/* ===== AMANE Terms of Service - Stylesheet ===== */

/* Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@300;400;500;700&family=Inter:wght@300;400;500;600;700&display=swap');

/* CSS Custom Properties */
:root {
  /* Colors - AMANE Brand */
  --color-bg-primary: #0a0a1a;
  --color-bg-secondary: #12122a;
  --color-bg-card: rgba(255, 255, 255, 0.04);
  --color-bg-card-hover: rgba(255, 255, 255, 0.07);
  --color-border: rgba(255, 255, 255, 0.08);
  --color-border-accent: rgba(139, 92, 246, 0.3);

  --color-text-primary: #e8e8f0;
  --color-text-secondary: #9ca3af;
  --color-text-muted: #6b7280;
  --color-text-heading: #f5f5ff;

  --color-accent-purple: #8b5cf6;
  --color-accent-pink: #ec4899;
  --color-accent-blue: #6366f1;

  --gradient-brand: linear-gradient(135deg, #8b5cf6 0%, #ec4899 50%, #6366f1 100%);
  --gradient-bg: linear-gradient(180deg, #0a0a1a 0%, #12122a 40%, #1a1040 100%);
  --gradient-glow: radial-gradient(ellipse 600px 400px at 50% 0%, rgba(139, 92, 246, 0.12) 0%, transparent 70%);

  /* Typography */
  --font-sans: 'Noto Sans JP', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;

  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Border Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Shadows */
  --shadow-glow: 0 0 30px rgba(139, 92, 246, 0.15);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.3);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.8;
  color: var(--color-text-primary);
  background: var(--gradient-bg);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ===== Background Effects ===== */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 600px;
  background: var(--gradient-glow);
  pointer-events: none;
  z-index: 0;
}

/* ===== Layout ===== */
.page-wrapper {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: var(--space-4) var(--space-6);
  background: rgba(10, 10, 26, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  transition: background var(--transition-base);
}

.header-inner {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text-heading);
}

.logo-text {
  font-size: var(--font-size-xl);
  font-weight: 700;
  letter-spacing: 0.08em;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.logo-divider {
  width: 1px;
  height: 20px;
  background: var(--color-border);
}

.logo-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  font-weight: 400;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  list-style: none;
}

.nav-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: var(--font-size-sm);
  font-weight: 500;
  transition: color var(--transition-fast);
  position: relative;
}

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

.nav-links a.active {
  color: var(--color-accent-purple);
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--gradient-brand);
  border-radius: 1px;
}

/* ===== Main Content ===== */
.main-content {
  flex: 1;
  max-width: 900px;
  width: 100%;
  margin: 0 auto;
  padding: var(--space-12) var(--space-6) var(--space-16);
}

/* ===== Hero Section ===== */
.hero {
  text-align: center;
  margin-bottom: var(--space-12);
  padding: var(--space-12) 0 var(--space-8);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: rgba(139, 92, 246, 0.1);
  border: 1px solid rgba(139, 92, 246, 0.2);
  border-radius: 999px;
  font-size: var(--font-size-xs);
  color: var(--color-accent-purple);
  font-weight: 500;
  margin-bottom: var(--space-6);
  letter-spacing: 0.05em;
}

.hero-badge-dot {
  width: 6px;
  height: 6px;
  background: var(--color-accent-purple);
  border-radius: 50%;
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.8); }
}

.hero h1 {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  color: var(--color-text-heading);
  line-height: 1.2;
  margin-bottom: var(--space-4);
}

.hero-description {
  font-size: var(--font-size-lg);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
  line-height: 1.7;
}

.hero-meta {
  display: flex;
  justify-content: center;
  gap: var(--space-8);
  margin-top: var(--space-8);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
}

.hero-meta-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-1);
}

.hero-meta-label {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 500;
}

.hero-meta-value {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  font-weight: 500;
}

/* ===== Table of Contents ===== */
.toc {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6) var(--space-8);
  margin-bottom: var(--space-10);
  transition: border-color var(--transition-base);
}

