:root {
        --bg: #ffffff;
        --text: #111111;
        --muted: #666666;
        --card: #ffffff;
        --border: #e6e6e6;
        --link: #111111;
        --btn-bg: #111111;
        --btn-text: #ffffff;
        --btn-brd: #111111;
        --shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
        --quote-bar: #b9c0cb;
        --quote-bg: #f4f6f8;
        --quote-text: #111111;
        --quote-strong: #0b0d10;
        --reader-font-scale: 1;
        --reader-line-height: 1.75;
        --reader-max-width: 800px;
        --reader-font-family: "Georgia", "Times New Roman", serif;
        color-scheme: light dark;
      }

      @media (prefers-color-scheme: dark) {
        :root {
          --bg: #0b0e13;
          --text: #e7eaf0;
          --muted: #a8b2c1;
          --card: #11151d;
          --border: #253043;
          --link: #e7eaf0;
          --btn-bg: #e7eaf0;
          --btn-text: #0b0e13;
          --btn-brd: #e7eaf0;
          --shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
          --quote-bar: #5a6474;
          --quote-bg: #0f141c;
          --quote-text: #eef2f8;
          --quote-strong: #ffffff;
        }
      }

      :root[data-theme="light"] {
        --bg: #ffffff;
        --text: #111111;
        --muted: #666666;
        --card: #ffffff;
        --border: #e6e6e6;
        --link: #111111;
        --btn-bg: #111111;
        --btn-text: #ffffff;
        --btn-brd: #111111;
        --shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
        --quote-bar: #b9c0cb;
        --quote-bg: #f4f6f8;
        --quote-text: #111111;
        --quote-strong: #0b0d10;
      }

      :root[data-theme="dark"] {
        --bg: #0b0e13;
        --text: #e7eaf0;
        --muted: #a8b2c1;
        --card: #11151d;
        --border: #253043;
        --link: #e7eaf0;
        --btn-bg: #e7eaf0;
        --btn-text: #0b0e13;
        --btn-brd: #e7eaf0;
        --shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
        --quote-bar: #5a6474;
        --quote-bg: #0f141c;
        --quote-text: #eef2f8;
        --quote-strong: #ffffff;
      }

      * {
        box-sizing: border-box;
      }

      body {
        margin: 0;
        font-family: "Georgia", "Times New Roman", serif;
        background: var(--bg);
        color: var(--text);
        transition: background 0.2s ease, color 0.2s ease;
      }

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

      a:hover {
        text-decoration: underline;
      }

      .site-header {
        position: sticky;
        top: 0;
        z-index: 30;
        background: color-mix(in oklab, var(--bg), var(--card) 40%);
        border-bottom: 1px solid var(--border);
        backdrop-filter: blur(8px);
        padding: 0.85rem 1.25rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
      }

      .read-progress {
        position: absolute;
        left: 0;
        right: 0;
        bottom: -1px;
        height: 3px;
        background: color-mix(in oklab, var(--border), transparent 45%);
        overflow: hidden;
      }

      .read-progress-fill {
        height: 100%;
        width: 100%;
        transform-origin: left center;
        transform: scaleX(0);
        background: var(--btn-bg);
        transition: transform 0.08s linear;
      }

      .header-content {
        max-width: 800px;
        margin: 0 auto;
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 1rem;
        flex-wrap: wrap;
      }

      .brand {
        font-weight: 600;
        font-size: 1.05rem;
        font-family: "Merriweather", serif;
      }

      .header-right {
        display: flex;
        align-items: center;
        gap: 1rem;
      }

      .reader-controls {
        display: flex;
        align-items: center;
        gap: 0.45rem;
      }

      .crumbs {
        display: flex;
        align-items: center;
        gap: 0.35rem;
        font-size: 0.9rem;
        color: var(--muted);
      }

      .crumbs a {
        color: var(--muted);
      }

      .crumbs a:hover {
        color: var(--text);
      }

      .theme-toggle {
        border: 1px solid var(--border);
        background: var(--card);
        color: var(--text);
        border-radius: 8px;
        padding: 0.4rem 0.5rem;
        cursor: pointer;
        font-size: 0.9rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
      }

