:root {
    /* Duo-inspired palette — green primary, owl orange retained for trade brand continuity */
    --bg: #ffffff;
    --bg-soft: #fff8e7;        /* cream highlight wash */
    --surface: #ffffff;
    --ink: #3c3c3c;            /* Duo body */
    --ink-muted: #777777;
    --border: #e5e5e5;
    --border-strong: #d0d0d0;
    --green: #58cc02;          /* Duo green */
    --green-dark: #46a302;     /* button bottom-shadow */
    --green-bg: #d7ffb8;
    --orange: #ff9600;         /* JW brand carryover, Duo owl */
    --orange-dark: #e08400;
    --yellow: #ffc800;
    --blue: #1cb0f6;
    --blue-dark: #1899d6;
    --red: #ff4b4b;
  }
  * { box-sizing: border-box; }
  html, body { margin: 0; padding: 0; }
  body {
    background: var(--bg); color: var(--ink);
    font-family: 'Nunito', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    font-weight: 500;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
  }
  .wrap { max-width: 760px; margin: 0 auto; padding: 24px 20px 60px; }

  /* HEADER + MASCOT */
  header { margin-bottom: 28px; text-align: center; }
  .brand-row {
    display: inline-flex; align-items: center; gap: 10px;
    margin-bottom: 14px;
  }
  .brand-mark {
    width: 44px; height: 44px;
    background: var(--yellow); border-radius: 50%;
    border-bottom: 4px solid #d9a900;
    display: inline-flex; align-items: center; justify-content: center;
  }
  .brand-mark svg { width: 24px; height: 24px; }
  .brand {
    font-size: 18px; font-weight: 900; color: var(--ink);
    letter-spacing: -0.01em; text-transform: uppercase;
  }
  h1 {
    font-size: 32px; line-height: 1.15; letter-spacing: -0.02em;
    margin: 4px 0 14px; font-weight: 900; color: var(--ink);
  }
  @media (min-width: 720px) { h1 { font-size: 44px; } }
  .sub {
    font-size: 17px; color: var(--ink-muted); margin: 0 auto 24px;
    line-height: 1.5; font-weight: 600; max-width: 580px;
  }

  /* STAT CHIPS — gamified achievement style */
  .stat-strip {
    display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px;
    margin-bottom: 28px;
  }
  @media (min-width: 720px) { .stat-strip { grid-template-columns: repeat(4, 1fr); } }
  .stat {
    background: #fff; border: 2px solid var(--border);
    border-radius: 14px; padding: 14px 12px;
    text-align: center; font-size: 12px; color: var(--ink-muted);
    font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em;
  }
  .stat strong {
    display: block; font-size: 22px; font-weight: 900; color: var(--ink);
    margin-bottom: 2px; font-variant-numeric: tabular-nums;
    letter-spacing: -0.02em; text-transform: none;
  }
  .stat.alert strong { color: var(--red); }
  .stat.warn strong { color: var(--orange); }

  /* TRUST CHIPS (F7) — credibility signals in place of absent client logos */
  .trust-chips {
    display: flex; flex-wrap: wrap; justify-content: center; gap: 8px;
    margin: -14px 0 28px;
  }
  .trust-chips span {
    font-size: 12px; font-weight: 800; color: var(--ink-muted);
    background: #fff; border: 2px solid var(--border); border-radius: 999px;
    padding: 6px 12px; letter-spacing: 0.02em; white-space: nowrap;
  }

  /* FEATURE CARDS — Duo lesson tile style */
  .features { margin: 0 0 24px; padding: 0; list-style: none;
    display: grid; gap: 12px; }
  .features li {
    background: #fff; border: 2px solid var(--border);
    border-radius: 16px; padding: 16px 18px;
    display: flex; align-items: flex-start; gap: 14px;
    transition: transform .12s, border-color .12s;
  }
  .features li:hover { border-color: var(--border); }
  .features .check {
    flex: 0 0 32px; height: 32px; border-radius: 50%;
    background: var(--green); color: #fff;
    border-bottom: 3px solid var(--green-dark);
    display: inline-flex; align-items: center; justify-content: center;
    font-weight: 900; font-size: 16px;
  }
  .features .body strong {
    display: block; font-size: 16px; font-weight: 800;
    color: var(--ink); margin-bottom: 4px;
  }
  .features .body span { font-size: 14px; color: var(--ink-muted); font-weight: 500; }

