.page-about {
  --about-blue: #0d4a6e;
  --about-green: #00c48c;
  --about-gold: #f0a500;
  --about-paper: #f5f0e8;
  --about-ink: #1a1a1a;
  --about-gray: #333333;
  --about-line: #e8e0d4;
  --about-white: #ffffff;
  --about-sky: #e8f4f8;
  --about-red: #e74c3c;
  --about-font-title: Impact, 'Arial Black', 'Noto Sans SC Black', sans-serif;
  --about-font-body: 'Noto Sans SC', 'Microsoft YaHei', sans-serif;
  --about-font-data: ui-monospace, SFMono-Regular, Consolas, 'Liberation Mono', monospace;
  background-color: var(--about-paper);
  color: var(--about-ink);
  padding: 0;
}

.page-about .about-shell {
  display: flex;
  min-height: 100vh;
}

.page-about .about-rail {
  background: var(--about-blue);
  width: 280px;
  flex-shrink: 0;
  padding: 48px 32px;
  position: sticky;
  top: 0;
  height: 100vh;
  display: flex;
  flex-direction: column;
  clip-path: polygon(0 0, 100% 0, 88% 100%, 0 100%);
  margin-right: -28px;
  z-index: 5;
}

.page-about .about-rail__inner {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.page-about .about-rail__kick {
  font-family: var(--about-font-data);
  font-size: 0.75rem;
  color: var(--about-green);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 40px;
}

.page-about .about-rail__brand-num {
  font-family: var(--about-font-title);
  font-size: 5rem;
  line-height: 1;
  color: var(--about-white);
}

.page-about .about-rail__brand-num-label {
  color: var(--about-green);
  font-size: 1rem;
  font-weight: 600;
  margin-top: 6px;
  letter-spacing: 0.08em;
}

.page-about .about-rail__line {
  width: 48px;
  height: 3px;
  background: var(--about-gold);
  margin: 32px 0;
  transform: skewX(-30deg);
}

.page-about .about-rail__stat {
  display: flex;
  flex-direction: column;
  margin-bottom: 20px;
}

.page-about .about-rail__stat-num {
  font-family: var(--about-font-data);
  font-size: 2rem;
  font-weight: 700;
  color: var(--about-gold);
}

.page-about .about-rail__stat-txt {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.8);
  margin-top: 2px;
}

.page-about .about-rail__version {
  margin-top: auto;
  font-family: var(--about-font-data);
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.3);
  display: inline-block;
  padding: 6px 12px;
  transform: skewX(-8deg);
  align-self: flex-start;
}

.page-about .about-main {
  flex: 1;
  padding: 32px 48px 64px;
  min-width: 0;
}

.page-about .breadcrumb {
  font-size: 0.85rem;
  color: var(--about-gray);
  margin-bottom: 32px;
  display: flex;
  gap: 8px;
  align-items: center;
}

.page-about .breadcrumb a {
  color: var(--about-blue);
  text-decoration: none;
  font-weight: 600;
}

.page-about .breadcrumb a:hover {
  color: var(--about-green);
}

.page-about .about-hero__frame {
  position: relative;
  padding-left: 48px;
  border-left: 4px solid var(--about-green);
  margin-bottom: 32px;
}

.page-about .about-hero__frame::before {
  content: '';
  position: absolute;
  left: -4px;
  top: 0;
  width: 4px;
  height: 64px;
  background: var(--about-gold);
}

.page-about .about-hero__eyebrow {
  font-family: var(--about-font-data);
  font-size: 1rem;
  color: var(--about-blue);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.page-about .about-hero h1 {
  font-family: var(--about-font-title);
  font-size: clamp(2rem, 4vw, 3.4rem);
  line-height: 1.15;
  margin: 0 0 20px;
  letter-spacing: 0.02em;
}

.page-about .about-hero__lead {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--about-gray);
  max-width: 680px;
  margin-bottom: 28px;
}

.page-about .about-hero__actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.page-about .btn {
  display: inline-block;
  padding: 12px 24px;
  font-family: var(--about-font-body);
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  transform: skewX(-6deg);
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
  border: 2px solid transparent;
}

.page-about .btn > span,
.page-about .btn {
  display: inline-block;
}

.page-about .btn--gold {
  background: var(--about-gold);
  color: var(--about-ink);
  border-color: var(--about-gold);
}

.page-about .btn--gold:hover {
  background: #d48f00;
  border-color: #d48f00;
}

.page-about .btn--ghost {
  background: transparent;
  color: var(--about-blue);
  border-color: var(--about-blue);
}

.page-about .btn--ghost:hover {
  background: var(--about-blue);
  color: var(--about-white);
}

.page-about .about-hero__meta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 24px;
}

.page-about .tag {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 2px;
  background: var(--about-sky);
  color: var(--about-blue);
  border-left: 3px solid var(--about-blue);
}

.page-about .tag--gold {
  background: #fdf3d0;
  color: #b17700;
  border-left-color: var(--about-gold);
}

.page-about .about-section {
  margin-top: 80px;
}

.page-about .section-head {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  margin-bottom: 36px;
  border-bottom: 2px solid var(--about-line);
  padding-bottom: 16px;
}

