:root {
  /* Colors */
  --c-white: #ffffff;
  --c-bg: #f8fafc;
  --c-navy: #0f172a;
  --c-navy-light: #1e293b;
  --c-blue: #2563eb;
  --c-blue-hover: #1d4ed8;
  --c-blue-light: #eff6ff;
  --c-text-main: #334155;
  --c-text-muted: #64748b;
  --c-border: #e2e8f0;

  /* Typography */
  --font-base: 'Inter', 'Noto Sans JP', sans-serif;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-glass: 0 8px 32px 0 rgba(15, 23, 42, 0.05);

  /* Transitions */
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Container */
  --container-w: 1200px;
  --header-h: 80px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-base);
  color: var(--c-text-main);
  background-color: var(--c-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

ul, ol {
  list-style: none;
}

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

/* Utilities */
.container {
  width: 100%;
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 0 24px;
}

.text-gradient {
  background: linear-gradient(135deg, var(--c-navy) 0%, var(--c-blue) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section {
  padding: 100px 0;
}

.section-title {
  text-align: center;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--c-navy);
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.section-subtitle {
  text-align: center;
  font-size: 1.125rem;
  color: var(--c-blue);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 3rem;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 50px;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  gap: 8px;
}

.btn-primary {
  background-color: var(--c-blue);
  color: var(--c-white);
  box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.39);
}

.btn-primary:hover {
  background-color: var(--c-blue-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px 0 rgba(37, 99, 235, 0.39);
}

.btn-secondary {
  background-color: var(--c-white);
  color: var(--c-navy);
  border: 1px solid var(--c-border);
}

.btn-secondary:hover {
  border-color: var(--c-blue);
  color: var(--c-blue);
  transform: translateY(-2px);
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.6);
  z-index: 1000;
  transition: var(--transition);
}

.header.is-scrolled {
  box-shadow: var(--shadow-sm);
  background: rgba(255, 255, 255, 0.95);
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--c-navy);
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo span {
  color: var(--c-blue);
}

.global-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.global-nav a {
  font-weight: 500;
  color: var(--c-text-main);
  font-size: 0.9375rem;
  position: relative;
}

.global-nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--c-blue);
  transition: var(--transition);
}

.global-nav a:hover {
  color: var(--c-blue);
}

.global-nav a:hover::after {
  width: 100%;
}

.nav-contact-btn {
  background-color: var(--c-navy);
  color: var(--c-white) !important;
  padding: 10px 24px;
  border-radius: 50px;
}

.nav-contact-btn::after {
  display: none;
}

.nav-contact-btn:hover {
  background-color: var(--c-blue);
  transform: translateY(-2px);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 24px;
  height: 20px;
  background: none;
  border: none;
  cursor: pointer;
  z-index: 1001;
  position: relative;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--c-navy);
  transition: var(--transition);
}

/* Footer */
.footer {
  background-color: var(--c-navy);
  color: var(--c-white);
  padding: 80px 0 40px;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 60px;
  margin-bottom: 60px;
}

.footer-logo {
  font-size: 1.75rem;
  font-weight: 800;
  margin-bottom: 16px;
  display: inline-block;
}

.footer-desc {
  color: #94a3b8;
  max-width: 320px;
  margin-bottom: 24px;
}

.footer-links h4 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--c-white);
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  color: #94a3b8;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--c-blue);
  padding-left: 4px;
}

.footer-bottom {
  text-align: center;
  padding-top: 40px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: #94a3b8;
  font-size: 0.875rem;
}

/* Animations */
.fade-up {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

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

.delay-100 { transition-delay: 0.1s; }
.delay-200 { transition-delay: 0.2s; }
.delay-300 { transition-delay: 0.3s; }

/* Responsive */
@media (max-width: 992px) {
  .footer-top {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .section {
    padding: 60px 0;
  }
  
  .section-title {
    font-size: 2rem;
  }
  
  .menu-toggle {
    display: flex;
  }

  .global-nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 100%;
    height: 100vh;
    background-color: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    flex-direction: column;
    justify-content: center;
    transition: var(--transition);
    padding: 24px;
  }

  .global-nav.is-active {
    right: 0;
  }

  .global-nav a {
    font-size: 1.25rem;
  }

  .menu-toggle.is-active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
  }
  
  .menu-toggle.is-active span:nth-child(2) {
    opacity: 0;
  }
  
  .menu-toggle.is-active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 40px;
  }
}