/* ============================================
   ShareTech - Global Design System
   ============================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Noto+Sans+JP:wght@300;400;500;600;700;800;900&display=swap');

/* --- CSS Custom Properties (Design Tokens) --- */
:root {
  /* Colors - Bright Modern IT Theme */
  --color-primary: #0F172A;
  --color-primary-light: #1E293B;
  --color-primary-dark: #020617;
  --color-accent: #3B82F6;
  --color-accent-hover: #2563EB;
  --color-accent-light: #60A5FA;
  --color-accent-glow: rgba(59, 130, 246, 0.35);
  --color-accent-subtle: rgba(59, 130, 246, 0.12);
  --color-surface: #1E293B;
  --color-surface-light: #334155;
  --color-surface-lighter: #475569;
  --color-border: rgba(148, 163, 184, 0.15);
  --color-border-light: rgba(148, 163, 184, 0.25);
  --color-text: #F1F5F9;
  --color-text-secondary: #CBD5E1;
  --color-text-muted: #94A3B8;
  --color-text-dim: #64748B;
  --color-success: #22C55E;
  --color-warning: #FBBF24;
  --color-error: #F87171;
  --color-white: #FFFFFF;

  /* Gradients - Brighter & More Vibrant */
  --gradient-primary: linear-gradient(135deg, #3B82F6 0%, #8B5CF6 50%, #06B6D4 100%);
  --gradient-primary-hover: linear-gradient(135deg, #2563EB 0%, #7C3AED 50%, #0891B2 100%);
  --gradient-dark: linear-gradient(180deg, #0F172A 0%, #1E293B 100%);
  --gradient-hero: linear-gradient(135deg, #0F172A 0%, #1E3A5F 40%, #164E63 100%);
  --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.07) 0%, rgba(255,255,255,0.03) 100%);
  --gradient-glow: radial-gradient(ellipse at center, rgba(59, 130, 246, 0.2) 0%, transparent 70%);

  /* Typography */
  --font-primary: 'Inter', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Inter', 'Noto Sans JP', sans-serif;
  
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;

  --weight-light: 300;
  --weight-regular: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;
  --weight-extrabold: 800;

  --leading-tight: 1.25;
  --leading-normal: 1.6;
  --leading-relaxed: 1.75;

  /* 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;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.3);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 30px rgba(37, 99, 235, 0.3);
  --shadow-glow-lg: 0 0 60px rgba(37, 99, 235, 0.2);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
  --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

  /* Layout */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1200px;
  --container-2xl: 1400px;
  --header-height: 80px;

  /* Z-index */
  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-header: 300;
  --z-overlay: 400;
  --z-modal: 500;
  --z-tooltip: 600;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-primary);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

a:hover {
  color: var(--color-accent);
}

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

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: var(--weight-bold);
  line-height: var(--leading-tight);
  color: var(--color-text);
}

/* --- Typography --- */
.text-gradient {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h1, .h1 { font-size: var(--text-5xl); font-weight: var(--weight-extrabold); }
h2, .h2 { font-size: var(--text-4xl); font-weight: var(--weight-bold); }
h3, .h3 { font-size: var(--text-2xl); font-weight: var(--weight-semibold); }
h4, .h4 { font-size: var(--text-xl); font-weight: var(--weight-semibold); }
h5, .h5 { font-size: var(--text-lg); font-weight: var(--weight-medium); }
h6, .h6 { font-size: var(--text-base); font-weight: var(--weight-medium); }

.text-sm { font-size: var(--text-sm); }
.text-lg { font-size: var(--text-lg); }
.text-xl { font-size: var(--text-xl); }
.text-muted { color: var(--color-text-muted); }
.text-secondary { color: var(--color-text-secondary); }
.text-accent { color: var(--color-accent-light); }

/* --- Layout --- */
.container {
  width: 100%;
  max-width: var(--container-xl);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.container-sm {
  max-width: var(--container-md);
}

