:root {
  --navy: #1a2540;
  --navy-light: #2e3d60;
  --gold: oklch(68% 0.12 72);
  --gold-light: oklch(80% 0.10 72);
  --ivory: oklch(97.5% 0.008 80);
  --ivory-deep: oklch(93% 0.012 75);
  --text: #1a1a1a;
  --text-mid: #555;
  --text-light: #888;
  --serif: 'Noto Serif JP', serif;
  --sans: 'Noto Sans JP', sans-serif;
}

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

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

body.case-site {
  font-family: var(--sans);
  background: var(--ivory);
  color: var(--text);
  overflow-x: hidden;
}

body.case-site.disclaimer-open {
  overflow: hidden;
}

body.case-site.nav-open {
  overflow: hidden;
}

.case-site nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
}
.case-site .nav-logo {
  display: inline-flex;
  align-items: center;
  gap: 0;
  font-family: var(--serif);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-decoration: none;
}
.case-site .nav-logo-text {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  line-height: 1;
}
.case-site .nav-logo-corp {
  font-family: var(--sans);
  font-size: 0.58rem;
  font-weight: 400;
  letter-spacing: 0.28em;
  opacity: 0.72;
  padding-left: 0.12rem;
}
.case-site .nav-logo-ja {
  font-size: 1.18rem;
  letter-spacing: 0.18em;
}
.case-site .nav-links {
  display: flex; gap: 2.4rem; list-style: none; align-items: center;
}
.case-site .nav-item-trigger {
  display: flex;
  align-items: center;
}
.case-site .nav-item--services::after {
  content: '';
  position: absolute;
  top: 100%;
  left: -0.75rem;
  width: calc(100% + 1.5rem);
  height: 1rem;
}
.case-site .nav-links > li {
  position: relative;
}
.case-site .nav-links a {
  font-size: 0.82rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  text-decoration: none;
  transition: color 0.3s;
  position: relative;
}
.case-site .nav-item--services > a {
  display: inline-block;
  padding-right: 1rem;
}
.case-site .nav-item--services > a::before {
  content: '';
  position: absolute;
  top: 50%;
  right: 0;
  width: 0.42rem;
  height: 0.42rem;
  border-right: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
  transform: translateY(-62%) rotate(45deg);
  opacity: 0.72;
  transition: transform 0.3s ease;
}
.case-site .nav-item--services:hover > a::before,
.case-site .nav-item--services:focus-within > a::before {
  transform: translateY(-32%) rotate(225deg);
}
.case-site .nav-links a::after {
  content: ''; position: absolute; bottom: -3px; left: 0; width: 0; height: 1px;
  background: var(--gold); transition: width 0.3s;
}
.case-site .nav-links a:hover::after { width: 100%; }
.case-site .nav-item--services:hover > .nav-item-trigger > a::after,
.case-site .nav-item--services:focus-within > .nav-item-trigger > a::after {
  width: 100%;
}
.case-site .nav-submenu {
  position: absolute;
  top: calc(100% + 0.45rem);
  left: 50%;
  min-width: 15rem;
  padding: 0.7rem 0;
  list-style: none;
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 10px;
  background: rgba(14, 24, 44, 0.96);
  box-shadow: 0 18px 40px rgba(0,0,0,0.22);
  backdrop-filter: blur(12px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateX(-50%) translateY(8px);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s ease;
}
.case-site .nav-item--services:hover .nav-submenu,
.case-site .nav-item--services:focus-within .nav-submenu {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}
.case-site .nav-submenu li {
  width: 100%;
}
.case-site .nav-submenu a {
  display: block;
  padding: 0.75rem 1.1rem;
  letter-spacing: 0.04em;
  white-space: nowrap;
}
.case-site .nav-submenu a::after {
  display: none;
}
.case-site .nav-submenu a:hover {
  background: rgba(255,255,255,0.06);
}
.case-site .nav-submenu-toggle {
  display: none;
}
.case-site .nav-cta {
  background: var(--gold);
  color: #fff !important;
  padding: 0.55rem 1.4rem;
  border-radius: 2px;
  font-weight: 500 !important;
}
.case-site .nav-cta::after { display: none !important; }
.case-site .nav-cta:hover { background: var(--gold-light) !important; }

