.page-about {
  --about-green-line: rgba(198, 255, 0, 0.45);
  --about-blue-line: rgba(0, 229, 255, 0.4);
  --about-orange-line: rgba(255, 138, 61, 0.35);
  position: relative;
  min-height: 60vh;
  background: linear-gradient(180deg, rgba(0, 229, 255, 0.03) 0%, transparent 300px);
}

.page-about .breadcrumbs {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1.25rem;
  padding: 0 1rem;
  font-size: 0.8rem;
  color: var(--text-weak);
}

.page-about .breadcrumb-sep {
  color: var(--accent-green);
  font-family: var(--font-data);
}

.page-about .breadcrumb-current {
  color: var(--text-main);
  font-weight: 500;
}

.page-about .about-hero {
  position: relative;
  padding: 2rem 1rem 1.5rem;
}

.page-about .about-hero-vertical {
  position: absolute;
  top: 3rem;
  right: 0.5rem;
  writing-mode: vertical-rl;
  font-size: 0.75rem;
  letter-spacing: 0.25em;
  color: var(--text-weak);
  opacity: 0.8;
  z-index: 2;
}

.page-about .about-hero-frame {
  position: relative;
  overflow: hidden;
  background: var(--bg-card);
  clip-path: polygon(0 0, calc(100% - 1.75rem) 0, 100% 1.75rem, 100% 100%, 1.75rem 100%, 0 calc(100% - 1.75rem));
  padding: 1.75rem 1.5rem 2.25rem;
}

.page-about .about-hero-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 78% 20%, rgba(0, 229, 255, 0.14) 0%, transparent 45%),
    radial-gradient(circle at 12% 85%, rgba(198, 255, 0, 0.1) 0%, transparent 40%);
  pointer-events: none;
}

.page-about .about-hero-frame::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 45%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent-green), var(--accent-blue));
}

.page-about .about-hero-index {
  display: inline-block;
  font-size: clamp(0.7rem, 2vw, 0.875rem);
  letter-spacing: 0.2em;
  color: var(--accent-green);
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  padding: 0.3rem 0.8rem;
  margin-bottom: 1.25rem;
  position: relative;
}

.page-about .about-hero-grid {
  position: relative;
  display: grid;
  gap: 1.75rem;
}

.page-about .about-hero-kicker {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  color: var(--accent-blue);
  margin-bottom: 0.75rem;
  padding: 0.25rem 0.75rem;
  border-left: 2px solid var(--accent-green);
  background: rgba(198, 255, 0, 0.06);
}

.page-about .about-hero-title h1 {
  font-size: clamp(1.6rem, 5vw, 2.7rem);
  font-weight: 900;
  line-height: 1.28;
  color: var(--text-main);
  margin: 0 0 1.25rem;
  letter-spacing: -0.02em;
  max-width: 920px;
}

.page-about .about-hero-desc {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--text-weak);
  max-width: 680px;
  margin-bottom: 1.75rem;
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.page-about .about-hero-count {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
  background: var(--bg-deep);
  border-radius: var(--radius-md);
  padding: 1.15rem 1.35rem;
  max-width: 520px;
  border: 1px solid var(--line);
}

.page-about .about-hero-count-item {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.page-about .about-hero-count-item span {
  font-size: 1.55rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1;
}

.page-about .about-hero-count-item small {
  font-size: 0.72rem;
  color: var(--text-weak);
  font-family: var(--font-body);
  letter-spacing: 0.05em;
}

.page-about .about-hero-count-current span {
  color: var(--accent-green);
}

.page-about .about-hero-count-arrow {
  color: var(--accent-blue);
  font-size: 1.2rem;
  font-weight: 600;
}

.page-about .about-hero-coord {
  margin-top: 1.5rem;
  padding-top: 0.85rem;
  border-top: 1px dashed var(--line);
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  color: var(--text-weak);
  display: flex;
  justify-content: flex-end;
  text-transform: uppercase;
}

.page-about .about-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  padding: 2rem 1rem 4rem;
}

.page-about .about-side-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: flex-start;
  border-bottom: 1px dashed var(--line);
  padding-bottom: 1rem;
}

.page-about .about-side-nav-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 0.9rem;
  border-radius: var(--radius-pill);
  background: var(--bg-card);
  color: var(--text-weak);
  font-size: 0.78rem;
  letter-spacing: 0.06em;
  text-decoration: none;
  border: 1px solid transparent;
  transition: all var(--speed) var(--ease);
  position: relative;
}

.page-about .about-side-nav-link i {
  color: var(--accent-green);
  font-style: normal;
  font-weight: 600;
}

