.page-about {
  --about-yellow: #FFD54F;
  --about-cyan: #26C6DA;
  --about-coral: #FF7043;
  --about-purple: #AB47BC;
  --about-ink: #212121;
  --about-paper: #FFFFFF;
  --about-bg: #F5F0E6;
  --about-gray: #BDBDBD;
  --about-red: #E53935;
  --about-shadow: 6px 6px 0 var(--about-ink);
  --about-radius: 8px;
  background: var(--about-bg);
  color: var(--about-ink);
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

.about-hero {
  background: var(--about-ink);
  padding: 32px 20px 0;
  position: relative;
  overflow: hidden;
}

.about-hero__inner {
  max-width: 1280px;
  margin: 0 auto;
}

.about-hero .breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 24px;
}

.about-hero .breadcrumb a {
  color: var(--about-yellow);
  text-decoration: none;
  font-weight: 700;
}

.about-hero .breadcrumb a:hover,
.about-hero .breadcrumb a:focus-visible {
  text-decoration: underline;
  outline: none;
}

.about-hero__content {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.about-hero__text {
  flex: 1;
}

.about-hero__kicker {
  display: inline-block;
  background: var(--about-yellow);
  color: var(--about-ink);
  font-size: 13px;
  font-weight: 800;
  padding: 4px 12px;
  border-radius: 4px;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.about-hero__text h1 {
  font-size: 28px;
  font-weight: 900;
  line-height: 1.3;
  color: var(--about-paper);
  margin: 0 0 12px;
  letter-spacing: 0.02em;
  border-left: 6px solid var(--about-yellow);
  padding-left: 16px;
}

.about-hero__text p {
  font-size: 15px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.85);
  margin: 0;
  max-width: 640px;
}

.about-hero__visual {
  border-radius: var(--about-radius) var(--about-radius) 0 0;
  overflow: hidden;
  border: 3px solid var(--about-paper);
  border-bottom: none;
  position: relative;
  max-height: 300px;
}

.about-hero__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  max-height: 300px;
}

.about-hero__badge {
  position: absolute;
  top: 16px;
  right: 16px;
  background: var(--about-red);
  color: var(--about-paper);
  font-weight: 900;
  font-size: 18px;
  padding: 8px 16px;
  border-radius: 4px;
  box-shadow: 4px 4px 0 rgba(255, 255, 255, 0.25);
  letter-spacing: 0.05em;
}

.about-layout {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px 60px;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.about-sidebar {
  background: var(--about-paper);
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  box-shadow: var(--about-shadow);
  margin-top: 32px;
  padding: 20px;
  position: sticky;
  top: 100px;
  z-index: 5;
}

.about-sidebar__inner {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.about-sidebar__label {
  font-size: 12px;
  font-weight: 900;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--about-ink);
  border-bottom: 3px solid var(--about-yellow);
  display: inline-block;
  padding-bottom: 4px;
  width: fit-content;
}

.about-sidebar__nav {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.about-sidebar__link {
  display: block;
  padding: 8px 12px;
  font-size: 14px;
  font-weight: 700;
  color: var(--about-ink);
  text-decoration: none;
  border-radius: 4px;
  border-left: 3px solid transparent;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.about-sidebar__link:hover,
.about-sidebar__link:focus-visible {
  background: var(--about-yellow);
  border-left-color: var(--about-ink);
  outline: none;
}

.about-sidebar__links {
  display: flex;
  flex-direction: column;
  gap: 4px;
  border-top: 1px solid var(--about-gray);
  padding-top: 14px;
}

.about-content {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.about-section {
  padding: 44px 0;
  border-bottom: 3px solid var(--about-ink);
  scroll-margin-top: 110px;
  position: relative;
}

.about-section:last-of-type {
  border-bottom: none;
}

.about-section--overview {
  background: var(--about-bg);
}

.about-section--column {
  background: var(--about-yellow);
  margin: 0 -20px;
  padding-left: 20px;
  padding-right: 20px;
  border-top: 3px solid var(--about-ink);
}

.about-section--update {
  background: var(--about-cyan);
  margin: 0 -20px;
  padding-left: 20px;
  padding-right: 20px;
  border-top: 3px solid var(--about-ink);
}

.about-section--search {
  background: var(--about-bg);
}

.about-section__num {
  position: absolute;
  top: 20px;
  right: 0;
  font-size: 56px;
  font-weight: 900;
  color: rgba(33, 33, 33, 0.08);
  line-height: 1;
  user-select: none;
  letter-spacing: 0.02em;
}

.about-section__header {
  position: relative;
  z-index: 1;
  margin-bottom: 28px;
}

.about-section__header h2 {
  font-size: 26px;
  font-weight: 900;
  margin: 0 0 8px;
  letter-spacing: 0.02em;
  display: inline-block;
  background: var(--about-paper);
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  padding: 8px 16px;
  box-shadow: 4px 4px 0 var(--about-ink);
}

.about-section__header p {
  font-size: 14px;
  color: rgba(33, 33, 33, 0.7);
  margin: 12px 0 0;
  font-weight: 500;
}

