:root {
    --paper: #F7F8F5;
    --surface: #FFFFFF;
    --ink: #1B2823;
    --muted: #66756D;
    --spruce: #2F5D4A;
    --spruce-soft: #E7EFEA;
    --amber: #C07A22;
    --line: #DBE2DB;
    --phone-frame: #22312B;
    --shadow: 0 24px 60px -30px rgba(27, 40, 35, 0.35);
  }
  @media (prefers-color-scheme: dark) {
    :root {
      --paper: #0F1613;
      --surface: #17211C;
      --ink: #E4EAE5;
      --muted: #93A199;
      --spruce: #7FB89E;
      --spruce-soft: #1C2A23;
      --amber: #D99A4E;
      --line: #26332B;
      --phone-frame: #060A08;
      --shadow: 0 24px 60px -30px rgba(0, 0, 0, 0.7);
    }
  }
  :root[data-theme="light"] {
    --paper: #F7F8F5;
    --surface: #FFFFFF;
    --ink: #1B2823;
    --muted: #66756D;
    --spruce: #2F5D4A;
    --spruce-soft: #E7EFEA;
    --amber: #C07A22;
    --line: #DBE2DB;
    --phone-frame: #22312B;
    --shadow: 0 24px 60px -30px rgba(27, 40, 35, 0.35);
  }
  :root[data-theme="dark"] {
    --paper: #0F1613;
    --surface: #17211C;
    --ink: #E4EAE5;
    --muted: #93A199;
    --spruce: #7FB89E;
    --spruce-soft: #1C2A23;
    --amber: #D99A4E;
    --line: #26332B;
    --phone-frame: #060A08;
    --shadow: 0 24px 60px -30px rgba(0, 0, 0, 0.7);
  }

  * { box-sizing: border-box; }
  html { scroll-behavior: smooth; }
  @media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .wave span { animation: none !important; }
  }
  body {
    margin: 0;
    background: var(--paper);
    color: var(--ink);
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    font-size: 16.5px;
    line-height: 1.65;
    -webkit-font-smoothing: antialiased;
  }
  .serif {
    font-family: ui-serif, "New York", "Iowan Old Style", "Palatino", Georgia, serif;
  }
  .mono {
    font-family: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
  }

  .wrap { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

  /* ---------- header ---------- */
  header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 22px 0;
  }
  .wordmark {
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 15px; letter-spacing: 0.04em;
    color: var(--ink); text-decoration: none;
  }
  .wordmark b { color: var(--spruce); font-weight: 700; }
  .header-cta {
    font-size: 14px; font-weight: 600; text-decoration: none;
    color: var(--spruce);
    border: 1px solid var(--spruce);
    border-radius: 999px; padding: 7px 16px;
  }
  .header-cta:hover, .header-cta:focus-visible { background: var(--spruce-soft); }

  /* ---------- hero ---------- */
  .hero {
    display: grid; grid-template-columns: 1.05fr 0.95fr;
    gap: 48px; align-items: center;
    padding: 56px 0 72px;
  }
  .eyebrow {
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 12px; font-weight: 600;
    letter-spacing: 0.14em; text-transform: uppercase;
    color: var(--amber);
    margin: 0 0 18px;
  }
  h1 {
    font-family: ui-serif, "New York", "Iowan Old Style", Georgia, serif;
    font-size: clamp(32px, 4.6vw, 50px);
    line-height: 1.12; font-weight: 600;
    letter-spacing: -0.01em;
    text-wrap: balance;
    margin: 0 0 22px;
  }
  .hero p.lede {
    font-size: 18px; color: var(--muted);
    max-width: 34em; margin: 0 0 30px;
  }
  .hero p.lede strong { color: var(--ink); font-weight: 600; }
  .cta-row { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
  .btn-primary {
    display: inline-block;
    background: var(--spruce); color: var(--paper);
    font-weight: 600; font-size: 16px;
    text-decoration: none;
    padding: 13px 26px; border-radius: 10px;
  }
  .btn-primary:hover { filter: brightness(1.08); }
  .btn-primary:focus-visible, .header-cta:focus-visible, a:focus-visible, button:focus-visible {
    outline: 2px solid var(--amber); outline-offset: 3px;
  }
  .cta-note { font-size: 14px; color: var(--muted); margin: 14px 0 0; }