  /* PRODUCT SHOT (F6) — real question-browser proof */
  .shot { margin: 28px 0; text-align: center; }
  .shot-head { font-size: 18px; font-weight: 900; color: var(--ink); margin: 0 0 12px; letter-spacing: -0.01em; }
  .shot-frame {
    border: 2px solid var(--border); border-radius: 16px; overflow: hidden;
    background: #fff; box-shadow: 0 6px 0 rgba(0,0,0,0.06);
  }
  .shot-frame img { display: block; width: 100%; height: auto; }
  .shot-sub { font-size: 13px; color: var(--ink-muted); font-weight: 600; margin: 12px 0 0; }

  /* HONEST PROOF BLOCK (F4) — no fabricated reviews; verifiable specifics + "be first" */
  .proof { background: var(--bg-soft); border: 2px solid var(--yellow); border-radius: 16px; padding: 22px; margin: 28px 0; }
  .proof-badge { display: inline-block; background: var(--green); color: #fff; font-size: 11px; font-weight: 900; text-transform: uppercase; letter-spacing: 0.06em; padding: 4px 10px; border-radius: 999px; border-bottom: 3px solid var(--green-dark); }
  .proof-status strong { display: block; font-size: 18px; font-weight: 900; color: var(--ink); margin: 10px 0 4px; letter-spacing: -0.01em; }
  .proof-status p { margin: 0 0 14px; font-size: 14px; color: var(--ink-muted); font-weight: 600; }
  .proof-points { margin: 0; padding: 0; list-style: none; display: grid; gap: 9px; }
  .proof-points li { font-size: 14px; color: var(--ink); font-weight: 500; line-height: 1.5; padding-left: 26px; position: relative; }
  .proof-points li::before { content: "✓"; position: absolute; left: 0; top: 0; color: var(--green-dark); font-weight: 900; }
  .proof-points b { font-weight: 800; }
  .proof-forum { margin: 16px 0 0; padding-top: 14px; border-top: 1px solid var(--border); font-size: 13px; color: var(--ink-muted); font-weight: 600; line-height: 1.55; }
  .proof-forum em { font-style: italic; }
  .proof-forum .src { display: block; margin-top: 4px; font-size: 12px; }

  /* PDF PREVIEW CARD */
  .pdf-preview {
    margin: 24px 0; background: var(--bg-soft);
    border: 2px solid var(--yellow);
    border-radius: 16px; padding: 20px;
    display: flex; gap: 18px; align-items: flex-start;
  }
  .pdf-preview-img-wrap {
    flex: 0 0 130px; border: 2px solid #fff; border-radius: 8px;
    overflow: hidden; box-shadow: 0 4px 0 rgba(0,0,0,0.08);
  }
  .pdf-preview-img-wrap img { display: block; width: 100%; height: auto; }
  .pdf-preview-text { flex: 1; min-width: 0; }
  .pdf-preview-text h3 { margin: 0 0 8px; font-size: 17px; font-weight: 800; }
  .pdf-preview-text p { margin: 0; font-size: 14px; color: var(--ink); line-height: 1.5; font-weight: 500; }
  @media (max-width: 520px) {
    .pdf-preview { flex-direction: column; }
    .pdf-preview-img-wrap { flex: 0 0 auto; max-width: 180px; align-self: center; }
  }

