.page-about {
  --about-cut: 40px;
  position: relative;
  overflow-x: hidden;
}

.page-about .grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2.4vw, 32px);
}

.page-about .col-4 { grid-column: span 4; }
.page-about .col-5 { grid-column: span 5; }
.page-about .col-6 { grid-column: span 6; }
.page-about .col-7 { grid-column: span 7; }
.page-about .col-8 { grid-column: span 8; }

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(18px, 3vw, 32px) 0 clamp(36px, 5vw, 64px);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -180px;
  right: -12%;
  width: min(720px, 96%);
  height: 600px;
  background: radial-gradient(closest-side, rgba(91, 55, 183, 0.42), rgba(58, 34, 112, 0.16) 58%, transparent 78%);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(232, 238, 247, 0.07) 1px, transparent 1px);
  background-size: 26px 26px;
  opacity: 0.55;
  pointer-events: none;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 70%);
}

.page-about .about-hero-shell {
  position: relative;
  z-index: 1;
}

.page-about .about-hero-grid {
  margin-top: clamp(22px, 4vw, 44px);
  align-items: start;
}

.page-about .about-title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(34px, 6.4vw, 74px);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-about .about-hl {
  font-family: var(--font-mono);
  color: var(--lime);
  letter-spacing: -0.01em;
}

.page-about .about-lead {
  margin: 22px 0 0;
  max-width: 46ch;
  font-family: var(--font-body);
  font-size: clamp(15px, 1.3vw, 17px);
  line-height: 1.78;
  color: var(--steel);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.page-about .about-index-card {
  padding: clamp(18px, 2.4vw, 28px);
  border: 1px solid var(--line);
  background: linear-gradient(158deg, rgba(58, 34, 112, 0.34), rgba(13, 18, 32, 0.94) 58%);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%, 0 22px);
}

.page-about .about-side-label {
  margin: 0 0 14px;
  font-family: var(--font-body);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-year-nav {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-year-nav li + li {
  border-top: 1px solid var(--line);
}

.page-about .about-year-nav a {
  display: flex;
  gap: 14px;
  align-items: baseline;
  padding: 13px 4px;
  text-decoration: none;
  color: var(--mist);
  transition: color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .about-year-nav a:hover,
.page-about .about-year-nav a:focus-visible {
  color: var(--cyan);
  background: rgba(34, 227, 255, 0.06);
}

.page-about .about-year-nav-num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--lime);
}

.page-about .about-year-nav-text {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-hero-figure {
  margin: clamp(30px, 5vw, 56px) 0 0;
  border: 1px solid var(--line);
  overflow: hidden;
  clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

/* ---------- 通用章节 ---------- */
.page-about .about-chapter {
  padding: clamp(46px, 7vw, 96px) 0;
}

.page-about .about-chapter--tight {
  padding-top: clamp(24px, 3vw, 40px);
}

.page-about .section-title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.3vw, 40px);
  line-height: 1.16;
  letter-spacing: -0.015em;
  color: var(--mist);
}

.page-about .section-lead {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
  max-width: 42ch;
}

.page-about .about-chapter-body p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.82;
  color: var(--steel);
  max-width: 66ch;
}

.page-about .about-chapter-body p:last-child {
  margin-bottom: 0;
}

.page-about .about-notes {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-notes li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-notes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 8px;
  height: 1px;
  background: var(--cyan);
}

.page-about .about-sub-title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--mist);
}

/* ---------- 流程带 ---------- */
.page-about .about-band {
  padding: clamp(44px, 6vw, 88px) 0;
  background: linear-gradient(180deg, rgba(58, 34, 112, 0.22), rgba(5, 7, 12, 0) 72%);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .about-flow-panel {
  padding: clamp(20px, 3vw, 42px);
  background: var(--panel);
  border: 1px solid var(--line);
  clip-path: polygon(0 0, calc(100% - 34px) 0, 100% 34px, 100% 100%, 0 100%);
}