      .theme-toggle:hover {
        filter: brightness(1.05);
      }

      .theme-toggle:focus-visible {
        outline: 2px solid color-mix(in oklab, var(--btn-brd), transparent 35%);
        outline-offset: 2px;
      }

      .reader-settings-toggle {
        font-weight: 600;
        letter-spacing: 0.01em;
      }

      .reader-settings {
        position: fixed;
        top: 4.3rem;
        right: 1rem;
        z-index: 40;
        width: min(320px, calc(100vw - 1rem));
        padding: 0.8rem;
        border: 1px solid var(--border);
        border-radius: 12px;
        background: var(--card);
        box-shadow: 0 18px 46px rgba(0, 0, 0, 0.24);
      }

      .reader-settings[hidden] {
        display: none;
      }

      .reader-settings-title {
        margin: 0 0 0.5rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.92rem;
        font-weight: 700;
      }

      .reader-settings-grid {
        display: grid;
        gap: 0.55rem;
      }

      .reader-setting {
        display: grid;
        gap: 0.32rem;
      }

      .reader-setting label {
        display: flex;
        justify-content: space-between;
        gap: 0.5rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.8rem;
      }

      .reader-setting label strong {
        font-weight: 600;
      }

      .reader-setting-value {
        color: var(--muted);
      }

      .reader-setting input[type="range"] {
        width: 100%;
      }

      .reader-setting select {
        width: 100%;
        border: 1px solid var(--border);
        border-radius: 8px;
        background: var(--card);
        color: var(--text);
        padding: 0.5rem 0.55rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.85rem;
      }

      .reader-setting-hint {
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.74rem;
        color: var(--muted);
      }

      .reader-setting-width input[type="range"]:disabled {
        opacity: 0.5;
        cursor: not-allowed;
      }

      .reader-settings-actions {
        margin-top: 0.2rem;
        display: flex;
        justify-content: flex-end;
      }

      .reader-settings-reset {
        border: 1px solid var(--border);
        background: var(--card);
        color: var(--text);
        border-radius: 8px;
        padding: 0.42rem 0.6rem;
        cursor: pointer;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.8rem;
      }

      .reader-settings-reset:hover {
        background: color-mix(in oklab, var(--card), var(--text) 6%);
      }

      .reader-settings-reset:focus-visible {
        outline: 2px solid color-mix(in oklab, var(--btn-brd), transparent 35%);
        outline-offset: 2px;
      }

      .reader {
        max-width: var(--reader-max-width);
        margin: 0 auto;
        padding: 2rem 1.25rem 4rem;
      }

      article {
        font-family: var(--reader-font-family);
        font-size: clamp(
          calc(1.05rem * var(--reader-font-scale)),
          calc(2.2vw * var(--reader-font-scale)),
          calc(1.15rem * var(--reader-font-scale))
        );
        line-height: var(--reader-line-height);
      }

      article h1 {
        font-family: var(--reader-font-family);
        font-size: clamp(1.8rem, 4vw, 2.4rem);
        line-height: 1.2;
        margin: 0 0 0.5rem;
        font-weight: 600;
      }

      .chapter-meta {
        color: var(--muted);
        font-size: 0.95rem;
        margin-bottom: 2rem;
        font-family: system-ui, -apple-system, sans-serif;
      }

      .chapter-audio {
        margin: 0 0 1.6rem;
        padding: 0.9rem 1rem;
        border: 1px solid color-mix(in oklab, var(--border), transparent 12%);
        border-radius: 14px;
        background: color-mix(in oklab, var(--card), var(--bg) 16%);
        box-shadow: var(--shadow);
      }

      .chapter-audio-copy {
        display: grid;
        gap: 0.18rem;
        margin-bottom: 0.75rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
      }

      .chapter-audio-label {
        color: var(--muted);
        font-size: 0.78rem;
        text-transform: uppercase;
        letter-spacing: 0.08em;
      }

      .chapter-audio-copy strong {
        font-size: 0.98rem;
        line-height: 1.3;
      }

      .chapter-audio audio {
        width: 100%;
      }

      .chapter-audio-player {
        width: 100%;
      }

      .chapter-audio-link {
        display: inline-flex;
        align-items: center;
        gap: 0.35rem;
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.92rem;
      }