  /* ---------- phone in its boundary ---------- */
  .boundary {
    position: relative;
    border: 1.5px dashed color-mix(in srgb, var(--spruce) 55%, transparent);
    border-radius: 34px;
    padding: 34px 30px 26px;
    display: flex; flex-direction: column; align-items: center; gap: 14px;
  }
  .boundary-label {
    position: absolute; top: -11px; left: 50%; transform: translateX(-50%);
    background: var(--paper);
    padding: 0 12px;
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 11px; font-weight: 600;
    letter-spacing: 0.12em; text-transform: uppercase;
    color: var(--spruce); white-space: nowrap;
  }
  .phone {
    width: min(290px, 78vw);
    background: var(--surface);
    border: 7px solid var(--phone-frame);
    border-radius: 42px;
    padding: 18px 16px 22px;
    box-shadow: var(--shadow);
  }
  .phone .notch {
    width: 86px; height: 20px;
    background: var(--phone-frame);
    border-radius: 999px;
    margin: 0 auto 16px;
  }
  .chip {
    display: inline-block;
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 10.5px; font-weight: 600;
    letter-spacing: 0.1em; text-transform: uppercase;
    color: var(--spruce);
    background: var(--spruce-soft);
    border-radius: 999px;
    padding: 4px 10px;
    margin-bottom: 14px;
  }
  .bubble {
    font-size: 14px; line-height: 1.5;
    border-radius: 14px;
    padding: 10px 13px;
    margin-bottom: 10px;
    max-width: 92%;
  }
  .bubble.ouma {
    background: var(--spruce-soft);
    border-bottom-left-radius: 4px;
  }
  .bubble.learner {
    background: color-mix(in srgb, var(--amber) 14%, var(--surface));
    border-bottom-right-radius: 4px;
    margin-left: auto;
  }
  .bubble .who {
    display: block;
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 10px; letter-spacing: 0.1em; text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 3px;
  }
  .wave {
    display: flex; align-items: center; gap: 3px;
    height: 22px; padding: 2px 0;
  }
  .wave span {
    width: 4px; border-radius: 2px;
    background: var(--amber);
    animation: pulse 1.1s ease-in-out infinite;
  }
  .wave span:nth-child(1) { height: 8px;  animation-delay: 0s; }
  .wave span:nth-child(2) { height: 16px; animation-delay: 0.12s; }
  .wave span:nth-child(3) { height: 21px; animation-delay: 0.24s; }
  .wave span:nth-child(4) { height: 12px; animation-delay: 0.36s; }
  .wave span:nth-child(5) { height: 18px; animation-delay: 0.48s; }
  .wave span:nth-child(6) { height: 9px;  animation-delay: 0.6s; }
  .wave span:nth-child(7) { height: 14px; animation-delay: 0.72s; }
  @keyframes pulse {
    0%, 100% { transform: scaleY(0.55); }
    50% { transform: scaleY(1); }
  }
  .airplane {
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 11.5px; color: var(--muted);
    display: flex; align-items: center; gap: 6px;
  }
  .airplane .dot { color: var(--spruce); font-weight: 700; }
  .boundary-caption {
    font-size: 13.5px; color: var(--muted);
    text-align: center; max-width: 30em;
    margin: 16px auto 0;
  }

  /* ---------- sections ---------- */
  section { border-top: 1px solid var(--line); padding: 64px 0; }
  .section-eyebrow {
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 12px; font-weight: 600;
    letter-spacing: 0.14em; text-transform: uppercase;
    color: var(--amber); margin: 0 0 14px;
  }
  h2 {
    font-family: ui-serif, "New York", "Iowan Old Style", Georgia, serif;
    font-size: clamp(26px, 3.4vw, 36px);
    line-height: 1.18; font-weight: 600;
    letter-spacing: -0.005em;
    text-wrap: balance;
    margin: 0 0 18px;
  }
  .measure { max-width: 42em; }
  .measure p { margin: 0 0 16px; }
  .muted { color: var(--muted); }

  /* pillars */
  .pillars {
    display: grid; grid-template-columns: repeat(3, 1fr);
    gap: 28px; margin-top: 38px;
  }
  .pillar h3 {
    font-family: ui-serif, "New York", "Iowan Old Style", Georgia, serif;
    font-size: 21px; font-weight: 600; margin: 0 0 10px;
  }
  .pillar p { font-size: 15.5px; color: var(--muted); margin: 0; }
  .pillar .tick {
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    display: inline-block;
    font-size: 11px; font-weight: 600; letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--spruce);
    margin-bottom: 12px;
  }

  /* loop */
  .loop { counter-reset: step; margin-top: 38px; display: grid; gap: 0; }
  .loop-step {
    display: grid; grid-template-columns: 64px 1fr;
    gap: 20px; padding: 22px 0;
    border-top: 1px solid var(--line);
  }
  .loop-step:first-child { border-top: none; }
  .loop-step .num {
    font-family: ui-serif, "New York", Georgia, serif;
    font-size: 30px; color: var(--amber); line-height: 1.1;
    font-variant-numeric: tabular-nums;
  }
  .loop-step h3 { font-size: 17px; font-weight: 650; margin: 2px 0 6px; }
  .loop-step p { font-size: 15.5px; color: var(--muted); margin: 0; max-width: 44em; }

