:root {
      --ink: #06131f;
      --paper: #ffffff;
      --line: #dbe3ea;
      --muted: #4b5563;
      --signal: #0b63ce;
      --font-sans: HelveticaNeue, "Helvetica Neue", Helvetica, Arial,
        "游ゴシック体", YuGothic, "游ゴシック Medium", "Yu Gothic Medium",
        "游ゴシック", "Yu Gothic", "ヒラギノ角ゴ ProN W3", "Hiragino Kaku Gothic ProN",
        "ヒラギノ角ゴ Pro W3", "Hiragino Kaku Gothic Pro", "MS ゴシック", "MS Gothic",
        sans-serif;
      --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
      font-family: var(--font-sans);
      color: var(--ink);
      background: var(--paper);
    }

    * { box-sizing: border-box; }

    html { scroll-behavior: smooth; }

    body {
      margin: 0;
      font-size: 16px;
      line-height: 1.8;
      font-feature-settings: "palt";
      -webkit-font-smoothing: antialiased;
      word-wrap: break-word;
      background: #f8f7f2;
    }

    a { color: inherit; text-decoration: none; }
    img { display: block; max-width: 100%; height: auto; }

    .site-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 18px;
      min-height: 62px;
      padding: 14px clamp(20px, 4vw, 58px) 10px;
      background: #f8f7f2;
      box-shadow: inset 0 -1px 0 rgba(6, 19, 31, 0.08);
    }

    .brand {
      display: inline-flex;
      align-items: center;
      gap: 7px;
    }

    .brand-symbol { width: 40px; }
    .brand-wordmark { width: 96px; }

    .back-link {
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 780;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    .back-link:hover,
    .back-link:focus-visible {
      color: var(--signal);
      outline: none;
    }

    main {
      max-width: 760px;
      margin: 0 auto;
      padding: clamp(40px, 7vw, 88px) clamp(20px, 4vw, 40px) clamp(60px, 9vw, 120px);
    }

    .section-label {
      color: var(--signal);
      font-family: var(--font-mono);
      font-size: 12px;
      font-weight: 780;
      letter-spacing: 0.1em;
      text-transform: uppercase;
    }

    .breadcrumb {
      margin-bottom: 18px;
      color: var(--muted);
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 780;
      letter-spacing: 0.06em;
    }

    .breadcrumb a {
      text-decoration: underline;
      text-underline-offset: 3px;
    }

    .breadcrumb a:hover,
    .breadcrumb a:focus-visible {
      color: var(--signal);
      outline: none;
    }

    .page-meta {
      margin: 0 0 28px;
      color: var(--muted);
      font-family: var(--font-mono);
      font-size: 12px;
      letter-spacing: 0.04em;
    }

    h1 {
      margin: 14px 0 10px;
      font-size: clamp(28px, 4vw, 40px);
      font-weight: 820;
      line-height: 1.2;
      letter-spacing: 0.02em;
    }

    .glossary-lead {
      margin: 0 0 36px;
      color: var(--ink);
    }

    .toc {
      margin: 0 0 44px;
      padding: 20px 24px;
      border: 1px solid var(--ink);
      background: var(--paper);
    }

    .toc b {
      display: block;
      margin-bottom: 10px;
      color: var(--signal);
      font-family: var(--font-mono);
      font-size: 12px;
      font-weight: 780;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    .toc ol {
      margin: 0;
      padding-left: 1.4em;
    }

    .toc li { margin-bottom: 4px; }

    section {
      margin-bottom: 34px;
      padding-top: 22px;
      border-top: 1px solid var(--ink);
    }

    h2 {
      margin: 0 0 12px;
      font-size: clamp(20px, 2.4vw, 24px);
      font-weight: 820;
      letter-spacing: 0.02em;
      line-height: 1.4;
    }

    h3 {
      margin: 24px 0 8px;
      font-size: 17px;
      font-weight: 820;
      letter-spacing: 0.02em;
      line-height: 1.5;
    }

    p, ul { margin: 0 0 12px; color: var(--ink); }
    ul { padding-left: 1.4em; }
    li { margin-bottom: 4px; }

    .explosion-figure {
      margin: 20px 0 18px;
      padding: 22px;
      border: 1px solid var(--ink);
      background: var(--paper);
    }

    .explosion-figure figcaption {
      margin-bottom: 16px;
      color: var(--signal);
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 780;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    .explosion-flow {
      display: flex;
      flex-direction: column;
    }

    .explosion-duo {
      display: grid;
      grid-template-columns: minmax(0, 1fr) 28px minmax(0, 1fr);
      align-items: stretch;
      gap: 10px;
    }

    .explosion-duo .explosion-step {
      grid-template-columns: 34px minmax(0, 1fr);
      gap: 10px;
      padding: 13px;
    }

    .explosion-duo .explosion-number {
      width: 34px;
      height: 34px;
    }

    .explosion-duo-link {
      display: grid;
      place-items: center;
      color: var(--signal);
      font-size: 18px;
      font-weight: 820;
    }

    .explosion-step {
      display: grid;
      grid-template-columns: 38px minmax(0, 1fr);
      align-items: start;
      gap: 14px;
      padding: 14px 16px;
      border: 1px solid var(--ink);
      background: var(--paper);
    }

    .explosion-step.is-origin {
      color: #fff;
      background: var(--ink);
    }