.case-site-page nav {
  padding: 1.5rem 4rem;
  background: rgba(255,255,255,0.97);
  box-shadow: 0 1px 24px rgba(0,0,0,0.07);
  backdrop-filter: blur(12px);
}
.case-site-home .nav-submenu a {
  color: rgba(255,255,255,0.88);
}
.case-site-home .site-header.is-open {
  background: rgba(255,255,255,0.98);
  box-shadow: 0 14px 36px rgba(18,30,51,0.16);
  backdrop-filter: blur(12px);
}
.case-site-home .site-header.is-open .nav-logo,
.case-site-home .site-header.is-open .nav-links a,
.case-site-home .site-header.is-open .hamburger,
.case-site-home .site-header.is-open .nav-submenu-toggle {
  color: var(--navy);
}
.case-site-home .site-header.is-open .nav-submenu a {
  color: var(--navy);
}
.case-site-home .site-header.is-open .hamburger,
.case-site-home .site-header.is-open .nav-submenu-toggle,
.case-site-home .site-header.is-open .nav-links {
  border-color: rgba(26,37,64,0.14);
}
.case-site-home .site-header.is-open .nav-submenu {
  border-left-color: rgba(26,37,64,0.12);
}
.case-site-home nav.scrolled .nav-submenu {
  border-color: rgba(26,37,64,0.08);
  background: rgba(255,255,255,0.98);
  box-shadow: 0 16px 36px rgba(18,30,51,0.14);
}
.case-site-home nav.scrolled .nav-submenu a {
  color: var(--text-mid);
}
.case-site-home nav.scrolled .nav-submenu a:hover {
  color: var(--navy);
  background: rgba(26,37,64,0.05);
}
.case-site-page .nav-logo {
  color: var(--navy);
}
.case-site-page .nav-links a { color: var(--text-mid); }
.case-site-page .nav-links a:hover { color: var(--navy); }
.case-site-page .nav-submenu {
  border-color: rgba(26,37,64,0.08);
  background: rgba(255,255,255,0.98);
  box-shadow: 0 16px 36px rgba(18,30,51,0.14);
}
.case-site-page .nav-submenu a {
  color: var(--text-mid);
}
.case-site-page .nav-submenu a:hover {
  color: var(--navy);
  background: rgba(26,37,64,0.05);
}
.case-site .hamburger {
  display: none;
  align-items: center;
  justify-content: center;
  width: 2.8rem;
  height: 2.8rem;
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 999px;
  background: transparent;
  cursor: pointer;
  flex-direction: column;
  gap: 0.3rem;
}
.case-site .hamburger span {
  width: 1.1rem;
  height: 1px;
  background: currentColor;
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.case-site-home .hamburger {
  color: rgba(255,255,255,0.92);
}
.case-site-home nav.scrolled .hamburger,
.case-site-page .hamburger {
  color: var(--navy);
  border-color: rgba(26,37,64,0.14);
}
.case-site .site-header.is-open .hamburger span:nth-child(1) {
  transform: translateY(0.4rem) rotate(45deg);
}
.case-site .site-header.is-open .hamburger span:nth-child(2) {
  opacity: 0;
}
.case-site .site-header.is-open .hamburger span:nth-child(3) {
  transform: translateY(-0.4rem) rotate(-45deg);
}
.case-site .sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.case-site footer {
  background: #111820;
  padding: 4rem 4rem 2.5rem;
}
.case-site .footer-inner {
  max-width: 1200px; margin: 0 auto;
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 4rem;
  padding-bottom: 3rem; border-bottom: 1px solid rgba(255,255,255,0.06);
}
.case-site .footer-brand h3 {
  font-family: var(--serif); font-size: 1.1rem;
  color: #fff; margin-bottom: 0.8rem; letter-spacing: 0.04em;
}
.case-site .footer-brand p { font-size: 0.78rem; color: rgba(255,255,255,0.35); line-height: 2; }
.case-site .footer-col h4 {
  font-size: 0.72rem; letter-spacing: 0.18em;
  color: rgba(255,255,255,0.4); text-transform: uppercase;
  margin-bottom: 1.2rem;
}
.case-site .footer-col a {
  display: block; font-size: 0.8rem;
  color: rgba(255,255,255,0.55); text-decoration: none;
  margin-bottom: 0.7rem; letter-spacing: 0.04em;
  transition: color 0.3s;
}
.case-site .footer-col a:hover { color: var(--gold); }
.case-site .footer-bottom {
  max-width: 1200px; margin: 2rem auto 0;
  display: flex; justify-content: space-between; align-items: center;
}
.case-site .footer-bottom p {
  font-size: 0.72rem; color: rgba(255,255,255,0.25); letter-spacing: 0.08em;
  line-height: 1.8;
}
.case-site .footer-bottom a {
  font-size: 0.72rem; color: rgba(255,255,255,0.4); text-decoration: none; transition: color 0.3s;
  line-height: 1.8; overflow-wrap: anywhere;
}
.case-site .footer-bottom a:hover { color: var(--gold); }

