.page-about {
  background: var(--primary-bg);
  color: var(--text-silver);
}

.page-about .about-hero {
  position: relative;
  padding: 56px 0 68px;
  background: linear-gradient(180deg, rgba(255, 107, 53, 0.14) 0%, rgba(11, 27, 58, 0) 55%);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 6px;
  background: linear-gradient(90deg, var(--accent-orange) 0% 33%, var(--accent-green) 33% 66%, var(--line) 66% 100%);
}

.page-about .about-hero-grid {
  display: grid;
  gap: 40px;
  margin-top: 36px;
}

.page-about .about-hero h1 {
  margin: 16px 0 12px;
  font-family: var(--font-head);
  font-size: clamp(42px, 9vw, 84px);
  font-weight: 900;
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--text-white);
}

.page-about .about-hero-lead {
  margin: 0 0 18px;
  font-size: 21px;
  font-weight: 700;
  color: var(--accent-green);
}

.page-about .about-hero-desc {
  max-width: 640px;
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 28px;
}

.page-about .about-hero-aside {
  position: relative;
  padding: 26px 24px;
  background: var(--card-bg);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .about-aside-title {
  margin: 0 0 16px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .about-chapter-nav {
  display: grid;
  gap: 4px;
}

.page-about .about-chapter-nav a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 13px 10px;
  border-bottom: 1px solid rgba(46, 66, 100, 0.55);
  color: var(--text-silver);
  text-decoration: none;
  transition: background 0.25s ease-out, color 0.25s ease-out;
}

.page-about .about-chapter-nav a:last-child {
  border-bottom: 0;
}

.page-about .about-chapter-nav a:hover,
.page-about .about-chapter-nav a.is-spied {
  background: rgba(0, 255, 163, 0.1);
  color: var(--text-white);
}

.page-about .chapter-index {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--accent-orange);
}

.page-about .chapter-name {
  font-size: 15px;
  font-weight: 600;
}

.page-about .about-version-stamp {
  margin-top: 24px;
  padding: 18px 10px 4px;
  border-top: 2px dashed var(--line);
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.page-about .about-version-stamp span {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  color: var(--highlight-yellow);
  display: inline-block;
  transform: rotate(-3deg);
}

.page-about .about-version-stamp p {
  margin: 0;
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-section-heading {
  margin-top: 64px;
}

.page-about .section-heading-desc {
  max-width: 660px;
  margin: 12px 0 0;
  font-size: 16px;
  line-height: 1.8;
}

.page-about .about-section-heading h2 {
  margin: 14px 0 0;
  font-family: var(--font-head);
  font-size: clamp(30px, 6vw, 52px);
  font-weight: 900;
  line-height: 1.12;
  color: var(--text-white);
}

.page-about .about-milestones {
  position: relative;
  padding: 72px 0 88px;
  background:
    linear-gradient(rgba(18, 38, 77, 0.32) 1px, transparent 1px),
    linear-gradient(90deg, rgba(18, 38, 77, 0.32) 1px, transparent 1px);
  background-size: 44px 44px;
}

.page-about .timeline-intro {
  display: grid;
  gap: 20px;
  margin: 56px 0 64px;
  padding: 18px;
  background: var(--secondary-bg);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
}

.page-about .timeline-figure {
  margin: 0;
}

.page-about .timeline-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .timeline-figure figcaption {
  margin-top: 10px;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
}

.page-about .timeline-intro-copy {
  padding: 6px 4px 10px;
}

.page-about .timeline-intro-label {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.08em;
  color: var(--accent-green);
}

.page-about .timeline-intro-copy p:last-child {
  margin: 8px 0 0;
  line-height: 1.8;
}

.page-about .about-timeline {
  position: relative;
  margin: 24px 0 0;
}

.page-about .timeline-rail-svg {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 22px;
  width: 4px;
  transform: translateX(-50%);
  pointer-events: none;
  opacity: 0.9;
}

.page-about .timeline-node {
  position: relative;
  margin: 0 0 56px 68px;
}

.page-about .timeline-node::before {
  content: "";
  position: absolute;
  left: -55px;
  top: 22px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--accent-green);
  border: 4px solid var(--primary-bg);
  outline: 2px solid var(--accent-green);
  z-index: 2;
}

.page-about .timeline-node--right::before {
  background: var(--accent-orange);
  outline-color: var(--accent-orange);
}

.page-about .timeline-node-meta {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}

.page-about .timeline-year {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 800;
  color: var(--text-white);
}

.page-about .timeline-version {
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--accent-green);
  padding: 3px 10px;
  border: 1px solid rgba(0, 255, 163, 0.4);
  background: rgba(0, 255, 163, 0.1);
}

.page-about .timeline-node-card {
  padding: 22px;
  background: var(--card-bg);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  transition: transform 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}