.about-overview-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  position: relative;
  z-index: 1;
}

.about-stat-card {
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  box-shadow: 5px 5px 0 var(--about-ink);
  padding: 0;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.about-stat-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 var(--about-ink);
}

.about-stat-card--yellow {
  background: var(--about-yellow);
}

.about-stat-card--cyan {
  background: var(--about-cyan);
}

.about-stat-card--coral {
  background: var(--about-coral);
}

.about-stat-card--purple {
  background: var(--about-purple);
}

.about-stat-card--paper {
  background: var(--about-paper);
}

.about-stat-card__inner {
  padding: 20px 18px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.about-stat-card__label {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  opacity: 0.8;
}

.about-stat-card__value {
  font-size: 40px;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 0.03em;
  font-variant-numeric: tabular-nums;
}

.about-stat-card__note {
  font-size: 13px;
  font-weight: 500;
  opacity: 0.75;
}

.about-stat-card--purple .about-stat-card__value,
.about-stat-card--purple .about-stat-card__label,
.about-stat-card--purple .about-stat-card__note {
  color: var(--about-paper);
}

.about-overview-note {
  margin-top: 24px;
  background: var(--about-paper);
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  padding: 20px;
  box-shadow: 5px 5px 0 var(--about-ink);
  position: relative;
  z-index: 1;
}

.about-overview-note p {
  font-size: 14px;
  line-height: 1.9;
  margin: 0;
  font-weight: 500;
}

.about-column-wrap {
  display: flex;
  flex-direction: column;
  gap: 24px;
  position: relative;
  z-index: 1;
}

.about-tree-root {
  background: var(--about-ink);
  color: var(--about-paper);
  border-radius: var(--about-radius);
  padding: 16px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
}

.about-tree-root__label {
  font-size: 16px;
  font-weight: 900;
}

.about-tree-root__count {
  background: var(--about-yellow);
  color: var(--about-ink);
  font-size: 13px;
  font-weight: 900;
  padding: 4px 12px;
  border-radius: 999px;
}

.about-tree-branches {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.about-tree-branch {
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  overflow: hidden;
  background: var(--about-paper);
}

.about-tree-branch__head {
  padding: 14px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 2px solid var(--about-ink);
  gap: 8px;
  flex-wrap: wrap;
}

.about-tree-branch--yellow .about-tree-branch__head {
  background: var(--about-yellow);
}

.about-tree-branch--cyan .about-tree-branch__head {
  background: var(--about-cyan);
}

.about-tree-branch--coral .about-tree-branch__head {
  background: var(--about-coral);
}

.about-tree-branch--purple .about-tree-branch__head {
  background: var(--about-purple);
}

.about-tree-branch--paper .about-tree-branch__head {
  background: var(--about-paper);
}

.about-tree-branch__name {
  font-size: 15px;
  font-weight: 900;
}

.about-tree-branch__count {
  font-size: 12px;
  font-weight: 800;
  background: var(--about-ink);
  color: var(--about-paper);
  padding: 4px 10px;
  border-radius: 999px;
  white-space: nowrap;
}

.about-tree-branch__children {
  margin: 0;
  padding: 12px 16px;
  list-style: none;
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
}

.about-tree-branch__children li {
  font-size: 13px;
  padding-left: 14px;
  position: relative;
  font-weight: 500;
}

.about-tree-branch__children li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  background: var(--about-ink);
  border-radius: 2px;
}

.about-column-img {
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  overflow: hidden;
  box-shadow: 5px 5px 0 var(--about-ink);
}

.about-column-img img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 300px;
  object-fit: cover;
}

.about-update-layout {
  display: flex;
  flex-direction: column;
  gap: 24px;
  position: relative;
  z-index: 1;
}

.about-timeline-item {
  padding: 18px 20px;
  border-left: 6px solid var(--about-ink);
  background: var(--about-paper);
  border-radius: 0 var(--about-radius) var(--about-radius) 0;
  margin-bottom: 16px;
  box-shadow: 4px 4px 0 rgba(33, 33, 33, 0.4);
}

.about-timeline-item:last-child {
  margin-bottom: 0;
}

.about-timeline-item__badge {
  display: inline-block;
  background: var(--about-ink);
  color: var(--about-paper);
  font-size: 11px;
  font-weight: 800;
  padding: 3px 10px;
  border-radius: 999px;
  letter-spacing: 0.05em;
  margin-bottom: 10px;
}

.about-timeline-item h3 {
  font-size: 16px;
  font-weight: 900;
  margin: 0 0 6px;
  color: var(--about-ink);
  border-left: 4px solid var(--about-yellow);
  padding-left: 10px;
}

.about-timeline-item p {
  font-size: 14px;
  line-height: 1.8;
  margin: 0;
  opacity: 0.85;
}

.about-update-visual {
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  overflow: hidden;
  box-shadow: 5px 5px 0 var(--about-ink);
}

.about-update-visual img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 260px;
  object-fit: cover;
}

.about-batch-strip {
  margin-top: 28px;
  background: var(--about-paper);
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  box-shadow: 5px 5px 0 var(--about-ink);
  position: relative;
  z-index: 1;
}

