.page-about {
  --ab-grid-max: 1160px;
  --ab-year-size: clamp(68px, 10vw, 148px);
  --ab-gold: #F5C518;
  --ab-gold-soft: rgba(245, 197, 24, 0.14);
  --ab-purple: #9D4EDD;
  --ab-purple-soft: rgba(157, 78, 221, 0.16);
  --ab-orange: #FF6B35;
  --ab-bg-deep: #060914;
  --ab-bg-tier: #0B1026;
  --ab-surface: #1E2A5A;
  --ab-glass: rgba(255, 255, 255, 0.08);
  --ab-glass-border: rgba(255, 255, 255, 0.16);
  --ab-text: #F5F7FA;
  --ab-text-muted: #A0A8B8;
  --ab-radius: 18px;
  --ab-speed: 300ms;
  background: var(--ab-bg-deep);
  color: var(--ab-text);
  font-family: var(--font-body, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif);
  overflow-x: hidden;
}

.page-about img {
  max-width: 100%;
  height: auto;
}

.page-about .container {
  width: min(var(--ab-grid-max), 100% - 48px);
  margin-inline: auto;
}

.page-about .index-label {
  display: inline-block;
  font-family: var(--font-index, "Noto Sans SC", "PingFang SC", sans-serif);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--ab-gold);
  border: 1px solid rgba(245, 197, 24, 0.38);
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(245, 197, 24, 0.08);
  white-space: nowrap;
}

.page-about .data-number {
  font-family: var(--font-number, "Orbitron", "Bahnschrift", "Roboto", sans-serif);
  font-weight: 500;
  line-height: 1;
  letter-spacing: 0.02em;
}

.page-about .glass-card {
  background: linear-gradient(135deg, rgba(255,255,255,0.10), rgba(255,255,255,0.04));
  border: 1px solid var(--ab-glass-border);
  border-radius: var(--ab-radius);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.page-about h1,
.page-about h2,
.page-about h3 {
  font-family: var(--font-display, "Noto Sans SC", "PingFang SC", sans-serif);
  margin: 0;
}

.page-about p {
  margin: 0;
  line-height: 1.7;
}

/* ---------- Hero ---------- */
.page-about .ab-hero {
  padding: 64px 0 80px;
  background: radial-gradient(ellipse at 18% 8%, rgba(157,78,221,0.20), transparent 52%),
              radial-gradient(ellipse at 82% 20%, rgba(245,197,24,0.12), transparent 46%),
              var(--ab-bg-deep);
  border-bottom: 1px solid rgba(255,255,255,0.07);
  position: relative;
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--ab-gold) 0%, var(--ab-purple) 48%, var(--ab-orange) 100%);
  opacity: 0.7;
}

.page-about .ab-hero__topline {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 56px;
}

.page-about .ab-hero__duration {
  font-family: var(--font-number, "Orbitron", sans-serif);
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--ab-text-muted);
  border-left: 2px solid rgba(245,197,24,0.6);
  padding-left: 14px;
}

.page-about .ab-hero__grid {
  display: grid;
  gap: 48px;
  grid-template-columns: 1fr;
}

.page-about .ab-hero__main {
  max-width: 880px;
}

.page-about .ab-hero__kicker {
  font-family: var(--font-index, "Noto Sans SC", sans-serif);
  font-size: 12px;
  letter-spacing: 2px;
  color: var(--ab-text-muted);
  margin-bottom: 20px;
}

.page-about .ab-hero__main h1 {
  font-size: clamp(32px, 5vw, 58px);
  font-weight: 300;
  letter-spacing: 1px;
  line-height: 1.18;
  margin-bottom: 24px;
  color: var(--ab-text);
}

.page-about .ab-hero__lead {
  font-size: 15px;
  color: var(--ab-text-muted);
  max-width: 680px;
}

.page-about .ab-hero__toc {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 24px 0 0 2px;
  border-top: 1px solid rgba(255,255,255,0.10);
}

.page-about .ab-hero__toc-title {
  font-family: var(--font-index, "Noto Sans SC", sans-serif);
  font-size: 11px;
  letter-spacing: 3px;
  color: var(--ab-gold);
  margin-bottom: 14px;
}

