:root {
      --ink: #1d1d1f;
      --gray: #6e6e73;
      --gray-light: #d2d2d7;
      --card-bg: #fbfbfd;
      --white: #ffffff;
      --sans: -apple-system, "system-ui", "SF Pro Display", "SF Pro Text", "Segoe UI", Roboto, sans-serif;
      --max-w: 980px;
      --gap: 24px;
      --radius: 12px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    html, body {
      font-family: var(--sans);
      background-color: var(--white);
      color: var(--ink);
    }

    /* Navigation — mobile-first */
    nav {
      position: fixed;
      top: 0; left: 0; right: 0;
      height: 49px;
      background: rgba(255,255,255,0.8);
      backdrop-filter: blur(24px);
      border-bottom: 1px solid var(--gray-light);
      z-index: 1000;
    }

    .nav-content {
      max-width: var(--max-w);
      margin: 0 auto;
      padding: 0 var(--gap);
      height: 100%;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .nav-logo {
      font-size: 17px;
      font-weight: 600;
      text-decoration: none;
      color: var(--ink);
      letter-spacing: -0.3px;
    }

    .nav-hamburger {
      display: block;
      background: none;
      border: none;
      cursor: pointer;
      padding: 4px;
      color: var(--ink);
    }

    .nav-hamburger svg {
      width: 22px;
      height: 22px;
    }

    .nav-links {
      display: none;
      position: absolute;
      top: 49px; left: 0; right: 0;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(20px);
      flex-direction: column;
      padding: 16px var(--gap) 24px;
      gap: 0;
      list-style: none;
      border-bottom: 1px solid var(--gray-light);
    }

    .nav-links.open { display: flex; }

    .nav-links li {
      padding-top: 12px; padding-bottom: 12px;
      border-bottom: 1px solid rgba(0,0,0,0.04);
    }

    .nav-links li:last-child {
      border-bottom: none;
      padding-top: 16px;
    }

    .nav-links a {
      font-size: 16px;
      font-weight: 400;
      color: var(--gray);
      text-decoration: none;
      transition: opacity 0.3s cubic-bezier(0.4,0,0.2,1);
    }

    .nav-links a:hover { opacity: 0.7; }

    .lang-toggle {
      font-size: 12px;
      font-weight: 400;
      color: var(--gray);
      background: none;
      border: none;
      cursor: pointer;
      font-family: var(--sans);
      transition: opacity 0.3s cubic-bezier(0.4,0,0.2,1);
    }

    .lang-toggle:hover { opacity: 0.7; }

    /* Main content */
    main {
      padding-top: 49px;
      min-height: 100vh;
    }

    .container {
      max-width: var(--max-w);
      margin: 0 auto;
      padding: 0 var(--gap);
    }

    /* Article header */
    .article-header {
      padding: 80px 0 60px 0;
    }

    .article-header h1 {
      font-size: 48px;
      font-weight: 600;
      line-height: 1.2;
      margin-bottom: 24px;
      color: var(--ink);
      letter-spacing: -0.5px;
    }

    .article-lead {
      font-size: 18px;
      color: var(--gray);
      font-style: italic;
      line-height: 1.7;
      margin-bottom: 32px;
      font-weight: 400;
    }

    .article-divider {
      height: 1px;
      background-color: var(--gray-light);
      margin-bottom: 48px;
    }

    /* Article body */
    .article-body {
      max-width: 720px;
      margin: 0 auto 100px auto;
    }

    .article-body p {
      font-size: 17px;
      line-height: 1.8;
      color: var(--ink);
      margin-bottom: 20px;
    }

    .article-body h2 {
      font-size: 24px;
      font-weight: 600;
      color: var(--ink);
      margin-top: 40px;
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }

    .article-body h2:first-child {
      margin-top: 0;
    }

    /* Author bio */
    .author-bio {
      max-width: 720px;
      margin: 80px auto 100px auto;
      padding-top: 24px;
      border-top: 1px solid var(--gray-light);
      font-size: 14px;
      color: var(--gray);
      line-height: 1.6;
      font-style: italic;
    }

    /* Back link */
    .back-link {
      max-width: 720px;
      margin: 0 auto 60px auto;
      font-size: 14px;
    }

    .back-link a {
      color: var(--gray);
      text-decoration: none;
      transition: color 0.2s;
      display: inline-block;
      padding: 10px 0;
    }

    .back-link a:hover {
      color: var(--ink);
    }

    /* Footer */
    footer {
      background-color: var(--card-bg);
      border-top: 1px solid var(--gray-light);
      padding: 48px var(--gap);
      margin-top: 100px;
    }

    .footer-content {
      max-width: var(--max-w);
      margin: 0 auto;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 14px;
      color: var(--gray);
    }

    .footer-links {
      display: flex;
      list-style: none;
      gap: 32px;
    }

    .footer-links a {
      color: var(--gray);
      text-decoration: none;
      transition: color 0.2s;
    }

    .footer-links a:hover {
      color: var(--ink);
    }

    /* PL/EN toggle handler */
    .lang-only-en {
      display: none;
    }

    html[lang="en"] .lang-only-pl {
      display: none;
    }

    html[lang="en"] .lang-only-en {
      display: block;
    }

    html[lang="en"] .lang-only-pl .article-body,
    html[lang="en"] .lang-only-pl .article-header,
    html[lang="en"] .lang-only-pl .author-bio,
    html[lang="en"] .lang-only-pl .back-link {
      display: none;
    }