.container-lg {
  max-width: var(--container-2xl);
}

.section {
  padding: var(--space-24) 0;
  position: relative;
}

.section-sm {
  padding: var(--space-16) 0;
}

.section-lg {
  padding: var(--space-32) 0;
}

/* --- Grid System --- */
.grid {
  display: grid;
  gap: var(--space-6);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* --- Flexbox Utilities --- */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }
.gap-12 { gap: var(--space-12); }

/* --- Text Alignment --- */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

/* --- Margin & Padding Utilities --- */
.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }
.mx-auto { margin-left: auto; margin-right: auto; }

/* --- Section Header --- */
.section-header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section-header h2 {
  margin-bottom: var(--space-4);
  position: relative;
  display: inline-block;
}

.section-header h2::after {
  content: '';
  position: absolute;
  bottom: -12px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
}

.section-header .section-subtitle {
  color: var(--color-text-muted);
  font-size: var(--text-lg);
  max-width: 600px;
  margin: var(--space-6) auto 0;
}

.section-label {
  display: inline-block;
  color: var(--color-accent-light);
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-3);
}

/* --- Glassmorphism Base --- */
.glass {
  background: rgba(255, 255, 255, 0.03);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--color-border);
}

.glass-strong {
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(30px);
  -webkit-backdrop-filter: blur(30px);
  border: 1px solid var(--color-border-light);
}

/* --- Scroll Animation Classes --- */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

.fade-in-left {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-left.visible {
  opacity: 1;
  transform: translateX(0);
}

.fade-in-right {
  opacity: 0;
  transform: translateX(40px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-right.visible {
  opacity: 1;
  transform: translateX(0);
}

.scale-in {
  opacity: 0;
  transform: scale(0.9);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.scale-in.visible {
  opacity: 1;
  transform: scale(1);
}

/* Stagger children */
.stagger-children .fade-in:nth-child(1) { transition-delay: 0ms; }
.stagger-children .fade-in:nth-child(2) { transition-delay: 100ms; }
.stagger-children .fade-in:nth-child(3) { transition-delay: 200ms; }
.stagger-children .fade-in:nth-child(4) { transition-delay: 300ms; }
.stagger-children .fade-in:nth-child(5) { transition-delay: 400ms; }
.stagger-children .fade-in:nth-child(6) { transition-delay: 500ms; }
.stagger-children .fade-in:nth-child(7) { transition-delay: 600ms; }
.stagger-children .fade-in:nth-child(8) { transition-delay: 700ms; }

/* --- Background Decorations --- */
.bg-dots {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 30px 30px;
  pointer-events: none;
}

.bg-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: var(--gradient-glow);
  filter: blur(80px);
  pointer-events: none;
  z-index: 0;
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  :root {
    --text-5xl: 2.5rem;
    --text-6xl: 3rem;
  }

  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }

  .section { padding: var(--space-16) 0; }
  .section-lg { padding: var(--space-24) 0; }
}

@media (max-width: 768px) {
  :root {
    --text-4xl: 1.875rem;
    --text-5xl: 2.25rem;
    --text-6xl: 2.5rem;
    --header-height: 64px;
  }

  .container {
    padding: 0 var(--space-4);
  }

  .grid-4 { grid-template-columns: 1fr; }
  .grid-3 { grid-template-columns: 1fr; }
  .grid-2 { grid-template-columns: 1fr; }

  .section { padding: var(--space-12) 0; }
  .section-lg { padding: var(--space-16) 0; }

  .section-header {
    margin-bottom: var(--space-10);
  }

  h1, .h1 { font-size: var(--text-4xl); }
  h2, .h2 { font-size: var(--text-3xl); }
}

@media (max-width: 480px) {
  :root {
    --text-3xl: 1.5rem;
    --text-4xl: 1.75rem;
    --text-5xl: 2rem;
  }
}