/* ==========================================================================
   BOOSTBIKE - Apple MacPro Style Design System
   Hochschule Niederrhein | Prof. Dr.-Ing. Schettel & Prof. Dr.-Ing. Deutges
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Outfit:wght@400;600;700;900&display=swap');

:root {
  /* Color Palette - Deep Dark Mode */
  --bg-dark: #0a0a0c;
  --bg-surface: #121214;
  --bg-card: rgba(26, 26, 30, 0.65);
  --bg-card-hover: rgba(36, 36, 42, 0.8);
  --bg-glass: rgba(255, 255, 255, 0.04);
  --bg-glass-strong: rgba(255, 255, 255, 0.08);
  
  /* Accent Colors - Neon & Tech Glow */
  --accent-cyan: #00f2fe;
  --accent-blue: #4facfe;
  --accent-green: #00ff87;
  --accent-purple: #fc00ff;
  --accent-red: #ff3366;
  --accent-orange: #ff9900;
  
  /* Gradients */
  --grad-cyan-blue: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-blue) 100%);
  --grad-green-cyan: linear-gradient(135deg, var(--accent-green) 0%, var(--accent-cyan) 100%);
  --grad-purple-blue: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-blue) 100%);
  --grad-text: linear-gradient(180deg, #ffffff 0%, #a1a1a6 100%);
  --grad-text-glow: linear-gradient(90deg, #00f2fe 0%, #4facfe 50%, #00ff87 100%);
  
  /* Typography */
  --font-main: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  
  /* Text Colors */
  --text-main: #f5f5f7;
  --text-muted: #86868b;
  --text-dark: #1d1d1f;
  
  /* Borders & Shadows */
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-glass-hover: rgba(0, 242, 254, 0.4);
  --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 50px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 30px rgba(0, 242, 254, 0.25);
  
  /* Radii & Transitions */
  --radius-xl: 28px;
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 8px;
  --transition-smooth: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-fast: all 0.2s ease;
}

/* ==========================================================================
   Reset & Base Styles
   ========================================================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--bg-dark);
  color: var(--text-main);
}

body {
  font-family: var(--font-main);
  line-height: 1.6;
  overflow-x: hidden;
  background: radial-gradient(circle at 50% 0%, #1a1a24 0%, var(--bg-dark) 70%);
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition-fast);
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ==========================================================================
   Typography & Utility Classes
   ========================================================================== */
h1, h2, h3, h4, .font-display {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.text-gradient {
  background: var(--grad-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.text-gradient-cyan {
  background: var(--grad-cyan-blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.text-gradient-glow {
  background: var(--grad-text-glow);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.section-tag {
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--accent-cyan);
  margin-bottom: 0.75rem;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.section-tag::before {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 10px var(--accent-cyan);
}

.section-title {
  font-size: clamp(2.2rem, 4vw, 3.5rem);
  line-height: 1.1;
  margin-bottom: 1.25rem;
  color: var(--text-main);
}

.section-subtitle {
  font-size: clamp(1.1rem, 1.5vw, 1.35rem);
  color: var(--text-muted);
  max-width: 700px;
  margin: 0 auto 3.5rem auto;
  font-weight: 400;
}

.container {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 2rem;
}

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

/* ==========================================================================
   Navigation (Apple Glassmorphism Bar)
   ========================================================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(10, 10, 12, 0.75);
  backdrop-filter: blur(25px);
  -webkit-backdrop-filter: blur(25px);
  border-bottom: 1px solid var(--border-glass);
  transition: var(--transition-smooth);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.4rem;
  letter-spacing: -0.03em;
}

.logo-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: var(--grad-cyan-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #000;
  font-weight: 900;
  font-size: 1.1rem;
  box-shadow: 0 0 15px rgba(0, 242, 254, 0.4);
}

.nav-links {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  position: relative;
}

.nav-link:hover, .nav-link.active {
  color: var(--text-main);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -6px;
  left: 0;
  width: 0%;
  height: 2px;
  background: var(--grad-cyan-blue);
  transition: var(--transition-fast);
  border-radius: 2px;
}

.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}

.nav-btn {
  padding: 0.6rem 1.25rem;
  border-radius: 50px;
  background: var(--grad-cyan-blue);
  color: #000;
  font-weight: 600;
  font-size: 0.9rem;
  transition: var(--transition-smooth);
  box-shadow: 0 0 20px rgba(0, 242, 254, 0.3);
}

