:root {
      --bg: #fbfcfe;
      --surface: rgba(255, 255, 255, 0.94);
      --surface-soft: #f5f9fd;
      --ink: #16375f;
      --ink-soft: #4a6887;
      --line: rgba(29, 83, 140, 0.12);
      --line-strong: rgba(29, 83, 140, 0.22);
      --blue-1: #49c4ef;
      --blue-2: #2d95d2;
      --blue-3: #1a5eb0;
      --blue-4: #163f86;
      --signal: #f53a0a;
      --shadow: 0 18px 44px rgba(18, 60, 110, 0.08);
      --max: 1120px;
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      color: var(--ink);
      background:
        radial-gradient(circle at top left, rgba(73, 196, 239, 0.08), transparent 28%),
        radial-gradient(circle at top right, rgba(26, 94, 176, 0.06), transparent 24%),
        linear-gradient(180deg, #fdfefe 0%, #f8fbfe 56%, #f5f8fc 100%);
      font-family: "Hiragino Sans", "Yu Gothic", "Meiryo", sans-serif;
      line-height: 1.8;
      letter-spacing: 0.01em;
    }

    body::before {
      content: "";
      position: fixed;
      inset: 0;
      pointer-events: none;
      background:
        linear-gradient(rgba(22, 63, 134, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(22, 63, 134, 0.02) 1px, transparent 1px);
      background-size: 32px 32px;
      mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.16), transparent 92%);
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    body [data-lang] {
      display: none;
    }

    body[data-lang="en"] [data-lang="en"],
    body[data-lang="ja"] [data-lang="ja"] {
      display: revert;
    }

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

    .shell {
      width: min(calc(100% - 40px), var(--max));
      margin: 0 auto;
    }

    .site-header {
      position: sticky;
      top: 0;
      z-index: 30;
      background: rgba(251, 252, 254, 0.9);
      backdrop-filter: blur(14px);
      border-bottom: 1px solid rgba(29, 83, 140, 0.08);
    }

    .site-header .shell {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 24px;
      padding: 16px 0;
      flex-wrap: wrap;
    }

    .brand {
      display: flex;
      align-items: center;
      gap: 14px;
    }

    .brand-logo {
      width: 50px;
      height: 50px;
      padding: 5px;
      border-radius: 14px;
      background: rgba(255, 255, 255, 0.9);
      border: 1px solid rgba(29, 83, 140, 0.08);
      box-shadow: 0 10px 24px rgba(18, 60, 110, 0.05);
    }

    .brand-copy {
      display: grid;
      gap: 2px;
    }

    .brand-mark {
      font-size: 0.75rem;
      letter-spacing: 0.16em;
      text-transform: uppercase;
      color: var(--ink-soft);
    }

    .brand-name {
      font-size: 1.22rem;
      font-weight: 700;
      letter-spacing: 0.02em;
    }

    .site-nav {
      display: flex;
      gap: 18px;
      align-items: center;
      color: var(--ink-soft);
      font-size: 0.95rem;
    }

    .header-actions {
      display: flex;
      align-items: center;
      gap: 18px;
    }

    .menu-toggle {
      display: none;
      align-items: center;
      gap: 10px;
      appearance: none;
      border: 1px solid rgba(29, 83, 140, 0.12);
      background: rgba(255, 255, 255, 0.84);
      color: var(--blue-4);
      border-radius: 999px;
      min-height: 44px;
      padding: 0 14px;
      font: inherit;
      cursor: pointer;
      box-shadow: 0 10px 22px rgba(18, 60, 110, 0.05);
    }

    .menu-toggle-label {
      font-size: 0.9rem;
      font-weight: 600;
    }

    .menu-toggle-icon {
      position: relative;
      width: 18px;
      height: 14px;
      display: inline-block;
    }

    .menu-toggle-icon::before {
      content: "";
      position: absolute;
      left: 0;
      width: 100%;
      top: 1px;
      border-top: 2px solid currentColor;
      box-shadow: 0 5px 0 currentColor, 0 10px 0 currentColor;
    }

    .language-switcher {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 7px 9px;
      border-radius: 999px;
      background: rgba(255, 255, 255, 0.78);
      border: 1px solid rgba(29, 83, 140, 0.12);
      box-shadow: 0 10px 22px rgba(18, 60, 110, 0.05);
    }

