/* ==========================================================================
   MATEMATICA NELLA DIVINA COMMEDIA - LABORATORIO STEM
   Design System, Tipografia, Palette Rinascimentale-Cosmica e Layout
   ========================================================================== */

:root {
  /* Palette Colori */
  --bg-dark: #07090e;
  --bg-surface: #0e1320;
  --bg-card: rgba(18, 26, 43, 0.85);
  --bg-card-hover: rgba(26, 37, 62, 0.95);
  --border-subtle: rgba(212, 175, 55, 0.2);
  --border-active: rgba(212, 175, 55, 0.7);
  
  /* Accenti */
  --gold-primary: #d4af37;
  --gold-light: #fbe083;
  --gold-dark: #997c1d;
  --gold-glow: rgba(212, 175, 55, 0.35);
  
  --celestial-blue: #38bdf8;
  --celestial-glow: rgba(56, 189, 248, 0.3);
  --mystic-purple: #a855f7;
  --inferno-crimson: #f43f5e;
  --inferno-glow: rgba(244, 63, 94, 0.3);
  --emerald-purgatory: #10b981;
  
  /* Testi */
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-terzina: #fef08a;
  
  /* Tipografia */
  --font-serif: 'Cinzel', 'Cinzel Decorative', Georgia, serif;
  --font-poetic: 'Cormorant Garamond', Garamond, 'Times New Roman', serif;
  --font-sans: 'Outfit', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
  
  /* Effetti e Ombre */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.5);
  --shadow-gold: 0 0 25px rgba(212, 175, 55, 0.25);
  --glass-blur: blur(14px);
  --transition-smooth: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  color-scheme: dark;
}

body {
  background-color: var(--bg-dark);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(56, 189, 248, 0.07) 0%, transparent 40%),
    radial-gradient(circle at 85% 20%, rgba(212, 175, 55, 0.08) 0%, transparent 45%),
    radial-gradient(circle at 50% 85%, rgba(168, 85, 247, 0.06) 0%, transparent 50%),
    linear-gradient(to bottom, #07090e 0%, #0a0e18 100%);
  background-attachment: fixed;
}

/* Container principale */
.app-container {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Header & Navbar */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  background: rgba(11, 15, 25, 0.88);
  border-bottom: 1px solid var(--border-subtle);
  padding: 0.75rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.brand-wrapper {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.brand-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, var(--gold-light), var(--gold-dark));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  color: #000;
  box-shadow: 0 0 16px var(--gold-glow);
  flex-shrink: 0;
}

.brand-text h1 {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  letter-spacing: 1.5px;
  color: var(--gold-light);
  text-shadow: 0 0 10px var(--gold-glow);
  line-height: 1.2;
}

.brand-text .subtitle {
  font-size: 0.78rem;
  color: var(--text-muted);
  letter-spacing: 0.8px;
  text-transform: uppercase;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.badge-stem {
  background: linear-gradient(135deg, rgba(212, 175, 55, 0.2), rgba(56, 189, 248, 0.2));
  border: 1px solid var(--gold-primary);
  color: var(--gold-light);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 1px;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.btn-icon {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  padding: 0.45rem 0.75rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  transition: var(--transition-smooth);
}

.btn-icon:hover {
  background: rgba(212, 175, 55, 0.15);
  border-color: var(--gold-primary);
  color: var(--gold-light);
  box-shadow: 0 0 12px var(--gold-glow);
}

/* Navigazione Tematica (Menu Orizzontale a Scorrimento / Schede) */
.topics-nav-bar {
  background: rgba(14, 19, 32, 0.85);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  padding: 0.6rem 1.5rem;
  overflow-x: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--gold-dark) transparent;
  display: flex;
  gap: 0.5rem;
  position: sticky;
  top: 61px;
  z-index: 90;
  backdrop-filter: blur(12px);
}

.topics-nav-bar::-webkit-scrollbar {
  height: 4px;
}
.topics-nav-bar::-webkit-scrollbar-thumb {
  background: var(--gold-dark);
  border-radius: 2px;
}

.nav-tab {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-secondary);
  padding: 0.5rem 1rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 500;
  white-space: nowrap;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition-smooth);
  font-family: var(--font-sans);
}

.nav-tab:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-primary);
  border-color: rgba(212, 175, 55, 0.3);
}

