:root {
        --bg: #fbfaf7;
        --surface: #ffffff;
        --surface-2: #f2f0ea;
        --ink: #1c2430;
        --ink-2: #46536a;
        --ink-3: #7c879c;
        --line: #e0dcd2;
        --accent: #0b6fa4;
        --accent-ink: #085a86;
        --amber: #c97a1e;
        --teal: #0f766e;
        --radius: 14px;
        color-scheme: light dark;
      }
      @media (prefers-color-scheme: dark) {
        :root {
          --bg: #10151d;
          --surface: #171e29;
          --surface-2: #1e2735;
          --ink: #e9edf3;
          --ink-2: #b3bfd0;
          --ink-3: #7f8ca1;
          --line: #2b3648;
          --accent: #56b4e0;
          --accent-ink: #8fcfee;
          --amber: #e0a04b;
          --teal: #3ec6b8;
        }
      }
      * { box-sizing: border-box; }
      html { scroll-behavior: smooth; }
      @media (prefers-reduced-motion: reduce) {
        html { scroll-behavior: auto; }
        * { transition: none !important; }
      }
      body {
        margin: 0;
        background: var(--bg);
        color: var(--ink);
        font-family: "Noto Sans SC", system-ui, -apple-system, "PingFang SC", sans-serif;
        font-size: 16px;
        line-height: 1.75;
        -webkit-font-smoothing: antialiased;
      }
      .serif { font-family: "Noto Serif SC", "Songti SC", serif; }
      .mono { font-family: "IBM Plex Mono", ui-monospace, monospace; }
      a { color: var(--accent-ink); }
      button, a.btn, .navlink { min-height: 40px; }

      /* ---------- nav ---------- */
      nav.topnav {
        position: sticky; top: 0; z-index: 20;
        background: color-mix(in srgb, var(--bg) 88%, transparent);
        backdrop-filter: blur(10px);
        border-bottom: 1px solid var(--line);
      }
      .topnav-inner {
        max-width: 1080px; margin: 0 auto; padding: 6px 20px;
        display: flex; align-items: center; gap: 4px; flex-wrap: wrap;
      }
      .brand { font-weight: 700; font-size: 15px; color: var(--ink); text-decoration: none; padding: 8px 10px 8px 0; margin-right: auto; }
      .brand span { color: var(--accent); }
      .navlink {
        display: inline-flex; align-items: center;
        padding: 8px 12px; border-radius: 8px;
        color: var(--ink-2); text-decoration: none; font-size: 14.5px;
      }
      .navlink:hover { color: var(--ink); background: var(--surface-2); }
      .navlink.active { color: var(--accent-ink); font-weight: 700; }

      main { max-width: 1080px; margin: 0 auto; padding: 0 20px 40px; }

      /* ---------- hero ---------- */
      .hero { padding: 44px 0 8px; }
      .hero-art {
        border-radius: 18px; overflow: hidden; border: 1px solid var(--line);
        line-height: 0;
      }
      .hero-art img { width: 100%; height: auto; display: block; }
      .hero h1 {
        font-family: "Noto Serif SC", "Songti SC", serif;
        font-size: clamp(34px, 6vw, 54px); font-weight: 900;
        line-height: 1.25; margin: 34px 0 6px; letter-spacing: .01em;
      }
      .hero .latin { font-size: clamp(15px, 2.4vw, 19px); color: var(--ink-3); letter-spacing: .14em; text-transform: uppercase; font-family: "IBM Plex Mono", monospace; margin: 0 0 18px; }
      .hero .lede { font-size: 17.5px; color: var(--ink-2); max-width: 640px; margin: 0 0 26px; }
      .hero .lede strong { color: var(--ink); }
      .facts { display: flex; flex-wrap: wrap; gap: 10px 26px; padding: 18px 0 4px; border-top: 1px solid var(--line); }
      .fact { font-size: 14.5px; color: var(--ink-2); }
      .fact b { color: var(--ink); font-weight: 700; }
      .fact a { text-decoration: none; }
      .fact a:hover { text-decoration: underline; }

