-grid, .calc-grid-3 { grid-template-columns: 1fr; }
  .calc-title { font-size: 1.6rem; }
  .hub-title  { font-size: 1.6rem; }
  .hub-stats  { gap: 1.5rem; }
  .hub-cards  { grid-template-columns: 1fr; }
  .formula-grid { grid-template-columns: 1fr; }
  nav { padding: 0.75rem 1rem; }
  main { padding: 5.5rem 1rem 3rem; }
}

/* ═══════════════════════════════════════════
   SCROLLBAR
   ═══════════════════════════════════════════ */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-darker); }
::-webkit-scrollbar-thumb { background: #333; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #555; }

/* ═══════════════════════════════════════════
   PDF EXPORT BUTTON (screen)
   ═══════════════════════════════════════════ */
.btn-export {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1rem;
  padding: 0.55rem 1.3rem;
  background: transparent;
  border: 1px solid rgba(197,160,89,0.4);
  color: var(--gold);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  cursor: pointer;
  transition: var(--transition);
  border-radius: var(--radius);
}
.btn-export:hover {
  background: rgba(197,160,89,0.12);
  border-color: var(--gold);
  box-shadow: 0 0 16px rgba(197,160,89,0.15);
}
.btn-export svg { width: 14px; height: 14px; }

/* ═══════════════════════════════════════════
   PDF PRINT OVERLAY (hidden on screen)
   ═══════════════════════════════════════════ */
#pdf-print-overlay {
  display: none;
}

/* ═══════════════════════════════════════════
   @media print — PDF EXPORT LAYOUT
   ═══════════════════════════════════════════ */
@media print {
  /* Hide everything except the overlay */
  body > *:not(#pdf-print-overlay) { display: none !important; }
  body {
    background: #ffffff !important;
    color: #1a1a1a !important;
    margin: 0 !important;
    padding: 0 !important;
  }
  body::before { display: none !important; }

  #pdf-print-overlay {
    display: block !important;
    position: static !important;
    background: #ffffff !important;
  }

  @page { size: A4 portrait; margin: 15mm 12mm; }

  /* ── Page layout ── */
  .pdf-page {
    max-width: 100%;
    padding: 0;
    font-family: 'Barlow', sans-serif;
    color: #1a1a1a;
    font-size: 10pt;
    line-height: 1.5;
  }

  /* ── Header ── */
  .pdf-header {
    text-align: center;
    padding-bottom: 10pt;
    border-bottom: 2px solid #c5a059;
    margin-bottom: 14pt;
  }
  .pdf-brand {
    font-family: 'Cinzel', serif;
    font-size: 8pt;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: #c5a059;
    margin-bottom: 4pt;
  }
  .pdf-title {
    font-family: 'Cinzel', serif;
    font-size: 18pt;
    font-weight: 600;
    color: #1a1a1a;
    margin: 0 0 4pt;
  }
  .pdf-subtitle {
    font-size: 10pt;
    color: #666666;
    font-weight: 300;
    margin: 0;
  }
  .pdf-badges {
    display: flex;
    justify-content: center;
    gap: 6pt;
    margin-top: 8pt;
    flex-wrap: wrap;
  }
  .pdf-badge {
    font-family: 'JetBrains Mono', monospace;
    font-size: 7pt;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 2pt 6pt;
    border: 1px solid;
    border-radius: 2px;
  }
  .pdf-badge-norm { color: #2563eb; border-color: #93c5fd; }
  .pdf-badge-unit { color: #92400e; border-color: #c5a059; }
  .pdf-badge-dom  { color: #6b7280; border-color: #d1d5db; }

  /* ── Sections ── */
  .pdf-section {
    margin-bottom: 14pt;
    page-break-inside: avoid;
  }
  .pdf-section-title {
    font-family: 'Cinzel', serif;
    font-size: 10pt;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: #c5a059;
    padding-bottom: 4pt;
    border-bottom: 1px solid #e5e7eb;
    margin-bottom: 8pt;
  }