  /* audience */
  .aud-grid {
    display: grid; grid-template-columns: repeat(2, 1fr);
    gap: 26px; margin-top: 38px;
  }
  .aud {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 26px 26px 24px;
  }
  .aud h3 {
    font-family: ui-serif, "New York", "Iowan Old Style", Georgia, serif;
    font-size: 20px; font-weight: 600; margin: 0 0 8px;
  }
  .aud p { font-size: 15px; color: var(--muted); margin: 0; }

  /* compare table */
  .compare-wrap { overflow-x: auto; margin-top: 34px; }
  table.compare {
    border-collapse: collapse; width: 100%;
    font-size: 15px; min-width: 520px;
  }
  table.compare th, table.compare td {
    text-align: left; padding: 13px 16px;
    border-top: 1px solid var(--line);
  }
  table.compare thead th {
    border-top: none;
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 11.5px; letter-spacing: 0.1em; text-transform: uppercase;
    color: var(--muted); font-weight: 600;
  }
  table.compare td.yes { color: var(--spruce); font-weight: 600; }
  table.compare td.no { color: var(--muted); }
  table.compare th[scope="row"] { font-weight: 500; }

  /* specs */
  .specs {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 28px 30px;
    margin-top: 34px;
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 14px; line-height: 2.05;
  }
  .specs .k { color: var(--muted); }
  .specs .v { color: var(--ink); font-weight: 600; }
  .specs-note { font-size: 14px; color: var(--muted); margin-top: 16px; max-width: 40em; }

  /* faq */
  .faq { margin-top: 30px; display: grid; gap: 26px; }
  .faq h3 { font-size: 16.5px; font-weight: 650; margin: 0 0 6px; }
  .faq p { font-size: 15.5px; color: var(--muted); margin: 0; max-width: 44em; }

  /* final cta */
  .final {
    text-align: center;
    padding: 84px 0 90px;
  }
  .final h2 {
    font-size: clamp(32px, 4.4vw, 46px);
    margin-bottom: 12px;
  }
  .final .sub { font-size: 18px; color: var(--muted); margin: 0 0 32px; }
  .email-row {
    display: flex; align-items: center; justify-content: center;
    gap: 12px; flex-wrap: wrap; margin-top: 22px;
  }
  .email-pill {
    font-family: ui-monospace, "SF Mono", Menlo, monospace;
    font-size: 14px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 9px 18px;
  }
  button.copy {
    font: inherit; font-size: 13.5px; font-weight: 600;
    color: var(--spruce);
    background: none; border: 1px solid var(--spruce);
    border-radius: 999px;
    padding: 8px 16px;
    cursor: pointer;
  }
  button.copy:hover { background: var(--spruce-soft); }

  footer {
    border-top: 1px solid var(--line);
    padding: 30px 0 44px;
    display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap;
    font-size: 13.5px; color: var(--muted);
  }
  footer a { color: var(--spruce); text-decoration: none; }
  footer a:hover { text-decoration: underline; }

  @media (max-width: 820px) {
    .hero { grid-template-columns: 1fr; padding-top: 28px; gap: 44px; }
    .pillars { grid-template-columns: 1fr; }
    .aud-grid { grid-template-columns: 1fr; }
    section { padding: 52px 0; }
  }

/* ---------- multi-page additions ---------- */
.nav { display: flex; align-items: center; gap: 22px; flex-wrap: wrap; }
.nav a.navlink {
  font-size: 14px; font-weight: 500;
  color: var(--muted); text-decoration: none;
}
.nav a.navlink:hover { color: var(--spruce); }
.nav a.navlink[aria-current="page"] { color: var(--spruce); font-weight: 650; }

.page-head { padding: 44px 0 10px; }
.page-head h1 {
  font-family: ui-serif, "New York", "Iowan Old Style", Georgia, serif;
  font-size: clamp(30px, 4vw, 42px);
  line-height: 1.14; font-weight: 600;
  letter-spacing: -0.01em; text-wrap: balance;
  margin: 0 0 10px;
}
.page-head .sub { font-size: 17px; color: var(--muted); max-width: 40em; margin: 0; }

.prose { max-width: 46em; padding-bottom: 72px; }
.prose h2 {
  font-family: ui-serif, "New York", "Iowan Old Style", Georgia, serif;
  font-size: 23px; font-weight: 600;
  margin: 40px 0 12px; text-wrap: balance;
}
.prose p { margin: 0 0 15px; }
.prose ul { margin: 0 0 15px; padding-left: 22px; }
.prose li { margin-bottom: 8px; }
.prose .updated {
  font-family: ui-monospace, "SF Mono", Menlo, monospace;
  font-size: 13px; color: var(--muted);
}
.draft-banner {
  border: 1.5px dashed var(--amber);
  border-radius: 12px;
  padding: 14px 18px;
  font-size: 14.5px;
  color: var(--ink);
  background: color-mix(in srgb, var(--amber) 7%, var(--paper));
  margin: 26px 0 34px;
  max-width: 46em;
}
.draft-banner b { color: var(--amber); }

footer .footnav { display: flex; gap: 18px; flex-wrap: wrap; }