:root {
      color-scheme: light;
      --bg: #f7f8fb;
      --bg-soft: #fcfcfd;
      --bg-panel: rgba(255, 255, 255, 0.9);
      --bg-panel-strong: #ffffff;
      --ink: #213246;
      --ink-soft: #5a6675;
      --navy: #23364d;
      --navy-soft: rgba(35, 54, 77, 0.1);
      --gold: #c3a35a;
      --gold-soft: rgba(195, 163, 90, 0.16);
      --mist: #e9edf3;
      --line: rgba(35, 54, 77, 0.12);
      --line-strong: rgba(35, 54, 77, 0.2);
      --shadow: 0 18px 44px rgba(30, 44, 63, 0.07);
      --shadow-soft: 0 10px 24px rgba(30, 44, 63, 0.045);
      --radius-xl: 22px;
      --radius-lg: 16px;
      --radius-md: 12px;
      --shell: min(1180px, calc(100% - 32px));
      --font-sans: "Zen Kaku Gothic New", "Hiragino Sans", "Yu Gothic", sans-serif;
      --font-serif: "Shippori Mincho", "Yu Mincho", serif;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      min-width: 320px;
      color: var(--ink);
      background:
        radial-gradient(circle at top left, rgba(35, 54, 77, 0.08), transparent 28%),
        radial-gradient(circle at 100% 0, rgba(195, 163, 90, 0.12), transparent 24%),
        linear-gradient(180deg, #ffffff 0%, #f8f9fb 42%, #f4f6f9 100%);
      font-family: var(--font-sans);
      line-height: 1.82;
      letter-spacing: 0.01em;
      overflow-x: hidden;
    }

    body::before {
      position: fixed;
      inset: 0;
      background:
        linear-gradient(90deg, rgba(35, 54, 77, 0.02) 1px, transparent 1px),
        linear-gradient(180deg, rgba(35, 54, 77, 0.018) 1px, transparent 1px);
      background-size: 40px 40px;
      mask: linear-gradient(180deg, transparent, rgba(0, 0, 0, 0.55) 14%, rgba(0, 0, 0, 0.55) 88%, transparent);
      content: "";
      pointer-events: none;
      z-index: -1;
    }

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

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

    button,
    input,
    textarea,
    select {
      font: inherit;
    }

    h1,
    h2,
    h3,
    h4,
    p,
    ul,
    li,
    figure,
    blockquote,
    dl,
    dd {
      margin: 0;
    }

    ul {
      padding-left: 1.2em;
    }

    .shell {
      width: var(--shell);
      margin: 0 auto;
    }

    .hero,
    .section {
      position: relative;
    }

    .hero {
      padding: clamp(38px, 6vw, 82px) 0 92px;
    }

    .hero::before,
    .hero::after {
      position: absolute;
      border-radius: 50%;
      content: "";
      filter: blur(18px);
      pointer-events: none;
      z-index: -1;
    }

    .hero::before {
      top: 30px;
      left: min(4vw, 40px);
      width: 180px;
      height: 180px;
      background: rgba(35, 54, 77, 0.08);
    }

    .hero::after {
      right: min(4vw, 40px);
      bottom: 34px;
      width: 220px;
      height: 220px;
      background: rgba(195, 163, 90, 0.12);
    }

    .hero__grid {
      display: grid;
      grid-template-columns: minmax(0, 1.08fr) minmax(320px, 0.92fr);
      gap: clamp(30px, 5vw, 58px);
      align-items: start;
    }

    .eyebrow,
    .section-label,
    .mini-label,
    .source-label {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      color: var(--gold);
      font-size: 0.75rem;
      font-weight: 700;
      letter-spacing: 0.15em;
      text-transform: uppercase;
    }

    .eyebrow {
      margin-bottom: 18px;
      padding: 8px 14px;
      border: 1px solid rgba(195, 163, 90, 0.22);
      border-radius: 999px;
      background: rgba(255, 255, 255, 0.84);
      color: var(--navy);
    }

    .eyebrow::before,
    .section-label::before,
    .source-label::before {
      width: 9px;
      height: 9px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--gold), rgba(35, 54, 77, 0.85));
      content: "";
    }

    .section-label {
      margin-bottom: 12px;
    }

    h1,
    h2,
    h3,
    h4 {
      font-family: var(--font-serif);
      line-height: 1.2;
      letter-spacing: 0.02em;
    }

    .hero h1 {
      font-size: clamp(2.4rem, 4.8vw, 4.1rem);
      line-height: 1.12;
      white-space: nowrap;
    }

    .hero__lead {
      max-width: 28ch;
      margin-top: 18px;
      color: var(--navy);
      font-size: clamp(1.1rem, 2vw, 1.4rem);
      line-height: 1.95;
      text-wrap: balance;
    }