      .chapter-audio-embed {
        display: block;
        width: 100%;
        border: 0;
        border-radius: 12px;
        overflow: hidden;
        background: transparent;
      }

      .chapter-audio-embed.youtube {
        aspect-ratio: 16 / 9;
        min-height: 240px;
      }

      .chapter-audio-embed.soundcloud {
        min-height: 166px;
      }

      .chapter-audio-embed.spotify {
        min-height: 152px;
      }

      article p {
        margin: 0 0 1.25rem;
      }

      article p.journal-box {
        margin: 1.3rem 0 1.45rem;
        padding: 0.7rem 0.85rem;
        white-space: pre;
        overflow-x: auto;
        line-height: 1.22;
        font-size: 0.95rem;
        letter-spacing: 0;
        word-spacing: 0;
        tab-size: 2;
        font-kerning: none;
        font-variant-ligatures: none;
        font-feature-settings: "liga" 0, "calt" 0;
        font-family: "Cascadia Mono", "Consolas", "Courier New", "MS Gothic", monospace;
        color: var(--text);
        background: color-mix(in oklab, var(--card), var(--bg) 25%);
        border: 1px solid color-mix(in oklab, var(--border), transparent 15%);
        border-radius: 10px;
      }

      article p.journal-box em,
      article p.journal-box strong,
      article p.journal-box code {
        font-family: inherit;
      }

      article hr {
        border: 0;
        border-top: 1px solid color-mix(in oklab, var(--border), transparent 35%);
        width: min(34ch, 58%);
        margin: 2rem auto;
        opacity: 0.75;
      }

      article blockquote {
        margin: 1.1rem 0 1.35rem;
        padding: 0.35rem 0 0.35rem 0.95rem;
        border-left: 4px solid var(--quote-bar);
        color: var(--quote-text);
        background: var(--quote-bg);
        border-radius: 0 8px 8px 0;
      }

      article blockquote p {
        margin: 0 0 0.7rem;
      }

      article blockquote strong {
        color: var(--quote-strong);
      }

      article blockquote p:last-child {
        margin-bottom: 0;
      }

      article h2,
      article h3 {
        line-height: 1.3;
        margin-top: 2rem;
        margin-bottom: 0.75rem;
      }

      .pager {
        display: grid;
        grid-template-columns: 1fr auto 1fr;
        gap: 0.75rem;
        margin-top: 2.25rem;
        padding: 0.85rem;
        border: 1px solid var(--border);
        border-radius: 12px;
        background: var(--card);
        box-shadow: var(--shadow);
        align-items: center;
      }

      .pager .btn {
        display: inline-block;
        padding: 0.75rem 1rem;
        border: 1px solid var(--border);
        border-radius: 8px;
        background: var(--card);
        color: var(--text);
        text-decoration: none;
        font-family: system-ui, -apple-system, sans-serif;
        font-size: 0.95rem;
        transition: all 0.2s ease;
      }

      .pager .btn:hover {
        background: var(--btn-bg);
        color: var(--btn-text);
        border-color: var(--btn-brd);
        text-decoration: none;
      }

      .pager .btn:focus-visible {
        outline: 2px solid color-mix(in oklab, var(--btn-brd), transparent 35%);
        outline-offset: 2px;
      }

      .pager .prev {
        justify-self: start;
      }

      .pager .next {
        justify-self: end;
      }

      .pager .toc {
        justify-self: center;
        font-weight: 600;
      }

      .pager .next {
        font-weight: 700;
        background: var(--btn-bg);
        color: var(--btn-text);
        border-color: var(--btn-brd);
      }

      .pager .next:hover {
        filter: brightness(1.06);
        text-decoration: none;
      }

      .pager .btn.disabled {
        opacity: 0.6;
        pointer-events: none;
      }

      .pager span:empty {
        visibility: hidden;
      }

      .chapter-complete {
        margin-top: 2rem;
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 0.8rem;
        padding: 0.8rem 0.9rem;
        border: 1px solid color-mix(in oklab, var(--btn-brd), var(--border) 50%);
        border-radius: 12px;
        background: color-mix(in oklab, var(--card), var(--btn-bg) 4%);
        box-shadow: var(--shadow);
      }

