.about-scroll-space {
  position: relative;
  height: 320vh;
  z-index: 1;
}

.about-sticky-stage {
  position: sticky;
  top: var(--header-height);
  width: 100%;
  max-width: var(--max-width-content);
  height: calc(100vh - var(--header-height));
  height: calc(100dvh - var(--header-height));
  margin: 0 auto;
  display: flex;
  align-items: center;
  padding: 0 clamp(1.5rem, 4vw, 3.5rem);
}

.stack-scene {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(230px, 300px);
  gap: clamp(1.5rem, 3vw, 3rem);
  align-items: center;
  width: 100%;
}

.about-cards-stack {
  --cards-gap: clamp(14px, 1.6vw, 24px);
  position: relative;
  width: 100%;
  padding: 1.75rem 0;
  overflow: hidden;
  isolation: isolate;
  -webkit-mask-image: linear-gradient(90deg, transparent 0, #000 4%, #000 96%, transparent 100%);
  mask-image: linear-gradient(90deg, transparent 0, #000 4%, #000 96%, transparent 100%);
}

.cards-track {
  display: flex;
  align-items: stretch;
  gap: var(--cards-gap);
  width: max-content;
  transform: translate3d(var(--rail-x, 0px), 0, 0);
  will-change: transform;
}

.cards-track .card {
  position: relative;
  flex: 0 0 var(--card-w, 300px);
  width: var(--card-w, 300px);
  min-height: clamp(290px, 38vh, 350px);
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(circle at 92% 4%, rgba(98, 220, 228, 0.1) 0%, transparent 38%),
    linear-gradient(165deg, rgba(4, 67, 86, 0.98) 0%, rgba(1, 43, 58, 1) 100%);
  border-radius: var(--radius-lg);
  box-shadow:
    0 22px 54px -20px rgba(0, 0, 0, 0.72),
    0 0 0 1px rgba(0, 200, 196, 0.12);
  overflow: hidden;
  transform: translate3d(0, var(--card-y, 0px), 0) scale(var(--card-scale, 1));
  opacity: var(--card-opacity, 1);
  z-index: var(--card-z, 1);
  will-change: transform, opacity;
  transition: box-shadow 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.cards-track .card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 55%, rgba(0, 8, 14, 0.2) 100%);
  pointer-events: none;
}

.cards-track .card.is-active {
  box-shadow:
    0 30px 68px -22px rgba(0, 0, 0, 0.82),
    0 0 0 1px rgba(98, 220, 228, 0.52);
}

.card-accent {
  height: 3px;
  width: 100%;
  flex-shrink: 0;
}

.card[data-step="1"] .card-accent {
  background: linear-gradient(90deg, var(--color-turquoise), var(--color-aqua));
}

.card[data-step="2"] .card-accent {
  background: linear-gradient(90deg, var(--color-aqua), var(--color-sky));
}

.card[data-step="3"] .card-accent {
  background: linear-gradient(90deg, var(--color-sky), var(--color-aqua));
}

.card[data-step="4"] .card-accent {
  background: linear-gradient(90deg, var(--color-sky), var(--color-amber));
}

.card[data-step="5"] .card-accent {
  background: linear-gradient(90deg, var(--color-aqua), var(--color-amber));
}

.card[data-step="6"] .card-accent {
  background: linear-gradient(90deg, var(--color-amber), var(--color-aqua));
}

.card-header {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.55rem;
  padding: clamp(1rem, 1.8vw, 1.45rem) clamp(1.05rem, 1.8vw, 1.5rem) 0;
  margin-bottom: 0.7rem;
}

.card-number {
  display: inline-flex;
  padding: 0.2rem 0.55rem;
  border: 1px solid rgba(98, 220, 228, 0.26);
  border-radius: var(--radius-pill);
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  color: var(--color-aqua);
  line-height: 1.2;
}

.card-title {
  font-family: var(--font-display);
  font-size: clamp(1.08rem, 0.98rem + 0.38vw, 1.35rem);
  font-weight: 650;
  color: var(--color-cream);
  margin: 0;
  line-height: 1.25;
  letter-spacing: -0.02em;
  text-wrap: balance;
}

