.page-about {
  --about-charcoal: #111111;
  --about-deep: #0a1a30;
  --about-blue: #1b3a5c;
  --about-orange: #ff6b1a;
  --about-cream: #f5efe6;
  --about-gray: #8ba8c6;
  --about-moss: #6b8e6b;
  --about-terracotta: #c47c6f;
  --about-white: #ffffff;
  --about-mono: "Roboto Mono", "Courier New", monospace;
  --about-clip: 24px;
  background: var(--about-deep);
  color: var(--about-cream);
  font-family: "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
  line-height: 1.7;
  overflow-x: hidden;
}

.page-about .container {
  max-width: 1200px;
  margin: 0 auto;
  padding-left: 20px;
  padding-right: 20px;
  box-sizing: border-box;
}

.page-about a {
  color: var(--about-orange);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 107, 26, 0.35);
  transition: color 0.2s ease, border-color 0.2s ease;
}

.page-about a:hover {
  color: var(--about-cream);
  border-bottom-color: var(--about-cream);
}

.page-about .breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--about-mono);
  font-size: 13px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 28px 0 0;
  color: var(--about-gray);
}

.page-about .breadcrumb a {
  color: var(--about-gray);
  border-bottom: none;
}

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

.page-about .breadcrumb-sep {
  color: var(--about-orange);
  font-family: var(--about-mono);
}

.page-about .about-hero {
  position: relative;
  padding-bottom: 56px;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 42%;
  height: 100%;
  background: linear-gradient(135deg, transparent 55%, rgba(27, 58, 92, 0.5) 55%), repeating-linear-gradient(45deg, rgba(139, 168, 198, 0.06) 0 1px, transparent 1px 8px);
  clip-path: polygon(18% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  position: relative;
  z-index: 1;
  padding-top: 32px;
}

.page-about .about-hero-copy {
  max-width: 680px;
}

.page-about .eyebrow-index {
  font-family: var(--about-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--about-orange);
  margin: 0 0 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .eyebrow-index::after {
  content: "";
  width: 32px;
  height: 1px;
  background: var(--about-orange);
  display: inline-block;
}

.page-about .about-hero h1 {
  font-size: 30px;
  line-height: 1.25;
  font-weight: 900;
  letter-spacing: 0.02em;
  margin: 0 0 20px;
  color: var(--about-cream);
  max-width: 640px;
}

.page-about .about-hero-lead {
  font-size: 16px;
  line-height: 1.8;
  color: var(--about-gray);
  max-width: 600px;
  margin: 0 0 28px;
}

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

.page-about .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  font-size: 15px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
  text-decoration: none;
  border-bottom: none;
  letter-spacing: 0.02em;
  font-family: "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
}

.page-about .btn-primary {
  background: var(--about-orange);
  color: var(--about-deep);
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
}

.page-about .btn-primary:hover {
  background: var(--about-cream);
  color: var(--about-deep);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(255, 107, 26, 0.25);
}

.page-about .btn-outline {
  background: transparent;
  color: var(--about-cream);
  border: 1px solid var(--about-gray);
  clip-path: polygon(0 0, calc(100% - 12px) 0, 100% 12px, 100% 100%, 12px 100%, 0 calc(100% - 12px));
}

.page-about .btn-outline:hover {
  border-color: var(--about-orange);
  color: var(--about-orange);
  transform: translateY(-2px);
}

.page-about .about-hero-visual {
  display: none;
}

.page-about .about-core {
  padding: 48px 0;
  position: relative;
}

.page-about .about-core::before {
  content: "";
  position: absolute;
  left: 0;
  top: 20px;
  bottom: 20px;
  width: 4px;
  background: linear-gradient(to bottom, var(--about-orange) 0 40px, transparent 40px);
  opacity: 0.4;
}

