/* CSS Variables */
:root {
  /* Colors */
  --color-bg-primary: #000;
  --color-text-primary: #fff;
  --color-accent: #0066cc;
  --color-header-bg: rgba(0, 0, 0, 0);
  
  /* Layout */
  --container-max-width: 1152px;
  --header-height: 70px;
  --footer-height: 310px;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 3rem;
  --spacing-xl: 4rem;
  
  /* Transitions */
  --transition-base: 0.3s ease;
}

/* Base Styles */
body {
  background-color: var(--color-bg-primary);
  color: var(--color-text-primary);
  font-family: 'Noto Sans JP', sans-serif;
  line-height: 1.8;
  letter-spacing: 0.08em;
  overflow-x: hidden;
  margin: 0;
  padding: 0;
}

/* Container */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

@media (max-width: 576px) {
  .container {
    padding: 0 var(--spacing-sm);
  }
}

/* Fade-in Animation */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Section Spacing */
section {
  padding: var(--spacing-xl) 0;
}

/* Hero section has no padding */
section.hero {
  padding: 0;
}

@media (max-width: 768px) {
  section {
    padding: var(--spacing-lg) 0;
  }
  
  section.hero {
    padding: 0;
  }
}

@media (max-width: 576px) {
  section {
    padding: var(--spacing-md) 0;
  }
  
  section.hero {
    padding: 0;
  }
}

/* Section Title */
.section-title {
  font-size: clamp(1.5rem, 3vw, 2.5rem);
  font-weight: bold;
  margin-bottom: var(--spacing-md);
  text-align: center;
}