.page-about .timeline-node-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent-green);
}

.page-about .timeline-node-card h3 {
  margin: 0 0 8px;
  font-size: 19px;
  font-weight: 700;
  color: var(--text-white);
}

.page-about .timeline-node-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
}

.page-about .about-stats {
  padding: 76px 0;
  background:
    radial-gradient(circle at 16% 0%, rgba(0, 255, 163, 0.14), transparent 42%),
    linear-gradient(180deg, var(--primary-bg) 0%, var(--secondary-bg) 100%);
  border-top: 3px solid var(--line);
  border-bottom: 3px solid var(--line);
}

.page-about .stats-board {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
  margin-top: 40px;
}

.page-about .stat-cell {
  position: relative;
  padding: 26px 20px;
  background: var(--card-bg);
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  transition: transform 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}

.page-about .stat-cell:hover {
  transform: translateY(-4px);
  border-color: var(--accent-green);
}

.page-about .stat-cell--accent:hover {
  border-color: var(--accent-orange);
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(40px, 7vw, 64px);
  font-weight: 800;
  line-height: 1;
  color: var(--text-white);
  margin-bottom: 10px;
}

.page-about .stat-unit {
  font-size: 0.52em;
  color: var(--accent-green);
  margin-left: 2px;
}

.page-about .stat-label {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--text-silver);
}

.page-about .stat-cell--hero {
  grid-column: span 2;
  background: var(--accent-green);
  border-color: var(--accent-green);
}

.page-about .stat-cell--hero .stat-num,
.page-about .stat-cell--hero .stat-label,
.page-about .stat-cell--hero .stat-unit {
  color: #06211f;
}

.page-about .stat-cell--hero p {
  margin: 14px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(6, 33, 31, 0.78);
}

.page-about .stat-cell--accent {
  border-color: rgba(255, 107, 53, 0.7);
}

.page-about .stat-cell--accent .stat-unit {
  color: var(--accent-orange);
}

.page-about .stat-cell--note {
  grid-column: span 2;
  background: transparent;
  border-style: dashed;
  display: flex;
  align-items: center;
  font-size: 15px;
  line-height: 1.8;
}

.page-about .about-principles {
  position: relative;
  padding: 76px 0 80px;
}

.page-about .principles-wrap {
  display: grid;
  gap: 36px;
  margin-top: 44px;
}

.page-about .principle-list {
  padding: 0;
  margin: 0;
  list-style: none;
  display: grid;
  gap: 22px;
}

.page-about .principle-item {
  display: flex;
  gap: 16px;
  padding: 22px 18px;
  background: var(--secondary-bg);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  border-left: 4px solid var(--accent-green);
  box-shadow: var(--shadow-hard);
}

.page-about .principle-item:nth-child(even) {
  border-left-color: var(--accent-orange);
}

.page-about .principle-num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 38px;
  font-weight: 800;
  line-height: 1;
  color: var(--accent-orange);
}

.page-about .principle-body h3 {
  margin: 0 0 6px;
  font-size: 19px;
  font-weight: 700;
  color: var(--text-white);
}

.page-about .principle-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
}

.page-about .principles-note {
  margin: 26px 0 0;
  padding: 16px 18px;
  border: 2px dashed var(--line);
  font-size: 14px;
  color: var(--muted);
}

.page-about .principles-figure {
  margin: 0;
  overflow: hidden;
  border: 2px solid var(--line);
  background: var(--secondary-bg);
  box-shadow: var(--shadow-hard);
}

.page-about .principles-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .principles-figure figcaption {
  margin: 12px 16px 16px;
  font-size: 14px;
  color: var(--muted);
  line-height: 1.6;
}

.page-about .about-ecosystem {
  padding: 84px 0 80px;
  background: var(--secondary-bg);
  border-top: 3px solid var(--line);
  clip-path: polygon(0 2.4%, 100% 0%, 100% 97.6%, 0% 100%);
}

.page-about .ecosystem-layout {
  display: grid;
  gap: 44px;
  margin-top: 64px;
}

.page-about .ecosystem-visual {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.page-about .concentric-chart {
  position: relative;
  width: min(320px, 100%);
  aspect-ratio: 1;
}

.page-about .concentric-ring {
  position: absolute;
  border: 3px solid var(--line);
  border-radius: 50%;
  background: var(--primary-bg);
  transition: border-color 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out);
}

.page-about .concentric-ring--outer {
  inset: 0;
  border-color: var(--accent-orange);
  background: radial-gradient(circle, transparent 50%, rgba(255, 107, 53, 0.12) 50%, rgba(255, 107, 53, 0.12) 100%);
}

.page-about .concentric-ring--mid {
  inset: 18%;
  border-color: var(--accent-green);
  background: radial-gradient(circle, transparent 42%, rgba(0, 255, 163, 0.14) 42%, rgba(0, 255, 163, 0.14) 100%);
}