.page-about .section-head--light {
  border-bottom-color: rgba(255, 255, 255, 0.2);
}

.page-about .section-head__index {
  font-family: var(--about-font-data);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--about-gold);
  background: var(--about-ink);
  padding: 6px 12px;
  transform: skewX(-10deg);
  flex-shrink: 0;
  white-space: nowrap;
}

.page-about .section-head h2 {
  font-family: var(--about-font-title);
  font-size: clamp(1.5rem, 2.4vw, 2rem);
  margin: 0;
  letter-spacing: 0.02em;
}

.page-about .section-head p {
  color: var(--about-gray);
  font-size: 0.95rem;
  margin: 6px 0 0;
}

.page-about .slant-line {
  display: block;
  width: 80px;
  height: 2px;
  background: var(--about-green);
  transform: skewX(-30deg);
  margin-top: 8px;
  margin-left: auto;
  flex-shrink: 0;
}

.page-about .about-origin__grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
}

.page-about .about-origin__text p {
  font-size: 0.95rem;
  line-height: 1.8;
  color: var(--about-gray);
  margin: 0 0 16px;
}

.page-about .tick-list {
  list-style: none;
  padding: 0;
  margin: 24px 0 0;
}

.page-about .tick-list li {
  position: relative;
  padding-left: 22px;
  font-size: 0.95rem;
  font-weight: 500;
  margin-bottom: 10px;
  line-height: 1.6;
}

.page-about .tick-list li::before {
  content: '';
  position: absolute;
  left: 4px;
  top: 8px;
  width: 8px;
  height: 8px;
  background: var(--about-green);
  transform: skewX(-15deg);
}

.page-about .media-frame {
  position: relative;
  overflow: hidden;
  line-height: 0;
}

.page-about .media-frame img {
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  display: block;
}

.page-about .media-frame::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 32px;
  height: 32px;
  background: var(--about-gold);
  clip-path: polygon(0 0, 100% 0, 100% 100%);
}

.page-about .media-frame figcaption {
  font-size: 0.8rem;
  color: var(--about-gray);
  padding: 12px 0 0;
  line-height: 1.4;
}

.page-about .about-origin__media img {
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-about .about-data {
  background: var(--about-blue);
  margin-left: -48px;
  margin-right: -48px;
  padding: 48px 48px 56px;
  color: #fff;
  position: relative;
}

.page-about .about-data::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 120px;
  height: 4px;
  background: var(--about-green);
}

.page-about .about-data .section-head p {
  color: rgba(255, 255, 255, 0.75);
}

.page-about .about-data .slant-line {
  background: var(--about-gold);
}

.page-about .about-data__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.page-about .about-data__stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.page-about .stat-card--transparent {
  background: rgba(255, 255, 255, 0.06);
  border-left: 3px solid var(--about-green);
  padding: 20px;
}

.page-about .stat-value {
  display: block;
  font-family: var(--about-font-title);
  font-size: 2.6rem;
  color: var(--about-gold);
  line-height: 1;
  margin-bottom: 6px;
}

.page-about .stat-label {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.8);
}

.page-about .about-data__content p {
  font-size: 0.95rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 16px;
}

.page-about .about-data__media {
  margin-top: 40px;
}

.page-about .about-data__media figcaption {
  color: rgba(255, 255, 255, 0.7);
}

.page-about .about-tech__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.page-about .about-tech__item {
  background: var(--about-white);
  padding: 32px 28px;
  position: relative;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  border-top: 3px solid var(--about-blue);
  box-shadow: 0 4px 16px rgba(26, 26, 26, 0.06);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.page-about .about-tech__item:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 28px rgba(26, 26, 26, 0.12);
}

.page-about .about-tech__code {
  font-family: var(--about-font-data);
  font-size: 1rem;
  font-weight: 700;
  background: var(--about-blue);
  color: var(--about-white);
  display: inline-block;
  padding: 6px 14px;
  transform: skewX(-8deg);
  margin-bottom: 16px;
}

.page-about .about-tech__item h3 {
  font-size: 1.05rem;
  margin: 0 0 10px;
  line-height: 1.4;
}

.page-about .about-tech__item p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--about-gray);
  margin: 0;
}

.page-about .about-tech__sync {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
}

.page-about .about-tech__note {
  background: var(--about-sky);
  padding: 28px;
  border-left: 4px solid var(--about-blue);
}

.page-about .about-tech__note p {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--about-gray);
  margin: 0 0 16px;
}

.page-about .about-road__wrap {
  position: relative;
}

.page-about .about-road__line {
  position: absolute;
  left: 10px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--about-green) 0%, var(--about-blue) 100%);
  transform: skewX(-15deg);
}

.page-about .about-road__timeline {
  list-style: none;
  padding: 0;
  margin: 0;
  position: relative;
}

.page-about .timeline-item {
  position: relative;
  padding-left: 48px;
  margin-bottom: 40px;
}

