.page-about {
  --about-ink: #111111;
  --about-paper: #ffffff;
  --about-night: #1A1A2E;
  --about-yellow: #FFD166;
  --about-orange: #F4A261;
  --about-lake: #4ECDC4;
  --about-green: #2EC4B6;
  --about-neon: #06FFA5;
  --about-hot: #FF6B35;
}

.page-about .content-wrap {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 1.25rem;
  box-sizing: border-box;
}

.page-about .about-hero {
  background: var(--about-night);
  color: var(--about-paper);
  padding: 2rem 1.25rem 2.5rem;
}

.page-about .about-hero__inner {
  max-width: 1180px;
  margin: 0 auto;
}

.page-about .about-hero .breadcrumb {
  margin-bottom: 2rem;
}

.page-about .about-hero .breadcrumb a {
  color: var(--about-neon);
  text-decoration: none;
  font-weight: 500;
}

.page-about .about-hero .breadcrumb a:hover,
.page-about .about-hero .breadcrumb a:focus-visible {
  text-decoration: underline;
}

.page-about .about-hero__layout {
  display: grid;
  gap: 2rem;
  align-items: start;
}

.page-about .about-hero__eyebrow {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--about-neon);
  margin: 0 0 0.6rem;
}

.page-about .about-hero h1,
.page-about .about-hero__lead,
.page-about .about-hero__kw,
.page-about .about-hero__stats {
  margin-top: 0;
}

.page-about .about-hero__intro h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.7rem, 5vw, 2.6rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
  color: var(--about-paper);
}

.page-about .about-hero__lead {
  font-size: 0.95rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 1.4rem;
}

.page-about .about-hero__kw {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
  padding: 0;
}

.page-about .about-hero__kw-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: var(--radius-pill);
  padding: 0.3rem 0.8rem;
  color: var(--about-paper);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.4;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.page-about a.about-hero__kw-item:hover,
.page-about a.about-hero__kw-item:focus-visible {
  background: rgba(6, 255, 165, 0.14);
  border-color: var(--about-neon);
  outline: none;
}

.page-about .about-hero__kw-type {
  flex: 0 0 auto;
  background: var(--about-neon);
  color: var(--about-ink);
  border-radius: var(--radius-pill);
  padding: 0.1rem 0.45rem;
  font-weight: 700;
  font-size: 0.68rem;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.page-about .about-hero__stat {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: var(--radius-lg);
  padding: 1.1rem 0.8rem;
  text-align: center;
  backdrop-filter: blur(4px);
}

.page-about .about-hero__stat--main {
  grid-column: span 2;
  background: var(--about-neon);
  border-color: var(--about-neon);
  color: var(--about-ink);
  padding: 1.4rem 0.8rem;
}

.page-about .about-hero__stat-num {
  display: block;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.9rem;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.page-about .about-hero__stat-label {
  display: block;
  font-size: 0.78rem;
  opacity: 0.85;
  margin-top: 0.25rem;
  letter-spacing: 0.04em;
}

.page-about .about-section {
  padding: 3rem 0;
}

.page-about .about-section--yellow {
  background: var(--about-yellow);
  color: var(--about-ink);
}

.page-about .about-section--orange {
  background: var(--about-orange);
  color: var(--about-ink);
}

.page-about .about-section--lake {
  background: var(--about-lake);
  color: var(--about-ink);
}

.page-about .about-section--green {
  background: var(--about-green);
  color: var(--about-ink);
}

.page-about .about-section--night {
  background: var(--about-night);
  color: var(--about-paper);
}

.page-about .about-section--search {
  background: var(--about-paper);
  color: var(--about-ink);
}

.page-about .about-section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem;
  margin-bottom: 0.6rem;
}

.page-about .about-section__head .section-title {
  margin-bottom: 0;
}

.page-about .about-section__lead {
  font-size: 0.92rem;
  line-height: 1.75;
  max-width: 72ch;
  margin: 0 0 1.8rem;
}

.page-about .about-section--night .about-section__lead {
  color: rgba(255, 255, 255, 0.82);
}

.page-about .about-scale {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.9rem;
  align-items: stretch;
}

.page-about .about-scale__total {
  background: var(--about-paper);
  border: 3px solid var(--about-ink);
  border-radius: var(--radius-lg);
  box-shadow: 6px 6px 0 rgba(17, 17, 17, 0.9);
  padding: 1.6rem 1.2rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 150px;
}

.page-about .about-scale__total-num {
  font-family: var(--font-heading);
  font-size: 3rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--about-ink);
}

.page-about .about-scale__total-label {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  margin-top: 0.35rem;
}

.page-about .about-scale__total-meta {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  margin-top: 0.6rem;
  opacity: 0.72;
}