      /* ---------- filter ---------- */
      .filterbar { display: flex; flex-wrap: wrap; gap: 8px; margin: 40px 0 6px; }
      .chip {
        border: 1px solid var(--line); background: var(--surface); color: var(--ink-2);
        border-radius: 999px; padding: 8px 18px; font-size: 15px; cursor: pointer;
        font-family: inherit; min-height: 40px;
        transition: background .15s, color .15s, border-color .15s;
      }
      .chip:hover { border-color: var(--accent); color: var(--ink); }
      .chip[aria-pressed="true"] { background: var(--ink); color: var(--bg); border-color: var(--ink); font-weight: 700; }

      /* ---------- sections ---------- */
      section.work { padding: 34px 0 10px; scroll-margin-top: 70px; }
      section.work[hidden] { display: none; }
      .sec-head { display: flex; align-items: baseline; gap: 14px; margin-bottom: 6px; }
      .sec-head h2 { font-family: "Noto Serif SC", serif; font-size: 27px; font-weight: 900; margin: 0; }
      .sec-head .en { font-family: "IBM Plex Mono", monospace; font-size: 12.5px; letter-spacing: .18em; color: var(--ink-3); text-transform: uppercase; }
      .sec-sub { color: var(--ink-2); margin: 0 0 22px; max-width: 660px; }

      /* project card */
      .project {
        background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
        padding: 26px 26px 22px; margin-bottom: 18px;
      }
      .project .tag-row { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 12px; }
      .tag { font-size: 12.5px; padding: 3px 10px; border-radius: 999px; background: var(--surface-2); color: var(--ink-2); border: 1px solid var(--line); }
      .tag.hot { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 700; }
      @media (prefers-color-scheme: dark) { .tag.hot { color: #0b1520; } }
      .project h3 { font-family: "Noto Serif SC", serif; font-size: 22px; margin: 0 0 8px; font-weight: 900; }
      .project p { color: var(--ink-2); margin: 0 0 14px; }
      .project p b { color: var(--ink); }
      .pipeline { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin: 16px 0 6px; }
      .step {
        font-size: 13.5px; padding: 5px 12px; border-radius: 8px;
        background: var(--surface-2); border: 1px solid var(--line); color: var(--ink);
        font-weight: 500;
      }
      .arrow { color: var(--ink-3); font-size: 13px; }
      .trust { margin-top: 16px; border-top: 1px dashed var(--line); padding-top: 14px; }
      .trust .t-title { font-size: 14px; font-weight: 700; margin-bottom: 8px; }
      .trust ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 6px; }
      .trust li { font-size: 14.5px; color: var(--ink-2); display: flex; gap: 9px; align-items: baseline; }
      .dot { width: 11px; height: 11px; border-radius: 3px; flex: none; position: relative; top: 1px; border: 1px solid rgba(0,0,0,.18); }
      .dot.white { background: #f4f4f2; }
      .dot.cyan { background: #7fd8dc; }
      .dot.green { background: #4caf7d; }
      .dot.red { background: #d9534f; }
      .trust li b { color: var(--ink); }
      .project .links { margin-top: 18px; display: flex; flex-wrap: wrap; gap: 10px; }
      .btn {
        display: inline-flex; align-items: center; gap: 7px;
        padding: 9px 18px; border-radius: 9px; text-decoration: none;
        font-size: 15px; font-weight: 700; border: 1px solid var(--ink);
        background: var(--ink); color: var(--bg);
      }
      .btn.ghost { background: transparent; color: var(--ink); border-color: var(--line); }
      .btn:hover { opacity: .88; }
      .mini-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
      @media (max-width: 720px) { .mini-grid { grid-template-columns: 1fr; } }
      .mini { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 22px; }
      .mini h3 { font-size: 17.5px; margin: 0 0 6px; font-family: "Noto Serif SC", serif; font-weight: 900; }
      .mini p { color: var(--ink-2); font-size: 14.5px; margin: 0 0 12px; }
      .mini a { font-size: 14.5px; font-weight: 700; text-decoration: none; }
      .mini a:hover { text-decoration: underline; }