.about-batch-strip__label {
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0.05em;
  color: var(--about-ink);
}

.about-batch-strip__item {
  background: var(--about-gray);
  color: var(--about-ink);
  font-size: 13px;
  font-weight: 800;
  padding: 4px 14px;
  border-radius: 999px;
}

.about-batch-strip__item--new {
  background: var(--about-red);
  color: var(--about-paper);
  position: relative;
}

.about-batch-strip__note {
  font-size: 12px;
  font-weight: 700;
  color: var(--about-ink);
  opacity: 0.65;
  margin-left: auto;
  background: var(--about-yellow);
  padding: 4px 10px;
  border-radius: 4px;
}

.about-search-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  position: relative;
  z-index: 1;
}

.about-search-col {
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  overflow: hidden;
  box-shadow: 5px 5px 0 var(--about-ink);
}

.about-search-col--cyan {
  background: var(--about-cyan);
}

.about-search-col--coral {
  background: var(--about-coral);
}

.about-search-col__title {
  display: block;
  padding: 14px 18px;
  background: var(--about-ink);
  color: var(--about-paper);
  font-size: 16px;
  font-weight: 900;
  letter-spacing: 0.05em;
  border-bottom: 3px solid var(--about-ink);
}

.about-search-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.about-search-list__item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  border-bottom: 1px solid rgba(33, 33, 33, 0.15);
}

.about-search-list__item:last-child {
  border-bottom: none;
}

.about-search-list__tag {
  background: var(--about-paper);
  border: 2px solid var(--about-ink);
  border-radius: 4px;
  font-size: 12px;
  font-weight: 900;
  padding: 4px 10px;
  white-space: nowrap;
  flex-shrink: 0;
}

.about-search-list__text {
  font-size: 13px;
  font-weight: 600;
  line-height: 1.6;
}

.about-nav-block {
  margin-top: 32px;
  padding: 24px;
  background: var(--about-ink);
  border-radius: var(--about-radius);
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: 16px;
  align-items: flex-start;
}

.about-nav-block__label {
  font-size: 14px;
  font-weight: 900;
  color: var(--about-yellow);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.about-nav-block__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.about-nav-block .btn {
  font-size: 14px;
  font-weight: 800;
  padding: 10px 20px;
  border: 3px solid var(--about-ink);
  border-radius: var(--about-radius);
  text-decoration: none;
  display: inline-block;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  box-shadow: 4px 4px 0 rgba(255, 255, 255, 0.2);
}

.about-nav-block .btn:hover,
.about-nav-block .btn:focus-visible {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 rgba(255, 255, 255, 0.25);
  outline: none;
}

.about-nav-block .btn--yellow {
  background: var(--about-yellow);
  color: var(--about-ink);
}

.about-nav-block .btn--cyan {
  background: var(--about-cyan);
  color: var(--about-ink);
}

.about-nav-block .btn--primary {
  background: var(--about-coral);
  color: var(--about-paper);
}

@media (min-width: 768px) {
  .about-hero {
    padding: 48px 32px 0;
  }

  .about-hero__text h1 {
    font-size: 36px;
  }

  .about-hero__text p {
    font-size: 17px;
  }

  .about-overview-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .about-stat-card__value {
    font-size: 48px;
  }

  .about-tree-branches {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-tree-root__label {
    font-size: 20px;
  }

  .about-section {
    padding: 56px 0;
  }

  .about-section--column,
  .about-section--update {
    margin-left: -32px;
    margin-right: -32px;
    padding-left: 32px;
    padding-right: 32px;
  }

  .about-timeline-item {
    padding: 22px 24px;
  }

  .about-search-grid {
    grid-template-columns: 1fr 1fr;
  }

  .about-update-layout {
    flex-direction: column;
  }
}

@media (min-width: 1024px) {
  .about-hero__content {
    flex-direction: row;
    align-items: flex-end;
  }

  .about-hero__visual {
    width: 50%;
    max-height: 320px;
  }

  .about-layout {
    flex-direction: row;
    align-items: flex-start;
    gap: 32px;
    padding-left: 32px;
    padding-right: 32px;
  }

  .about-sidebar {
    width: 260px;
    flex-shrink: 0;
    margin-top: 48px;
  }

  .about-content {
    flex: 1;
    min-width: 0;
  }

  .about-update-layout {
    flex-direction: row;
    align-items: stretch;
  }

  .about-update-timeline {
    flex: 1;
  }

  .about-update-visual {
    width: 40%;
    flex-shrink: 0;
  }

  .about-update-visual img {
    height: 100%;
    max-height: none;
    min-height: 320px;
  }

  .about-column-wrap {
    flex-direction: row;
    align-items: flex-start;
  }

  .about-column-tree {
    flex: 1;
  }

  .about-column-img {
    width: 40%;
    flex-shrink: 0;
  }

  .about-column-img img {
    height: 100%;
    max-height: none;
    min-height: 480px;
  }

  .about-section__num {
    font-size: 80px;
  }
}

@media (min-width: 1280px) {
  .about-hero__inner {
    max-width: 1280px;
  }
}