.nav-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(0, 242, 254, 0.6);
  color: #000;
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  padding: 130px 0 80px 0;
  overflow: hidden;
}

.hero-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.15) 0%, rgba(0, 0, 0, 0) 70%);
  top: 40%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: -1;
  pointer-events: none;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 4rem;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.4rem 1rem;
  border-radius: 50px;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-glass);
  font-size: 0.85rem;
  color: var(--accent-cyan);
  margin-bottom: 1.5rem;
  backdrop-filter: blur(10px);
}

.hero-title {
  font-size: clamp(3rem, 5vw, 4.8rem);
  line-height: 1.05;
  margin-bottom: 1.5rem;
  font-weight: 800;
}

.hero-desc {
  font-size: clamp(1.1rem, 1.4vw, 1.3rem);
  color: var(--text-muted);
  margin-bottom: 2.5rem;
  max-width: 580px;
}

.hero-actions {
  display: flex;
  gap: 1.25rem;
  flex-wrap: wrap;
  margin-bottom: 3.5rem;
}

.btn-primary {
  padding: 1rem 2rem;
  border-radius: 50px;
  background: var(--grad-cyan-blue);
  color: #000;
  font-weight: 700;
  font-size: 1rem;
  transition: var(--transition-smooth);
  box-shadow: 0 10px 30px rgba(0, 242, 254, 0.3);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.btn-primary:hover {
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 15px 40px rgba(0, 242, 254, 0.5);
  color: #000;
}

.btn-secondary {
  padding: 1rem 2rem;
  border-radius: 50px;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-glass);
  color: var(--text-main);
  font-weight: 600;
  font-size: 1rem;
  transition: var(--transition-smooth);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.3);
  transform: translateY(-3px);
}

.hero-meta {
  display: flex;
  align-items: center;
  gap: 2rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-glass);
}

.meta-item {
  display: flex;
  flex-direction: column;
}

.meta-value {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-main);
}

.meta-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-visual {
  position: relative;
}

.image-card {
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  border: 1px solid var(--border-glass);
  background: var(--bg-card);
  box-shadow: var(--shadow-lg);
}

.image-card img {
  width: 100%;
  height: auto;
  transition: transform 0.7s ease;
}

.image-card:hover img {
  transform: scale(1.03);
}

.floating-badge {
  position: absolute;
  padding: 0.8rem 1.25rem;
  border-radius: var(--radius-md);
  background: rgba(18, 18, 20, 0.85);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(0, 242, 254, 0.3);
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  z-index: 10;
  animation: float 4s ease-in-out infinite;
}

.fb-1 {
  bottom: 30px;
  left: -20px;
  animation-delay: 0s;
}

.fb-2 {
  top: 40px;
  right: -20px;
  animation-delay: 2s;
  border-color: rgba(0, 255, 135, 0.3);
}

.fb-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(0, 242, 254, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  font-size: 1.25rem;
}

.fb-2 .fb-icon {
  background: rgba(0, 255, 135, 0.15);
  color: var(--accent-green);
}

.fb-text {
  display: flex;
  flex-direction: column;
}

.fb-title {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text-main);
}

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

@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-10px); }
}

/* ==========================================================================
   Project Intro & Professors Section
   ========================================================================== */
.section-padding {
  padding: 100px 0;
  position: relative;
}

.intro-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.glass-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  transition: var(--transition-smooth);
}

.glass-card:hover {
  border-color: var(--border-glass-hover);
  transform: translateY(-5px);
  box-shadow: var(--shadow-glow);
}

.prof-card {
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  padding: 1.5rem;
  background: var(--bg-glass);
  border-radius: var(--radius-md);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

.prof-avatar {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--grad-cyan-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1.4rem;
  color: #000;
  flex-shrink: 0;
}

.prof-info h3 {
  font-size: 1.25rem;
  color: var(--text-main);
  margin-bottom: 0.25rem;
}

.prof-info p {
  font-size: 0.9rem;
  color: var(--accent-cyan);
  font-weight: 500;
  margin-bottom: 0.5rem;
}

.prof-info span {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Basics & Safety Section (Fahrrad & Sicherheit)
   ========================================================================== */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 2rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  transition: var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--grad-cyan-blue);
  opacity: 0;
  transition: var(--transition-smooth);
}

.feature-card:hover {
  transform: translateY(-8px);
  border-color: rgba(0, 242, 254, 0.3);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.5);
}