.page-about .about-flow-head .section-lead {
  max-width: 52ch;
}

.page-about .about-steps {
  list-style: none;
  margin: clamp(24px, 4vw, 40px) 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr;
}

.page-about .about-step {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px 22px;
  border: 1px solid var(--line);
  background: rgba(5, 7, 12, 0.6);
  transition: transform 180ms var(--ease), border-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .about-step:hover,
.page-about .about-step:focus-within {
  transform: translateY(-2px);
  border-color: var(--cyan);
  background: rgba(34, 227, 255, 0.05);
}

.page-about .about-step-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.page-about .about-step-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 0 4px rgba(182, 255, 61, 0.12);
  transition: box-shadow 180ms var(--ease);
}

.page-about .about-step:hover .about-step-dot {
  box-shadow: 0 0 0 6px rgba(182, 255, 61, 0.2);
}

.page-about .about-step-title {
  margin: 4px 0 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .about-step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted);
}

.page-about .about-flow-figure {
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  border: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-flow-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

/* ---------- 团队 ---------- */
.page-about .about-team-grid {
  align-items: start;
}

.page-about .about-team-list {
  margin-top: 26px;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-team-item {
  display: grid;
  grid-template-columns: 66px minmax(0, 1fr);
  gap: 16px;
  padding: 18px 16px;
  background: var(--void);
}

.page-about .about-team-count {
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 2px;
}

.page-about .about-num {
  font-family: var(--font-mono);
  font-size: 30px;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-unit {
  font-size: 12px;
  color: var(--muted);
}

.page-about .about-team-role {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .about-team-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.72;
  color: var(--muted);
}

.page-about .about-team-figure {
  margin: 26px 0 0;
  border: 1px solid var(--line);
  overflow: hidden;
  background: var(--panel);
}

.page-about .about-team-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(0.9);
}

.page-about .about-team-figure figcaption {
  padding: 12px 14px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- 覆盖范围 ---------- */
.page-about .about-coverage-head {
  max-width: 720px;
}

.page-about .about-stats {
  margin-top: clamp(24px, 3.4vw, 40px);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: clamp(16px, 2.4vw, 28px);
  background: var(--void);
}

.page-about .about-stat-num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 42px);
  line-height: 1;
  color: var(--lime);
  letter-spacing: -0.01em;
}

.page-about .about-stat-label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--muted);
}

.page-about .about-coverage-body {
  margin-top: clamp(26px, 3.6vw, 44px);
}

.page-about .about-coverage-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.82;
  color: var(--steel);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline-head {
  max-width: 720px;
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: clamp(30px, 4.4vw, 56px) 0 0;
  padding: 0 0 0 0;
  display: grid;
  gap: clamp(28px, 4vw, 52px);
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 13px;
  top: 6px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, rgba(34, 227, 255, 0.5), var(--line) 40%, var(--line) 88%, rgba(255, 106, 43, 0.45));
}

.page-about .about-tl-item {
  position: relative;
  padding-left: 40px;
  scroll-margin-top: 120px;
}

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: 10px;
  top: 12px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 0 4px rgba(182, 255, 61, 0.14);
}

.page-about .about-tl-year {
  display: block;
  font-family: var(--font-mono);
  font-weight: 100;
  font-size: clamp(40px, 9vw, 64px);
  line-height: 0.9;
  letter-spacing: -0.03em;
  color: rgba(232, 238, 247, 0.16);
}

.page-about .about-tl-body {
  margin-top: 10px;
  padding: 18px 18px 20px;
  border: 1px solid var(--line);
  border-left: 1px solid var(--line);
  background: var(--panel);
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .about-tl-item:hover .about-tl-body {
  border-color: rgba(34, 227, 255, 0.55);
  transform: translateY(-2px);
}

.page-about .about-tl-title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-about .about-tl-body p {
  margin: 0 0 10px;
  font-size: 14px;
  line-height: 1.78;
  color: var(--steel);
}