.card-text {
  position: relative;
  z-index: 1;
  font-size: clamp(0.86rem, 0.82rem + 0.12vw, 0.94rem);
  line-height: 1.62;
  color: var(--color-cream-soft);
  padding: 0 clamp(1.05rem, 1.8vw, 1.5rem) clamp(1.15rem, 2vw, 1.6rem);
}

.highlight {
  background: rgba(0, 200, 196, 0.14);
  padding: 0.08em 0.32em;
  border-radius: 3px;
  color: var(--color-aqua);
  font-weight: 500;
}

.stack-panel {
  position: relative;
  min-height: clamp(290px, 38vh, 350px);
  display: flex;
  align-items: center;
}

.stack-panel__chapter {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
  padding-left: clamp(1rem, 2vw, 2rem);
  border-left: 1px solid rgba(98, 220, 228, 0.18);
  transition:
    opacity 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.4s cubic-bezier(0.16, 1, 0.3, 1),
    visibility 0.4s;
}

.stack-panel.is-complete .stack-panel__chapter {
  opacity: 0;
  visibility: hidden;
  transform: translateY(-12px);
}

.stack-panel__count {
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 1.8rem + 2.2vw, 4rem);
  font-weight: 800;
  line-height: 0.82;
  letter-spacing: -0.05em;
  color: rgba(247, 239, 226, 0.2);
}

.stack-panel__count-total {
  font-size: 0.28em;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--color-cream-dim);
}

.stack-panel__eyebrow {
  display: block;
  margin-bottom: 0.35rem;
  font-family: var(--font-body);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-aqua);
}

.stack-panel__title {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 1.2rem + 2vw, 2.9rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.04em;
  color: var(--color-cream);
  margin: 0;
  text-wrap: balance;
}

.stack-panel__text {
  margin-top: 0.65rem;
  max-width: 28ch;
  font-size: clamp(0.88rem, 0.84rem + 0.12vw, 0.98rem);
  line-height: 1.55;
  color: var(--color-cream-muted);
}

.stack-panel__progress {
  position: relative;
  width: 2px;
  height: clamp(64px, 10vh, 100px);
  background: rgba(247, 239, 226, 0.1);
  overflow: hidden;
}

.stack-panel__progress-fill {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, var(--color-aqua), var(--color-amber));
  transform: scaleY(var(--panel-progress, 0));
  transform-origin: top center;
}

.stack-outro {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  padding-left: clamp(1rem, 2vw, 2rem);
  opacity: 0;
  visibility: hidden;
  transform: translateX(26px);
  pointer-events: none;
  transition:
    opacity 0.55s cubic-bezier(0.16, 1, 0.3, 1),
    transform 0.55s cubic-bezier(0.16, 1, 0.3, 1),
    visibility 0.55s;
}

.stack-panel.is-complete .stack-outro {
  opacity: 1;
  visibility: visible;
  transform: translateX(0);
  pointer-events: auto;
}

.stack-outro .about-section-tag {
  margin-bottom: 1rem;
  padding: 0.38rem 0.95rem;
  color: var(--color-primary-dark);
  font-weight: 700;
  background-color: var(--color-aqua);
  background-image: linear-gradient(135deg, var(--color-aqua), var(--color-turquoise));
  border-color: transparent;
  box-shadow: 0 8px 20px -10px rgba(0, 200, 196, 0.55);
}

.stack-outro__heading {
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 1.1rem + 2vw, 2.55rem);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.04em;
  color: #ffffff;
  margin-bottom: 0.85rem;
  text-wrap: balance;
}

.stack-outro__sub {
  font-size: clamp(0.86rem, 0.82rem + 0.12vw, 0.95rem);
  line-height: 1.58;
  color: rgba(255, 255, 255, 0.78);
  max-width: 30ch;
  text-wrap: pretty;
}

.stack-outro__cta {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1.2rem;
  padding: 0.65rem 1.05rem;
  border: 1px solid rgba(252, 174, 38, 0.55);
  border-radius: var(--radius-pill);
  color: var(--color-amber);
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  transition:
    background-color var(--transition-fast),
    border-color var(--transition-fast),
    color var(--transition-fast);
}

