.page-about {
  --about-line-color: rgba(192, 192, 192, 0.35);
  --about-section-space-mobile: 72px;
  --about-section-space-desktop: 120px;
  --about-accent-soft: rgba(255, 107, 0, 0.08);
}

.page-about__hero {
  position: relative;
  background: var(--color-primary);
  color: var(--color-white);
  overflow: hidden;
  padding: 40px 0 64px;
  min-height: 480px;
  display: flex;
  align-items: center;
}
.page-about__hero-bg-wrap {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.page-about__hero-bg {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  opacity: 0.22;
}
.page-about__hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(118deg, rgba(10, 31, 68, 0.96) 12%, rgba(10, 31, 68, 0.62) 52%, rgba(255, 107, 0, 0.22) 100%);
}
.page-about__hero .container {
  position: relative;
  z-index: 2;
}
.page-about__hero .breadcrumb {
  margin-bottom: 32px;
}
.page-about__hero .breadcrumb__link,
.page-about__hero .breadcrumb__current {
  color: rgba(255, 255, 255, 0.78);
  font-size: 13px;
}
.page-about__hero .breadcrumb__link:hover {
  color: var(--color-accent);
}
.page-about__hero-index {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--color-accent);
  border: 1px solid rgba(255, 107, 0, 0.6);
  padding: 6px 10px;
  margin-bottom: 20px;
  background: rgba(10, 31, 68, 0.4);
}
.page-about__hero-title {
  margin: 0 0 20px;
  font-size: 52px;
  line-height: 1.04;
  font-weight: 900;
  letter-spacing: -0.02em;
}
.page-about__hero-subtitle {
  margin: 0;
  max-width: 34em;
  font-size: 16px;
  line-height: 1.75;
  color: rgba(255, 255, 255, 0.85);
}

.page-about__origin,
.page-about__tech,
.page-about__index {
  padding: var(--about-section-space-mobile) 0;
  background: var(--color-white);
}
.page-about__milestones,
.page-about__ecosystem {
  padding: var(--about-section-space-mobile) 0;
  background: var(--color-primary);
  color: var(--color-white);
}
.page-about__credential {
  padding: var(--about-section-space-mobile) 0;
  background: var(--color-light-gray);
}

.page-about__section-head {
  margin-bottom: 40px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.page-about__section-head .label-tag {
  align-self: flex-start;
}
.page-about__section-title-block {
  max-width: 720px;
}
.page-about__section-title {
  margin: 0;
  font-size: 32px;
  line-height: 1.15;
  font-weight: 900;
  letter-spacing: -0.02em;
  color: var(--color-text);
}
.page-about__section-lead {
  margin: 10px 0 0;
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text-secondary);
}
.page-about__section-head--dark .page-about__section-title {
  color: var(--color-white);
}
.page-about__section-head--dark .page-about__section-lead {
  color: rgba(255, 255, 255, 0.7);
}

.page-about__origin-grid {
  display: grid;
  gap: 40px;
  grid-template-columns: 1fr;
}
.page-about__origin-copy p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--color-text);
}
.page-about__origin-aside {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.page-about__origin-stat {
  padding: 24px 20px;
  background: var(--color-light-gray);
  border: 2px solid var(--color-primary);
  box-shadow: var(--shadow-brutal);
}
.page-about__origin-stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 40px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--color-accent);
}
.page-about__origin-stat-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  color: var(--color-text-secondary);
}

.page-about__timeline-wrap {
  display: grid;
  gap: 36px;
  grid-template-columns: 1fr;
}
.page-about__milestone {
  position: relative;
  margin-bottom: 20px;
  padding-left: 40px;
}
.page-about__milestone::before {
  content: '';
  position: absolute;
  left: 0;
  top: 22px;
  width: 18px;
  height: 18px;
  border: 3px solid var(--color-accent);
  background: var(--color-primary);
  transform: rotate(45deg);
}
.page-about__milestone::after {
  content: '';
  position: absolute;
  left: 6px;
  top: 36px;
  bottom: -22px;
  width: 2px;
  background: rgba(255, 255, 255, 0.22);
}
.page-about__milestone:last-child::after {
  display: none;
}
.page-about__milestone-trigger {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  min-height: 56px;
  margin: 0;
  padding: 12px 16px;
  background: transparent;
  border: 2px solid rgba(255, 255, 255, 0.28);
  color: var(--color-white);
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 700;
  text-align: left;
  cursor: pointer;
}
.page-about__milestone-trigger:hover {
  border-color: var(--color-accent);
}
.page-about__milestone-year {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--color-accent);
  white-space: nowrap;
  letter-spacing: 0.04em;
}
.page-about__milestone-name {
  flex: 1;
}
.page-about__milestone-icon {
  font-family: var(--font-mono);
  font-size: 22px;
  line-height: 1;
  color: var(--color-accent);
  transform: rotate(0deg);
  transition: transform 0.25s ease;
}
.page-about__milestone[data-open] .page-about__milestone-icon {
  transform: rotate(45deg);
}
.page-about__milestone-body {
  padding: 14px 16px;
  border: 2px solid rgba(255, 255, 255, 0.28);
  border-top: 0;
}
.page-about__milestone-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.85);
}
.page-about__milestone[data-open] .page-about__milestone-body {
  background: var(--about-accent-soft);
  border-color: rgba(255, 107, 0, 0.5);
}