.page-about .about-side-nav-link:hover,
.page-about .about-side-nav-link:focus-visible {
  color: var(--text-main);
  border-color: var(--accent-green);
  background: var(--bg-float);
  transform: translateY(-2px);
}

.page-about .about-main {
  display: flex;
  flex-direction: column;
  gap: 5rem;
}

.page-about .about-section {
  position: relative;
  scroll-margin-top: 6rem;
}

.page-about .chapter-header {
  position: relative;
  margin-bottom: 2.25rem;
  transition: all var(--speed) var(--ease);
}

.page-about .chapter-header::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 3px;
  height: 100%;
  background: linear-gradient(180deg, var(--accent-green) 0%, var(--accent-blue) 100%);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform var(--speed) var(--ease);
}

.page-about .chapter-header:hover::before {
  transform: scaleY(1);
}

.page-about .chapter-header .chapter-index {
  color: var(--accent-green);
  font-size: 1.05rem;
  font-weight: 600;
}

.page-about .chapter-header .chapter-title {
  font-size: clamp(1.3rem, 3vw, 2rem);
  font-weight: 900;
  color: var(--text-main);
  margin: 0.25rem 0 0;
}

.page-about .chapter-header .chapter-meta {
  color: var(--text-weak);
  font-size: 0.88rem;
  margin-top: 0.3rem;
}

.page-about .about-archive-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.page-about .about-archive-image {
  position: relative;
}

.page-about .about-img-main {
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  display: block;
}

.page-about .about-archive-coord {
  position: absolute;
  bottom: 1rem;
  left: 1rem;
  background: rgba(11, 15, 20, 0.88);
  border: 1px solid rgba(198, 255, 0, 0.35);
  border-radius: var(--radius-pill);
  padding: 0.35rem 0.85rem;
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--accent-green);
  backdrop-filter: blur(4px);
}

.page-about .about-archive-card {
  position: relative;
  padding: 1.65rem 1.5rem 1.5rem;
  min-height: 240px;
}

.page-about .about-archive-card::after {
  content: "";
  position: absolute;
  top: 1rem;
  right: 1rem;
  width: 3.2rem;
  height: 3.2rem;
  background: linear-gradient(135deg, transparent 45%, rgba(0, 229, 255, 0.15) 45%, rgba(0, 229, 255, 0.15) 55%, transparent 55%);
  background-size: 0.75rem 0.75rem;
  border-radius: var(--radius-sm);
  pointer-events: none;
}

.page-about .about-card-index {
  display: inline-block;
  color: var(--accent-blue);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  margin-bottom: 1rem;
  padding: 0.2rem 0.7rem;
  border-radius: var(--radius-xs);
  background: rgba(0, 229, 255, 0.08);
}

.page-about .about-archive-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 0 0 0.85rem;
}

.page-about .about-archive-card p {
  color: var(--text-weak);
  font-size: 0.93rem;
  line-height: 1.75;
  margin-bottom: 1.1rem;
}

.page-about .about-archive-list {
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.7rem;
}

.page-about .about-archive-list li {
  display: flex;
  align-items: flex-start;
  gap: 0.55rem;
  color: var(--text-main);
  font-size: 0.9rem;
  line-height: 1.65;
}

.page-about .about-archive-list .legend-dot {
  flex: 0 0 auto;
  margin-top: 0.4rem;
}

.page-about .about-archive-note {
  font-size: 0.82rem;
  color: var(--text-weak);
  border-left: 2px solid var(--accent-orange);
  padding-left: 0.75rem;
  background: rgba(255, 138, 61, 0.06);
  border-radius: 0 var(--radius-xs) var(--radius-xs) 0;
  line-height: 1.5;
}

.page-about .about-timeline-wrap {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

.page-about .about-timeline {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 1.8rem;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 1.05rem;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--accent-green) 0%, var(--accent-blue) 50%, rgba(198, 255, 0, 0.4) 100%);
}

.page-about .about-timeline-item {
  position: relative;
  padding-left: 3.2rem;
  background: transparent;
  border: none;
  border-radius: 0;
}

.page-about .about-timeline-item[open] .about-timeline-body {
  animation: about-reveal-item 0.4s var(--ease);
}

@keyframes about-reveal-item {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.page-about .about-timeline-summary {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.55rem;
  cursor: pointer;
  padding: 0.6rem 0;
  user-select: none;
}

.page-about .about-timeline-summary::-webkit-details-marker {
  display: none;
}

.page-about .about-timeline-summary:hover .about-timeline-title {
  color: var(--accent-green);
}