.stack-outro__cta:hover,
.stack-outro__cta:focus-visible {
  background-color: var(--color-amber);
  border-color: var(--color-amber);
  color: var(--color-primary-dark);
}

.stack-outro__cta:focus-visible {
  outline: 2px solid var(--color-cream);
  outline-offset: 3px;
}

.about-section.is-static .about-scroll-space {
  height: auto !important;
}

.about-section.is-static .about-sticky-stage {
  position: relative;
  top: auto;
  height: auto;
  display: block;
  padding-top: 1rem;
  padding-bottom: clamp(160px, 22vw, 240px);
}

.about-section.is-static .stack-scene {
  display: block;
}

.about-section.is-static .about-cards-stack {
  overflow: visible;
  padding: 0;
  -webkit-mask-image: none;
  mask-image: none;
}

.about-section.is-static .cards-track {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--cards-gap);
  width: 100%;
  transform: none !important;
}

.about-section.is-static .cards-track .card {
  width: 100%;
  min-height: 0;
  transform: none !important;
  opacity: 1 !important;
}

.about-section.is-static .stack-panel {
  display: block;
  min-height: 0;
}

.about-section.is-static .stack-panel__chapter {
  display: none;
}

.about-section.is-static .stack-outro {
  position: relative;
  z-index: 10;
  max-width: 560px;
  margin: 2.5rem auto 0;
  padding: 0;
  align-items: center;
  text-align: center;
  opacity: 1;
  visibility: visible;
  transform: none;
  pointer-events: auto;
}

.about-section.is-static .stack-outro__sub {
  margin-left: auto;
  margin-right: auto;
}

@media (max-width: 1023px) {
  .stack-scene {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }

  .about-sticky-stage {
    padding-left: clamp(1rem, 4vw, 2rem);
    padding-right: clamp(1rem, 4vw, 2rem);
  }

  .about-cards-stack {
    padding-top: 1rem;
    padding-bottom: 1rem;
  }

  .stack-panel {
    min-height: 180px;
  }

  .stack-panel__chapter {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 1.25rem;
    padding-top: 1.1rem;
    padding-left: 0;
    border-left: 0;
    border-top: 1px solid rgba(98, 220, 228, 0.18);
  }

  .stack-panel__count {
    font-size: 2.2rem;
  }

  .stack-panel__text {
    max-width: 46ch;
  }

  .stack-panel__progress {
    position: absolute;
    top: 1.1rem;
    right: 0;
    bottom: 0;
    width: 2px;
    height: auto;
  }

  .stack-outro {
    justify-content: flex-start;
    padding-top: 1.1rem;
    padding-left: 0;
  }

  .stack-outro__heading {
    font-size: clamp(1.6rem, 4vw, 2.35rem);
  }

  .stack-outro__sub {
    max-width: 52ch;
  }

  .about-section.is-static .cards-track {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 639px) {
  .about-sticky-stage {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  .about-cards-stack {
    padding-top: 0.5rem;
    padding-bottom: 0.5rem;
  }

  .stack-panel {
    min-height: 205px;
  }

  .stack-panel__chapter {
    grid-template-columns: 1fr;
    gap: 0.55rem;
  }

  .stack-panel__count {
    font-size: 1.55rem;
  }

  .stack-panel__title {
    font-size: 1.5rem;
  }

  .stack-panel__text {
    max-width: 100%;
    font-size: 0.84rem;
  }

  .stack-panel__progress {
    display: none;
  }

  .stack-outro__heading {
    font-size: 1.45rem;
  }

  .stack-outro__sub {
    font-size: 0.84rem;
  }

  .stack-outro__cta {
    margin-top: 0.9rem;
  }

  .about-section.is-static .cards-track {
    grid-template-columns: 1fr;
  }
}

@media (max-height: 700px) and (min-width: 1024px) {
  .cards-track .card,
  .stack-panel {
    min-height: clamp(270px, 58vh, 340px);
  }

  .card-header {
    padding-top: 1rem;
  }

  .stack-panel__count {
    font-size: 2.6rem;
  }
}

.stack-scene.is-complete .about-cards-stack {
  opacity: 0.68;
  transition: opacity 0.55s cubic-bezier(0.16, 1, 0.3, 1);
}