.nav-tab.active {
  background: linear-gradient(135deg, rgba(212, 175, 55, 0.25), rgba(56, 189, 248, 0.2));
  border-color: var(--gold-primary);
  color: var(--gold-light);
  box-shadow: 0 0 14px var(--gold-glow);
  font-weight: 600;
}

.nav-tab .tab-num {
  font-family: var(--font-serif);
  font-size: 0.75rem;
  opacity: 0.8;
}

/* Sezione Hero introduttiva */
.hero-section {
  padding: 3rem 2rem 2.2rem;
  text-align: center;
  max-width: 1100px;
  margin: 0 auto;
  position: relative;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  background: rgba(212, 175, 55, 0.1);
  border: 1px solid var(--border-subtle);
  padding: 0.4rem 1.2rem;
  border-radius: 999px;
  font-size: 0.82rem;
  color: var(--gold-light);
  margin-bottom: 1.2rem;
  letter-spacing: 1px;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  font-weight: 700;
  letter-spacing: 1.5px;
  line-height: 1.2;
  margin-bottom: 1.2rem;
  background: linear-gradient(135deg, #ffffff 20%, var(--gold-light) 60%, var(--gold-primary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: 0 0 30px rgba(212, 175, 55, 0.25);
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 840px;
  margin: 0 auto 1.5rem;
  line-height: 1.7;
}

.hero-quote {
  font-family: var(--font-poetic);
  font-size: 1.35rem;
  font-style: italic;
  color: var(--text-terzina);
  background: rgba(14, 19, 32, 0.7);
  border-left: 3px solid var(--gold-primary);
  border-right: 3px solid var(--gold-primary);
  padding: 1rem 2rem;
  margin: 0 auto 2rem;
  max-width: 780px;
  border-radius: var(--radius-sm);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-credits {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-credits a {
  color: var(--celestial-blue);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: var(--transition-smooth);
}

.hero-credits a:hover {
  color: var(--gold-light);
  text-decoration: underline;
}

/* Contenuto Principale / Moduli */
.main-content {
  flex: 1;
  max-width: 1340px;
  width: 100%;
  margin: 0 auto;
  padding: 1rem 2rem 4rem;
}

/* Schede Modulo */
.module-container {
  display: none;
  animation: fadeIn 0.4s ease-out forwards;
}

.module-container.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Struttura Modulo a 2 Colonne */
.module-layout {
  display: grid;
  grid-template-columns: 1fr 1.25fr;
  gap: 2rem;
  align-items: start;
}

@media (max-width: 1020px) {
  .module-layout {
    grid-template-columns: 1fr;
  }
}

/* Card Teoria & Versi */
.poetic-card {
  background: var(--bg-card);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.poetic-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--gold-primary), var(--celestial-blue), transparent);
}

.canto-tag {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 0.78rem;
  letter-spacing: 1.2px;
  color: var(--gold-light);
  text-transform: uppercase;
  background: rgba(212, 175, 55, 0.12);
  padding: 0.3rem 0.8rem;
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
  border: 1px solid rgba(212, 175, 55, 0.25);
}

.module-title {
  font-family: var(--font-serif);
  font-size: 1.7rem;
  color: var(--text-primary);
  margin-bottom: 1rem;
  line-height: 1.3;
}

.verses-box {
  background: rgba(7, 9, 14, 0.75);
  border-left: 3px solid var(--gold-primary);
  padding: 1.2rem 1.5rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 1.2rem 0;
  font-family: var(--font-poetic);
  font-size: 1.15rem;
  line-height: 1.75;
  color: var(--text-terzina);
  font-style: italic;
  box-shadow: inset 0 2px 8px rgba(0,0,0,0.5);
}

.verses-box .canto-ref {
  display: block;
  font-family: var(--font-sans);
  font-size: 0.75rem;
  color: var(--text-muted);
  font-style: normal;
  margin-top: 0.75rem;
  text-align: right;
}

.explanation-section {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.explanation-section p {
  margin-bottom: 1rem;
}

.explanation-section h4 {
  font-family: var(--font-serif);
  color: var(--gold-light);
  font-size: 1rem;
  margin: 1.4rem 0 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.odifreddi-insight {
  background: rgba(56, 189, 248, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin-top: 1.5rem;
  font-size: 0.88rem;
  line-height: 1.6;
}

.odifreddi-insight .insight-header {
  font-weight: 600;
  color: var(--celestial-blue);
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-bottom: 0.4rem;
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 1px;
}

