/* ============================================
   E-Scooter - Electric Velocity Design
   ダークモード × ネオングリーン
   ============================================ */

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

:root {
  /* Color Palette - Electric Velocity */
  --primary: #00E676;
  --primary-dark: #00C853;
  --primary-light: #69F0AE;
  --accent: #00B0FF;
  --accent-light: #40C4FF;
  --accent-dark: #0091EA;
  
  /* Dark Theme */
  --bg-dark: #0D1117;
  --bg-card: #161B22;
  --bg-elevated: #21262D;
  --bg-hover: #30363D;
  
  /* Text Colors */
  --text-primary: #F0F6FC;
  --text-secondary: #8B949E;
  --text-muted: #6E7681;
  
  /* Borders & Effects */
  --border-default: #30363D;
  --border-muted: #21262D;
  --glow-primary: 0 0 20px rgba(0, 230, 118, 0.3);
  --glow-accent: 0 0 20px rgba(0, 176, 255, 0.3);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);
  
  /* Typography */
  --font-display: 'Outfit', 'Noto Sans JP', sans-serif;
  --font-body: 'Noto Sans JP', 'Hiragino Sans', sans-serif;
  
  /* Spacing */
  --section-padding: 80px;
  --container-max: 1200px;
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  
  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-full: 9999px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-primary);
  background-color: var(--bg-dark);
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  color: var(--primary-light);
}

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

.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================
   Header
   ============================================ */

header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(13, 17, 23, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-default);
}

header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 72px;
}

.logo a {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Desktop Navigation */
nav ul {
  list-style: none;
  display: flex;
  gap: 8px;
}

nav a {
  display: block;
  padding: 10px 16px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
}

nav a:hover,
nav a.active {
  background: var(--primary);
  color: var(--bg-dark);
}

/* Mobile Menu Button */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

.menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  position: relative;
  min-height: 650px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 72px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: none;
}

.hero-bg::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    135deg,
    rgba(13, 17, 23, 0.85) 0%,
    rgba(0, 230, 118, 0.2) 50%,
    rgba(0, 176, 255, 0.3) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 60px 24px;
  max-width: 900px;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  color: #ffffff;
  line-height: 1.2;
  margin-bottom: 24px;
  text-shadow: 
    2px 2px 0 #000,
    -2px 2px 0 #000,
    2px -2px 0 #000,
    -2px -2px 0 #000,
    0 4px 8px rgba(0, 0, 0, 0.5);
}

.hero h1 span {
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.2rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 36px;
  background: var(--primary);
  color: var(--bg-dark);
  font-weight: 700;
  font-size: 1.1rem;
  border-radius: var(--radius-full);
  box-shadow: var(--glow-primary);
  transition: all var(--transition-base);
}

.hero-cta:hover {
  background: var(--primary-light);
  color: var(--bg-dark);
  transform: translateY(-2px);
  box-shadow: 0 0 30px rgba(0, 230, 118, 0.5);
}

/* ============================================
   Stats Section
   ============================================ */

.stats {
  padding: 60px 0;
  background: var(--bg-card);
  border-top: 1px solid var(--border-default);
  border-bottom: 1px solid var(--border-default);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}

.stat-item {
  text-align: center;
  padding: 24px;
}

.stat-number {
  font-family: var(--font-display);
  font-size: 2.8rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 8px;
}

.stat-label {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* ============================================
   Introduction Section
   ============================================ */

.introduction {
  padding: var(--section-padding) 0;
}

.introduction h2 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 24px;
  text-align: center;
}

.introduction h2::after {
  content: '';
  display: block;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  margin: 16px auto 0;
  border-radius: 2px;
}

.introduction p {
  max-width: 900px;
  margin: 0 auto;
  font-size: 1.05rem;
  line-height: 2;
  color: var(--text-secondary);
}

/* ============================================
   Features Section
   ============================================ */

.features {
  padding: var(--section-padding) 0;
  background: var(--bg-card);
}

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-header h2 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.section-header p {
  font-size: 1.1rem;
  color: var(--text-muted);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
  transition: all var(--transition-base);
}

.feature-card:hover {
  transform: translateY(-8px);
  border-color: var(--primary);
  box-shadow: var(--glow-primary);
}

.feature-icon {
  width: 72px;
  height: 72px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
  font-size: 2rem;
}

.feature-card h3 {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.feature-card p {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
}

.feature-card .learn-more {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 20px;
  font-weight: 600;
  color: var(--primary);
}

.feature-card .learn-more:hover {
  color: var(--primary-light);
}

/* ============================================
   News Section
   ============================================ */

.news {
  padding: var(--section-padding) 0;
}

.news h2 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 32px;
  text-align: center;
}

.news-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 900px;
  margin: 0 auto;
}