.page-about__timeline-visual {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.page-about__timeline-img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
  border: 2px solid rgba(255, 255, 255, 0.26);
  box-shadow: 8px 8px 0 rgba(255, 107, 0, 0.2);
}
.page-about__timeline-note {
  padding: 14px 16px;
  border-left: 3px solid var(--color-accent);
  background: rgba(255, 255, 255, 0.08);
}
.page-about__timeline-note-index {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  margin-bottom: 6px;
}
.page-about__timeline-note-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.65;
  color: rgba(255, 255, 255, 0.82);
}

.page-about__tech-grid {
  display: grid;
  gap: 32px;
  grid-template-columns: 1fr;
}
.page-about__tech-metrics {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
.page-about__metric {
  padding: 22px 18px;
  border: 2px solid var(--color-primary);
  box-shadow: var(--shadow-brutal);
  background: var(--color-white);
}
.page-about__metric--lg {
  grid-column: 1 / -1;
  background: var(--color-primary);
  color: var(--color-white);
}
.page-about__metric-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 700;
  line-height: 1.15;
  color: var(--color-accent);
}
.page-about__metric--lg .page-about__metric-num {
  color: var(--color-white);
}
.page-about__metric-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--color-text-secondary);
}
.page-about__metric--lg .page-about__metric-label {
  color: rgba(255, 255, 255, 0.72);
}
.page-about__tech-copy p {
  margin: 0 0 16px;
  font-size: 16px;
  line-height: 1.85;
  color: var(--color-text);
}
.page-about__tech-pipeline {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-top: 24px;
}
.page-about__pipeline-item {
  padding: 14px;
  border: 1px solid var(--color-silver);
  background: var(--color-light-gray);
}
.page-about__pipeline-index {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-accent);
  margin-bottom: 6px;
}
.page-about__tech-img {
  width: 100%;
  height: auto;
  display: block;
  margin-top: 32px;
  border: 2px solid var(--color-primary);
  box-shadow: var(--shadow-brutal);
}
.page-about__tech-note {
  margin-top: 16px;
  padding: 12px 16px;
  border-left: 3px solid var(--color-accent);
  background: var(--color-light-gray);
  font-size: 14px;
  line-height: 1.65;
  color: var(--color-text-secondary);
}

.page-about__credential-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: 1fr;
}
.page-about__credential-card {
  position: relative;
  padding: 28px 24px;
  background: var(--color-white);
  border: 2px solid var(--color-primary);
  box-shadow: var(--shadow-brutal);
}
.page-about__credential-card::after {
  content: '';
  position: absolute;
  right: -2px;
  bottom: -2px;
  width: 18px;
  height: 18px;
  background: var(--color-accent);
}
.page-about__credential-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-accent);
  margin-bottom: 12px;
}
.page-about__credential-card h3 {
  margin: 0 0 8px;
  font-size: 20px;
  font-weight: 900;
  color: var(--color-text);
}
.page-about__credential-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

.page-about__ecosystem-grid {
  display: grid;
  gap: 20px;
  grid-template-columns: 1fr;
}
.page-about__ecosystem-card {
  padding: 28px 24px;
  border: 2px solid rgba(255, 255, 255, 0.26);
}
.page-about__ecosystem-icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  background: var(--color-accent);
  color: var(--color-primary);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  transform: rotate(45deg);
}
.page-about__ecosystem-icon span {
  display: block;
  transform: rotate(-45deg);
}
.page-about__ecosystem-card h3 {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--color-white);
}
.page-about__ecosystem-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.75);
}
.page-about__ecosystem-note {
  margin-top: 36px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  font-size: 14px;
  line-height: 1.65;
  color: rgba(255, 255, 255, 0.6);
}

.page-about__index-head {
  margin-bottom: 24px;
}

@media (min-width: 768px) {
  .page-about__hero {
    min-height: 560px;
    padding: 64px 0 88px;
  }
  .page-about__hero-title {
    font-size: 72px;
  }
  .page-about__hero-subtitle {
    font-size: 18px;
  }
  .page-about__section-title {
    font-size: 40px;
  }
  .page-about__section-head {
    margin-bottom: 48px;
  }
  .page-about__credential-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .page-about__ecosystem-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .page-about__tech-pipeline {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (min-width: 1024px) {
  .page-about__hero {
    padding: 72px 0 104px;
    min-height: 600px;
  }
  .page-about__hero-title {
    font-size: 84px;
  }
  .page-about__origin,
  .page-about__tech,
  .page-about__credential,
  .page-about__ecosystem,
  .page-about__index,
  .page-about__milestones {
    padding: var(--about-section-space-desktop) 0;
  }
  .page-about__origin-grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 64px;
  }
  .page-about__origin-aside {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .page-about__timeline-wrap {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 64px;
    align-items: start;
  }
  .page-about__tech-grid {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
    gap: 56px;
    align-items: start;
  }
  .page-about__ecosystem-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}