.page-about .section-head {
  margin-bottom: 32px;
  position: relative;
}

.page-about .section-head h2 {
  font-size: 28px;
  line-height: 1.2;
  font-weight: 900;
  margin: 0;
  letter-spacing: 0.02em;
  color: var(--about-cream);
}

.page-about .core-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

.page-about .core-copy {
  font-size: 15px;
  line-height: 1.8;
  color: var(--about-gray);
}

.page-about .core-copy p {
  margin: 0 0 18px;
}

.page-about .core-copy strong {
  color: var(--about-orange);
  font-weight: 700;
}

.page-about .core-stat {
  font-size: 17px;
}

.page-about .core-stat-num {
  color: var(--about-orange);
  font-family: var(--about-mono);
  font-weight: 700;
  font-size: 22px;
}

.page-about .core-figure {
  margin: 0;
  position: relative;
}

.page-about .core-img {
  width: 100%;
  max-width: 100%;
  height: auto;
  display: block;
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
  object-fit: cover;
  aspect-ratio: 1200 / 600;
}

.page-about .core-figure figcaption {
  font-size: 13px;
  color: var(--about-gray);
  padding: 12px 4px 0;
  font-family: var(--about-mono);
  letter-spacing: 0.03em;
}

.page-about .core-facts {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin: 40px 0 0;
  padding: 0;
}

.page-about .core-fact-item {
  background: var(--about-blue);
  padding: 18px 16px;
  border-left: 3px solid var(--about-orange);
  margin: 0;
  transition: transform 0.2s ease;
}

.page-about .core-fact-item:hover {
  transform: translateX(4px);
}

.page-about .core-fact-item dt {
  font-family: var(--about-mono);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--about-gray);
  margin: 0 0 6px;
}

.page-about .core-fact-item dd {
  margin: 0;
  font-size: 24px;
  font-weight: 900;
  color: var(--about-cream);
}

.page-about .about-milestones {
  padding: 56px 0;
  position: relative;
  background: linear-gradient(180deg, rgba(27, 58, 92, 0.4) 0%, rgba(10, 26, 48, 0.8) 100%);
}

.page-about .about-milestones::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(to right, var(--about-orange) 0 80px, rgba(139, 168, 198, 0.2) 80px 100%);
}

.page-about .milestone-wrap {
  position: relative;
}

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

.page-about .milestone-line::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: repeating-linear-gradient(to bottom, var(--about-orange) 0 8px, transparent 8px 14px);
  opacity: 0.6;
}

.page-about .milestone-item {
  position: relative;
  padding-left: 40px;
  padding-bottom: 28px;
}

.page-about .milestone-item:last-child {
  padding-bottom: 0;
}

.page-about .milestone-marker {
  position: absolute;
  left: 0;
  top: 4px;
  display: flex;
  align-items: center;
  gap: 8px;
  z-index: 2;
}

.page-about .milestone-dot {
  width: 14px;
  height: 14px;
  background: var(--about-orange);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(255, 107, 26, 0.2);
  display: block;
}

.page-about .milestone-tag {
  font-family: var(--about-mono);
  font-size: 13px;
  color: var(--about-orange);
  letter-spacing: 0.06em;
  margin-left: 6px;
  background: var(--about-deep);
  padding: 2px 8px;
  border-left: 2px solid var(--about-orange);
}

.page-about .milestone-card {
  background: var(--about-blue);
  padding: 18px 16px;
  margin-top: 18px;
  transition: background-color 0.3s ease;
}

.page-about .milestone-card.clip-right {
  clip-path: polygon(0 0, calc(100% - var(--about-clip)) 0, 100% var(--about-clip), 100% 100%, 0 100%);
}

.page-about .milestone-card.clip-left {
  clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-clip) 100%, 0 calc(100% - var(--about-clip)));
}

.page-about .milestone-card:hover {
  background: #23486e;
}

.page-about .milestone-card h3 {
  font-size: 19px;
  font-weight: 900;
  color: var(--about-cream);
  margin: 0 0 10px;
}

