:root {
      --blue: #326599;
      --blue-dark: #20558a;
      --link: #21549b;
      --plum: #70579d;
      --green: #497f3f;
      --green-bg: #eaf3e2;
      --text: #1c1c1c;
      --muted: #5b5b5b;
      --line: #d4d4d4;
      --line-soft: #e8e8e8;
      --bg: #ffffff;
      --bg-soft: #f7f7f7;
    }
    * { box-sizing: border-box; }
    body {
      margin: 0;
      background: var(--bg);
      color: var(--text);
      font-family: "Nunito Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
      font-size: 16px;
      line-height: 1.55;
    }
    a { color: var(--link); text-decoration: none; }
    a:hover { text-decoration: underline; }

    .topbar {
      background: #262626;
      color: #e6e6e6;
      font-size: 0.78rem;
    }
    .topbar-inner {
      max-width: 1100px;
      margin: 0 auto;
      padding: 0.4rem 1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .topbar a { color: #cfd8e3; margin-left: 1.1rem; }

    .masthead {
      border-bottom: 1px solid var(--line);
      background: var(--bg);
    }
    .masthead-inner {
      max-width: 1100px;
      margin: 0 auto;
      padding: 1.4rem 1rem;
      display: flex;
      align-items: center;
      gap: 2rem;
      flex-wrap: wrap;
    }
    .logo {
      font-size: 2.1rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      color: var(--blue);
      white-space: nowrap;
    }
    .logo .dot { color: #c0392b; }
    .logo small {
      display: block;
      font-size: 0.72rem;
      font-weight: 600;
      color: var(--muted);
      letter-spacing: 0.08em;
      text-transform: uppercase;
    }
    .searchbox {
      flex: 1;
      min-width: 280px;
      max-width: 640px;
      display: flex;
    }
    .searchbox input {
      flex: 1;
      font: inherit;
      font-size: 1.05rem;
      padding: 0.65rem 0.9rem;
      border: 2px solid var(--blue);
      border-right: none;
      border-radius: 6px 0 0 6px;
      outline: none;
    }
    .searchbox button {
      font: inherit;
      font-weight: 700;
      font-size: 1.05rem;
      color: #fff;
      background: var(--blue);
      border: 2px solid var(--blue);
      border-radius: 0 6px 6px 0;
      padding: 0.65rem 1.4rem;
      cursor: pointer;
    }
    .searchbox button:hover { background: var(--blue-dark); }
    .submit-link {
      white-space: nowrap;
      font-weight: 700;
      font-size: 0.82rem;
      color: #fff;
      background: var(--blue);
      border-radius: 5px;
      padding: 0.42rem 0.8rem;
    }
    .submit-link:hover {
      text-decoration: none;
      background: var(--blue-dark);
    }

    .crumb {
      max-width: 1100px;
      margin: 0 auto;
      padding: 0.6rem 1rem;
      font-size: 0.82rem;
      color: var(--muted);
    }

    .layout {
      max-width: 820px;
      margin: 0 auto;
      padding: 1rem 1rem 3rem;
    }

    .toolbar {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 1rem;
      flex-wrap: wrap;
      padding-bottom: 0.7rem;
      border-bottom: 1px solid var(--line);
      margin-bottom: 1.2rem;
    }
    .toolbar .status { font-size: 0.95rem; color: var(--muted); }
    .toolbar .status strong { color: var(--text); }
    .toolbar select {
      font: inherit;
      font-size: 0.85rem;
      padding: 0.3rem 0.5rem;
      border: 1px solid var(--line);
      border-radius: 4px;
      background: var(--bg);
      color: var(--muted);
    }

    .result {
      display: flex;
      gap: 0.9rem;
      padding: 1.1rem 0;
      border-bottom: 1px solid var(--line-soft);
    }
    .result .r-num {
      font-size: 0.9rem;
      color: var(--muted);
      min-width: 1.6rem;
      padding-top: 0.2rem;
    }
    .r-title {
      font-size: 1.22rem;
      font-weight: 700;
      line-height: 1.35;
      margin: 0 0 0.35rem;
    }
    .r-title a { color: var(--link); }
    .r-authors { margin: 0 0 0.15rem; font-size: 0.95rem; }
    .r-source { margin: 0 0 0.7rem; font-size: 0.92rem; color: var(--plum); }
    .chip {
      display: inline-block;
      font-size: 0.72rem;
      font-weight: 700;
      border-radius: 3px;
      padding: 0.1rem 0.5rem;
      margin-left: 0.5rem;
      vertical-align: 1px;
    }
    .chip-free { color: var(--green); background: var(--green-bg); }
    .chip-type { color: var(--muted); background: var(--bg-soft); border: 1px solid var(--line-soft); }

    .r-abstract { font-size: 0.93rem; color: #333; }
    .r-abstract h4 {
      font-size: 0.8rem;
      text-transform: uppercase;
      letter-spacing: 0.06em;
      color: var(--muted);
      margin: 0 0 0.25rem;
    }
    .r-mesh { margin-top: 0.8rem; font-size: 0.82rem; color: var(--muted); }
    .r-mesh strong { font-weight: 700; }
    .r-mesh a { margin-right: 0.9rem; white-space: nowrap; }
    .r-links { margin-top: 0.7rem; font-size: 0.85rem; }
    .r-links a { margin-right: 1.1rem; }

    .refs {
      margin: 0.9rem 0 0;
      padding: 0.8rem 1rem;
      background: var(--bg-soft);
      border-radius: 6px;
      font-size: 0.83rem;
    }
    .refs h4 {
      margin: 0 0 0.4rem;
      font-size: 0.78rem;
      text-transform: uppercase;
      letter-spacing: 0.06em;
      color: var(--muted);
    }
    .refs ol { margin: 0; padding-left: 1.3rem; }
    .refs li { margin: 0.25rem 0; color: #444; }

    .no-results {
      display: none;
      padding: 2.5rem 0;
      text-align: center;
      color: var(--muted);
    }
    .no-results button {
      font: inherit;
      margin-top: 0.8rem;
      padding: 0.45rem 1.1rem;
      border: 1px solid var(--line);
      border-radius: 4px;
      background: var(--bg-soft);
      cursor: pointer;
    }

    .footer {
      border-top: 1px solid var(--line);
      background: var(--bg-soft);
      font-size: 0.8rem;
      color: var(--muted);
    }
    .footer-inner {
      max-width: 820px;
      margin: 0 auto;
      padding: 1.4rem 1rem;
      text-align: center;
    }
    .footer-inner p { margin: 0; line-height: 1.7; }