.toc:hover {
  border-color: var(--color-border-accent);
}

.toc-title {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-4);
}

.toc-list {
  list-style: none;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2) var(--space-8);
}

.toc-list a {
  color: var(--color-text-secondary);
  text-decoration: none;
  font-size: var(--font-size-sm);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) 0;
  transition: all var(--transition-fast);
  border-radius: var(--radius-sm);
}

.toc-list a:hover {
  color: var(--color-accent-purple);
  padding-left: var(--space-2);
}

.toc-list a::before {
  content: '';
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--color-accent-purple);
  opacity: 0.5;
  flex-shrink: 0;
  transition: opacity var(--transition-fast);
}

.toc-list a:hover::before {
  opacity: 1;
}

/* ===== Sections ===== */
.terms-section {
  margin-bottom: var(--space-10);
  padding-bottom: var(--space-10);
  border-bottom: 1px solid var(--color-border);
  animation: fadeInUp 0.5s ease both;
}

.terms-section:last-child {
  border-bottom: none;
}

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

.terms-section h2 {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--color-text-heading);
  margin-bottom: var(--space-6);
  display: flex;
  align-items: center;
  gap: var(--space-3);
  scroll-margin-top: 80px;
}

.section-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: rgba(139, 92, 246, 0.1);
  color: var(--color-accent-purple);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-sm);
  font-weight: 700;
  flex-shrink: 0;
}

.terms-section h3 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-text-heading);
  margin-top: var(--space-6);
  margin-bottom: var(--space-3);
}

.terms-section p {
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
  line-height: 1.9;
}

.terms-section ul,
.terms-section ol {
  color: var(--color-text-secondary);
  margin-bottom: var(--space-4);
  padding-left: var(--space-6);
}

.terms-section li {
  margin-bottom: var(--space-2);
  line-height: 1.8;
}

.terms-section li::marker {
  color: var(--color-accent-purple);
}

/* ===== Highlight Box ===== */
.highlight-box {
  background: rgba(139, 92, 246, 0.06);
  border-left: 3px solid var(--color-accent-purple);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: var(--space-5) var(--space-6);
  margin: var(--space-6) 0;
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  line-height: 1.8;
}

.highlight-box strong {
  color: var(--color-text-primary);
}

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-8) var(--space-6);
  background: rgba(10, 10, 26, 0.6);
}

.footer-inner {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-brand {
  font-size: var(--font-size-sm);
  font-weight: 600;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

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

.footer-links {
  display: flex;
  gap: var(--space-6);
  list-style: none;
}

.footer-links a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: var(--font-size-xs);
  transition: color var(--transition-fast);
}

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

/* ===== Back to Top ===== */
.back-to-top {
  position: fixed;
  bottom: var(--space-8);
  right: var(--space-8);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(139, 92, 246, 0.15);
  border: 1px solid rgba(139, 92, 246, 0.3);
  border-radius: 50%;
  color: var(--color-accent-purple);
  text-decoration: none;
  font-size: var(--font-size-lg);
  transition: all var(--transition-base);
  opacity: 0;
  pointer-events: none;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  z-index: 50;
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  background: rgba(139, 92, 246, 0.25);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero h1 {
    font-size: var(--font-size-3xl);
  }

  .hero-meta {
    flex-direction: column;
    gap: var(--space-4);
  }

  .toc-list {
    grid-template-columns: 1fr;
  }

  .main-content {
    padding: var(--space-8) var(--space-4) var(--space-12);
  }

  .header-inner {
    flex-direction: column;
    gap: var(--space-3);
  }

  .nav-links {
    gap: var(--space-4);
  }

  .footer-inner {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }

  .terms-section h2 {
    font-size: var(--font-size-xl);
  }
}

@media (max-width: 480px) {
  .hero {
    padding: var(--space-8) 0 var(--space-6);
  }

  .hero h1 {
    font-size: var(--font-size-2xl);
  }

  .toc {
    padding: var(--space-4) var(--space-5);
  }

  .logo-divider,
  .logo-subtitle {
    display: none;
  }
}