.page-about .milestone-card p {
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-gray);
  margin: 0;
}

.page-about .milestone-detail {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: max-height 0.35s ease, opacity 0.35s ease, margin 0.3s ease;
  margin-top: 0;
}

.page-about .milestone-card[data-open="true"] .milestone-detail {
  max-height: 320px;
  opacity: 1;
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed rgba(255, 107, 26, 0.4);
}

.page-about .milestone-detail p {
  color: var(--about-cream);
  font-size: 14px;
}

.page-about .milestone-figure {
  margin: 40px 0 0;
  text-align: center;
}

.page-about .milestone-figure img {
  width: 100%;
  max-width: 800px;
  height: auto;
  display: block;
  margin: 0 auto;
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
  object-fit: cover;
  aspect-ratio: 800 / 600;
}

.page-about .about-credentials {
  padding: 56px 0;
}

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

.page-about .credential-card {
  background: var(--about-blue);
  padding: 24px 20px;
  position: relative;
  transition: transform 0.2s ease, background-color 0.3s ease;
}

.page-about .credential-card.clip-left {
  clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-clip) 100%, 0 calc(100% - var(--about-clip)));
}

.page-about .credential-card.clip-right {
  clip-path: polygon(0 0, calc(100% - var(--about-clip)) 0, 100% var(--about-clip), 100% 100%, 0 100%);
}

.page-about .credential-card:hover {
  transform: translateY(-4px);
  background: #23486e;
}

.page-about .credential-badge {
  margin-bottom: 16px;
}

.page-about .credential-badge svg {
  display: block;
}

.page-about .credential-card h3 {
  font-size: 18px;
  font-weight: 900;
  color: var(--about-cream);
  margin: 0 0 12px;
}

.page-about .credential-card p {
  font-size: 14px;
  line-height: 1.75;
  color: var(--about-gray);
  margin: 0;
}

.page-about .credential-figure {
  margin: 32px 0 0;
  text-align: center;
}

.page-about .credential-figure img {
  width: 100%;
  max-width: 400px;
  height: auto;
  display: block;
  margin: 0 auto;
  opacity: 0.9;
  border-radius: 50%;
  object-fit: cover;
  aspect-ratio: 1 / 1;
  border: 1px solid rgba(255, 107, 26, 0.25);
}

.page-about .about-promises {
  padding: 56px 0 64px;
  position: relative;
}

.page-about .about-promises::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(to right, transparent 0 20%, rgba(139, 168, 198, 0.3) 20% 80%, transparent 80%);
}

.page-about .promise-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.page-about .promise-item {
  background: var(--about-blue);
  overflow: hidden;
}

.page-about .promise-item.clip-right {
  clip-path: polygon(0 0, calc(100% - var(--about-clip)) 0, 100% var(--about-clip), 100% 100%, 0 100%);
}

.page-about .promise-item.clip-left {
  clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-clip) 100%, 0 calc(100% - var(--about-clip)));
}

.page-about .promise-toggle {
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  background: transparent;
  border: none;
  padding: 18px 16px;
  cursor: pointer;
  text-align: left;
  font-family: "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
  transition: background-color 0.2s ease;
}

.page-about .promise-toggle:hover {
  background: rgba(255, 107, 26, 0.08);
}

.page-about .promise-num {
  font-family: var(--about-mono);
  font-size: 13px;
  color: var(--about-orange);
  letter-spacing: 0.05em;
  min-width: 28px;
}

.page-about .promise-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--about-cream);
  flex: 1;
}

.page-about .promise-icon {
  font-family: var(--about-mono);
  font-size: 20px;
  color: var(--about-orange);
  transition: transform 0.3s ease;
  line-height: 1;
}

.page-about .promise-item[data-open="true"] .promise-icon {
  transform: rotate(45deg);
}

.page-about .promise-body {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: max-height 0.35s ease, opacity 0.35s ease;
}