@media (max-width: 900px) {
  .case-site .nav-item--services::after {
    display: none;
  }
  .case-site nav {
    padding: 1.2rem 1.5rem;
    align-items: center;
    flex-wrap: wrap;
  }
  .case-site .nav-logo-text { gap: 0.14rem; }
  .case-site .nav-logo-corp {
    font-size: 0.5rem;
    letter-spacing: 0.2em;
  }
  .case-site .nav-logo-ja {
    font-size: 0.98rem;
    letter-spacing: 0.12em;
  }
  .case-site .hamburger {
    display: inline-flex;
  }
  .case-site .nav-links {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin-top: 1rem;
    padding: 1rem 0 0;
    border-top: 1px solid rgba(255,255,255,0.1);
  }
  .case-site .site-header.is-open .nav-links {
    display: flex;
  }
  .case-site-page .nav-links,
  .case-site-home nav.scrolled .nav-links {
    border-top-color: rgba(26,37,64,0.1);
  }
  .case-site .nav-links > li {
    width: 100%;
  }
  .case-site .nav-links > li > a,
  .case-site .nav-item-trigger > a {
    display: block;
    width: 100%;
    padding: 0.95rem 0;
  }
  .case-site .nav-links a::after {
    display: none;
  }
  .case-site .nav-item-trigger {
    width: 100%;
    justify-content: space-between;
    gap: 1rem;
  }
  .case-site .nav-item--services > a {
    padding-right: 0;
  }
  .case-site .nav-item--services > a::before {
    display: none;
  }
  .case-site .nav-submenu-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 0 0 auto;
    width: 2.5rem;
    height: 2.5rem;
    border: 1px solid rgba(255,255,255,0.16);
    border-radius: 999px;
    background: transparent;
    color: inherit;
    cursor: pointer;
  }
  .case-site-page .nav-submenu-toggle,
  .case-site-home nav.scrolled .nav-submenu-toggle {
    border-color: rgba(26,37,64,0.14);
  }
  .case-site .nav-submenu-toggle::before {
    content: '';
    width: 0.5rem;
    height: 0.5rem;
    border-right: 1px solid currentColor;
    border-bottom: 1px solid currentColor;
    transform: translateY(-0.1rem) rotate(45deg);
    transition: transform 0.25s ease;
  }
  .case-site .nav-item--services.is-open .nav-submenu-toggle::before {
    transform: translateY(0.08rem) rotate(225deg);
  }
  .case-site .nav-submenu {
    position: static;
    min-width: 0;
    margin: 0;
    padding: 0.2rem 0 0.5rem 1rem;
    border: 0;
    border-left: 1px solid rgba(255,255,255,0.14);
    border-radius: 0;
    background: transparent;
    box-shadow: none;
    backdrop-filter: none;
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: none;
    display: none;
  }
  .case-site-page .nav-submenu,
  .case-site-home nav.scrolled .nav-submenu {
    border-left-color: rgba(26,37,64,0.12);
  }
  .case-site .nav-item--services.is-open .nav-submenu {
    display: block;
    transform: none;
    box-shadow: none;
  }
  .case-site .nav-submenu a {
    padding: 0.75rem 0;
    white-space: normal;
  }
  .case-site .nav-submenu a:hover {
    background: transparent;
  }
  .case-site .nav-cta {
    display: block;
    margin-top: 0.75rem;
    padding: 0.9rem 1rem;
    text-align: center;
  }
  .case-site footer { padding: 2.5rem 1.5rem 2rem; }
  .case-site .footer-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 2rem 1.5rem;
  }
  .case-site .footer-brand {
    grid-column: 1 / -1;
    max-width: 32rem;
  }
  .case-site .footer-bottom { flex-direction: column; align-items: flex-start; gap: 0.75rem; }
}

@media (max-width: 640px) {
  .case-site footer { padding: 2rem 1.25rem 1.75rem; }
  .case-site .footer-inner {
    grid-template-columns: 1fr;
    gap: 1.75rem;
    padding-bottom: 2rem;
  }
  .case-site .footer-brand {
    grid-column: auto;
    max-width: none;
  }
  .case-site .footer-col h4 { margin-bottom: 0.8rem; }
  .case-site .footer-col a { margin-bottom: 0.6rem; }
  .case-site .footer-bottom {
    margin-top: 1.5rem;
    gap: 0.5rem;
  }
}