.page-about {
  --about-line-w: 26px;
  background: var(--paper);
  color: var(--ink-900);
  font-family: var(--font-body);
}

.page-about .about-hero {
  position: relative;
  overflow: hidden;
  background: var(--ink-950);
  color: var(--white);
  padding: 26px 0 92px;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: -4%;
  right: -4%;
  bottom: -30px;
  height: 66px;
  background: var(--pitch-900);
  transform: skewY(-6deg);
  transform-origin: left bottom;
}

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

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 26px;
  padding: 0;
  list-style: none;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--pitch-200);
}

.page-about .breadcrumb__list a {
  color: var(--pitch-200);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .breadcrumb__list a:hover,
.page-about .breadcrumb__list a:focus-visible {
  color: var(--white);
  border-bottom-color: var(--signal);
}

.page-about .breadcrumb__list li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--ink-800);
}

.page-about .about-hero__eyebrow {
  margin: 0 0 14px;
  color: var(--pitch-200);
}

.page-about .about-hero__title {
  margin: 0 0 20px;
  font-size: clamp(30px, 7.2vw, 58px);
  line-height: 1.08;
  letter-spacing: -0.01em;
  font-weight: 800;
  color: var(--white);
}

.page-about .about-hero__lead {
  max-width: 56ch;
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--pitch-200);
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-facts li {
  border-top: 1px solid var(--ink-800);
  padding-top: 10px;
}

.page-about .about-facts__num {
  display: block;
  font-size: 24px;
  line-height: 1.1;
  color: var(--white);
}

.page-about .about-facts__label {
  display: block;
  margin-top: 6px;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gray-500);
}

/* 时间线长卷 */
.page-about .about-timeline {
  padding: 42px 0 18px;
}

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

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

.page-about .about-chapter {
  position: relative;
  padding: 0 0 54px 42px;
}

.page-about .about-chapter::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 8px;
  bottom: 0;
  width: 1px;
  background: var(--line);
}

.page-about .about-chapter:last-child::before {
  bottom: auto;
  height: 64px;
}

.page-about .about-chapter__num {
  position: absolute;
  left: 0;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: var(--about-line-w);
  height: var(--about-line-w);
  border-radius: 50%;
  background: var(--pitch-900);
  color: var(--white);
  font-size: 11px;
  letter-spacing: 0;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

.page-about .about-chapter:hover .about-chapter__num {
  background: var(--signal);
  color: var(--signal-ink);
  transform: translateY(-2px);
}

.page-about .about-chapter .eyebrow {
  margin: 0 0 10px;
  color: var(--pitch-600);
}

.page-about .about-chapter__title {
  margin: 0 0 18px;
  font-size: clamp(22px, 4.6vw, 32px);
  line-height: 1.22;
  letter-spacing: -0.005em;
  font-weight: 800;
}

.page-about .about-chapter__body p {
  max-width: 64ch;
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
}

.page-about .about-chapter__body p + p {
  margin-top: 16px;
}

.page-about .about-figure {
  margin: 26px 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border: 1px solid var(--line);
  background: var(--paper-2);
}

.page-about .about-figure--square img {
  aspect-ratio: 1 / 1;
}

.page-about .about-figure figcaption {
  margin-top: 10px;
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: 0.03em;
  color: var(--gray-500);
}

.page-about .about-note {
  max-width: 64ch;
  margin: 24px 0 0;
  padding: 16px 18px;
  background: var(--paper-2);
  border-left: 3px solid var(--pitch-900);
  font-size: 15px;
  line-height: 1.72;
  color: var(--ink-900);
}

/* 团队分工 */
.page-about .about-roles {
  display: grid;
  gap: 12px;
  margin: 26px 0 0;
  max-width: 720px;
}

.page-about .about-role {
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: 0 1px 2px rgba(10, 20, 36, 0.04);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .about-role:hover {
  border-color: var(--signal);
  transform: translateY(-2px);
}

.page-about .about-role__summary {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 16px 18px;
  list-style: none;
  cursor: pointer;
}

.page-about .about-role__summary::-webkit-details-marker {
  display: none;
}

.page-about .about-role__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--pitch-600);
}

.page-about .about-role[open] .about-role__summary::after {
  content: "–";
  color: var(--signal);
}

.page-about .about-role__summary:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: -2px;
}