.page-about .ab-hero__toc-link {
  display: inline-flex;
  align-items: baseline;
  gap: 14px;
  font-size: 15px;
  color: var(--ab-text);
  text-decoration: none;
  padding: 10px 14px;
  border-radius: 12px;
  transition: background-color var(--ab-speed) ease, color var(--ab-speed) ease;
}

.page-about .ab-hero__toc-link span {
  font-family: var(--font-number, "Orbitron", sans-serif);
  font-size: 12px;
  color: var(--ab-gold);
  letter-spacing: 1px;
}

.page-about .ab-hero__toc-link:hover,
.page-about .ab-hero__toc-link:focus-visible {
  background: rgba(245, 197, 24, 0.10);
  color: var(--ab-gold);
  outline: none;
}

/* ---------- Section head ---------- */
.page-about .ab-section-head {
  margin-bottom: 52px;
  padding-left: 4px;
}

.page-about .ab-section-head h2 {
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 300;
  letter-spacing: 0.5px;
  margin-top: 12px;
}

.page-about .ab-section-head__note {
  margin-top: 12px;
  font-size: 14px;
  color: var(--ab-text-muted);
}

/* ---------- Origin ---------- */
.page-about .ab-origin {
  padding: 96px 0 80px;
  background: var(--ab-bg-deep);
  position: relative;
}

.page-about .ab-origin::before {
  content: "";
  position: absolute;
  top: 40%;
  left: 50%;
  width: 620px;
  height: 620px;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  border: 1px dashed rgba(245, 197, 24, 0.13);
  pointer-events: none;
}

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

.page-about .ab-origin__year {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 8px;
  padding-left: 4px;
}

.page-about .ab-origin__year-num {
  font-size: var(--ab-year-size);
  font-weight: 300;
  color: var(--ab-gold);
  text-shadow: 0 0 60px rgba(245,197,24,0.3);
  line-height: 0.9;
}

.page-about .ab-origin__year-caption {
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--ab-text-muted);
  padding-left: 6px;
  border-left: 2px solid var(--ab-gold);
}

.page-about .ab-origin__story {
  background: linear-gradient(160deg, rgba(255,255,255,0.06), rgba(255,255,255,0.02));
  border: 1px solid rgba(255,255,255,0.10);
  border-radius: var(--ab-radius);
  overflow: hidden;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.page-about .ab-origin__hero {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

.page-about .ab-origin__body {
  padding: 36px;
}

.page-about .ab-origin__text {
  font-size: 15px;
  color: var(--ab-text);
  margin-bottom: 20px;
  max-width: 720px;
}

.page-about .ab-origin__text strong {
  color: var(--ab-gold);
  font-weight: 500;
}

.page-about .ab-origin__facts {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
}

.page-about .ab-origin__facts li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 16px;
  background: rgba(245, 197, 24, 0.05);
  border-left: 3px solid var(--ab-gold);
  border-radius: 0 10px 10px 0;
}

.page-about .ab-origin__fact-num {
  font-family: var(--font-number, "Orbitron", sans-serif);
  font-size: 24px;
  color: var(--ab-gold);
}

.page-about .ab-origin__facts li span:last-child {
  font-size: 14px;
  color: var(--ab-text-muted);
}

/* ---------- Milestones ---------- */
.page-about .ab-milestones {
  padding: 80px 0;
  background: var(--ab-bg-tier);
  position: relative;
}

.page-about .ab-milestones::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  width: 1px;
  height: 100%;
  background: linear-gradient(180deg, transparent, rgba(245,197,24,0.28), rgba(157,78,221,0.24), transparent);
  opacity: 0.4;
}

.page-about .ab-timeline {
  display: grid;
  gap: 36px;
  position: relative;
}

.page-about .ab-milestone {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  position: relative;
}

.page-about .ab-milestone__year {
  display: flex;
  align-items: center;
  gap: 12px;
  padding-left: 4px;
}

