:root {
  /* NeoAI.jp inspired Color Palette */
  --primary-dark: #0a0a0a;
  --secondary-dark: #1a1a1a;
  --accent-cyan: #00d4ff;
  --accent-purple: #8b5cf6;
  --accent-pink: #ec4899;
  --text-primary: #ffffff;
  --text-light: #ffffff;
  --primary-bg: #0f1923;
  --text-secondary: #a0a0a0;
  --text-muted: #666666;
  --slate-gray: #7a8b9a;
  --text-dark: #1e2d3d;
  --border-subtle: rgba(255, 255, 255, 0.1);
  --border-glow: rgba(0, 212, 255, 0.3);
  --bg-glass: rgba(26, 26, 26, 0.8);
  --bg-card: rgba(30, 30, 30, 0.9);
  --bg-hover: rgba(40, 40, 40, 0.9);

  /* Gradients - NeoAI.jp inspired */
  --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #8b5cf6 50%, #ec4899 100%);
  --gradient-dark: linear-gradient(135deg, #0a0a0a 0%, #1a1a1a 100%);
  --gradient-glass: linear-gradient(135deg, rgba(26, 26, 26, 0.8) 0%, rgba(40, 40, 40, 0.6) 100%);
  --gradient-card: linear-gradient(135deg, rgba(30, 30, 30, 0.9) 0%, rgba(40, 40, 40, 0.8) 100%);
  --gradient-text: linear-gradient(135deg, #00d4ff 0%, #8b5cf6 100%);
  --gradient-border: linear-gradient(135deg, #00d4ff 0%, #ec4899 100%);
  --gradient-hero: linear-gradient(135deg, #0f1923 0%, #1a2a3a 50%, #0d1b2a 100%);
  --gradient-cta: linear-gradient(135deg, #64b4ff 0%, #3a7ec4 100%);

  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-secondary: 'Noto Sans JP', sans-serif;
  --font-mono: 'Fira Code', 'Courier New', monospace;

  /* Shadows */
  --shadow-glow: 0 0 20px rgba(0, 212, 255, 0.3);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 12px 48px rgba(0, 212, 255, 0.2);

  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
}

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

body {
  font-family: var(--font-primary);
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--gradient-dark);
  overflow-x: hidden;
  font-feature-settings: 'palt' 1;
  letter-spacing: -0.02em;
}

/* Typography - NeoAI.jp inspired */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-primary);
  font-weight: 600;
  line-height: 1.2;
  letter-spacing: -0.03em;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h1 { 
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 700;
}

h2 { 
  font-size: clamp(1.8rem, 4vw, 2.5rem);
}

h3 { 
  font-size: clamp(1.2rem, 3vw, 1.5rem);
}

p { 
  font-size: clamp(0.95rem, 1.5vw, 1.05rem);
  color: var(--text-secondary);
  line-height: 1.7;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

a:hover {
  color: var(--accent-purple);
  text-shadow: 0 0 10px rgba(139, 92, 246, 0.5);
}

/* Header - NeoAI.jp inspired */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 1rem 2rem;
  background: rgba(10, 10, 10, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

header.scrolled {
  background: rgba(10, 10, 10, 0.95);
  box-shadow: 0 4px 40px rgba(0, 0, 0, 0.5);
  border-bottom: 1px solid var(--border-glow);
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
}

.logo {
  font-size: 1.8rem;
  font-weight: 700;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

.nav-links a {
  color: var(--text-secondary);
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-md);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.nav-links a::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: var(--gradient-glass);
  transition: left 0.3s ease;
  z-index: -1;
}

.nav-links a:hover::before {
  left: 0;
}

.nav-links a:hover {
  color: var(--accent-cyan);
  text-shadow: var(--shadow-glow);
}

/* Hero Section - NeoAI.jp inspired */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: var(--gradient-dark);
  border-bottom: 1px solid var(--border-subtle);
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 20% 80%, rgba(0, 212, 255, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 20%, rgba(139, 92, 246, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 40% 40%, rgba(236, 72, 153, 0.05) 0%, transparent 50%);
  pointer-events: none;
}

