:root {
  --bg: #111315;
  --surface: #181b1e;
  --surface-2: #202428;
  --soft: #171a1d;
  --text: #f2f3f3;
  --muted: #a9b0b5;
  --line: #343a3f;
  --accent: #9fc9ba;
  --accent-strong: #c1e4d8;
  --focus: #d8f3ea;
  --max: 1180px;
  --radius: 12px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}
a { color: inherit; }
.shell { width: min(calc(100% - 40px), var(--max)); margin: 0 auto; }
.narrow { max-width: 760px; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(17,19,21,.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}
.header-inner {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  text-decoration: none;
  font-weight: 750;
}
nav {
  display: flex;
  gap: 22px;
  flex-wrap: wrap;
}
nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: .93rem;
}
nav a:hover, nav a:focus { color: var(--text); }

.hero { padding: 110px 0 100px; max-width: 960px; }
.eyebrow {
  margin: 0 0 12px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .09em;
  font-size: .77rem;
  font-weight: 800;
}
h1, h2, h3 { line-height: 1.14; letter-spacing: -.025em; }
h1 { margin: 0; max-width: 900px; font-size: clamp(2.15rem, 4.5vw, 4.2rem); font-weight: 720; }
.hero-copy { max-width: 760px; margin: 28px 0 30px; font-size: 1.18rem; color: #c7ccd0; }
.button, button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--text);
  background: var(--accent-strong);
  color: #101313;
  padding: 13px 18px;
  border-radius: 7px;
  font: inherit;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}
.button:hover, button:hover { opacity: .86; }

.section { padding: 90px 0; }
.section-soft { background: var(--soft); }
.section-heading { max-width: 760px; margin-bottom: 40px; }
.section-heading h2, #about h2, #contact h2 {
  margin: 0 0 14px;
  font-size: clamp(2rem, 4vw, 3.4rem);
}
.section-heading > p:last-child { color: var(--muted); font-size: 1.05rem; }

.accordion-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0,1fr));
  gap: 14px;
  align-items: start;
}
.problem-card, .example-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  overflow: clip;
}
summary {
  list-style: none;
  cursor: pointer;
}
summary::-webkit-details-marker { display: none; }
.problem-card summary, .example-card summary {
  min-height: 128px;
  padding: 22px;
  display: flex;
  justify-content: space-between;
  gap: 20px;
}
.problem-card summary strong, .example-card summary strong {
  display: block;
  font-size: 1.08rem;
  line-height: 1.3;
}
.problem-card summary small, .example-card summary small {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  font-size: .9rem;
  line-height: 1.45;
}
.plus {
  flex: none;
  color: var(--muted);
  font-size: 1.5rem;
  line-height: 1;
  transition: transform .2s ease;
}
details[open] .plus { transform: rotate(45deg); }
.drawer {
  padding: 0 22px 24px;
  border-top: 1px solid var(--line);
}
.drawer p { margin: 18px 0 0; }
.drawer h3 {
  margin: 24px 0 0;
  font-size: .95rem;
  text-transform: uppercase;
  letter-spacing: .06em;
}
.pullquote {
  font-size: 1.16rem;
  font-weight: 720;
}

.approach-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0,1fr));
  gap: 22px 38px;
}
.approach-grid article {
  border-top: 1px solid var(--line);
  padding-top: 18px;
}
.approach-grid h3 { margin: 0 0 8px; font-size: 1.05rem; }
.approach-grid p { margin: 0; color: #c1c6ca; }

.example-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0,1fr));
  gap: 16px;
  align-items: start;
}
.example-card summary { min-height: 170px; }
.example-card summary small {
  text-transform: uppercase;
  letter-spacing: .06em;
  font-size: .72rem;
  color: var(--accent);
  font-weight: 800;
  margin: 0 0 10px;
}

#about p { font-size: 1.08rem; color: #d2d6d9; }

.contact-wrap {
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: 80px;
  align-items: start;
}
.contact-form {
  display: grid;
  gap: 18px;
}
.contact-form label {
  display: grid;
  gap: 7px;
  font-size: .9rem;
  font-weight: 700;
}
input, textarea {
  width: 100%;
  border: 1px solid #4b5359;
  border-radius: 7px;
  padding: 12px 13px;
  font: inherit;
  background: var(--surface);
}
input:focus, textarea:focus {
  outline: 2px solid rgba(159,201,186,.25);
  border-color: var(--accent);
}
textarea { resize: vertical; }
.hp-field {
  position: absolute !important;
  left: -10000px !important;
  width: 1px !important;
  height: 1px !important;
  overflow: hidden !important;
}
.form-note { margin: 0; color: var(--muted); font-size: .84rem; }

footer {
  border-top: 1px solid var(--line);
  padding: 30px 0 40px;
  color: var(--muted);
  font-size: .9rem;
}

@media (max-width: 900px) {
  .example-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .contact-wrap { grid-template-columns: 1fr; gap: 42px; }
}

@media (max-width: 700px) {
  .header-inner { align-items: flex-start; padding: 18px 0; }
  nav { display: none; }
  .hero { padding: 72px 0 68px; }
  .section { padding: 68px 0; }
  .accordion-grid, .approach-grid, .example-grid { grid-template-columns: 1fr; }
  .problem-card summary, .example-card summary { min-height: 0; }
  .shell { width: min(calc(100% - 28px), var(--max)); }
}



/* Dark-mode usability refinements */
body {
  text-rendering: optimizeLegibility;
}