  /* SIGNUP — chunky CTA card */
  .signup {
    background: #fff; border: 2px solid var(--green);
    border-radius: 20px; padding: 24px 22px; margin: 32px 0;
    box-shadow: 0 6px 0 var(--green-dark);
  }
  .signup h2 {
    margin: 0 0 6px; font-size: 22px; font-weight: 900;
    color: var(--ink); letter-spacing: -0.01em;
  }
  .signup p { margin: 0 0 16px; color: var(--ink-muted); font-size: 14px; font-weight: 600; }
  .signup form { display: flex; gap: 10px; flex-wrap: wrap; }
  .signup input[type="email"] {
    flex: 1; min-width: 200px;
    padding: 14px 16px; border: 2px solid var(--border); border-radius: 12px;
    font: inherit; font-size: 16px; font-weight: 600;
    background: #fff; color: var(--ink);
  }
  .signup input[type="email"]:focus {
    outline: none; border-color: var(--blue);
    box-shadow: 0 0 0 3px rgba(28,176,246,0.15);
  }
  /* DUO BUTTON */
  .signup button {
    padding: 13px 22px; border: 2px solid var(--green);
    border-radius: 12px;
    background: #fff; color: var(--green-dark);
    font: inherit; font-size: 14px; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.04em;
    cursor: pointer; transition: background .12s, color .12s, transform .06s;
  }
  .signup button:hover { background: var(--green-bg); }
  .signup button:active { transform: translateY(1px); }
  .signup button:disabled { opacity: 0.6; cursor: wait; }
  .signup .small { font-size: 12px; color: var(--ink-muted); margin-top: 12px; font-weight: 600; }

  /* HERO CTA — primary buy button above the fold (added 2026-06-02) */
  .hero-cta-wrap { text-align: center; margin: 6px 0 30px; }
  .hero-cta {
    display: inline-block; padding: 16px 34px;
    border: none; border-bottom: 4px solid var(--green-dark);
    border-radius: 14px; background: var(--green); color: #fff;
    font: inherit; font-size: 17px; font-weight: 800;
    text-transform: uppercase; letter-spacing: 0.04em;
    text-decoration: none; cursor: pointer;
    transition: filter .12s, transform .06s, border-bottom-width .06s;
  }
  .hero-cta:hover { filter: brightness(1.05); }
  .hero-cta:active { border-bottom-width: 0; transform: translateY(4px); }
  .hero-cta-sub { display: block; margin-top: 12px; font-size: 13px; color: var(--ink-muted); font-weight: 700; }
  .hero-cta-sub a { color: var(--blue); text-decoration: none; }

  /* CIRCUIT HERO — current flowing into the NEC code (vanilla SVG + CSS) */
  .circuit-hero { width: 100%; max-width: 460px; margin: 4px auto 18px; display: block; color: #dfe6df; }
  .circuit-flow {
    offset-anchor: 10px 0px;
    animation: circuit-path infinite cubic-bezier(0.75,-0.01,0,0.99);
  }
  .cl-1 { offset-path: path("M 10 20 h 79.5 q 5 0 5 5 v 30"); animation-duration: 5s; animation-delay: 1s; }
  .cl-2 { offset-path: path("M 180 10 h -69.7 q -5 0 -5 5 v 40"); animation-delay: 6s; animation-duration: 2s; }
  .cl-3 { offset-path: path("M 130 20 v 21.8 q 0 5 -5 5 h -25"); animation-delay: 4s; animation-duration: 6s; }
  .cl-4 { offset-path: path("M 170 80 v -21.8 q 0 -5 -5 -5 h -65"); animation-delay: 3s; animation-duration: 3s; }
  .cl-5 { offset-path: path("M 135 65 h 15 q 5 0 5 5 v 10 q 0 5 -5 5 h -39.8 q -5 0 -5 -5 v -35"); animation-delay: 9s; animation-duration: 4s; }
  .cl-6 { offset-path: path("M 94.8 95 v -46"); animation-delay: 3s; animation-duration: 7s; }
  .cl-7 { offset-path: path("M 88 88 v -15 q 0 -5 -5 -5 h -10 q -5 0 -5 -5 v -5 q 0 -5 5 -5 h 28"); animation-delay: 4s; animation-duration: 4s; }
  .cl-8 { offset-path: path("M 30 30 h 25 q 5 0 5 5 v 6.5 q 0 5 5 5 h 35"); animation-delay: 3s; animation-duration: 3s; }
  @keyframes circuit-path { 0% { offset-distance: 0%; } 100% { offset-distance: 100%; } }
  @media (prefers-reduced-motion: reduce) { .circuit-flow { animation: none; } }