.page-about .promise-item[data-open="true"] .promise-body {
  max-height: 320px;
  opacity: 1;
}

.page-about .promise-body p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--about-gray);
  margin: 0;
  padding: 0 16px 20px;
  border-top: 1px dashed rgba(255, 107, 26, 0.3);
  padding-top: 14px;
}

.page-about .promise-note {
  margin-top: 28px;
  padding: 20px;
  background: rgba(17, 17, 17, 0.5);
  border-left: 3px solid var(--about-moss);
}

.page-about .promise-note p {
  font-size: 14px;
  color: var(--about-gray);
  margin: 0;
  line-height: 1.8;
}

@media (min-width: 768px) {
  .page-about .about-hero {
    padding-bottom: 72px;
  }

  .page-about .about-hero h1 {
    font-size: 42px;
    line-height: 1.2;
  }

  .page-about .about-hero-lead {
    font-size: 18px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: 1.2fr 0.8fr;
    align-items: center;
    gap: 48px;
    padding-top: 40px;
  }

  .page-about .about-hero-visual {
    display: block;
  }

  .page-about .hero-track-svg {
    width: 100%;
    height: auto;
    max-width: 500px;
  }

  .page-about .about-core {
    padding: 64px 0;
  }

  .page-about .section-head h2 {
    font-size: 36px;
  }

  .page-about .core-layout {
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
  }

  .page-about .core-facts {
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-top: 48px;
  }

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

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

  .page-about .milestone-line::before {
    left: 24px;
  }

  .page-about .milestone-item {
    padding-left: 64px;
    padding-bottom: 36px;
  }

  .page-about .milestone-marker {
    left: 0;
  }

  .page-about .milestone-tag {
    font-size: 14px;
    margin-left: 10px;
  }

  .page-about .milestone-card {
    padding: 22px 24px;
    max-width: 720px;
  }

  .page-about .milestone-card h3 {
    font-size: 21px;
  }

  .page-about .milestone-card p {
    font-size: 15px;
  }

  .page-about .credential-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  .page-about .credential-card {
    padding: 28px 24px;
  }

  .page-about .about-promises {
    padding: 72px 0 80px;
  }

  .page-about .promise-list {
    gap: 16px;
  }

  .page-about .promise-toggle {
    padding: 20px 24px;
  }

  .page-about .promise-title {
    font-size: 18px;
  }

  .page-about .promise-body p {
    font-size: 15px;
    padding: 0 24px 24px;
    padding-top: 16px;
  }
}

@media (min-width: 1024px) {
  .page-about .container {
    padding-left: 32px;
    padding-right: 32px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 64px;
  }

  .page-about .about-hero h1 {
    font-size: 48px;
  }

  .page-about .core-facts {
    gap: 24px;
  }

  .page-about .credential-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 28px;
  }

  .page-about .milestone-item:nth-child(even) .milestone-card {
    margin-left: auto;
    margin-right: 40px;
  }

  .page-about .milestone-item:nth-child(odd) .milestone-card {
    margin-right: auto;
    margin-left: 40px;
  }

  .page-about .milestone-line::before {
    left: 50%;
    margin-left: -1px;
  }

  .page-about .milestone-item {
    padding-left: 0;
    width: 50%;
  }

  .page-about .milestone-item:nth-child(odd) {
    padding-right: 64px;
  }

  .page-about .milestone-item:nth-child(even) {
    margin-left: 50%;
    padding-left: 64px;
  }

  .page-about .milestone-item:nth-child(even) .milestone-marker {
    left: -7px;
  }

  .page-about .milestone-item:nth-child(odd) .milestone-marker {
    right: -7px;
    left: auto;
  }

  .page-about .milestone-tag {
    margin-left: 0;
  }

  .page-about .milestone-item:nth-child(odd) .milestone-tag {
    margin-right: 10px;
  }

  .page-about .milestone-item:nth-child(even) .milestone-marker {
    flex-direction: row;
  }

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