.page-about .about-timeline-summary:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: 4px;
  border-radius: var(--radius-sm);
}

.page-about .about-timeline-dot {
  position: absolute;
  left: 0.55rem;
  top: 0.85rem;
  width: 0.9rem;
  height: 0.9rem;
  border-radius: 50%;
  background: var(--accent-green);
  border: 3px solid var(--bg-deep);
  box-shadow: 0 0 0 2px rgba(198, 255, 0, 0.45);
  z-index: 1;
}

.page-about .about-timeline-dot-current {
  background: var(--accent-blue);
  box-shadow: 0 0 0 2px rgba(0, 229, 255, 0.5), 0 0 14px rgba(0, 229, 255, 0.45);
}

.page-about .about-timeline-version {
  color: var(--accent-blue);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  background: rgba(0, 229, 255, 0.08);
  border-radius: var(--radius-pill);
  padding: 0.2rem 0.65rem;
}

.page-about .about-timeline-year {
  color: var(--accent-green);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.1em;
}

.page-about .about-timeline-title {
  color: var(--text-main);
  font-size: 1.06rem;
  font-weight: 700;
  transition: color var(--speed) var(--ease);
}

.page-about .about-timeline-body {
  margin-top: 0.85rem;
  padding: 1.1rem 1.2rem;
  position: relative;
  transition: background var(--speed) var(--ease);
}

.page-about .about-timeline-item:hover .about-timeline-body {
  background: var(--bg-float);
}

.page-about .about-timeline-body p {
  color: var(--text-weak);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 0.8rem;
}

.page-about .about-timeline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.page-about .about-timeline-tags span {
  font-size: 0.75rem;
  padding: 0.2rem 0.75rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line);
  color: var(--accent-silver);
  background: rgba(11, 15, 20, 0.6);
  letter-spacing: 0.03em;
}

.page-about .about-timeline-art {
  display: none;
}

.page-about .about-data-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.page-about .about-data-main {
  padding: 1.75rem 1.5rem;
}

.page-about .about-data-main h3 {
  font-size: 1.2rem;
  color: var(--text-main);
  font-weight: 700;
  margin: 0 0 0.85rem;
}

.page-about .about-data-main p {
  color: var(--text-weak);
  font-size: 0.93rem;
  line-height: 1.75;
  margin-bottom: 1.4rem;
}

.page-about .about-data-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  border-top: 1px dashed var(--line);
  padding-top: 1.2rem;
}

.page-about .about-data-legend .legend-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--text-main);
  font-size: 0.88rem;
}

.page-about .about-data-cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
}

.page-about .about-data-stat {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  padding: 1.15rem 1.1rem;
  min-height: 92px;
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  margin: 0;
  border-radius: var(--radius-md);
  background: var(--bg-card);
}

.page-about .about-data-stat::after {
  content: "";
  position: absolute;
  right: -10px;
  bottom: -10px;
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, transparent 45%, rgba(0, 229, 255, 0.12) 45%, rgba(0, 229, 255, 0.12) 55%, transparent 55%);
  background-size: 10px 10px;
  border-radius: var(--radius-xs);
}

.page-about .about-stat-num {
  font-size: 2.2rem;
  font-weight: 600;
  color: var(--accent-green);
  line-height: 1.1;
  margin-bottom: 0.3rem;
}

.page-about .about-data-stat:nth-child(2) .about-stat-num {
  color: var(--accent-blue);
}

.page-about .about-data-stat:nth-child(3) .about-stat-num {
  color: var(--accent-orange);
}

.page-about .about-data-stat:nth-child(4) .about-stat-num {
  color: var(--accent-silver);
}

.page-about .about-stat-label {
  font-size: 0.82rem;
  color: var(--text-weak);
  letter-spacing: 0.05em;
}

.page-about .about-data-note {
  display: flex;
  align-items: flex-start;
  gap: 0.85rem;
  padding: 0.9rem 1.2rem;
  background: rgba(255, 138, 61, 0.05);
  border: 1px dashed rgba(255, 138, 61, 0.3);
  margin-top: 1.1rem;
}

.page-about .about-data-note .font-data {
  color: var(--accent-orange);
  font-weight: 600;
  white-space: nowrap;
}

.page-about .about-data-note p {
  color: var(--text-weak);
  font-size: 0.85rem;
  line-height: 1.65;
  margin: 0;
}

.page-about .about-commit-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.page-about .about-commit-main {
  padding: 1.75rem 1.5rem;
  position: relative;
  overflow: hidden;
}