  /* ── Tables (inputs & results) ── */
  .pdf-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 9pt;
    margin-bottom: 8pt;
  }
  .pdf-table th {
    text-align: left;
    font-family: 'JetBrains Mono', monospace;
    font-size: 7pt;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #6b7280;
    padding: 4pt 8pt;
    border-bottom: 1px solid #d1d5db;
  }
  .pdf-table td {
    padding: 4pt 8pt;
    border-bottom: 1px solid #f3f4f6;
  }
  .pdf-td-label { color: #374151; }
  .pdf-td-value {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 500;
    color: #1a1a1a;
    text-align: right;
  }
  .pdf-td-unit {
    font-family: 'JetBrains Mono', monospace;
    font-size: 8pt;
    color: #9ca3af;
    width: 60pt;
  }

  /* ── Primary & status result rows ── */
  .pdf-row-primary { background: #fef9ee; font-weight: 600; }
  .pdf-row-primary .pdf-td-value { color: #92400e; }
  .pdf-status-ok td       { color: #166534; }
  .pdf-status-warning td  { color: #92400e; }
  .pdf-status-danger td   { color: #991b1b; }

  /* ── Status bar ── */
  .pdf-status-bar {
    font-family: 'JetBrains Mono', monospace;
    font-size: 8pt;
    padding: 6pt 10pt;
    border-radius: 3px;
    margin-top: 6pt;
    text-transform: uppercase;
    letter-spacing: 0.05em;
  }
  .pdf-status-bar.pdf-status-ok      { background: #f0fdf4; color: #166534; border: 1px solid #bbf7d0; }
  .pdf-status-bar.pdf-status-warning { background: #fff7ed; color: #92400e; border: 1px solid #fed7aa; }
  .pdf-status-bar.pdf-status-danger  { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
  .pdf-status-bar.pdf-status-neutral { background: #f5f5f5; color: #374151; border: 1px solid #e5e7eb; }

  /* ── Schema SVG ── */
  .pdf-schema {
    text-align: center;
    margin: 10pt auto;
    max-width: 100%;
    background: #ffffff;
    border: 1px solid #e5e7eb;
    border-radius: 4pt;
    padding: 12pt;
  }
  .pdf-schema svg {
    width: 100%;
    height: auto;
    filter: invert(1) hue-rotate(180deg);
  }

  /* ── Results group ── */
  .pdf-results-group { margin-bottom: 10pt; }
  .pdf-group-title {
    font-family: 'Cinzel', serif;
    font-size: 8pt;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: #6b7280;
    margin-bottom: 4pt;
  }

  /* ── Formulas ── */
  .pdf-formula-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2pt 16pt;
  }
  .pdf-formula-item {
    font-family: 'JetBrains Mono', monospace;
    font-size: 8pt;
    color: #374151;
    padding: 3pt 0;
    border-bottom: 1px solid #f3f4f6;
    display: flex;
    gap: 6pt;
  }
  .pdf-formula-sym { color: #92400e; font-weight: 500; white-space: nowrap; }

  /* ── Notes ── */
  .pdf-note {
    padding: 5pt 8pt;
    border-radius: 3px;
    font-size: 8pt;
    line-height: 1.5;
    display: flex;
    gap: 6pt;
    align-items: flex-start;
    margin-bottom: 4pt;
  }
  .pdf-note-info   { background: #eff6ff; border: 1px solid #bfdbfe; color: #1e40af; }
  .pdf-note-warn   { background: #fff7ed; border: 1px solid #fed7aa; color: #92400e; }
  .pdf-note-danger { background: #fef2f2; border: 1px solid #fecaca; color: #991b1b; }
  .pdf-note-icon   { flex-shrink: 0; }

  /* ── Footer ── */
  .pdf-footer {
    margin-top: 16pt;
    padding-top: 8pt;
    border-top: 1px solid #e5e7eb;
    text-align: center;
    font-family: 'JetBrains Mono', monospace;
    font-size: 7pt;
    color: #9ca3af;
    letter-spacing: 0.08em;
  }
}