.page-about .ab-milestone__year .data-number {
  font-size: clamp(40px, 7vw, 72px);
  font-weight: 300;
  color: var(--ab-text);
  letter-spacing: 0.02em;
  transition: color var(--ab-speed) ease;
}

.page-about .ab-milestone__year:hover .data-number {
  color: var(--ab-gold);
}

.page-about .ab-milestone__star {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ab-gold);
  box-shadow: 0 0 16px rgba(245, 197, 24, 0.8);
  animation: ab-pulse-star 2.6s ease-in-out infinite;
}

.page-about .ab-milestone__card {
  display: grid;
  grid-template-columns: 64px 1fr;
  grid-template-rows: auto auto;
  gap: 14px 16px;
  padding: 24px;
  align-items: start;
}

.page-about .ab-milestone__icon {
  width: 64px;
  height: 64px;
  border-radius: 16px;
  object-fit: cover;
  grid-row: span 2;
}

.page-about .ab-milestone__content h3 {
  font-size: 20px;
  font-weight: 500;
  margin-bottom: 8px;
}

.page-about .ab-milestone__content p {
  font-size: 14px;
  color: var(--ab-text-muted);
}

.page-about .ab-milestone__detail {
  grid-column: 1 / -1;
  margin-top: 4px;
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 12px;
}

.page-about .ab-milestone__detail summary {
  cursor: pointer;
  font-size: 13px;
  color: var(--ab-gold);
  list-style: none;
  padding: 4px 0;
  user-select: none;
  transition: color var(--ab-speed) ease;
}

.page-about .ab-milestone__detail summary::before {
  content: "+";
  display: inline-block;
  margin-right: 8px;
  font-family: var(--font-number, "Orbitron", sans-serif);
  transition: transform var(--ab-speed) ease;
}

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

.page-about .ab-milestone__detail[open] summary::before {
  transform: rotate(45deg);
}

.page-about .ab-milestone__detail ul {
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 6px;
}

.page-about .ab-milestone__detail li {
  font-size: 13px;
  color: var(--ab-text-muted);
  padding-left: 18px;
  position: relative;
}

.page-about .ab-milestone__detail li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--ab-gold);
  opacity: 0.7;
}

/* ---------- Data System ---------- */
.page-about .ab-data-system {
  padding: 80px 0;
  background: var(--ab-bg-deep);
  position: relative;
  overflow: hidden;
}

.page-about .ab-data-system::before {
  content: "";
  position: absolute;
  top: 0;
  right: -10%;
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(157,78,221,0.14), transparent 62%);
  pointer-events: none;
  border-radius: 50%;
}

.page-about .ab-data-system__intro {
  max-width: 720px;
  margin-bottom: 44px;
  padding-left: 4px;
}

.page-about .ab-data-system__intro p {
  font-size: 15px;
  color: var(--ab-text-muted);
}

.page-about .ab-flow {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .ab-flow__step {
  padding: 26px;
  position: relative;
  overflow: hidden;
}

.page-about .ab-flow__step::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--ab-gold), var(--ab-purple), var(--ab-orange));
  opacity: 0.6;
}

.page-about .ab-flow__no {
  font-family: var(--font-number, "Orbitron", sans-serif);
  font-size: 14px;
  color: var(--ab-gold);
  letter-spacing: 2px;
  display: block;
  margin-bottom: 12px;
}

.page-about .ab-flow__step h3 {
  font-size: 20px;
  font-weight: 500;
  margin-bottom: 10px;
}

.page-about .ab-flow__step p {
  font-size: 14px;
  color: var(--ab-text-muted);
  margin-bottom: 14px;
}

.page-about .ab-flow__meta {
  display: inline-block;
  font-size: 12px;
  color: var(--ab-purple);
  background: var(--ab-purple-soft);
  border-radius: 999px;
  padding: 6px 14px;
  border: 1px solid rgba(157, 78, 221, 0.28);
  font-family: var(--font-index, "Noto Sans SC", sans-serif);
  letter-spacing: 1px;
}