.page-about .about-commit-main::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 60px;
  height: 60px;
  background: linear-gradient(225deg, rgba(198, 255, 0, 0.18), transparent 60%);
  border-radius: 0 var(--radius-md) 0 0;
}

.page-about .about-commit-main h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 0 0 0.85rem;
}

.page-about .about-commit-main > p {
  color: var(--text-weak);
  font-size: 0.93rem;
  line-height: 1.75;
  margin-bottom: 1.4rem;
}

.page-about .about-commit-list {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.page-about .about-commit-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.65rem 0.9rem;
  background: var(--bg-deep);
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: all var(--speed) var(--ease);
}

.page-about .about-commit-item:hover {
  border-color: rgba(198, 255, 0, 0.3);
  transform: translateX(4px);
}

.page-about .about-commit-item .font-data {
  color: var(--accent-green);
  font-weight: 600;
  font-size: 0.9rem;
  width: 1.8rem;
  flex: 0 0 1.8rem;
  text-align: center;
  background: rgba(198, 255, 0, 0.08);
  border-radius: var(--radius-xs);
  padding: 0.15rem 0;
}

.page-about .about-commit-item:not(:has(.font-data)) .font-data {
  display: inline-block;
}

.page-about .about-commit-item {
  color: var(--text-main);
  font-size: 0.9rem;
  line-height: 1.55;
}

.page-about .about-commit-side {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.page-about .about-commit-side img {
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
}

.page-about .about-commit-note {
  padding: 1.2rem 1.3rem;
  background: var(--bg-float);
  border: 1px solid rgba(0, 229, 255, 0.25);
}

.page-about .about-commit-note .font-data {
  display: block;
  color: var(--accent-blue);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  margin-bottom: 0.5rem;
}

.page-about .about-commit-note p {
  color: var(--text-weak);
  font-size: 0.88rem;
  line-height: 1.7;
  margin: 0;
}

@media (min-width: 768px) {
  .page-about .about-hero-frame {
    padding: 2.5rem 2.5rem 2.5rem;
  }

  .page-about .about-hero-grid {
    grid-template-columns: 1fr auto;
    align-items: start;
    gap: 2rem;
  }

  .page-about .about-hero-count {
    flex-direction: column;
    align-items: flex-start;
    margin-top: 0.4rem;
    min-width: 200px;
  }

  .page-about .about-hero-count-arrow {
    transform: rotate(90deg);
  }

  .page-about .about-archive-grid {
    grid-template-columns: 1.1fr 1fr;
    align-items: stretch;
  }

  .page-about .about-archive-image {
    order: 1;
  }

  .page-about .about-archive-card {
    order: 2;
  }

  .page-about .about-timeline-wrap {
    grid-template-columns: 1fr;
  }

  .page-about .about-data-grid {
    grid-template-columns: 1.2fr 0.8fr;
  }

  .page-about .about-commit-grid {
    grid-template-columns: 1.2fr 0.8fr;
  }

  .page-about .about-commit-side {
    order: -1;
  }
}

@media (min-width: 1024px) {
  .page-about .about-hero {
    padding: 2.5rem 1rem 2rem;
  }

  .page-about .about-hero-vertical {
    right: 0.2rem;
    top: 3.5rem;
    font-size: 0.82rem;
  }

  .page-about .about-layout {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 2.75rem;
    padding: 2.5rem 1rem 5rem;
  }

  .page-about .about-side-nav {
    position: sticky;
    top: 6.5rem;
    align-self: start;
    flex-direction: column;
    gap: 0.45rem;
    border-bottom: none;
    padding-bottom: 0;
  }

  .page-about .about-side-nav-link {
    width: 100%;
    justify-content: space-between;
    border-radius: var(--radius-sm);
    padding: 0.65rem 0.9rem;
    background: transparent;
  }

  .page-about .about-side-nav-link:hover {
    background: var(--bg-float);
  }

  .page-about .about-timeline-wrap {
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 2.25rem;
    align-items: start;
  }

  .page-about .about-timeline-art {
    display: block;
    position: sticky;
    top: 7rem;
  }

  .page-about .about-timeline-art img {
    width: 100%;
    height: auto;
    object-fit: cover;
    border-radius: var(--radius-md);
    border: 1px solid var(--line);
    transform: rotate(1.5deg);
    transition: transform var(--speed) var(--ease);
  }

  .page-about .about-timeline-art:hover img {
    transform: rotate(0) scale(1.02);
  }

  .page-about .about-commit-item {
    padding: 0.75rem 1rem;
  }
}

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