:root {
        --bg: #ffffff;
        --text: #171717;
        --muted: #5f6368;
        --line: #e6e6e6;
        --soft: #f7f7f7;
        --code: #f4f4f4;
        --accent: #111111;
        --max: 760px;
      }

      * {
        box-sizing: border-box;
      }

      html {
        background: var(--bg);
        color: var(--text);
        font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
          "Noto Sans CJK SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
        line-height: 1.7;
        text-rendering: optimizeLegibility;
        -webkit-text-size-adjust: 100%;
      }

      body {
        margin: 0;
        min-height: 100vh;
        font-size: 16px;
      }

      a {
        color: inherit;
        text-decoration-thickness: 1px;
        text-underline-offset: 0.2em;
      }

      a:hover {
        color: #000000;
      }

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

      .skip-link {
        position: absolute;
        left: 1rem;
        top: -4rem;
        z-index: 10;
        background: var(--text);
        color: var(--bg);
        padding: 0.5rem 0.75rem;
      }

      .skip-link:focus {
        top: 1rem;
      }

      .site-header {
        border-bottom: 1px solid var(--line);
      }

      .site-header__inner,
      main,
      .site-footer__inner {
        width: min(100% - 2rem, var(--max));
        margin-inline: auto;
      }

      .site-header__inner {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: 1rem;
        padding: 1rem 0;
      }

      .brand {
        font-weight: 700;
        letter-spacing: 0;
        text-decoration: none;
      }

      .nav {
        display: flex;
        align-items: center;
        gap: 0.9rem;
        color: var(--muted);
        font-size: 0.95rem;
      }

      .nav a[aria-current="page"] {
        color: var(--text);
        font-weight: 600;
      }

      main {
        padding: 2.5rem 0 4rem;
      }

      .site-footer {
        border-top: 1px solid var(--line);
        color: var(--muted);
        font-size: 0.92rem;
      }

      .site-footer__inner {
        padding: 1.5rem 0;
      }

      h1,
      h2,
      h3 {
        line-height: 1.3;
        letter-spacing: 0;
      }

      h1 {
        margin: 0 0 1rem;
        font-size: clamp(2rem, 7vw, 3.2rem);
      }

      h2 {
        margin: 2.5rem 0 0.9rem;
        font-size: 1.45rem;
      }

      h3 {
        margin: 2rem 0 0.75rem;
        font-size: 1.12rem;
      }

      p {
        margin: 0 0 1.1rem;
      }

      .lead {
        color: var(--muted);
        font-size: 1.08rem;
      }

      .section-heading {
        display: flex;
        align-items: baseline;
        justify-content: space-between;
        gap: 1rem;
        border-top: 1px solid var(--line);
        margin-top: 2.5rem;
        padding-top: 1.4rem;
      }

      .section-heading h2 {
        margin: 0;
      }

      .article-list {
        display: grid;
        gap: 1.35rem;
        margin: 1.25rem 0 0;
        padding: 0;
        list-style: none;
      }

      .article-item {
        border-bottom: 1px solid var(--line);
        padding-bottom: 1.35rem;
      }

      .article-item:last-child {
        border-bottom: 0;
      }

      .article-item h2,
      .article-item h3 {
        margin: 0 0 0.35rem;
        font-size: 1.2rem;
      }

      .meta {
        color: var(--muted);
        font-size: 0.92rem;
      }

      .prose {
        font-size: 1.02rem;
      }

      .prose > :first-child {
        margin-top: 0;
      }

      .prose ul,
      .prose ol {
        padding-left: 1.4rem;
      }

      .prose li {
        margin-bottom: 0.45rem;
      }

      .prose blockquote {
        border-left: 3px solid var(--line);
        color: var(--muted);
        margin: 1.5rem 0;
        padding-left: 1rem;
      }

      code {
        background: var(--code);
        border-radius: 4px;
        font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
        font-size: 0.92em;
        padding: 0.1rem 0.25rem;
      }

      pre {
        background: var(--soft);
        border: 1px solid var(--line);
        border-radius: 8px;
        overflow-x: auto;
        padding: 1rem;
      }

      pre code {
        background: transparent;
        border-radius: 0;
        padding: 0;
      }

      .page-actions {
        display: flex;
        flex-wrap: wrap;
        gap: 0.8rem;
        margin-top: 1.5rem;
      }

      .button {
        border: 1px solid var(--text);
        border-radius: 6px;
        display: inline-flex;
        font-weight: 600;
        line-height: 1;
        padding: 0.75rem 0.9rem;
        text-decoration: none;
      }

      .button.secondary {
        border-color: var(--line);
        color: var(--muted);
      }

      .note {
        background: var(--soft);
        border: 1px solid var(--line);
        border-radius: 8px;
        color: var(--muted);
        padding: 1rem;
      }

      @media (max-width: 560px) {
        .site-header__inner {
          align-items: flex-start;
          flex-direction: column;
        }

        .nav {
          width: 100%;
          justify-content: flex-start;
        }
      }

      @media print {
        .site-header,
        .site-footer,
        .page-actions {
          display: none;
        }

        main {
          width: 100%;
          padding: 0;
        }

        a {
          text-decoration: none;
        }

        body {
          color: #000000;
        }
      }