    .hero__body {
      max-width: 60ch;
      margin-top: 22px;
      color: var(--ink-soft);
      font-size: 1rem;
    }

    .hero__meta {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 24px;
    }

    .meta-pill {
      padding: 10px 14px;
      border: 1px solid var(--line);
      border-radius: 14px;
      background: rgba(255, 255, 255, 0.82);
      color: var(--navy);
      font-size: 0.88rem;
      font-weight: 700;
    }

    .panel,
    .hero-map,
    .quote-panel,
    .cta-strip,
    .compare-card,
    .address-card,
    .mini-card,
    .standard-card,
    .takeaway-card,
    .source-card,
    .doc-card {
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      background: var(--bg-panel);
      box-shadow: var(--shadow);
      backdrop-filter: blur(10px);
    }

    .hero-map {
      position: relative;
      padding: clamp(22px, 3vw, 28px);
      overflow: hidden;
      isolation: isolate;
      min-height: 540px;
      background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(245, 247, 250, 0.92)),
        radial-gradient(circle at top right, rgba(195, 163, 90, 0.12), transparent 42%);
    }

    .hero-map::before {
      position: absolute;
      inset: 18px;
      border: 1px solid rgba(35, 54, 77, 0.08);
      border-radius: 18px;
      content: "";
      pointer-events: none;
    }

    .world-map {
      width: 100%;
      min-height: 360px;
    }

    .hero-map__note {
      display: grid;
      gap: 10px;
      margin-top: 12px;
      padding: 18px;
      border: 1px solid rgba(35, 54, 77, 0.1);
      border-radius: var(--radius-lg);
      background: rgba(255, 255, 255, 0.9);
    }

    .hero-map__note strong,
    .quote-panel strong,
    .address-card strong,
    .standard-card strong,
    .takeaway-card strong {
      color: var(--navy);
    }

    .hero-map__note p,
    .address-card p,
    .mini-card p,
    .compare-card p,
    .standard-card p,
    .takeaway-card p,
    .doc-card p,
    .source-card p {
      color: var(--ink-soft);
    }

    .hero-map__verified {
      margin-top: 10px;
      color: var(--ink-soft);
      font-size: 0.88rem;
    }

    .section {
      padding: 0 0 88px;
      scroll-margin-top: 92px;
    }

    .section-head {
      max-width: 920px;
      margin-bottom: 30px;
    }

    .section-head h2 {
      font-size: clamp(1.9rem, 3vw, 2.65rem);
      line-height: 1.18;
      white-space: nowrap;
    }

    .section-head p {
      margin-top: 14px;
      color: var(--ink-soft);
      font-size: 1rem;
    }

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

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 18px;
    }

    .address-stack,
    .source-stack,
    .doc-grid,
    .takeaway-grid {
      display: grid;
      gap: 18px;
    }

    .address-card,
    .mini-card,
    .compare-card,
    .standard-card,
    .takeaway-card,
    .doc-card,
    .source-card,
    .quote-panel {
      padding: clamp(18px, 3vw, 24px);
    }

    .address-card h3,
    .mini-card h3,
    .compare-card h3,
    .standard-card h3,
    .takeaway-card h3,
    .doc-card h3 {
      font-size: 1.28rem;
      line-height: 1.2;
      white-space: nowrap;
    }

    .address-lines {
      margin-top: 16px;
      padding: 16px 18px;
      border: 1px solid rgba(35, 54, 77, 0.08);
      border-radius: var(--radius-md);
      background: rgba(245, 248, 251, 0.9);
      color: var(--navy);
      font-size: 0.98rem;
      line-height: 1.9;
    }

    .address-meta {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 18px;
    }

    .address-chip {
      padding: 8px 12px;
      border-radius: 12px;
      border: 1px solid rgba(35, 54, 77, 0.12);
      background: #fff;
      color: var(--navy);
      font-size: 0.86rem;
      font-weight: 700;
    }

    .location-diagram {
      width: 100%;
      min-height: 220px;
    }

    .caution-note,
    .law-note {
      margin-top: 18px;
      padding: 16px 18px;
      border-radius: var(--radius-md);
      border: 1px dashed rgba(35, 54, 77, 0.22);
      background: rgba(255, 255, 255, 0.72);
      color: var(--ink-soft);
      font-size: 0.94rem;
    }

    .compare-card {
      display: grid;
      gap: 12px;
      min-height: 100%;
    }

    .compare-card ul {
      margin: 0;
      color: var(--ink-soft);
    }

    .bridge-note {
      margin-top: 20px;
      padding: 18px 22px;
      border-radius: var(--radius-lg);
      background: linear-gradient(135deg, rgba(35, 54, 77, 0.92), rgba(35, 54, 77, 0.78));
      color: #f7f8fb;
      text-align: center;
      box-shadow: var(--shadow);
    }