.news-item {
  background: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  padding: 24px;
  display: flex;
  align-items: flex-start;
  gap: 20px;
  transition: all var(--transition-base);
}

.news-item:hover {
  border-color: var(--primary);
  transform: translateX(4px);
}

.news-item .date {
  flex-shrink: 0;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--primary);
  background: rgba(0, 230, 118, 0.1);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
}

.news-item p {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

.news-item p strong {
  color: var(--text-primary);
}

.news-more {
  text-align: center;
  margin-top: 32px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  background: var(--primary);
  color: var(--bg-dark);
  font-weight: 700;
  border-radius: var(--radius-full);
  transition: all var(--transition-base);
}

.btn-primary:hover {
  background: var(--primary-light);
  color: var(--bg-dark);
  transform: translateY(-2px);
  box-shadow: var(--glow-primary);
}

/* ============================================
   Topics Grid
   ============================================ */

.topics {
  padding: var(--section-padding) 0;
  background: var(--bg-card);
}

.topics h2 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 40px;
  text-align: center;
}

.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.topic-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
}

.topic-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent);
  box-shadow: var(--glow-accent);
}

.topic-card-content {
  padding: 24px;
}

.topic-card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.topic-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.topic-card .read-more {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-top: 16px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent);
}

/* ============================================
   Footer
   ============================================ */

footer {
  background: var(--bg-elevated);
  border-top: 1px solid var(--border-default);
  padding: 60px 0 32px;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand h3 {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--text-muted);
}

.footer-links h4 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.footer-links ul {
  list-style: none;
}

.footer-links li {
  margin-bottom: 12px;
}

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

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

.footer-bottom {
  border-top: 1px solid var(--border-default);
  padding-top: 24px;
  text-align: center;
}

.footer-bottom p {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ============================================
   Sub Pages
   ============================================ */

.page-hero {
  background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-elevated) 100%);
  padding: 120px 0 60px;
  text-align: center;
  margin-top: 72px;
  border-bottom: 1px solid var(--border-default);
}

.page-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.page-hero p {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 600px;
  margin: 0 auto;
}

.page-content {
  padding: 60px 0;
}

.page-content h2 {
  font-family: var(--font-display);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 48px 0 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--primary);
}

.page-content h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 32px 0 16px;
}

.page-content p {
  margin-bottom: 20px;
  line-height: 1.9;
  color: var(--text-secondary);
}

.page-content ul,
.page-content ol {
  margin: 20px 0;
  padding-left: 24px;
  color: var(--text-secondary);
}

.page-content li {
  margin-bottom: 12px;
  line-height: 1.7;
}

/* Info Boxes */
.info-box {
  background: rgba(0, 230, 118, 0.1);
  border-left: 4px solid var(--primary);
  padding: 24px;
  margin: 24px 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.warning-box {
  background: rgba(0, 176, 255, 0.1);
  border-left: 4px solid var(--accent);
  padding: 24px;
  margin: 24px 0;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* ============================================
   Responsive Design
   ============================================ */

@media (max-width: 1024px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --section-padding: 60px;
  }
  
  header .container {
    height: 64px;
  }
  
  .logo a {
    font-size: 1.3rem;
  }
  
  /* Mobile Navigation */
  .menu-toggle {
    display: flex;
  }
  
  nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg-card);
    padding: 24px;
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    border-bottom: 1px solid var(--border-default);
  }
  
  nav.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }
  
  nav ul {
    flex-direction: column;
    gap: 8px;
  }
  
  nav a {
    display: block;
    padding: 14px 20px;
    text-align: center;
  }
  
  /* Hero Mobile */
  .hero {
    min-height: 500px;
    margin-top: 64px;
  }
  
  .hero h1 {
    font-size: 1.8rem;
  }
  
  .hero p {
    font-size: 1rem;
  }
  
  /* Stats Mobile */
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
  }
  
  .stat-number {
    font-size: 2rem;
  }
  
  /* Features Mobile */
  .features-grid {
    grid-template-columns: 1fr;
  }
  
  /* News Mobile */
  .news-item {
    flex-direction: column;
    gap: 12px;
  }
  
  /* Footer Mobile */
  .footer-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  
  /* Page Hero Mobile */
  .page-hero {
    padding: 100px 0 48px;
    margin-top: 64px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  
  .hero-content {
    padding: 40px 16px;
  }
  
  .hero-cta {
    padding: 14px 28px;
    font-size: 1rem;
  }
  
  .feature-card {
    padding: 24px;
  }
  
  .topics-grid {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   Animations
   ============================================ */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes glow {
  0%, 100% {
    box-shadow: var(--glow-primary);
  }
  50% {
    box-shadow: 0 0 30px rgba(0, 230, 118, 0.5);
  }
}

.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
}

.animate-on-scroll.visible {
  animation: fadeInUp 0.6s ease forwards;
}