.site-header {
  box-shadow: 0 1px 0 rgba(255,255,255,.02);
}

.hero {
  padding-top: 96px;
}

.hero h1 {
  max-width: 980px;
}

.section-heading p,
.hero-copy {
  max-width: 720px;
}

.interaction-hint {
  margin: -18px 0 24px;
  color: var(--muted);
  font-size: .92rem;
}
.interaction-hint span {
  display: inline-grid;
  place-items: center;
  width: 1.35rem;
  height: 1.35rem;
  margin-right: .35rem;
  border: 1px solid var(--line);
  border-radius: 50%;
  color: var(--accent-strong);
  font-weight: 800;
}

.problem-card,
.example-card {
  background: var(--surface);
  border-color: var(--line);
  transition: border-color .18s ease, transform .18s ease, background .18s ease;
}
.problem-card:hover,
.example-card:hover {
  border-color: #556068;
  background: #1b1f22;
}
.problem-card[open],
.example-card[open] {
  border-color: #5f776e;
  background: var(--surface-2);
}

.problem-card summary,
.example-card summary {
  position: relative;
  outline: none;
}
.problem-card summary:focus-visible,
.example-card summary:focus-visible {
  box-shadow: inset 0 0 0 2px var(--focus);
}

.problem-card summary strong,
.example-card summary strong {
  color: var(--text);
}
.problem-card summary small,
.example-card summary small {
  color: var(--muted);
}

.plus {
  display: inline-grid;
  place-items: center;
  width: 1.8rem;
  height: 1.8rem;
  border: 1px solid var(--line);
  border-radius: 50%;
  color: var(--accent-strong);
  font-size: 1.1rem;
  font-weight: 700;
}

.drawer {
  background: rgba(0,0,0,.09);
  border-top-color: var(--line);
}
.drawer h3 {
  color: var(--accent-strong);
}
.drawer p {
  color: #d8dcdf;
}

.pullquote {
  color: #ffffff !important;
  border-left: 3px solid var(--accent);
  padding-left: 16px;
}

.section-soft {
  background: var(--soft);
  border-top: 1px solid #1f2427;
  border-bottom: 1px solid #1f2427;
}

.approach-grid article {
  border-top-color: var(--line);
}
.approach-grid h3 {
  color: var(--text);
}
.approach-grid p {
  color: #bdc4c8;
}

#about p {
  color: #cdd2d5;
}

.contact-form {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
}
input,
textarea {
  background: #101315;
  color: var(--text);
  border-color: #485057;
}
input::placeholder,
textarea::placeholder {
  color: #777f85;
}
button,
.button {
  border-color: var(--accent-strong);
  background: var(--accent-strong);
  color: #0f1213;
}
button:hover,
.button:hover {
  opacity: 1;
  background: #d1eee4;
}

footer {
  background: #0c0e10;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    transition-duration: .001ms !important;
    animation-duration: .001ms !important;
  }
}
.optional { color: var(--muted); font-weight: 500; font-size: .82em; }


/* Mobile density pass */
@media (max-width: 700px) {
  .site-header {
    position: static;
  }

  .header-inner {
    min-height: 54px;
    padding: 14px 0;
  }

  .brand {
    font-size: .95rem;
  }

  .hero {
    padding: 52px 0 48px;
  }

  h1 {
    font-size: clamp(1.85rem, 9vw, 2.7rem);
    line-height: 1.05;
    letter-spacing: -.035em;
  }

  .hero-copy {
    margin: 20px 0 24px;
    font-size: 1.02rem;
    line-height: 1.5;
  }

  .button {
    width: 100%;
    text-align: center;
    padding: 12px 14px;
  }

  .section {
    padding: 52px 0;
  }

  .section-heading {
    margin-bottom: 26px;
  }

  .section-heading h2,
  #about h2,
  #contact h2 {
    font-size: clamp(1.75rem, 8vw, 2.45rem);
    margin-bottom: 10px;
  }

  .section-heading > p:last-child {
    font-size: .98rem;
  }

  .interaction-hint {
    margin: -10px 0 18px;
    font-size: .87rem;
    line-height: 1.45;
  }

  .accordion-grid,
  .example-grid {
    gap: 10px;
  }

  .problem-card summary,
  .example-card summary {
    padding: 17px 16px;
  }

  .problem-card summary strong,
  .example-card summary strong {
    font-size: 1rem;
  }

  .problem-card summary small,
  .example-card summary small {
    margin-top: 6px;
    font-size: .84rem;
  }

  .plus {
    width: 1.6rem;
    height: 1.6rem;
    font-size: 1rem;
  }

  .drawer {
    padding: 0 16px 18px;
  }

  .drawer p {
    margin-top: 14px;
    font-size: .96rem;
    line-height: 1.5;
  }

  .drawer h3 {
    margin-top: 20px;
    font-size: .82rem;
  }

  .pullquote {
    font-size: 1.05rem;
    padding-left: 12px;
  }

  .approach-grid {
    gap: 16px;
  }

  .approach-grid article {
    padding-top: 14px;
  }

  .approach-grid h3 {
    font-size: 1rem;
  }

  .approach-grid p {
    font-size: .94rem;
  }

  #about p {
    font-size: 1rem;
    line-height: 1.55;
  }

  .contact-wrap {
    gap: 28px;
  }

  .contact-form {
    padding: 18px;
    gap: 14px;
  }

  input,
  textarea {
    padding: 11px 12px;
  }

  footer {
    padding: 22px 0 28px;
  }
}

/* Extra-small phones */
@media (max-width: 420px) {
  .shell {
    width: min(calc(100% - 22px), var(--max));
  }

  .hero {
    padding-top: 44px;
  }

  h1 {
    font-size: clamp(1.75rem, 8.5vw, 2.3rem);
  }

  .eyebrow {
    font-size: .7rem;
  }

  .problem-card summary,
  .example-card summary {
    padding: 15px 14px;
  }

  .drawer {
    padding: 0 14px 16px;
  }
}

button:disabled {
  opacity: .65;
  cursor: wait;
}
.form-note:empty {
  display: none;
}