    .bridge-note strong {
      color: #fff;
    }

    .system-panel {
      display: grid;
      gap: 18px;
      padding: clamp(18px, 3vw, 24px);
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      background: rgba(255, 255, 255, 0.84);
      box-shadow: var(--shadow-soft);
    }

    .logic-rail {
      display: grid;
      grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr);
      gap: 14px;
      align-items: center;
    }

    .logic-node {
      padding: 22px 20px;
      border: 1px solid rgba(35, 54, 77, 0.12);
      border-radius: var(--radius-lg);
      background: rgba(255, 255, 255, 0.92);
    }

    .logic-node strong {
      display: block;
      color: var(--navy);
      font-family: var(--font-serif);
      font-size: clamp(1.5rem, 2vw, 2rem);
      line-height: 1.12;
    }

    .logic-node span {
      display: block;
      margin-top: 10px;
      color: var(--ink-soft);
      font-size: 0.94rem;
      line-height: 1.7;
    }

    .logic-arrow {
      color: rgba(35, 54, 77, 0.68);
      font-size: 1.35rem;
      font-weight: 500;
      line-height: 1;
      text-align: center;
    }

    .standard-card {
      display: grid;
      gap: 10px;
      min-height: 100%;
    }

    .standard-card__kicker {
      color: var(--gold);
      font-size: 0.74rem;
      font-weight: 700;
      letter-spacing: 0.16em;
      text-transform: uppercase;
    }

    .standard-card h3 {
      margin-top: 2px;
    }

    .oil-layout {
      display: grid;
      grid-template-columns: minmax(0, 0.92fr) minmax(320px, 1.08fr);
      gap: 24px;
      align-items: start;
    }

    .oil-figure {
      display: grid;
      gap: 18px;
      padding: clamp(18px, 3vw, 24px);
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      background: rgba(255, 255, 255, 0.88);
      box-shadow: var(--shadow);
    }

    .oil-diagram {
      width: 100%;
      min-height: 340px;
    }

    .component-list {
      display: grid;
      gap: 0;
      margin-top: 20px;
    }

    .component-row {
      display: grid;
      grid-template-columns: 120px minmax(0, 1fr);
      gap: 16px;
      align-items: baseline;
      padding: 10px 0;
      border-top: 1px solid rgba(35, 54, 77, 0.1);
    }

    .component-row:first-child {
      border-top: none;
      padding-top: 0;
    }

    .component-row__label {
      color: var(--ink-soft);
      font-size: 0.72rem;
      font-weight: 700;
      letter-spacing: 0.16em;
      text-transform: uppercase;
    }

    .component-row strong {
      color: var(--navy);
      font-family: var(--font-serif);
      font-size: 1.05rem;
      line-height: 1.4;
    }

    .step-rail {
      display: grid;
      grid-template-columns: repeat(4, minmax(0, 1fr));
      gap: 16px;
      margin-top: 22px;
    }

    .step-card {
      position: relative;
      padding: 20px 18px;
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      background: rgba(255, 255, 255, 0.9);
      box-shadow: var(--shadow-soft);
    }

    .step-card::after {
      position: absolute;
      top: 50%;
      right: -10px;
      width: 20px;
      height: 2px;
      background: linear-gradient(90deg, rgba(35, 54, 77, 0.28), rgba(195, 163, 90, 0.65));
      content: "";
      transform: translateY(-50%);
    }

    .step-card:last-child::after {
      display: none;
    }

    .step-number {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-width: 34px;
      height: 30px;
      padding: 0 10px;
      border-radius: 10px;
      border: 1px solid rgba(35, 54, 77, 0.12);
      background: rgba(255, 255, 255, 0.92);
      color: var(--navy);
      font-size: 0.84rem;
      font-weight: 700;
    }

    .step-card h3 {
      margin-top: 14px;
      font-size: 1.18rem;
    }

    .step-card p {
      margin-top: 10px;
      color: var(--ink-soft);
      font-size: 0.95rem;
    }

    .doc-grid {
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .doc-card {
      display: grid;
      gap: 12px;
      min-height: 100%;
    }

    .doc-card__icon {
      width: 46px;
      height: 54px;
      border-radius: 10px;
      display: inline-grid;
      place-items: center;
      border: 1px solid rgba(35, 54, 77, 0.12);
      background: rgba(255, 255, 255, 0.7);
    }

    .doc-card ul {
      margin: 0;
      color: var(--ink-soft);
    }

    .cta-strip {
      display: flex;
      gap: 22px;
      align-items: center;
      justify-content: space-between;
      margin-top: 24px;
      padding: clamp(22px, 3vw, 30px);
    }