  /* QUOTE — speech-bubble style */
  .quote {
    background: #fff; border: 2px solid var(--border);
    border-radius: 16px; padding: 18px 20px; margin: 28px 0;
    font-size: 15px; color: var(--ink); line-height: 1.55;
    font-weight: 600; font-style: italic;
    position: relative;
  }
  .quote::before {
    content: '\201C'; position: absolute; top: -12px; left: 16px;
    background: var(--orange); color: #fff;
    width: 32px; height: 32px; border-radius: 50%;
    border-bottom: 3px solid var(--orange-dark);
    display: flex; align-items: center; justify-content: center;
    font-size: 28px; font-weight: 900; font-style: normal;
    line-height: 1; padding-bottom: 6px;
  }
  .quote .who {
    display: block; font-size: 13px; color: var(--ink-muted);
    margin-top: 8px; font-style: normal; font-weight: 600;
  }

  /* FAQ */
  .faq { margin: 36px 0 24px; }
  .faq h2 {
    font-size: 24px; margin: 0 0 18px; font-weight: 900;
    text-align: center; letter-spacing: -0.01em;
  }
  .faq-item {
    background: #fff; border: 2px solid var(--border);
    border-radius: 14px; padding: 16px 18px; margin-bottom: 10px;
    transition: border-color .12s;
  }
  .faq-item:hover { border-color: var(--blue); }
  .faq-item h3 {
    font-size: 15px; font-weight: 800; margin: 0 0 6px; color: var(--ink);
  }
  .faq-item p { margin: 0; font-size: 14px; color: var(--ink-muted); line-height: 1.55; font-weight: 500; }

  footer {
    color: var(--ink-muted); font-size: 12px; margin-top: 40px;
    line-height: 1.6; text-align: center; font-weight: 600;
  }