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

.page-about .timeline-item__dot {
  position: absolute;
  left: 0;
  top: 6px;
  width: 22px;
  height: 22px;
  background: var(--about-paper);
  border: 4px solid var(--about-green);
  border-radius: 0;
  transform: rotate(45deg);
  transition: background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.page-about .timeline-item:hover .timeline-item__dot {
  background: var(--about-gold);
  border-color: var(--about-gold);
  transform: rotate(45deg) scale(1.15);
}

.page-about .timeline-item__body {
  background: var(--about-white);
  padding: 24px 28px;
  box-shadow: 0 4px 16px rgba(26, 26, 26, 0.05);
  border-right: 3px solid var(--about-blue);
}

.page-about .timeline-item__body h3 {
  font-size: 1.1rem;
  margin: 10px 0 8px;
}

.page-about .timeline-item__body p {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--about-gray);
  margin: 0;
}

.page-about .about-guide__inner {
  background: var(--about-ink);
  padding: 48px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 40px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%);
}

.page-about .about-guide__inner .section-head__index {
  background: var(--about-gold);
  color: var(--about-ink);
}

.page-about .about-guide__inner h2 {
  font-family: var(--about-font-title);
  font-size: 1.8rem;
  color: var(--about-white);
  margin: 8px 0 8px;
}

.page-about .about-guide__inner p {
  color: rgba(255, 255, 255, 0.75);
  font-size: 0.95rem;
  line-height: 1.7;
  margin: 0;
}

.page-about .about-guide__links {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  flex-shrink: 0;
}

.page-about .about-guide__links .btn--ghost {
  border-color: rgba(255, 255, 255, 0.5);
  color: var(--about-white);
}

.page-about .about-guide__links .btn--ghost:hover {
  border-color: var(--about-green);
  background: var(--about-green);
  color: var(--about-ink);
}

@media (max-width: 960px) {
  .page-about .about-shell {
    flex-direction: column;
  }

  .page-about .about-rail {
    width: 100%;
    height: auto;
    position: static;
    clip-path: none;
    margin-right: 0;
    padding: 24px;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .page-about .about-rail__inner {
    flex-direction: row;
    align-items: center;
    gap: 24px;
    width: 100%;
    height: auto;
  }

  .page-about .about-rail__kick {
    margin-bottom: 0;
    margin-right: auto;
  }

  .page-about .about-rail__brand-num {
    font-size: 2.4rem;
  }

  .page-about .about-rail__brand-num-label {
    font-size: 0.8rem;
  }

  .page-about .about-rail__line {
    margin: 0;
    transform: skewX(-30deg) rotate(90deg);
    height: 24px;
    width: 3px;
  }

  .page-about .about-rail__version {
    margin-top: 0;
  }

  .page-about .about-rail__stat {
    display: none;
  }

  .page-about .about-main {
    padding: 24px 20px 48px;
  }

  .page-about .about-origin__grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .page-about .about-data {
    margin-left: -20px;
    margin-right: -20px;
    padding: 36px 20px 44px;
  }

  .page-about .about-data__grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

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

  .page-about .about-tech__sync {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .page-about .about-guide__inner {
    flex-direction: column;
    align-items: flex-start;
    padding: 32px 24px;
  }
}

@media (max-width: 620px) {
  .page-about .about-rail__inner {
    flex-wrap: wrap;
    gap: 12px;
  }

  .page-about .about-rail__kick {
    font-size: 0.65rem;
    margin-right: auto;
  }

  .page-about .about-rail__brand-num {
    font-size: 1.8rem;
  }

  .page-about .about-rail__brand-num-label {
    font-size: 0.7rem;
  }

  .page-about .about-rail__line {
    display: none;
  }

  .page-about .about-rail__version {
    font-size: 0.7rem;
    padding: 4px 8px;
  }

  .page-about .breadcrumb {
    font-size: 0.75rem;
    margin-bottom: 20px;
  }

  .page-about .about-hero__frame {
    padding-left: 20px;
  }

  .page-about .about-hero h1 {
    font-size: 1.9rem;
  }

  .page-about .about-hero__lead {
    font-size: 0.9rem;
  }

  .page-about .about-hero__actions {
    flex-direction: column;
    gap: 12px;
  }

  .page-about .about-hero__actions .btn {
    text-align: center;
  }

  .page-about .section-head {
    flex-wrap: wrap;
    gap: 12px;
  }

  .page-about .section-head p {
    font-size: 0.85rem;
  }

  .page-about .slant-line {
    display: none;
  }

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

  .page-about .stat-value {
    font-size: 2rem;
  }

  .page-about .about-origin__text p,
  .page-about .about-tech__item p,
  .page-about .about-data__content p {
    font-size: 0.875rem;
  }

  .page-about .timeline-item {
    padding-left: 40px;
  }

  .page-about .timeline-item__body {
    padding: 18px 16px;
  }

  .page-about .timeline-item__body h3 {
    font-size: 1rem;
  }

  .page-about .timeline-item__body p {
    font-size: 0.85rem;
  }

  .page-about .about-guide__inner h2 {
    font-size: 1.4rem;
  }

  .page-about .about-guide__links {
    flex-direction: column;
    width: 100%;
  }

  .page-about .about-guide__links .btn {
    text-align: center;
  }
}