#hero-canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  opacity: 0.6;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 2rem;
  max-width: 900px;
}

.hero h1 {
  font-size: clamp(3rem, 6vw, 5rem);
  font-weight: 700;
  margin-bottom: 1.5rem;
  line-height: 1.1;
}

.hero p {
  font-size: clamp(1.1rem, 2.5vw, 1.3rem);
  margin-bottom: 3rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.cta-button {
  display: inline-block;
  background: var(--gradient-primary);
  color: var(--text-primary);
  padding: 1rem 2.5rem;
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 1.1rem;
  box-shadow: var(--shadow-card);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  border: none;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.cta-button::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s ease;
}

.cta-button:hover::before {
  left: 100%;
}

.cta-button:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

/* Main Content - NeoAI.jp inspired */
main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 6rem 2rem;
}

.section {
  margin-bottom: 8rem;
}

.section-title {
  text-align: center;
  margin-bottom: 4rem;
}

.section-title h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  margin-bottom: 1rem;
  position: relative;
}

.section-title h2::after {
  content: '';
  position: absolute;
  bottom: -0.5rem;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: var(--gradient-border);
  border-radius: 2px;
}

.section-title p {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* Article Cards - NeoAI.jp inspired */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.article-card {
  background: var(--gradient-card);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.article-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gradient-glass);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

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

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

.article-card h3 {
  color: var(--text-primary);
  margin-bottom: 1rem;
  font-size: 1.4rem;
  font-weight: 600;
}

.article-card p {
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.article-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.9rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-subtle);
  padding-top: 1rem;
  margin-top: auto;
}

.category-tag {
  background: rgba(0, 212, 255, 0.1);
  color: var(--accent-cyan);
  padding: 0.4rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid rgba(0, 212, 255, 0.2);
}

/* About Section */
.about-content {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 4rem;
  align-items: center;
  margin-top: 3rem;
}

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

.profile-avatar {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: var(--gradient-cta);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1rem;
  font-size: 3rem;
  color: var(--text-light);
}

.profile-info h3 {
  color: var(--primary-bg);
  margin-bottom: 1rem;
}

.profile-info p {
  margin-bottom: 1rem;
  color: var(--slate-gray);
}

.achievement {
  background: rgba(100, 180, 255, 0.1);
  padding: 1.5rem;
  border-radius: 10px;
  margin-top: 2rem;
  border-left: 4px solid var(--accent-blue);
}

/* Footer - NeoAI.jp inspired */
footer {
  background: rgba(10, 10, 10, 0.9);
  color: var(--text-secondary);
  padding: 4rem 2rem 3rem;
  text-align: center;
  border-top: 1px solid var(--border-subtle);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
}

/* Social Links - NeoAI.jp inspired */
.social-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 2rem;
}

.social-links a {
  color: var(--text-secondary);
  font-size: 1.5rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  padding: 0.8rem;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
}

.social-links a:hover {
  color: var(--accent-cyan);
  background: rgba(0, 212, 255, 0.1);
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

/* Responsive Design */
@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .hero-content {
    padding: 1rem;
  }
  
  .about-content {
    grid-template-columns: 1fr;
    gap: 2rem;
    text-align: center;
  }
  
  .articles-grid {
    grid-template-columns: 1fr;
  }
  
  main {
    padding: 2rem 1rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  #hero-canvas {
    display: none;
  }
  
  .hero {
    background: var(--gradient-hero);
  }
  
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Utility Classes */
.text-center { text-align: center; }
.mb-4 { margin-bottom: 2rem; }
.mt-4 { margin-top: 2rem; }
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}
/* Article Card Link - クリック可能カード */
.article-card-link {
  display: block;
  text-decoration: none;
  color: inherit;
  cursor: pointer;
}

.article-card-link:hover {
  color: inherit;
  text-shadow: none;
}

.article-card-link .article-card {
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1),
              box-shadow 0.3s cubic-bezier(0.4, 0, 0.2, 1),
              border-color 0.3s ease;
}

.article-card-link:hover .article-card {
  transform: translateY(-8px);
  box-shadow: var(--shadow-hover);
  border-color: var(--border-glow);
  cursor: pointer;
}