  /* EMBEDDED 3-Q QUIZ — added 2026-05-12 per marketing-audit */
  .quiz {
    background: #fff; border: 2px solid var(--orange); border-radius: 20px;
    padding: 22px 20px; margin: 0 0 28px;
    box-shadow: 0 6px 0 var(--orange-dark);
  }
  .quiz-head { display: flex; align-items: center; gap: 10px; margin-bottom: 4px; }
  .quiz-head .badge {
    background: var(--orange); color: #fff; font-weight: 900;
    font-size: 11px; letter-spacing: 0.06em; text-transform: uppercase;
    padding: 4px 10px; border-radius: 999px;
    border-bottom: 3px solid var(--orange-dark);
  }
  .quiz h2 { margin: 0 0 4px; font-size: 20px; font-weight: 900; letter-spacing: -0.01em; }
  .quiz .quiz-sub { margin: 0 0 18px; font-size: 14px; color: var(--ink-muted); font-weight: 600; }
  .q-card { border-top: 1px solid var(--border); padding-top: 16px; margin-top: 16px; }
  .q-card:first-of-type { border-top: none; padding-top: 0; margin-top: 0; }
  .q-meta { font-size: 12px; color: var(--ink-muted); font-weight: 700; text-transform: uppercase; letter-spacing: 0.04em; margin-bottom: 6px; }
  .q-stem { font-size: 15px; font-weight: 700; color: var(--ink); margin: 0 0 12px; line-height: 1.5; }
  .q-options { display: grid; gap: 8px; }
  .q-opt {
    text-align: left; padding: 12px 14px;
    background: #fff; border: 2px solid var(--border); border-radius: 12px;
    font: inherit; font-size: 14px; font-weight: 600; color: var(--ink);
    cursor: pointer; transition: border-color .12s, background .12s, transform .06s;
  }
  .q-opt:hover:not(:disabled) { border-color: var(--blue); }
  .q-opt:disabled { cursor: default; }
  .q-opt.correct { background: var(--green-bg); border-color: var(--green); color: #1f6b00; font-weight: 800; }
  .q-opt.wrong { background: #ffe5e5; border-color: var(--red); color: #8a1818; }
  .q-opt.was-correct { background: var(--green-bg); border-color: var(--green); color: #1f6b00; font-weight: 800; }
  .q-solution {
    margin-top: 12px; padding: 12px 14px; background: var(--bg-soft);
    border: 2px solid var(--yellow); border-radius: 10px;
    font-size: 13px; line-height: 1.55; color: var(--ink); font-weight: 600;
  }
  .q-solution .ref { font-weight: 900; color: var(--ink); }
  .quiz-bar { height: 12px; background: var(--border); border-radius: 999px; margin-top: 16px; overflow: hidden; }
  .quiz-bar > i { display: block; height: 100%; width: 0; background: var(--green); border-radius: 999px; transition: width .35s ease; }
  .quiz-progress {
    margin-top: 14px; font-size: 13px; color: var(--ink-muted); font-weight: 700;
    display: flex; justify-content: space-between; align-items: center;
  }
  .quiz-cta {
    display: block; margin-top: 18px; padding: 16px 18px;
    background: var(--green-bg); border: 2px solid var(--green);
    border-radius: 14px; text-align: center;
  }
  .quiz-cta.show { display: block; }
  .quiz-cta strong { display: block; font-size: 17px; font-weight: 900; color: #1f6b00; margin-bottom: 6px; }
  .quiz-cta a {
    display: inline-block; margin-top: 10px;
    padding: 12px 20px; border: none; border-bottom: 4px solid var(--green-dark);
    border-radius: 12px; background: var(--green); color: #fff;
    font: inherit; font-size: 14px; font-weight: 800;
    text-transform: uppercase; letter-spacing: 0.04em;
    text-decoration: none; cursor: pointer;
  }
  .quiz-cta-alt { display: block; margin-top: 12px; }
  .quiz-cta-alt a {
    display: inline; margin: 0; padding: 0; border: none; background: none;
    color: var(--blue); font-size: 13px; font-weight: 700;
    text-transform: none; letter-spacing: 0; text-decoration: none;
  }

  /* THANKS confirmation — celebration style */
  .thanks {
    background: var(--green-bg); color: #1f6b00;
    border: 2px solid var(--green); border-radius: 14px;
    padding: 16px 18px; font-size: 15px; font-weight: 800;

  /* ANNOUNCE BAR (F10) */
  .announce{display:flex;align-items:center;justify-content:center;gap:10px;background:var(--bg-soft,#fff8e7);border-bottom:2px solid var(--yellow,#ffc800);padding:8px 14px;font-size:13px;font-weight:700;color:var(--ink,#3c3c3c);text-align:center;line-height:1.4;}
  .announce a{color:var(--green-dark,#46a302);text-decoration:none;font-weight:800;}
  .announce button{flex:0 0 auto;border:none;background:transparent;color:var(--ink-muted,#777);font-size:18px;line-height:1;cursor:pointer;padding:0 4px;}
  @media(max-width:520px){.announce{font-size:12px;}}
  /* FAQ ACCORDION (F12) */
  .faq-item summary{cursor:pointer;font-size:15px;font-weight:800;color:var(--ink,#3c3c3c);list-style:none;display:flex;justify-content:space-between;align-items:center;gap:10px;}
  .faq-item summary::-webkit-details-marker{display:none;}
  .faq-item summary::after{content:"+";color:var(--ink-muted,#777);font-weight:900;font-size:18px;}
  details.faq-item[open] summary::after{content:"\2212";}
  details.faq-item[open] p{margin-top:10px;}