.page-about .concentric-ring--core {
  inset: 36%;
  background: var(--accent-green);
  border-color: var(--accent-green);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 0 5px var(--primary-bg), 0 0 0 8px rgba(0, 255, 163, 0.6);
}

.page-about .concentric-ring:hover {
  box-shadow: 0 0 0 4px var(--primary-bg), 0 0 24px rgba(0, 255, 163, 0.35);
}

.page-about .ring-tag {
  position: absolute;
  z-index: 3;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--text-silver);
  background: rgba(11, 27, 58, 0.92);
  border: 1px solid var(--line);
  padding: 4px 8px;
  white-space: nowrap;
}

.page-about .ring-tag--top {
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
}

.page-about .ring-tag--bottom {
  bottom: -12px;
  left: 50%;
  transform: translateX(-50%);
}

.page-about .ring-tag--left {
  left: -16px;
  top: 50%;
  transform: translateY(-50%) translateX(-100%);
}

.page-about .ring-tag--right {
  right: -16px;
  top: 50%;
  transform: translateY(-50%) translateX(100%);
}

.page-about .ring-tag--center {
  position: static;
  background: transparent;
  border: 0;
  color: #06211f;
  font-size: 15px;
  font-weight: 800;
  font-family: var(--font-head);
  white-space: normal;
  text-align: center;
}

.page-about .ecosystem-visual-caption {
  font-size: 13px;
  color: var(--muted);
  text-align: center;
}

.page-about .ecosystem-content {
  display: grid;
  gap: 22px;
}

.page-about .ecosystem-lead {
  margin: 0;
  font-size: 17px;
  line-height: 1.8;
  font-weight: 500;
  color: var(--text-white);
}

.page-about .ecosystem-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 12px;
}

.page-about .ecosystem-list li {
  padding: 15px 18px;
  background: var(--card-bg);
  border-left: 3px solid var(--accent-green);
  font-size: 15px;
  line-height: 1.7;
}

.page-about .ecosystem-list li:nth-child(2) {
  border-left-color: var(--accent-orange);
}

.page-about .ecosystem-list li:nth-child(3) {
  border-left-color: var(--highlight-yellow);
}

.page-about .ecosystem-list strong {
  color: var(--text-white);
}

.page-about .ecosystem-figure {
  margin: 0;
}

.page-about .ecosystem-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ecosystem-figure figcaption {
  margin-top: 8px;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.6;
}

.page-about .about-next {
  padding: 72px 0 84px;
}

.page-about .next-links {
  display: grid;
  gap: 18px;
}

.page-about .next-links a {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 24px 20px;
  background: var(--secondary-bg);
  border: 2px solid var(--line);
  text-decoration: none;
  color: var(--text-silver);
  box-shadow: var(--shadow-hard);
  transition: transform 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}

.page-about .next-links a:hover {
  transform: translateX(6px);
  border-color: var(--accent-green);
}

.page-about .next-link-index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--accent-orange);
}

.page-about .next-link-title {
  margin-right: auto;
  font-size: 18px;
  font-weight: 700;
  color: var(--text-white);
}

.page-about .next-link-arrow {
  font-family: var(--font-mono);
  font-size: 20px;
  color: var(--accent-green);
}

@media (min-width: 768px) {
  .page-about .about-hero {
    padding: 68px 0 84px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: 1.2fr 0.8fr;
    gap: 56px;
    align-items: start;
    margin-top: 44px;
  }

  .page-about .timeline-intro {
    grid-template-columns: 300px 1fr;
    align-items: center;
  }

  .page-about .principles-wrap {
    grid-template-columns: 1fr 300px;
    align-items: start;
  }

  .page-about .ecosystem-layout {
    grid-template-columns: minmax(340px, 420px) 1fr;
    align-items: center;
    gap: 56px;
  }

  .page-about .next-links {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 992px) {
  .page-about .timeline-node {
    width: 50%;
    margin-left: 0;
    padding-right: 64px;
    text-align: right;
  }

  .page-about .timeline-node--right {
    margin-left: 50%;
    padding-right: 0;
    padding-left: 64px;
    text-align: left;
  }

  .page-about .timeline-node::before {
    left: auto;
    right: -9px;
    top: 26px;
  }

  .page-about .timeline-node--right::before {
    left: -9px;
    right: auto;
    background: var(--accent-orange);
    outline-color: var(--accent-orange);
  }

  .page-about .timeline-rail-svg {
    left: 50%;
  }

  .page-about .stats-board {
    grid-template-columns: repeat(6, 1fr);
  }

  .page-about .stat-cell--hero {
    grid-column: span 3;
    grid-row: span 2;
  }

  .page-about .stat-cell--note {
    grid-column: span 2;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about *,
  .page-about *::before,
  .page-about *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}