.page-about .ab-data-system__assurance {
  margin-top: 48px;
  padding: 32px;
  border-radius: var(--ab-radius);
  background: linear-gradient(120deg, rgba(245,197,24,0.10), rgba(157,78,221,0.08));
  border: 1px solid rgba(245,197,24,0.22);
}

.page-about .ab-data-system__assurance .index-label {
  margin-bottom: 14px;
}

.page-about .ab-data-system__assurance p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ab-text);
  margin-top: 12px;
  max-width: 760px;
}

/* ---------- Team ---------- */
.page-about .ab-team {
  padding: 80px 0 96px;
  background: var(--ab-bg-tier);
  position: relative;
}

.page-about .ab-team__layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 44px;
}

.page-about .ab-team__lead {
  font-size: 15px;
  color: var(--ab-text-muted);
  margin-bottom: 28px;
  max-width: 680px;
}

.page-about .ab-team__filter {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 28px;
}

.page-about .ab-team__filter-btn {
  appearance: none;
  border: 1px solid rgba(255,255,255,0.16);
  background: rgba(255,255,255,0.05);
  color: var(--ab-text-muted);
  font-size: 13px;
  font-family: var(--font-body, "Noto Sans SC", sans-serif);
  padding: 9px 18px;
  border-radius: 999px;
  cursor: pointer;
  transition: background-color var(--ab-speed) ease, color var(--ab-speed) ease, border-color var(--ab-speed) ease;
}

.page-about .ab-team__filter-btn:hover,
.page-about .ab-team__filter-btn:focus-visible {
  border-color: var(--ab-gold);
  color: var(--ab-gold);
  outline: none;
}

.page-about .ab-team__filter-btn[aria-pressed="true"] {
  background: var(--ab-gold-soft);
  border-color: var(--ab-gold);
  color: var(--ab-gold);
}

.page-about .ab-team__cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.page-about .ab-team__card {
  padding: 28px;
  transition: opacity var(--ab-speed) ease, transform var(--ab-speed) ease;
}

.page-about .ab-team__card[hidden] {
  display: none;
}

.page-about .ab-team__card-role {
  display: inline-block;
  font-size: 11px;
  letter-spacing: 3px;
  font-family: var(--font-index, "Noto Sans SC", sans-serif);
  color: var(--ab-purple);
  border: 1px solid rgba(157,78,221,0.38);
  border-radius: 999px;
  padding: 6px 12px;
  margin-bottom: 14px;
  background: var(--ab-purple-soft);
}

.page-about .ab-team__card h3 {
  font-size: 22px;
  font-weight: 500;
  margin-bottom: 10px;
}

.page-about .ab-team__card p {
  font-size: 14px;
  color: var(--ab-text-muted);
  margin-bottom: 14px;
}

.page-about .ab-team__card-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--ab-gold);
  background: var(--ab-gold-soft);
  border-radius: 6px;
  padding: 5px 10px;
}

.page-about .ab-team__visual {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.page-about .ab-team__visual img {
  width: 100%;
  border-radius: var(--ab-radius);
  border: 1px solid rgba(255,255,255,0.10);
}

.page-about .ab-team__visual-caption {
  font-size: 13px;
  color: var(--ab-text-muted);
  letter-spacing: 0.5px;
  line-height: 1.6;
  padding-left: 12px;
  border-left: 2px solid var(--ab-gold);
}

/* ---------- Service & Links ---------- */
.page-about .ab-service {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  margin-top: 64px;
  padding-top: 48px;
  border-top: 1px solid rgba(255,255,255,0.08);
}

.page-about .ab-service__card {
  background: linear-gradient(135deg, rgba(255,255,255,0.07), rgba(255,255,255,0.02));
  border: 1px solid rgba(255,255,255,0.10);
  border-radius: var(--ab-radius);
  padding: 32px;
}

.page-about .ab-service__card h3 {
  font-size: 22px;
  font-weight: 500;
  margin: 14px 0 12px;
}

.page-about .ab-service__card p {
  font-size: 14px;
  color: var(--ab-text-muted);
  max-width: 640px;
}

.page-about .ab-service__links {
  display: grid;
  gap: 8px;
  align-content: start;
}