      /* empty states */
      .empty {
        border: 1.5px dashed var(--line); border-radius: var(--radius);
        padding: 30px 26px; text-align: center; background: var(--surface);
      }
      .empty .big { font-family: "Noto Serif SC", serif; font-size: 19px; font-weight: 900; margin: 0 0 6px; }
      .empty p { color: var(--ink-2); margin: 0 auto; max-width: 480px; font-size: 15px; }
      .frames { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-bottom: 18px; }
      @media (max-width: 720px) { .frames { grid-template-columns: 1fr 1fr; } }
      .frame {
        aspect-ratio: 4 / 3; border: 1.5px dashed var(--line); border-radius: 10px;
        display: flex; align-items: center; justify-content: center;
        color: var(--ink-3); font-size: 13.5px; background: var(--surface);
        text-align: center; padding: 10px;
      }
      .frame.tall { aspect-ratio: 3 / 4; }

      /* about / roadmap */
      .about-grid { display: grid; grid-template-columns: 1fr; gap: 18px; max-width: 760px; }
      @media (max-width: 720px) { .about-grid { grid-template-columns: 1fr; } }
      .panel { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px 26px; }
      .panel h3 { font-family: "Noto Serif SC", serif; font-size: 19px; margin: 0 0 10px; font-weight: 900; }
      .panel p { color: var(--ink-2); margin: 0 0 10px; font-size: 15.5px; }
      .panel p.wish { color: var(--ink); font-size: 30px; font-weight: 900; line-height: 1.4; margin: 14px 0 16px; }
      .panel ol { margin: 0; padding-left: 20px; color: var(--ink-2); font-size: 15.5px; }
      .panel ol li { margin-bottom: 7px; }
      .panel ol li b { color: var(--ink); }
      .done { color: var(--teal); font-weight: 700; font-size: 13px; margin-left: 6px; }
      .todo { color: var(--amber); font-weight: 700; font-size: 13px; margin-left: 6px; }

      footer {
        margin-top: 44px; border-top: 1px solid var(--line); padding: 24px 0 10px;
        display: flex; flex-wrap: wrap; gap: 8px 26px; align-items: center;
        color: var(--ink-3); font-size: 14px;
      }
      footer a { text-decoration: none; font-weight: 500; }
      footer a:hover { text-decoration: underline; }
      .copybtn {
        border: 1px solid var(--line); background: var(--surface); color: var(--ink-2);
        border-radius: 8px; padding: 6px 12px; font-size: 13.5px; cursor: pointer; font-family: inherit;
      }
      .copybtn:hover { color: var(--ink); border-color: var(--accent); }

      /* ---------- ebook search ---------- */
      .ebook-form { display: flex; flex-wrap: wrap; gap: 10px; align-items: end; margin: 16px 0 4px; }
      .ebook-form label { display: flex; flex-direction: column; gap: 6px; font-size: 14px; color: var(--ink-2); }
      .ebook-form input { padding: 10px 12px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); color: var(--ink); font-size: 15px; min-width: 200px; }
      .ebook-form input:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
      .ebook-status { color: var(--ink-2); font-size: 14px; min-height: 20px; margin: 10px 0 0; }
      .ebook-results { list-style: none; padding: 0; margin: 12px 0 0; display: grid; gap: 10px; }
      .ebook-results li { border: 1px solid var(--line); border-radius: var(--radius); padding: 12px 14px; background: var(--surface); }
      .ebook-results .v { font-size: 13px; color: var(--ink-3); margin-top: 4px; }

      /* 数据驱动的条目卡片（writing / design / media 由内容清单渲染） */
      [hidden] { display: none !important; }
      .mini p.entry-meta { font-size: 13px; color: var(--ink-3); margin-bottom: 6px; }
      .mini img.thumb { width: 100%; height: auto; display: block; border-radius: 8px; margin-bottom: 12px; }