/* Card Interattiva (Simulatore) */
.interactive-card {
  background: var(--bg-card);
  backdrop-filter: var(--glass-blur);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  box-shadow: var(--shadow-md);
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.interactive-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 0.85rem;
}

.interactive-title {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  color: var(--gold-light);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.interactive-hint {
  font-size: 0.78rem;
  color: var(--celestial-blue);
  background: rgba(56, 189, 248, 0.1);
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  border: 1px solid rgba(56, 189, 248, 0.2);
}

.canvas-container {
  position: relative;
  width: 100%;
  border-radius: var(--radius-sm);
  background: #05070b;
  border: 1px solid rgba(255, 255, 255, 0.08);
  overflow: hidden;
  box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 360px;
}

canvas {
  display: block;
  max-width: 100%;
  touch-action: none;
}

.controls-panel {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  background: rgba(7, 9, 14, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
}

.control-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
}

.control-row label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.control-value {
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: var(--gold-light);
  min-width: 4rem;
  text-align: right;
}

/* Sliders personalizzati */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 3px;
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--gold-light);
  box-shadow: 0 0 10px var(--gold-glow);
  cursor: pointer;
  transition: transform 0.1s;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

/* Pulsanti Azione */
.btn-primary {
  background: linear-gradient(135deg, var(--gold-primary), var(--gold-dark));
  color: #000;
  font-weight: 600;
  border: none;
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.9rem;
  letter-spacing: 0.5px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: var(--transition-smooth);
  box-shadow: 0 4px 14px rgba(212, 175, 55, 0.3);
}

.btn-primary:hover {
  filter: brightness(1.15);
  box-shadow: 0 6px 20px var(--gold-glow);
  transform: translateY(-1px);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-primary);
  font-weight: 500;
  border: 1px solid rgba(255, 255, 255, 0.15);
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.88rem;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  transition: var(--transition-smooth);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.14);
  border-color: rgba(255, 255, 255, 0.3);
}

/* Data metrics pill */
.data-display-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 0.75rem;
}

.metric-box {
  background: rgba(14, 19, 32, 0.8);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  text-align: center;
}

.metric-box .metric-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.8px;
  margin-bottom: 0.25rem;
}

.metric-box .metric-value {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--gold-light);
}

/* Footer Rinascimentale-STEM Avanzato */
.app-footer {
  border-top: 1px solid var(--border-subtle);
  background: radial-gradient(circle at 50% 0%, rgba(212, 175, 55, 0.06), transparent 70%),
              #07090e;
  padding: 3.5rem 2rem 2rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 2rem;
}

.footer-container {
  max-width: 1240px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.3fr 1.3fr 1fr;
  gap: 2.5rem;
}

@media (max-width: 900px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

.footer-col h4 {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  color: var(--gold-light);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  letter-spacing: 0.5px;
}

.footer-col p {
  color: var(--text-muted);
  line-height: 1.7;
  font-size: 0.88rem;
  margin-bottom: 1rem;
}

.footer-links-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.footer-links-list a, .footer-links-list button {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.85rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
  transition: var(--transition-smooth);
  font-family: inherit;
  text-align: left;
}

.footer-links-list a:hover, .footer-links-list button:hover {
  color: var(--gold-light);
  transform: translateX(3px);
}

.footer-source-card {
  background: rgba(14, 19, 32, 0.7);
  border: 1px solid rgba(212, 175, 55, 0.2);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin-bottom: 1rem;
  transition: var(--transition-smooth);
}

.footer-source-card:hover {
  border-color: var(--gold-primary);
  box-shadow: 0 4px 16px rgba(212, 175, 55, 0.15);
}

.footer-source-card h5 {
  font-family: var(--font-serif);
  color: var(--gold-light);
  font-size: 0.92rem;
  margin-bottom: 0.3rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.footer-source-card p {
  font-size: 0.82rem;
  margin-bottom: 0.6rem;
  line-height: 1.5;
}

.footer-source-actions {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.footer-bottom-bar {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 1.75rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  text-align: center;
}

.footer-triple-stars {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  font-family: var(--font-poetic);
  font-size: 1.05rem;
  color: var(--text-terzina);
  font-style: italic;
}

.footer-star-verse {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.footer-copy {
  font-size: 0.78rem;
  color: var(--text-muted);
}