      .chapter-complete-copy {
        display: grid;
        gap: 0.12rem;
        min-width: 0;
      }

      .chapter-complete-copy strong {
        font-family: "Roboto", system-ui, -apple-system, Segoe UI, sans-serif;
        font-size: 0.95rem;
      }

      .chapter-complete-copy span {
        color: var(--muted);
        font-family: system-ui, -apple-system, sans-serif;
        font-size: 0.87rem;
      }

      .chapter-complete-actions {
        display: flex;
        flex-wrap: wrap;
        gap: 0.45rem;
        justify-content: flex-end;
      }

      .chapter-complete-actions .btn {
        display: inline-block;
        padding: 0.58rem 0.78rem;
        border: 1px solid var(--border);
        border-radius: 8px;
        text-decoration: none;
        color: var(--text);
        background: var(--card);
        font-family: system-ui, -apple-system, sans-serif;
        font-size: 0.84rem;
        line-height: 1.2;
      }

      .chapter-complete-actions .btn:hover {
        text-decoration: none;
        filter: brightness(1.04);
      }

      .chapter-complete-actions .btn:focus-visible {
        outline: 2px solid color-mix(in oklab, var(--btn-brd), transparent 35%);
        outline-offset: 2px;
      }

      .chapter-complete-actions .complete-next {
        border-color: var(--btn-brd);
        background: var(--btn-bg);
        color: var(--btn-text);
        font-weight: 700;
      }

      .mobile-chapter-nav {
        display: none;
        position: fixed;
        left: 0;
        right: 0;
        bottom: 0;
        z-index: 25;
        border-top: 1px solid var(--border);
        background: color-mix(in oklab, var(--bg), var(--card) 35%);
        backdrop-filter: blur(8px);
      }

      .mobile-chapter-nav .inner {
        max-width: 800px;
        margin: 0 auto;
        padding: 0.5rem 0.9rem calc(0.5rem + env(safe-area-inset-bottom));
        display: grid;
        grid-template-columns: 1fr auto 1fr;
        gap: 0.5rem;
        align-items: center;
      }

      .mobile-chapter-nav .m-btn {
        display: inline-block;
        text-align: center;
        text-decoration: none;
        border: 1px solid var(--border);
        border-radius: 10px;
        background: var(--card);
        color: var(--text);
        padding: 0.65rem 0.7rem;
        font-family: system-ui, -apple-system, sans-serif;
        font-size: 0.9rem;
        line-height: 1.15;
      }

      .mobile-chapter-nav .m-btn.prev {
        justify-self: start;
      }

      .mobile-chapter-nav .m-btn.toc {
        justify-self: center;
        font-weight: 600;
      }

      .mobile-chapter-nav .m-btn.next {
        justify-self: end;
        border-color: var(--btn-brd);
        background: var(--btn-bg);
        color: var(--btn-text);
        font-weight: 700;
      }

      .mobile-chapter-nav .m-btn.disabled {
        opacity: 0.55;
        pointer-events: none;
      }

      .mobile-chapter-nav .m-btn:focus-visible {
        outline: 2px solid color-mix(in oklab, var(--btn-brd), transparent 35%);
        outline-offset: 2px;
      }

      @media (max-width: 640px) {
        .reader {
          padding-bottom: 6.75rem;
        }

        .reader-settings {
          top: 4.9rem;
          right: 0.5rem;
          width: min(330px, calc(100vw - 1rem));
        }

        .chapter-complete {
          flex-direction: column;
          align-items: stretch;
        }

        .chapter-complete-actions {
          justify-content: stretch;
        }

        .chapter-complete-actions .btn {
          text-align: center;
          width: 100%;
        }

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

        .pager .prev,
        .pager .next,
        .pager .toc {
          justify-self: stretch;
          text-align: center;
        }

        .mobile-chapter-nav {
          display: block;
        }
      }

      @media (prefers-reduced-motion: reduce) {
        .read-progress-fill,
        .pager .btn,
        .chapter-complete-actions .btn,
        .mobile-chapter-nav .m-btn,
        .theme-toggle,
        .reader-settings-reset {
          transition: none;
        }
      }