    .en-placeholder {
      display: none;
    }

    .en-placeholder .article-header,
    .en-placeholder .article-body,
    .en-placeholder .author-bio,
    .en-placeholder .back-link {
      display: none;
    }

    html[lang="en"] .en-placeholder {
      display: block;
    }

    html[lang="en"] .en-placeholder .article-header,
    html[lang="en"] .en-placeholder .article-body,
    html[lang="en"] .en-placeholder .author-bio,
    html[lang="en"] .en-placeholder .back-link {
      display: block;
    }
    @media (max-width: 768px) {
      body { overflow-x: hidden; }
      .container { padding: 0 20px; }
      .article-header h1 { font-size: 28px; }
      .article-header { padding: 48px 0 32px 0; }
      .article-body p { font-size: 16px; }
      .footer-content { flex-direction: column; gap: 16px; text-align: center; }
      .footer-links { gap: 16px; }
    }
    @media (min-width: 769px) {
      .nav-hamburger { display: none; }
      .nav-links {
        display: flex;
        position: static;
        background: none;
        backdrop-filter: none;
        flex-direction: row;
        padding: 0;
        gap: 32px;
        border-bottom: none;
      }
      .nav-links li {
        padding: 0;
        border-bottom: none;
      }
      .nav-links li:last-child { padding-top: 0; }
      .nav-links a { font-size: 12px; }
      .article-header h1 { font-size: 48px; }
    }
    /* ── dodatki 07.2026: meta, author box, artnav, progress, checklisty ── */
    .article-meta { font-size: 13px; color: var(--gray); margin-bottom: 12px; }

    .read-progress { position: fixed; top: 0; left: 0; height: 2px; width: 0; background: var(--ink); z-index: 2000; }

    .author-box { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; max-width: 720px; margin: 48px auto 0; padding: 24px 0 0; border-top: 1px solid #e8e8ed; }
    .author-photo { width: 56px; height: 56px; object-fit: cover; object-position: center 25%; border-radius: 14px; flex-shrink: 0; }
    .author-info { flex: 1; min-width: 220px; }
    .author-name { font-size: 15px; font-weight: 600; color: var(--ink); }
    .author-desc { font-size: 14px; color: var(--gray); line-height: 1.5; margin-top: 2px; }
    .author-cta { font-size: 13px; font-weight: 500; color: var(--ink); text-decoration: none; border: 1px solid var(--gray-light); border-radius: 980px; padding: 9px 18px; white-space: nowrap; transition: all 0.3s cubic-bezier(0.4,0,0.2,1); }
    .author-cta:hover { background: var(--ink); color: var(--white); border-color: var(--ink); }

    .artnav { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; max-width: 720px; margin: 32px auto 0; }
    .artnav a { color: var(--ink); display: block; padding: 16px 18px; border: 1px solid #e8e8ed; border-radius: 12px; text-decoration: none; background: var(--card-bg); transition: transform 0.3s cubic-bezier(0.16,1,0.3,1), border-color 0.3s ease; }
    .artnav a:hover { transform: translateY(-2px); border-color: #c7c7cc; }
    .artnav a.next { text-align: right; grid-column: 2; }
    .artnav a.prev { grid-column: 1; }
    .article-body a, .article-lead a { color: var(--ink); text-decoration: underline; text-decoration-color: var(--gray-light); text-underline-offset: 3px; transition: text-decoration-color 0.2s; }
    .article-body a:hover, .article-lead a:hover { text-decoration-color: var(--ink); }
    .artnav-dir { font-size: 11px; letter-spacing: 1.5px; text-transform: uppercase; color: var(--gray); margin-bottom: 4px; }
    .artnav-title { font-size: 14px; font-weight: 600; color: var(--ink); }

    .symptom-list { list-style: none; padding: 0; margin: 0 0 20px; max-width: 720px; }
    .symptom-list li { position: relative; padding: 10px 0 10px 30px; border-bottom: 1px solid #e8e8ed; font-size: 16px; line-height: 1.65; color: var(--ink); }
    .symptom-list li:last-child { border-bottom: none; }
    .symptom-list li::before { content: "\2192"; position: absolute; left: 2px; color: var(--gray); }

    @keyframes artIn { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: translateY(0); } }
    .article-header { animation: artIn 0.7s cubic-bezier(0.16,1,0.3,1) both; }
    .article-body { animation: artIn 0.7s cubic-bezier(0.16,1,0.3,1) 0.15s both; }

    @media (prefers-reduced-motion: reduce) {
      .article-header, .article-body { animation: none; }
      .artnav a:hover { transform: none; }
    }

    @media (max-width: 768px) {
      .artnav { grid-template-columns: 1fr; }
      .artnav a.next { grid-column: 1; text-align: left; }
    }

    a:focus-visible, button:focus-visible { outline: 2px solid #1d1d1f; outline-offset: 2px; }

    .apply-box { background: #fbfbfd; border: 1px solid #d2d2d7; border-radius: 12px;
      padding: 20px 24px; margin: 28px 0; font-size: 16px; line-height: 1.6; }
    .apply-label { display: block; font-size: 12px; letter-spacing: 2px;
      text-transform: uppercase; color: #6e6e73; margin-bottom: 8px; font-weight: 600; }
    .article-sources { max-width: 720px; margin: 36px auto 0; padding-top: 12px;
      border-top: 1px solid #e8e8ed; font-size: 12px; line-height: 1.6; color: #6e6e73; }
    .article-sources a { color: #6e6e73; text-decoration: underline; text-underline-offset: 2px; }
    .seria-tag { font-size: 12px; letter-spacing: 2px; text-transform: uppercase;
      color: #6e6e73; margin-bottom: 12px; }