.page-about .about-scale__card {
  background: var(--about-paper);
  border: 2px solid var(--about-ink);
  border-radius: var(--radius-md);
  padding: 1rem 1rem 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.page-about .about-scale__card:hover {
  transform: translateY(-3px);
  box-shadow: 4px 4px 0 rgba(17, 17, 17, 0.35);
}

.page-about .about-scale__row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}

.page-about .about-scale__name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.02rem;
}

.page-about .about-scale__num {
  font-family: var(--font-heading);
  font-size: 1.7rem;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.page-about .about-scale .metric-bar {
  margin-top: 0.2rem;
}

.page-about .about-figure {
  margin: 2.2rem 0 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.45);
  padding: 0.75rem;
  border: 2px solid rgba(17, 17, 17, 0.14);
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: calc(var(--radius-lg) - 6px);
  object-fit: cover;
}

.page-about .about-taxo {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1.8rem;
  align-items: start;
}

.page-about .about-tree {
  display: flex;
  flex-direction: column;
  gap: 0;
  background: rgba(255, 255, 255, 0.32);
  border: 2px solid var(--about-ink);
  border-radius: var(--radius-lg);
  padding: 0.9rem;
}

.page-about .about-tree__root {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: var(--about-ink);
  color: var(--about-paper);
  border-radius: var(--radius-md);
  padding: 0.7rem 0.9rem;
  margin-bottom: 0.7rem;
}

.page-about .about-tree__root-name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.05rem;
}

.page-about .about-tree__badge {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background: var(--about-neon);
  color: var(--about-ink);
  border-radius: var(--radius-pill);
  padding: 0.15rem 0.6rem;
  font-weight: 700;
}

.page-about .about-tree__item {
  border-left: 3px solid rgba(17, 17, 17, 0.28);
  margin-left: 0.6rem;
  padding-left: 0.7rem;
  margin-bottom: 0.55rem;
}

.page-about .about-tree__bar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--about-paper);
  border: 2px solid var(--about-ink);
  border-radius: var(--radius-md);
  padding: 0.5rem 0.7rem;
}

.page-about .about-tree__name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.95rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.page-about .about-tree__count {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  background: rgba(17, 17, 17, 0.08);
  border-radius: var(--radius-pill);
  padding: 0.15rem 0.5rem;
  white-space: nowrap;
}

.page-about .about-tree__toggle {
  margin-left: auto;
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  background: var(--about-ink);
  color: var(--about-paper);
  border: 0;
  border-radius: var(--radius-pill);
  padding: 0.25rem 0.6rem;
  cursor: pointer;
  transition: background 0.18s ease, color 0.18s ease;
}

.page-about .about-tree__toggle:hover,
.page-about .about-tree__toggle:focus-visible {
  background: var(--about-hot);
  color: var(--about-ink);
  outline: none;
}

.page-about .about-tree__sub {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding: 0.55rem 0.6rem 0.65rem 0.8rem;
}

.page-about .about-tree__sub[data-open="false"] {
  display: none;
}

.page-about .about-tree .tag-item {
  margin: 0;
  padding: 0.22rem 0.55rem;
  border-radius: var(--radius-pill);
  font-size: 0.75rem;
}

.page-about .about-figure--taxo img {
  max-height: 360px;
}

.page-about .about-update__flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.8rem;
  margin-bottom: 1.6rem;
  counter-reset: update-step;
}

.page-about .about-update__step {
  display: flex;
  align-items: flex-start;
  gap: 0.9rem;
  background: rgba(255, 255, 255, 0.32);
  border: 2px solid rgba(17, 17, 17, 0.7);
  border-radius: var(--radius-md);
  padding: 0.9rem 1rem;
  position: relative;
}

.page-about .about-update__step-num {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  width: 2rem;
  height: 2rem;
  background: var(--about-neon);
  color: var(--about-ink);
  border-radius: 50%;
  border: 2px solid var(--about-ink);
}

.page-about .about-update__step-body {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.page-about .about-update__step-name {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.01rem;
}

.page-about .about-update__step-desc {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  opacity: 0.78;
  line-height: 1.45;
}

.page-about .about-version {
  display: flex;
  flex-direction: column;
  gap: 0;
  position: relative;
  padding-left: 1.5rem;
  border-left: 4px solid rgba(255, 255, 255, 0.35);
}

.page-about .about-version__item {
  position: relative;
  padding: 1rem 0 1rem 1.1rem;
  transition: background 0.18s ease;
}

.page-about .about-version__item::before {
  content: "";
  position: absolute;
  left: -2.05rem;
  top: 1.4rem;
  width: 0.9rem;
  height: 0.9rem;
  border-radius: 50%;
  background: var(--about-green);
  border: 3px solid var(--about-ink);
  box-sizing: border-box;
}