    .cta-strip h3 {
      font-size: clamp(1.5rem, 2.2vw, 2rem);
    }

    .cta-strip p {
      margin-top: 10px;
      max-width: 60ch;
      color: var(--ink-soft);
    }

    .cta-strip__actions {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      align-items: center;
    }

    .button {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-height: 48px;
      padding: 0 20px;
      border-radius: 14px;
      border: 1px solid var(--navy);
      color: var(--navy);
      font-weight: 700;
      transition: transform 180ms ease, box-shadow 180ms ease, background-color 180ms ease;
    }

    .button:hover,
    .button:focus-visible {
      transform: translateY(-1px);
      box-shadow: var(--shadow-soft);
      outline: none;
    }

    .button--primary {
      background: linear-gradient(135deg, rgba(35, 54, 77, 0.96), rgba(35, 54, 77, 0.88));
      border-color: transparent;
      color: #ffffff;
    }

    .button--ghost {
      background: rgba(255, 255, 255, 0.72);
    }

    .quote-panel {
      position: relative;
      overflow: hidden;
      background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(246, 248, 251, 0.92)),
        radial-gradient(circle at top right, rgba(195, 163, 90, 0.12), transparent 42%);
    }

    .quote-panel::after {
      position: absolute;
      top: -18px;
      right: 18px;
      color: rgba(35, 54, 77, 0.08);
      font-family: var(--font-serif);
      font-size: 8rem;
      content: "“";
    }

    .quote-panel blockquote {
      margin-top: 22px;
      color: var(--navy);
      font-family: var(--font-serif);
      font-size: clamp(1.5rem, 2.8vw, 2.3rem);
      line-height: 1.55;
    }

    .takeaway-grid {
      grid-template-columns: repeat(3, minmax(0, 1fr));
      margin-top: 24px;
    }

    .takeaway-card {
      min-height: 100%;
    }

    .takeaway-card h3 {
      font-size: 1.18rem;
    }

    .source-stack {
      grid-template-columns: repeat(2, minmax(0, 1fr));
      margin-top: 26px;
    }

    .source-card {
      display: grid;
      gap: 12px;
      min-height: 100%;
    }

    .source-card ul {
      margin: 0;
      color: var(--ink-soft);
    }

    .source-card a {
      color: var(--navy);
      text-decoration: underline;
      text-underline-offset: 0.16em;
    }

    .inline-source {
      margin-top: 18px;
      color: var(--ink-soft);
      font-size: 0.9rem;
    }

    .footer {
      padding: 0 0 64px;
    }

    .footer-card {
      padding: 18px 20px;
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      background: rgba(255, 255, 255, 0.86);
      color: var(--ink-soft);
      font-size: 0.9rem;
      box-shadow: var(--shadow-soft);
    }

    .footer-card strong {
      color: var(--navy);
    }

    @media (max-width: 1100px) {
      .hero__grid,
      .grid-2,
      .oil-layout,
      .doc-grid,
      .takeaway-grid,
      .source-stack {
        grid-template-columns: 1fr;
      }

      .grid-3,
      .step-rail {
        grid-template-columns: 1fr 1fr;
      }

      .logic-rail {
        grid-template-columns: 1fr;
      }

      .logic-arrow {
        transform: rotate(90deg);
      }

      .cta-strip {
        flex-direction: column;
        align-items: flex-start;
      }
    }

    @media (max-width: 760px) {
      .hero {
        padding-top: 30px;
      }

      .hero h1 {
        white-space: normal;
        font-size: clamp(2.1rem, 9vw, 3rem);
      }

      .section-head h2,
      .address-card h3,
      .mini-card h3,
      .compare-card h3,
      .standard-card h3,
      .doc-card h3,
      .cta-strip h3 {
        white-space: normal;
      }

      .hero-map {
        min-height: 0;
      }

      .grid-3,
      .step-rail {
        grid-template-columns: 1fr;
      }

      .step-card::after {
        top: auto;
        right: auto;
        bottom: -10px;
        left: 50%;
        width: 2px;
        height: 20px;
        transform: translateX(-50%);
      }

      .step-card:last-child::after {
        display: none;
      }

      .quote-panel::after {
        font-size: 5rem;
      }

      .component-row {
        grid-template-columns: 1fr;
        gap: 4px;
      }
    }

    @media (max-width: 540px) {
      .hero h1 {
        font-size: clamp(2.35rem, 11vw, 3.2rem);
      }

      .hero__lead {
        max-width: none;
      }

      .address-card,
      .mini-card,
      .compare-card,
      .standard-card,
      .takeaway-card,
      .doc-card,
      .source-card,
      .quote-panel,
      .hero-map,
      .cta-strip,
      .system-panel {
        padding: 16px;
      }

      .button {
        width: 100%;
      }

      .cta-strip__actions {
        width: 100%;
      }
    }