.page-about .ab-service__links .index-label {
  margin-bottom: 14px;
}

.page-about .ab-service__link {
  display: block;
  font-size: 15px;
  color: var(--ab-text);
  text-decoration: none;
  padding: 14px 16px;
  border-radius: 12px;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
  transition: background-color var(--ab-speed) ease, color var(--ab-speed) ease, border-color var(--ab-speed) ease, transform var(--ab-speed) ease;
}

.page-about .ab-service__link:hover,
.page-about .ab-service__link:focus-visible {
  background: var(--ab-gold-soft);
  border-color: var(--ab-gold);
  color: var(--ab-gold);
  transform: translateX(4px);
  outline: none;
}

/* ---------- Reveal ---------- */
.page-about [data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s var(--ease-out, cubic-bezier(0.22, 1, 0.36, 1)), transform 0.6s var(--ease-out, cubic-bezier(0.22, 1, 0.36, 1));
}

.page-about [data-reveal].is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  .page-about [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .page-about .ab-milestone__star {
    animation: none;
  }
}

@keyframes ab-pulse-star {
  0%, 100% { box-shadow: 0 0 12px rgba(245, 197, 24, 0.6); opacity: 0.9; }
  50% { box-shadow: 0 0 28px rgba(245, 197, 24, 1); opacity: 1; }
}

/* ---------- Desktop media query ---------- */
@media (min-width: 800px) {
  .page-about .ab-hero {
    padding: 80px 0 96px;
  }

  .page-about .ab-hero__grid {
    grid-template-columns: 2.2fr 1fr;
    gap: 64px;
    align-items: end;
  }

  .page-about .ab-hero__toc {
    padding-top: 0;
    border-top: 0;
    border-left: 1px solid rgba(255,255,255,0.10);
    padding-left: 28px;
    gap: 2px;
  }

  .page-about .ab-origin {
    padding: 120px 0 96px;
  }

  .page-about .ab-origin__layout {
    grid-template-columns: 0.88fr 1.62fr;
    gap: 48px;
    align-items: start;
  }

  .page-about .ab-origin__year {
    position: sticky;
    top: 90px;
  }

  .page-about .ab-origin__facts {
    grid-template-columns: 1fr 1fr 1fr;
    gap: 12px;
  }

  .page-about .ab-origin__facts li {
    flex-direction: column;
    gap: 4px;
    padding: 14px 16px;
  }

  .page-about .ab-timeline {
    gap: 44px;
  }

  .page-about .ab-milestone {
    grid-template-columns: 180px 1fr;
    gap: 24px;
    align-items: start;
  }

  .page-about .ab-milestone__year {
    justify-content: flex-end;
    padding-right: 20px;
    border-right: 2px solid rgba(245,197,24,0.35);
    position: relative;
    align-self: stretch;
  }

  .page-about .ab-milestone__year .data-number {
    font-size: 72px;
  }

  .page-about .ab-milestone__star {
    position: absolute;
    right: -7px;
    top: 18px;
  }

  .page-about .ab-milestone__card {
    grid-template-columns: 88px 1fr;
    grid-template-rows: auto auto;
    padding: 30px;
    gap: 10px 24px;
  }

  .page-about .ab-milestone__icon {
    width: 88px;
    height: 88px;
    border-radius: 20px;
  }

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

  .page-about .ab-data-system {
    padding: 96px 0;
  }

  .page-about .ab-team {
    padding: 96px 0 110px;
  }

  .page-about .ab-team__layout {
    grid-template-columns: 1.25fr 0.75fr;
    gap: 56px;
    align-items: start;
  }

  .page-about .ab-team__visual {
    position: sticky;
    top: 96px;
  }

  .page-about .ab-team__visual img {
    height: auto;
    object-fit: cover;
  }

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

  .page-about .ab-service {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    align-items: center;
  }
}

@media (min-width: 1120px) {
  .page-about .ab-flow {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .ab-milestone {
    grid-template-columns: 220px 1fr;
  }

  .page-about .ab-milestone__year .data-number {
    font-size: 84px;
  }
}