    .language-switcher-label {
      font-size: 0.82rem;
      font-weight: 600;
      color: var(--ink-soft);
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    .language-switcher button {
      appearance: none;
      border: 0;
      background: transparent;
      color: var(--ink-soft);
      font: inherit;
      font-size: 0.9rem;
      padding: 6px 12px;
      border-radius: 999px;
      cursor: pointer;
      transition: background-color 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
    }

    .language-switcher button.is-active {
      background: linear-gradient(90deg, rgba(26, 94, 176, 0.92), rgba(45, 149, 210, 0.92));
      color: #fff;
      box-shadow: 0 8px 18px rgba(26, 94, 176, 0.18);
    }

    .site-nav a {
      position: relative;
      padding: 6px 0;
    }

    .site-nav a::after {
      content: "";
      position: absolute;
      left: 0;
      bottom: 0;
      width: 100%;
      height: 1px;
      background: linear-gradient(90deg, var(--blue-2), transparent);
      transform: scaleX(0);
      transform-origin: left;
      transition: transform 0.22s ease;
    }

    .site-nav a:hover::after,
    .site-nav a:focus-visible::after {
      transform: scaleX(1);
    }

    .hero {
      padding: 64px 0 32px;
    }

    .hero-card,
    .section-card,
    .sample-card {
      background: var(--surface);
      border: 1px solid var(--line);
      box-shadow: var(--shadow);
      backdrop-filter: blur(10px);
    }

    .hero-card {
      display: grid;
      grid-template-columns: minmax(0, 1.15fr) minmax(220px, 0.55fr);
      gap: 28px;
      align-items: center;
      padding: 40px;
      border-radius: 28px;
      background: linear-gradient(145deg, rgba(255, 255, 255, 0.97), rgba(247, 251, 255, 0.93));
    }

    .eyebrow {
      display: inline-flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 18px;
      font-size: 0.8rem;
      font-weight: 600;
      letter-spacing: 0.16em;
      color: var(--blue-3);
      text-transform: uppercase;
    }

    .eyebrow::before {
      content: "";
      width: 40px;
      height: 1px;
      background: linear-gradient(90deg, var(--blue-1), var(--blue-3));
    }

    h1,
    h2,
    h3,
    p {
      margin: 0;
    }

    h1,
    h2 {
      font-family: "Hiragino Mincho ProN", "Yu Mincho", serif;
      letter-spacing: -0.02em;
    }

    h1 {
      font-size: clamp(2.7rem, 5vw, 4.6rem);
      line-height: 1.08;
    }

    h2 {
      font-size: clamp(1.9rem, 3vw, 2.6rem);
      line-height: 1.24;
    }

    h3 {
      font-size: 1.22rem;
      line-height: 1.4;
    }

    .hero-lead {
      margin-top: 20px;
      max-width: 60ch;
      font-size: 1.05rem;
      color: var(--ink-soft);
    }

    .hero-side {
      display: grid;
      gap: 14px;
      justify-items: center;
      text-align: center;
    }

    .hero-logo {
      width: min(100%, 230px);
      padding: 12px;
      border-radius: 24px;
      background: rgba(255, 255, 255, 0.92);
      border: 1px solid rgba(29, 83, 140, 0.08);
      box-shadow: 0 12px 30px rgba(18, 60, 110, 0.05);
    }

    .hero-caption {
      max-width: 22ch;
      font-size: 0.92rem;
      color: var(--ink-soft);
    }

    .section {
      padding: 28px 0;
    }

    .section-card {
      border-radius: 26px;
      padding: 32px;
    }

    .section-head {
      display: block;
      margin-bottom: 24px;
    }

    .atlas-intro {
      display: grid;
      gap: 14px;
      max-width: 78ch;
    }

    .atlas-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 18px;
      margin-top: 22px;
    }

    .atlas-card {
      padding: 22px;
      border-radius: 22px;
      background: linear-gradient(145deg, rgba(255, 255, 255, 0.97), rgba(242, 248, 253, 0.94));
      border: 1px solid var(--line);
      box-shadow: 0 14px 34px rgba(18, 60, 110, 0.06);
    }

    .atlas-card h3 {
      color: var(--blue-4);
    }

    .atlas-card p {
      margin-top: 10px;
      font-size: 0.96rem;
      color: var(--ink-soft);
    }