.feature-card:hover::before {
  opacity: 1;
}

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  background: rgba(0, 242, 254, 0.1);
  border: 1px solid rgba(0, 242, 254, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--accent-cyan);
  margin-bottom: 1.5rem;
  transition: var(--transition-smooth);
}

.feature-card:hover .feature-icon {
  background: var(--grad-cyan-blue);
  color: #000;
  transform: scale(1.1) rotate(5deg);
}

.feature-card h3 {
  font-size: 1.35rem;
  margin-bottom: 1rem;
  color: var(--text-main);
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

.formula-box {
  background: rgba(0, 0, 0, 0.5);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  font-family: monospace;
  color: var(--accent-cyan);
  font-size: 0.9rem;
  margin-top: auto;
}

/* ==========================================================================
   Integrated Engineering Details Box (in Storage Tabs)
   ========================================================================== */
.tech-details-box {
  background: rgba(10, 15, 20, 0.6);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin-bottom: 2rem;
  border-left: 3px solid var(--accent-cyan);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.tech-details-box h4 {
  font-size: 1.05rem;
  color: var(--text-main);
  margin-bottom: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.tech-details-box ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.tech-details-box li {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.5;
  position: relative;
  padding-left: 1.5rem;
}

.tech-details-box li::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--accent-cyan);
  font-weight: bold;
}

/* Efficiency Chain Box (in Storage Tabs) */
.eff-chain-box {
  background: rgba(0, 0, 0, 0.55);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  margin-top: 1.5rem;
  margin-bottom: 2rem;
  box-shadow: inset 0 0 25px rgba(0, 0, 0, 0.7);
  border-right: 3px solid var(--accent-green);
}

.eff-chain-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  flex-wrap: wrap;
  gap: 0.5rem;
}

.eff-title {
  font-size: 0.9rem;
  color: var(--text-main);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.eff-total {
  font-size: 1.15rem;
  color: var(--accent-green);
  font-family: var(--font-display);
}

.eff-total strong {
  font-weight: 800;
  text-shadow: 0 0 10px rgba(0, 255, 135, 0.4);
}

.eff-steps {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.eff-step {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 8px;
  padding: 0.6rem 0.75rem;
  text-align: center;
  flex: 1;
  min-width: 100px;
  transition: var(--transition-smooth);
}

.eff-step:hover {
  background: rgba(0, 242, 254, 0.1);
  border-color: rgba(0, 242, 254, 0.3);
  transform: translateY(-2px);
}

.step-name {
  display: block;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 0.3rem;
  line-height: 1.2;
}

.step-val {
  display: block;
  font-size: 1rem;
  color: var(--accent-cyan);
  font-family: var(--font-display);
  font-weight: 700;
}

.eff-arrow {
  color: var(--text-muted);
  font-size: 1rem;
  font-weight: bold;
}



/* ==========================================================================
   The 3 Storage Types (Die 3 Bauweisen - Interaktiver Tab Switcher)
   ========================================================================== */
.tabs-header {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 3.5rem;
  flex-wrap: wrap;
}

.tab-btn {
  padding: 1rem 2.25rem;
  border-radius: 50px;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  color: var(--text-muted);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  cursor: pointer;
  transition: var(--transition-smooth);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.tab-btn:hover {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-main);
}

.tab-btn.active {
  background: var(--grad-cyan-blue);
  color: #000;
  border-color: transparent;
  box-shadow: 0 0 25px rgba(0, 242, 254, 0.4);
}

.tab-content {
  display: none;
  animation: fadeIn 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ==========================================================================
   New Prototype Layout & Interactive Efficiency Sliders
   ========================================================================== */
.prototype-layout {
  display: flex;
  flex-direction: column;
  gap: 3.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-xl);
  padding: 3rem;
  box-shadow: var(--shadow-lg);
}

/* 1. Row: Visual Pair Grid (Side by Side Images) */
.visual-pair-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

.visual-box {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: inset 0 0 20px rgba(0,0,0,0.6);
}

.visual-header {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.visual-box .img-wrapper {
  position: relative;
  width: 100%;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-glass);
  background: #000;
  aspect-ratio: 16 / 10;
  display: flex;
  align-items: center;
  justify-content: center;
}

.visual-box .img-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #0d0d0f;
  transition: transform 0.4s ease;
}

.visual-box .img-wrapper:hover img {
  transform: scale(1.04);
}

/* 2. Row: Content Pair Grid (Description left, Calculator right) */
.content-pair-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 3.5rem;
  align-items: start;
}

