.cube-section {
  --cube-section-columns: minmax(7rem, .28fr) minmax(0, 1.72fr);
  --cube-section-gap: clamp(2rem, 5.5vw, 7rem);

  position: relative;
  z-index: 1;
  padding-block: clamp(6rem, 9vw, 9rem);
  scroll-margin-top: var(--cube-header);
  border-bottom: 1px solid var(--line);
  background: var(--bg);
}

.cube-section__grid,
.cube-hardware > .cube-shell,
.cube-physical-design > .cube-shell {
  display: grid;
  grid-template-columns: var(--cube-section-columns);
  align-items: start;
  column-gap: var(--cube-section-gap);
}

.cube-section__grid {
  row-gap: var(--cube-section-gap);
}

.cube-section__rail {
  display: flex;
  flex-direction: column;
  gap: .8rem;
}

.cube-section__index,
.cube-section__eyebrow {
  margin: 0;
  text-transform: uppercase;
  font-family: var(--project-font-mono);
  font-size: var(--project-text-label);
  font-weight: var(--project-weight-medium);
  line-height: var(--project-leading-tight);
  letter-spacing: var(--project-tracking-label);
}

.cube-section__index {
  color: var(--muted);
}

.cube-section__eyebrow {
  color: var(--accent);
}

.cube-section__heading {
  max-width: 14ch;
  margin: 0;
  text-wrap: balance;
  font-family: var(--project-font-body);
  font-size: var(--project-text-section);
  font-weight: var(--project-weight-semibold);
  line-height: var(--project-leading-heading);
  letter-spacing: var(--project-tracking-heading);
}

.cube-introduction__content { min-width: 0; }
.cube-introduction__content > .cube-section__heading { max-width: none; }

.cube-introduction__features {
  margin: clamp(1.75rem, 3vw, 2.75rem) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  align-items: start;
  gap: 1rem;
  list-style: none;
}

.cube-introduction__card {
  min-width: 0;
  border-radius: .875rem;
  background: var(--surface-raised);
}

.cube-introduction__details.cube-disclosure {
  border: 0;
}

.cube-introduction__details.cube-disclosure > summary {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: .875rem 1rem;
  min-height: 56px;
  padding: clamp(1.125rem, 1.75vw, 1.5rem);
  border-radius: .875rem;
}

.cube-introduction__details.cube-disclosure > summary:hover {
  background: transparent;
}

.cube-introduction__details.cube-disclosure > summary::before {
  grid-column: 2;
  grid-row: 2;
}

.cube-introduction__details .cube-introduction__copy {
  padding: 0 clamp(1.125rem, 1.75vw, 1.5rem) clamp(1.125rem, 1.75vw, 1.5rem);
}

.cube-introduction__number {
  grid-column: 1 / -1;
  grid-row: 1;
  display: flex;
  align-items: center;
  gap: .875rem;
  color: var(--accent);
  font-family: var(--project-font-mono);
  font-size: var(--project-text-label);
  font-weight: var(--project-weight-medium);
  line-height: var(--project-leading-tight);
  letter-spacing: var(--project-tracking-label);
}

.cube-introduction__number::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line-bright);
}

.cube-introduction__card h3 {
  min-width: 0;
  min-block-size: 2lh;
  display: flex;
  align-items: center;
  margin: 0;
  color: var(--fg);
  font-size: var(--project-text-card-title);
  font-weight: var(--project-weight-semibold);
  line-height: var(--project-leading-tight);
  letter-spacing: var(--project-tracking-lead);
  text-wrap: balance;
}

.cube-introduction__copy p,
.cube-introduction__note {
  margin: 0;
  color: var(--muted-bright);
  text-wrap: pretty;
  font-family: var(--project-font-body);
  font-size: var(--project-text-body);
  font-weight: var(--project-weight-regular);
  line-height: var(--project-leading-body);
  letter-spacing: var(--project-tracking-body);
}

.cube-introduction__card .cube-introduction__link {
  display: inline-block;
  min-height: 44px;
  margin-top: .75rem;
  padding-block: .5rem;
  color: color-mix(in srgb, var(--accent) 80%, var(--fg));
  font-size: var(--project-text-body);
  line-height: var(--project-leading-tight);
  text-decoration: underline;
  text-underline-offset: .2em;
  text-decoration-thickness: 1px;
}

.cube-introduction__link:hover { color: var(--fg); }

.cube-introduction__note {
  max-width: 80ch;
  margin-top: 1.5rem;
  padding-left: 1rem;
  border-left: 2px solid var(--accent);
  font-size: var(--project-text-small);
}

@media (min-width: 701px) {
  .cube-introduction__features { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1280px) {
  .cube-introduction__features { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

.cube-hardware,
.cube-physical-design {
  padding-block: clamp(5.5rem, 7.5vw, 7.5rem);
}

.cube-sections-ready [data-cube-reveal] {
  opacity: 0;
  transform: translate3d(0, .9rem, 0);
  transition: opacity 430ms ease, transform 520ms var(--cube-ease);
}

.cube-sections-ready [data-cube-reveal].is-visible {
  opacity: 1;
  transform: translate3d(0, 0, 0);
}

@media (max-width: 900px) {
  .cube-section {
    --cube-section-columns: 1fr;
    --cube-section-gap: 2.25rem;
  }

  .cube-section__rail {
    flex-direction: row-reverse;
    align-items: baseline;
    justify-content: space-between;
  }

  .cube-introduction__features {
    grid-template-columns: minmax(0, 1fr);
    gap: .75rem;
  }

  .cube-introduction__details.cube-disclosure > summary {
    gap: 0 1rem;
    padding: 1.125rem;
  }

  .cube-introduction__details.cube-disclosure > summary::before {
    grid-row: 1;
  }

  .cube-introduction__number { display: none; }

  .cube-introduction__details .cube-introduction__copy {
    padding: 0 1.125rem 1.125rem;
  }
}

@media (max-width: 700px) {
  .cube-section {
    padding-block: clamp(5rem, 13vw, 7rem);
  }
}

@media (max-width: 430px) {
  .cube-section {
    padding-block: 4.75rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  .cube-sections-ready [data-cube-reveal] {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
}