.page-about .about-role__count {
  font-size: 28px;
  line-height: 1;
  color: var(--pitch-900);
}

.page-about .about-role__name {
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--gray-500);
}

.page-about .about-role__body {
  margin: 0 18px 18px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.72;
  color: var(--ink-900);
}

.page-about .about-panel-deep {
  max-width: 720px;
  margin: 20px 0 0;
  padding: 20px;
  background: var(--ink-800);
  color: var(--pitch-200);
  border: 1px solid var(--ink-800);
}

.page-about .about-panel-deep p {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
}

.page-about .about-panel-deep__tag {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px !important;
  font-size: 11px !important;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--white);
}

.page-about .about-panel-deep__tag .num {
  display: inline-block;
  padding: 3px 8px;
  border: 1px solid var(--pitch-600);
  color: var(--signal);
  letter-spacing: 0.04em;
}

/* 收束 */
.page-about .about-cta {
  position: relative;
  background: var(--ink-950);
  color: var(--white);
  padding: 52px 0 60px;
  margin-top: 12px;
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  left: -4%;
  right: -4%;
  top: -26px;
  height: 58px;
  background: var(--pitch-900);
  transform: skewY(-6deg);
  transform-origin: right top;
}

.page-about .about-cta__eyebrow {
  margin: 0 0 14px;
  color: var(--pitch-200);
}

.page-about .about-cta__title {
  margin: 0 0 18px;
  font-size: clamp(24px, 5.2vw, 38px);
  line-height: 1.16;
  font-weight: 800;
  color: var(--white);
}

.page-about .about-cta__lead {
  max-width: 58ch;
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--pitch-200);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 26px 0 0;
}

.page-about .about-cta__ghost {
  color: var(--white);
  border-color: var(--pitch-600);
}

.page-about .about-links {
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink-800);
  max-width: 760px;
}

.page-about .about-links li {
  border-bottom: 1px solid var(--ink-800);
}

.page-about .about-links a {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 0;
  color: var(--white);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.page-about .about-links a:hover .about-links__title,
.page-about .about-links a:focus-visible .about-links__title {
  color: var(--signal);
}

.page-about .about-links a:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 4px;
}

.page-about .about-links__title {
  font-size: 15px;
  letter-spacing: 0.02em;
  transition: color var(--dur) var(--ease);
}

.page-about .about-links__go {
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--gray-500);
}

@media (min-width: 720px) {
  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 22px;
  }

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

  .page-about .about-role__summary {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .page-about .about-role__summary::after {
    margin-left: 0;
  }

  .page-about .about-links a {
    flex-direction: row;
    align-items: baseline;
    justify-content: space-between;
    gap: 20px;
  }
}

@media (min-width: 960px) {
  .page-about .about-hero {
    padding: 34px 0 118px;
  }

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

  .page-about .about-timeline {
    padding: 58px 0 24px;
  }

  .page-about .about-timeline__inner {
    display: grid;
    grid-template-columns: 148px minmax(0, 1fr);
    gap: 56px;
    align-items: start;
  }

  .page-about .about-minirail {
    display: block;
    position: sticky;
    top: 32px;
  }

  .page-about .about-minirail__label {
    margin: 0 0 14px;
    font-size: 11px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--gray-500);
  }

  .page-about .about-minirail__list {
    margin: 0;
    padding: 0;
    list-style: none;
    border-left: 1px solid var(--line);
  }

  .page-about .about-minirail__list a {
    display: flex;
    gap: 10px;
    align-items: baseline;
    margin-left: -1px;
    padding: 8px 0 8px 14px;
    border-left: 2px solid transparent;
    font-size: 13px;
    color: var(--gray-500);
    text-decoration: none;
    transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
  }

  .page-about .about-minirail__list a:hover,
  .page-about .about-minirail__list a:focus-visible {
    color: var(--ink-900);
    border-left-color: var(--pitch-600);
  }

  .page-about .about-minirail__list a:focus-visible {
    outline: 2px solid var(--signal);
    outline-offset: 2px;
  }

  .page-about .about-minirail__list .num {
    font-size: 11px;
    color: var(--pitch-600);
  }

  .page-about .about-chapter {
    padding-bottom: 72px;
  }

  .page-about .about-chapter__title {
    max-width: 20ch;
  }

  .page-about .about-cta {
    padding: 68px 0 76px;
  }
}
</