.desc-column {
  display: flex;
  flex-direction: column;
}

.desc-column h3 {
  font-size: 2.2rem;
  margin-bottom: 1rem;
  color: var(--text-main);
}

.desc-column .generation-tag {
  display: inline-block;
  padding: 0.35rem 0.85rem;
  border-radius: 6px;
  background: rgba(0, 242, 254, 0.15);
  color: var(--accent-cyan);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
  width: fit-content;
}

.desc-column p {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin-bottom: 2rem;
  line-height: 1.7;
}

/* Interactive Efficiency Box */
.calc-column {
  position: sticky;
  top: 100px;
}

.eff-interactive-box {
  background: rgba(13, 13, 18, 0.85);
  border: 1px solid rgba(0, 242, 254, 0.3);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.6), inset 0 0 30px rgba(0, 242, 254, 0.05);
  backdrop-filter: blur(20px);
}

.eff-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  gap: 1rem;
}

.eff-title {
  display: block;
  font-size: 1.15rem;
  color: var(--text-main);
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.eff-sub {
  display: block;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.btn-reset {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: var(--text-main);
  padding: 0.4rem 0.8rem;
  border-radius: 6px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.btn-reset:hover {
  background: var(--accent-cyan);
  color: #000;
  border-color: var(--accent-cyan);
  transform: rotate(-15deg);
}

.eff-total-display {
  background: rgba(0, 242, 254, 0.1);
  border: 1px solid var(--accent-cyan);
  border-radius: var(--radius-md);
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  box-shadow: 0 0 20px rgba(0, 242, 254, 0.15);
}

.eff-total-display .label {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
}

.eff-total-display .val {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent-green);
  text-shadow: 0 0 15px rgba(0, 255, 135, 0.5);
}

.slider-chain {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.eff-slider-item {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 8px;
  padding: 0.85rem 1rem;
  transition: border-color 0.2s ease;
}

.eff-slider-item:hover {
  border-color: rgba(0, 242, 254, 0.3);
}

.slider-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.slider-info strong {
  font-family: var(--font-display);
  font-size: 1rem;
  color: var(--accent-cyan);
}

.eff-slider {
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: rgba(255, 255, 255, 0.1);
  outline: none;
  -webkit-appearance: none;
  cursor: pointer;
}

.eff-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 10px var(--accent-cyan);
  cursor: pointer;
  transition: transform 0.1s ease;
}

.eff-slider::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

.chain-arrow {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 1px;
}

.eff-formula-note {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
  border-top: 1px dashed rgba(255, 255, 255, 0.1);
  padding-top: 1rem;
}

/* 3. Row: Pros & Cons Full Width */
.pros-cons.full-width {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  border-top: 1px solid var(--border-glass);
  padding-top: 2.5rem;
}

/* Responsive adjustments for new prototype layout */
@media (max-width: 992px) {
  .visual-pair-grid,
  .content-pair-grid,
  .pros-cons.full-width {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .calc-column {
    position: static;
  }
}

/* Keep legacy grid name for other sections if needed */
.storage-grid {
  display: block;
}

.storage-info h3 {
  font-size: 2.2rem;
  margin-bottom: 1rem;
  color: var(--text-main);
}

.storage-info .generation-tag {
  display: inline-block;
  padding: 0.35rem 0.85rem;
  border-radius: 6px;
  background: rgba(0, 242, 254, 0.15);
  color: var(--accent-cyan);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  margin-bottom: 1.5rem;
}

.storage-info p {
  color: var(--text-muted);
  font-size: 1.05rem;
  margin-bottom: 2rem;
}

.specs-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 2rem;
}

.spec-item {
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.spec-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  text-transform: uppercase;
  margin-bottom: 0.35rem;
}

.spec-val {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.pros-cons {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

.pc-box h4 {
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.pc-box.pro h4 { color: var(--accent-green); }
.pc-box.con h4 { color: var(--accent-red); }

.pc-box ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.pc-box li {
  font-size: 0.85rem;
  color: var(--text-muted);
  position: relative;
  padding-left: 1.25rem;
}

.pc-box.pro li::before {
  content: '+';
  position: absolute;
  left: 0;
  color: var(--accent-green);
  font-weight: 700;
}

.pc-box.con li::before {
  content: '−';
  position: absolute;
  left: 0;
  color: var(--accent-red);
  font-weight: 700;
}