.page-about .about-tl-tag {
  margin: 0;
}

/* ---------- 规矩 ---------- */
.page-about .about-standards-head {
  max-width: 720px;
}

.page-about .about-rules {
  margin-top: clamp(24px, 3.4vw, 40px);
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
}

.page-about .about-rule {
  padding: 22px 20px 24px;
  border: 1px solid var(--line);
  border-top: 2px solid var(--line);
  background: linear-gradient(180deg, rgba(13, 18, 32, 0.95), rgba(5, 7, 12, 0.95));
  transition: transform 180ms var(--ease), border-color 180ms var(--ease);
}

.page-about .about-rule:nth-child(1) { border-top-color: var(--cyan); }
.page-about .about-rule:nth-child(2) { border-top-color: var(--orange); }
.page-about .about-rule:nth-child(3) { border-top-color: var(--lime); }

.page-about .about-rule:hover {
  transform: translateY(-2px);
  border-color: rgba(34, 227, 255, 0.4);
}

.page-about .about-rule-title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: var(--mist);
}

.page-about .about-rule p {
  margin: 0;
  font-size: 14px;
  line-height: 1.78;
  color: var(--muted);
}

/* ---------- 结尾 ---------- */
.page-about .about-cta-section {
  padding: 0 0 clamp(48px, 7vw, 88px);
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 26px;
  align-items: center;
  justify-content: space-between;
  padding: clamp(24px, 3.6vw, 46px);
  border: 1px solid var(--line);
  background: linear-gradient(118deg, rgba(34, 227, 255, 0.1), rgba(58, 34, 112, 0.38) 58%, rgba(255, 106, 43, 0.12));
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .about-cta-copy {
  flex: 1 1 320px;
  min-width: 0;
}

.page-about .about-cta-title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: clamp(22px, 2.8vw, 32px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.015em;
  color: var(--mist);
}

.page-about .about-cta-copy p {
  margin: 0;
  max-width: 54ch;
  font-size: 14px;
  line-height: 1.78;
  color: var(--steel);
}

.page-about .about-link-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin-top: 16px;
}

.page-about .about-link-row a {
  font-size: 13px;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(34, 227, 255, 0.35);
  padding-bottom: 2px;
  transition: border-color 180ms var(--ease), color 180ms var(--ease);
}

.page-about .about-link-row a:hover,
.page-about .about-link-row a:focus-visible {
  color: var(--mist);
  border-color: var(--mist);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-timeline::before {
    left: 186px;
    top: 34px;
  }

  .page-about .about-tl-item {
    display: grid;
    grid-template-columns: 160px minmax(0, 1fr);
    align-items: start;
    padding-left: 0;
  }

  .page-about .about-tl-item::before {
    left: 182px;
    top: 34px;
  }

  .page-about .about-tl-year {
    text-align: right;
    padding-right: 34px;
    font-size: clamp(52px, 6vw, 88px);
    line-height: 1;
  }

  .page-about .about-tl-body {
    margin-top: 0;
    margin-left: 44px;
    min-height: 132px;
  }

  .page-about .about-tl-item:nth-child(2n) .about-tl-body {
    min-height: 156px;
  }
}

@media (max-width: 899px) {
  .page-about .col-4,
  .page-about .col-5,
  .page-about .col-6,
  .page-about .col-7,
  .page-about .col-8 {
    grid-column: 1 / -1;
  }

  .page-about .about-chapter-head {
    margin-bottom: 26px;
  }

  .page-about .about-team-side {
    order: 2;
  }
}

@media (max-width: 520px) {
  .page-about .about-hero-figure {
    --about-cut: 26px;
  }

  .page-about .about-team-item {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .page-about .about-cta-actions {
    width: 100%;
  }

  .page-about .about-cta-actions .btn {
    flex: 1 1 auto;
    text-align: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-step,
  .page-about .about-tl-body,
  .page-about .about-rule,
  .page-about .about-year-nav a,
  .page-about .about-link-row a {
    transition: none;
  }
}
<<<END>>>