    .atlas-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 16px;
    }

    .atlas-tags span {
      display: inline-flex;
      align-items: center;
      min-height: 30px;
      padding: 0 10px;
      border-radius: 999px;
      background: rgba(26, 94, 176, 0.08);
      border: 1px solid rgba(26, 94, 176, 0.1);
      color: var(--blue-4);
      font-size: 0.82rem;
      letter-spacing: 0.03em;
    }

    .atlas-future {
      margin-top: 24px;
      padding-top: 24px;
      border-top: 1px solid rgba(29, 83, 140, 0.08);
      max-width: 76ch;
    }

    .atlas-future p {
      margin-top: 10px;
    }


    .case-group + .case-group {
      margin-top: 26px;
      padding-top: 26px;
      border-top: 1px solid rgba(29, 83, 140, 0.08);
    }

    .case-title {
      margin-bottom: 16px;
      font-size: 1.08rem;
      color: var(--blue-4);
      letter-spacing: 0.02em;
    }


    .samples-grid {
      display: grid;
      gap: 18px;
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .sample-card {
      border-radius: 22px;
      padding: 20px;
      overflow: hidden;
    }

    .sample-card::before {
      content: "";
      display: block;
      width: 100%;
      height: 3px;
      margin: -20px -20px 18px;
      background: linear-gradient(90deg, var(--blue-2), var(--blue-4));
    }




    .sample-image {
      display: grid;
      place-items: center;
      aspect-ratio: 16 / 10;
      border-radius: 16px;
      margin-bottom: 16px;
      background:
        radial-gradient(circle at top left, rgba(73, 196, 239, 0.16), transparent 32%),
        linear-gradient(145deg, #f8fbff, #eef5fb);
      border: 1px solid rgba(29, 83, 140, 0.08);
      color: var(--blue-3);
      font-weight: 700;
      letter-spacing: 0.08em;
    }

    .sample-card p {
      margin-top: 10px;
      font-size: 0.96rem;
    }

    .about-body {
      display: grid;
      gap: 16px;
      max-width: 74ch;
    }


    .contact-links {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 12px;
      margin-top: 18px;
    }

    .button {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-height: 44px;
      padding: 0 18px;
      border-radius: 999px;
      border: 1px solid transparent;
      font-size: 0.95rem;
    }

    .button.primary {
      background: linear-gradient(90deg, rgba(26, 94, 176, 0.92), rgba(45, 149, 210, 0.92));
      color: #fff;
      box-shadow: 0 10px 24px rgba(26, 94, 176, 0.16);
    }

    .button.secondary {
      background: rgba(255, 255, 255, 0.84);
      border-color: rgba(29, 83, 140, 0.14);
      color: var(--blue-4);
    }

    .footer {
      padding: 40px 0 54px;
      color: var(--ink-soft);
      font-size: 0.92rem;
    }

    .footer-inner {
      border-top: 1px solid var(--line-strong);
      padding-top: 18px;
      display: flex;
      justify-content: space-between;
      gap: 18px;
      flex-wrap: wrap;
    }

    @media (max-width: 920px) {

      .hero-card {
        grid-template-columns: 1fr;
        padding: 28px;
      }

      .atlas-grid {
        grid-template-columns: 1fr;
      }

      h1 {
        max-width: none;
      }

      .hero-side {
        justify-items: center;
        text-align: center;
      }
    }

    @media (max-width: 680px) {
      .shell {
        width: min(calc(100% - 24px), var(--max));
      }

      .site-header .shell {
        align-items: center;
        gap: 12px;
      }

      .menu-toggle {
        display: inline-flex;
        margin-left: auto;
      }

      .header-actions {
        width: 100%;
        display: none;
        flex-direction: column;
        align-items: flex-start;
        gap: 14px;
        padding: 14px 0 4px;
      }

      body.menu-open .header-actions {
        display: flex;
      }

      .language-switcher {
        width: 100%;
        justify-content: space-between;
      }

      .site-nav {
        width: 100%;
        flex-direction: column;
        align-items: stretch;
        gap: 8px;
      }

      .site-nav a {
        width: 100%;
        padding: 10px 0;
        border-bottom: 1px solid rgba(29, 83, 140, 0.08);
      }

      .samples-grid {
        grid-template-columns: 1fr;
      }

      .section-card,
      .sample-card {
        padding: 22px;
      }



      .sample-card::before {
        margin-left: -22px;
        margin-right: -22px;
      }

      .contact-links {
        flex-direction: column;
        align-items: stretch;
      }
    }