/* ==========================================================================
   Comparison Table & Interactive Calculator
   ========================================================================== */
.table-responsive {
  overflow-x: auto;
  margin-bottom: 5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-glass);
  background: var(--bg-card);
  box-shadow: var(--shadow-lg);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.comparison-table th, .comparison-table td {
  padding: 1.5rem 2rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.comparison-table th {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-main);
  background: rgba(0, 0, 0, 0.3);
}

.comparison-table td {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.comparison-table tr:hover td {
  background: rgba(255, 255, 255, 0.03);
  color: var(--text-main);
}

.comparison-table td:first-child {
  font-weight: 600;
  color: var(--text-main);
}

.highlight-col {
  background: rgba(0, 242, 254, 0.05);
  color: var(--accent-cyan) !important;
  font-weight: 600 !important;
}

/* Interactive Calculator */
.calc-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-xl);
  padding: 3rem;
  max-width: 900px;
  margin: 0 auto;
  box-shadow: var(--shadow-lg);
}

.calc-header {
  text-align: center;
  margin-bottom: 2.5rem;
}

.calc-header h3 {
  font-size: 1.8rem;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.calc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

/* ==========================================================================
   Apple Style Stepped Principle Selector & HUD Display (Ampel-Boost Rechner)
   ========================================================================== */
.principle-selector-group {
  background: rgba(0, 0, 0, 0.55);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  box-shadow: inset 0 0 25px rgba(0,0,0,0.6);
}

.principle-selector-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-cyan);
  margin-bottom: 1rem;
}

.stepped-slider-container {
  position: relative;
  margin: 1rem 0 0.5rem 0;
}

.apple-stepped-slider {
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.15);
  outline: none;
  -webkit-appearance: none;
  cursor: pointer;
  box-shadow: inset 0 0 5px rgba(0,0,0,0.8);
}

.apple-stepped-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-cyan);
  box-shadow: 0 0 15px var(--accent-cyan), 0 0 5px #fff;
  cursor: pointer;
  transition: transform 0.15s cubic-bezier(0.16, 1, 0.3, 1), background-color 0.3s ease;
}

.apple-stepped-slider::-webkit-slider-thumb:hover {
  transform: scale(1.25);
}

.principle-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 1rem;
  gap: 0.5rem;
}

.principle-label-item {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: center;
  flex: 1;
  padding: 0.6rem 0.4rem;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.05);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
}

.principle-label-item .p-icon {
  font-size: 1.2rem;
  margin-bottom: 0.1rem;
}

.principle-label-item small {
  font-size: 0.7rem;
  font-weight: 400;
  color: var(--text-secondary);
}

.principle-label-item:hover {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-2px);
}

.principle-label-item.active {
  color: #000;
  background: var(--accent-cyan);
  border-color: var(--accent-cyan);
  font-weight: 700;
  box-shadow: 0 0 20px rgba(0, 242, 254, 0.4);
  transform: translateY(-3px);
}

.principle-label-item.active small {
  color: rgba(0, 0, 0, 0.7);
  font-weight: 600;
}

/* Systemwirkungsgrad Anzeigefeld (von oben) */
.eff-hud-display {
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid var(--accent-cyan);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  box-shadow: 0 0 25px rgba(0, 242, 254, 0.15), inset 0 0 15px rgba(0, 242, 254, 0.05);
  transition: all 0.3s ease;
}

.eff-hud-display .hud-label {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.eff-hud-display .hud-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

.eff-hud-display .hud-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.eff-hud-display .hud-value {
  font-family: var(--font-display);
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--accent-green);
  text-shadow: 0 0 20px rgba(0, 255, 135, 0.6);
  transition: color 0.3s ease, text-shadow 0.3s ease;
}

.slider-group {
  margin-bottom: 2rem;
}

.slider-label {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.75rem;
  font-weight: 500;
  color: var(--text-main);
}

.slider-val {
  color: var(--accent-cyan);
  font-weight: 700;
  font-family: var(--font-display);
}

input[type=range] {
  width: 100%;
  -webkit-appearance: none;
  background: rgba(255, 255, 255, 0.1);
  height: 8px;
  border-radius: 4px;
  outline: none;
}

input[type=range]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-cyan);
  cursor: pointer;
  box-shadow: 0 0 15px var(--accent-cyan);
  transition: transform 0.2s ease;
}

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

.calc-results {
  background: rgba(0, 0, 0, 0.6);
  border: 1px solid rgba(0, 242, 254, 0.2);
  border-radius: var(--radius-lg);
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.res-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 1rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.res-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.res-label {
  font-size: 0.95rem;
  color: var(--text-muted);
}