    .explosion-number {
      display: grid;
      width: 38px;
      height: 38px;
      place-items: center;
      border: 1px solid currentColor;
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 780;
    }

    .explosion-step.is-origin .explosion-number {
      border-color: rgba(255, 255, 255, 0.65);
      font-size: 16px;
    }

    .explosion-copy { min-width: 0; }

    .explosion-title {
      margin: 0;
      color: inherit;
      font-size: 15px;
      font-weight: 820;
      line-height: 1.5;
    }

    .explosion-title small {
      margin-left: 8px;
      color: var(--signal);
      font-family: var(--font-mono);
      font-size: 10px;
      font-weight: 780;
      letter-spacing: 0.06em;
      text-transform: uppercase;
    }

    .explosion-step.is-origin .explosion-title small { color: #9cc4f5; }

    .explosion-description {
      margin: 1px 0 0;
      color: var(--muted);
      font-size: 12.5px;
      line-height: 1.7;
    }

    .explosion-step.is-origin .explosion-description {
      color: rgba(255, 255, 255, 0.76);
    }

    .explosion-arrow {
      align-self: center;
      display: grid;
      height: 24px;
      place-items: center;
      color: var(--signal);
      font-size: 15px;
      line-height: 1;
    }

    .explosion-conditions {
      display: grid;
      grid-template-columns: max-content minmax(0, 1fr);
      gap: 8px 14px;
      margin: 16px 0 0;
      padding: 12px 14px;
      border: 1px dashed var(--muted);
      color: var(--muted);
      font-size: 12px;
      line-height: 1.7;
    }

    .explosion-conditions b {
      color: var(--ink);
      font-family: var(--font-mono);
      font-size: 10px;
      font-weight: 780;
      letter-spacing: 0.06em;
      text-transform: uppercase;
    }

    .alignment-figure,
    .future-visions {
      margin: 20px 0 18px;
      border: 1px solid var(--ink);
      background: var(--paper);
    }

    .alignment-figure img {
      width: 100%;
      aspect-ratio: 3 / 2;
      object-fit: cover;
    }

    .alignment-figure figcaption,
    .future-visions figcaption {
      padding: 11px 14px 12px;
      border-top: 1px solid var(--ink);
      color: var(--muted);
      font-size: 12px;
      line-height: 1.65;
    }

    .alignment-position {
      margin: 20px 0 18px;
      padding: 22px;
      border: 1px solid var(--ink);
      background: var(--paper);
    }

    .alignment-position-label {
      margin-bottom: 8px;
      color: var(--signal);
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 780;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    .alignment-position h3 {
      margin: 0 0 10px;
      font-size: clamp(19px, 2.5vw, 23px);
    }

    .alignment-principle {
      margin: 16px 0 0;
      padding-top: 14px;
      border-top: 1px solid var(--line);
      font-weight: 820;
    }

    .future-vision-grid {
      display: grid;
      grid-template-columns: minmax(0, 1.35fr) minmax(0, 0.65fr);
      height: 270px;
    }

    .future-vision {
      min-width: 0;
      overflow: hidden;
    }

    .future-vision + .future-vision {
      border-left: 1px solid var(--ink);
    }

    .future-vision img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 180ms ease;
    }

    .future-vision:hover img,
    .future-vision:focus-visible img {
      transform: scale(1.015);
    }

    .future-vision:focus-visible {
      outline: 3px solid var(--signal);
      outline-offset: -3px;
    }

    @media (max-width: 520px) {
      .explosion-figure { padding: 16px; }

      .explosion-step {
        grid-template-columns: 34px minmax(0, 1fr);
        gap: 11px;
        padding: 13px;
      }

      .explosion-number {
        width: 34px;
        height: 34px;
      }

      .explosion-title small {
        display: block;
        margin: 1px 0 0;
      }

      .explosion-duo {
        grid-template-columns: 1fr;
        gap: 0;
      }

      .explosion-duo-link {
        height: 24px;
        transform: rotate(90deg);
      }

      .explosion-conditions { grid-template-columns: 1fr; }

      .alignment-position { padding: 17px; }

      .future-vision-grid {
        grid-template-columns: 1fr 1fr;
        height: 170px;
      }
    }

    .related {
      margin-top: 16px;
      padding: 14px 18px;
      border-left: 3px solid var(--signal);
      background: var(--paper);
      font-size: 14px;
    }

    .related b {
      display: block;
      margin-bottom: 6px;
      color: var(--signal);
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 780;
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }

    main a {
      color: var(--ink);
      text-decoration: underline;
      text-underline-offset: 3px;
    }

    main a:hover,
    main a:focus-visible {
      color: var(--signal);
      outline: none;
    }

    .glossary-cta {
      margin-top: 48px;
      padding: 24px;
      border: 1px solid var(--ink);
      background: var(--paper);
    }

    .glossary-cta p { margin: 0; }

    .site-footer {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-between;
      gap: 10px 16px;
      padding: 18px clamp(20px, 4vw, 58px);
      background: linear-gradient(180deg, #eef2f5 0%, #f8f7f2 62%);
      box-shadow: inset 0 1px 0 rgba(6, 19, 31, 0.08);
      color: var(--muted);
      font-family: var(--font-mono);
      font-size: 11px;
      font-weight: 850;
      letter-spacing: 0.04em;
      text-transform: uppercase;
    }

    .site-footer a:hover,
    .site-footer a:focus-visible {
      color: var(--signal);
      outline: none;
    }