.page-about .about-version__item--current::before {
  background: var(--about-neon);
  box-shadow: 0 0 0 5px rgba(6, 255, 165, 0.3);
}

.page-about .about-version__mark {
  display: inline-block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.05rem;
  background: var(--about-paper);
  color: var(--about-ink);
  border: 2px solid var(--about-ink);
  border-radius: var(--radius-pill);
  padding: 0.15rem 0.8rem;
  margin-bottom: 0.45rem;
}

.page-about .about-version__item--current .about-version__mark {
  background: var(--about-neon);
}

.page-about .about-version__detail {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.page-about .about-version__tag {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  background: rgba(255, 255, 255, 0.82);
  color: var(--about-ink);
  border-radius: var(--radius-pill);
  padding: 0.15rem 0.55rem;
  font-weight: 700;
}

.page-about .about-version__detail p {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.65;
  color: rgba(17, 17, 17, 0.86);
  max-width: 60ch;
}

.page-about .about-device {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
}

.page-about .about-device__card {
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius-lg);
  padding: 1.4rem 1.2rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  transition: transform 0.18s ease, border-color 0.18s ease;
}

.page-about .about-device__card:hover {
  transform: translateY(-2px);
  border-color: var(--about-neon);
}

.page-about .about-device__card--cross {
  background: rgba(6, 255, 165, 0.1);
}

.page-about .about-device__icon {
  width: 2.4rem;
  height: 2.4rem;
  color: var(--about-neon);
}

.page-about .about-device__icon svg {
  width: 100%;
  height: 100%;
  display: block;
}

.page-about .about-device__title {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  margin: 0;
  color: var(--about-paper);
}

.page-about .about-device__desc {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.78);
}

.page-about .about-device__features {
  margin: 0.3rem 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.page-about .about-device__features li {
  position: relative;
  padding-left: 1.2rem;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.9);
}

.page-about .about-device__features li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.5em;
  width: 0.55rem;
  height: 0.55rem;
  border-radius: 50%;
  background: var(--about-neon);
  border: 1px solid var(--about-ink);
}

.page-about .about-section--search .about-section__lead {
  margin-bottom: 1.8rem;
}

.page-about .about-search {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1rem;
}

.page-about .about-search__step {
  position: relative;
  background: var(--about-paper);
  border: 2px solid var(--about-ink);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.2rem 1.3rem;
  box-shadow: 5px 5px 0 rgba(17, 17, 17, 0.09);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.page-about .about-search__step:hover {
  transform: translateY(-3px);
  box-shadow: 7px 7px 0 rgba(17, 17, 17, 0.12);
}

.page-about .about-search__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.2rem;
  height: 2.2rem;
  border-radius: 50%;
  background: var(--about-hot);
  color: var(--about-ink);
  border: 2px solid var(--about-ink);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.05rem;
  position: absolute;
  top: -0.9rem;
  left: 1rem;
}

.page-about .about-search__title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.05rem;
  margin: 0.4rem 0 0.5rem;
  color: var(--about-ink);
}

.page-about .about-search__desc {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.65;
  color: rgba(17, 17, 17, 0.82);
}

@media (min-width: 640px) {
  .page-about .about-hero {
    padding: 2.6rem 1.5rem 3rem;
  }

  .page-about .about-scale {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-scale__total {
    grid-column: span 3;
    min-height: auto;
    flex-direction: row;
    align-items: baseline;
    gap: 0.8rem;
    flex-wrap: wrap;
  }

  .page-about .about-scale__total-num {
    font-size: 2.6rem;
  }

  .page-about .about-update__flow {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-device {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-device__card--cross {
    grid-column: span 2;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__layout {
    grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
    gap: 3rem;
  }

  .page-about .about-hero__stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-section {
    padding: 3.6rem 0;
  }

  .page-about .about-taxo {
    grid-template-columns: minmax(0, 1.2fr) minmax(280px, 0.8fr);
  }

  .page-about .about-figure--taxo {
    margin-top: 0;
  }

  .page-about .about-update__flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1rem;
  }

  .page-about .about-update__step {
    flex-direction: column;
    gap: 0.6rem;
  }

  .page-about .about-version__item {
    padding-left: 1.4rem;
  }

  .page-about .about-version__item:hover {
    background: rgba(255, 255, 255, 0.16);
    border-radius: var(--radius-md);
  }

  .page-about .about-device {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-device__card--cross {
    grid-column: auto;
  }

  .page-about .about-search {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-search__step {
    padding-top: 1.6rem;
  }
}