.res-value {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--accent-green);
}

/* ==========================================================================
   Credits & Team Section (Die Köpfe hinter dem BoostBike)
   ========================================================================== */
.credits-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  margin-top: 3rem;
}

@media (max-width: 900px) {
  .credits-grid {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   3 Blöcke nebeneinander (Studentische Prototypen Teams)
   ========================================================================== */
.student-blocks-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 2rem;
}

@media (max-width: 1024px) {
  .student-blocks-grid {
    grid-template-columns: 1fr;
  }
}

.student-principle-card {
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
}

.principle-card-header {
  min-height: 180px;
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
}

@media (max-width: 1024px) {
  .principle-card-header {
    min-height: auto;
  }
}

.team-subgroup {
  margin-top: 1.25rem;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-md);
  padding: 1.25rem;
}

.team-subgroup + .team-subgroup {
  margin-top: 1rem;
}

.team-sub-title {
  font-size: 0.92rem;
  color: var(--text-main);
  font-weight: 700;
  margin-bottom: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  padding-bottom: 0.5rem;
}

.student-list.single-col {
  grid-template-columns: 1fr;
}

.credit-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.4);
  transition: var(--transition-smooth);
}

.credit-card:hover {
  border-color: rgba(0, 242, 254, 0.4);
  transform: translateY(-5px);
  box-shadow: 0 15px 40px rgba(0, 242, 254, 0.1);
}

.leadership-card {
  grid-column: span 2;
  background: linear-gradient(135deg, rgba(20, 25, 35, 0.8) 0%, rgba(10, 15, 20, 0.9) 100%);
  border-color: rgba(0, 255, 135, 0.3);
}

@media (max-width: 900px) {
  .leadership-card {
    grid-column: span 1;
  }
}

.credit-badge {
  display: inline-block;
  background: rgba(0, 242, 254, 0.1);
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 242, 254, 0.3);
  padding: 0.35rem 0.85rem;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
}

.leadership-card .credit-badge {
  background: rgba(0, 255, 135, 0.1);
  color: var(--accent-green);
  border-color: rgba(0, 255, 135, 0.3);
}

.credit-card h3 {
  font-size: 1.5rem;
  color: var(--text-main);
  margin-bottom: 0.75rem;
}

.credit-desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 1.75rem;
}

.prof-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

@media (max-width: 700px) {
  .prof-list {
    grid-template-columns: 1fr;
  }
}

.prof-item {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
}

.prof-item strong {
  display: block;
  font-size: 1.05rem;
  color: var(--text-main);
  margin-bottom: 0.2rem;
}

.prof-item span {
  display: block;
  font-size: 0.85rem;
  color: var(--accent-cyan);
}

.student-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem 1rem;
}

@media (max-width: 500px) {
  .student-list {
    grid-template-columns: 1fr;
  }
}

.student-list li {
  color: var(--text-main);
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.student-list li::before {
  content: "✦";
  color: var(--accent-cyan);
  font-size: 0.8rem;
}

.student-list li.team-extra {
  color: var(--text-muted);
  font-style: italic;
  grid-column: span 2;
  margin-top: 0.5rem;
}

@media (max-width: 500px) {
  .student-list li.team-extra {
    grid-column: span 1;
  }
}

/* ==========================================================================
   Footer
   ========================================================================== */
.footer {
  background: #050507;
  border-top: 1px solid var(--border-glass);
  padding: 80px 0 40px 0;
  margin-top: 50px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 4rem;
  margin-bottom: 4rem;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-top: 1rem;
  max-width: 320px;
}

.footer-col h4 {
  font-size: 1rem;
  color: var(--text-main);
  margin-bottom: 1.5rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-col a {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-col a:hover {
  color: var(--accent-cyan);
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-grid, .intro-grid, .storage-grid, .calc-grid {
    grid-template-columns: 1fr;
    gap: 3rem;
  }
  
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
  }
  
  .fb-1, .fb-2 {
    position: relative;
    top: auto;
    left: auto;
    right: auto;
    bottom: auto;
    margin-top: 1rem;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none; /* Can be expanded to hamburger menu */
  }
  
  .section-padding {
    padding: 70px 0;
  }
  
  .grid-2, .grid-3, .specs-grid, .pros-cons {
    grid-template-columns: 1fr;
  }
  
  .storage-grid {
    padding: 1.5rem;
  }
  
  .calc-card {
    padding: 1.5rem;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: 1rem;
    text-align: center;
  }
}