.page-about {
  background: var(--ink);
  color: var(--paper);
  padding-bottom: var(--space-5);
  overflow-x: hidden;
}

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

.page-about p {
  margin: 0;
  line-height: 1.55;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: var(--space-4) 0 var(--space-5);
  border-bottom: var(--edge);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -18%;
  right: -55%;
  width: 130%;
  height: 150%;
  background: var(--ink-2);
  border-left: var(--edge);
  transform: rotate(-7deg);
  transform-origin: top right;
  z-index: 0;
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--space-4);
}

.page-about .about-hero .breadcrumb {
  grid-column: 1 / -1;
}

.page-about .about-hero__copy {
  display: grid;
  gap: var(--space-3);
  align-content: start;
}

.page-about .about-hero__copy h1 {
  margin: 0;
  font-size: clamp(32px, 7vw, 76px);
  line-height: 1.02;
  letter-spacing: -0.02em;
  font-weight: 800;
}

.page-about .about-hero__lede {
  max-width: 46ch;
  font-size: 15px;
  color: var(--paper);
  opacity: 0.86;
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-hero__plate {
  background: var(--ink-2);
  border: var(--edge-strong);
  box-shadow: var(--shadow-hard);
  padding: var(--space-3);
  align-self: start;
}

.page-about .about-stats {
  list-style: none;
  margin: var(--space-2) 0 0;
  padding: 0;
  display: grid;
}

.page-about .about-stats li {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  align-items: baseline;
  gap: var(--space-2);
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-stats li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-stats__num {
  font-size: 26px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-stats__cap {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.4;
}

/* ---------- 刻度导航 + 内容流 ---------- */
.page-about .about-track {
  padding-top: var(--space-4);
}

.page-about .about-rail {
  margin-bottom: var(--space-3);
}

.page-about .about-rail__list {
  display: flex;
  gap: 0;
  list-style: none;
  margin: 0;
  padding: 0 0 4px;
  overflow-x: auto;
  border-bottom: var(--edge);
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

.page-about .about-rail__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 12px;
  font-size: 13px;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .about-rail__link .mono {
  font-size: 11px;
  color: var(--line);
}

.page-about .about-rail__link:hover {
  color: var(--paper);
}

.page-about .about-rail__link.is-active {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .about-rail__link.is-active .mono {
  color: var(--cyan);
}

/* ---------- 章节通用 ---------- */
.page-about .about-sec {
  padding: var(--space-4) 0;
  border-top: var(--edge);
}

.page-about .about-flow > .about-sec:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-sec__head h2 {
  margin: 8px 0 0;
  font-size: clamp(22px, 4.2vw, 38px);
  line-height: 1.12;
  letter-spacing: -0.01em;
  font-weight: 800;
}

.page-about .about-sec__body {
  margin-top: var(--space-3);
  max-width: 62ch;
  font-size: 15px;
  color: var(--paper);
  opacity: 0.88;
}

.page-about .about-sec__body p + p {
  margin-top: 12px;
}

.page-about .about-sec .media-frame {
  margin-top: var(--space-3);
}

/* ---------- 三步路径 ---------- */
.page-about .about-path {
  list-style: none;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .about-path li {
  display: grid;
  gap: 4px;
  padding: var(--space-2) var(--space-3);
  background: var(--ink-2);
  border: var(--edge);
  border-left: 4px solid var(--cyan-dim);
}

.page-about .about-path__step {
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .about-path strong {
  font-size: 16px;
  font-weight: 700;
}

.page-about .about-path span:last-child {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.45;
}

/* ---------- 团队 ---------- */
.page-about .about-team__grid {
  display: grid;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.page-about .about-team__card {
  background: var(--ink-2);
  border: var(--edge);
  padding: var(--space-3);
}

.page-about .about-team__card .mono {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--orange);
}

.page-about .about-team__card h3 {
  margin: 8px 0 8px;
  font-size: 18px;
  font-weight: 700;
}

.page-about .about-team__card p {
  font-size: 13.5px;
  color: var(--muted);
}

.page-about .about-handoff {
  margin-top: var(--space-4);
  padding-top: var(--space-3);
  border-top: var(--edge);
}

.page-about .about-handoff__title {
  margin: 0 0 var(--space-2);
  font-size: 18px;
  font-weight: 700;
}

.page-about .about-handoff__list {
  list-style: none;
  margin: var(--space-2) 0 0;
  padding: 0;
  display: grid;
  gap: 8px;
}

.page-about .about-handoff__item {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: var(--space-2);
  align-items: start;
  padding: 12px 14px;
  background: var(--ink-2);
  border-left: 3px solid var(--line);
  font-size: 13.5px;
  line-height: 1.5;
  transition: border-color var(--dur) var(--ease);
}

.page-about .about-handoff__item:hover {
  border-left-color: var(--cyan);
}

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

.page-about .about-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--cyan);
  white-space: nowrap;
}

/* ---------- 四段流程 ---------- */
.page-about .about-flow4 {
  list-style: none;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: var(--space-2);
}

.page-about .about-flow4 li {
  position: relative;
  background: var(--ink-2);
  border: var(--edge);
  padding: var(--space-3);
}

.page-about .about-flow4__num {
  font-size: 24px;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-flow4 h3 {
  margin: 10px 0 8px;
  font-size: 17px;
  font-weight: 700;
}

.page-about .about-flow4 p {
  font-size: 13.5px;
  color: var(--muted);
}

.page-about .about-flow4__out {
  display: inline-block;
  margin-top: 12px;
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--ink);
  background: var(--cyan);
}

/* ---------- 时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  margin-top: var(--space-3);
  padding: var(--space-3);
  border: var(--edge);
  background: var(--ink-2);
  overflow: hidden;
}

.page-about .about-timeline__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.16;
  filter: grayscale(0.35);
  z-index: 0;
  pointer-events: none;
}

.page-about .about-timeline__list {
  position: relative;
  z-index: 1;
  list-style: none;
  margin: 0;
  padding: 0 0 0 22px;
  border-left: 2px dashed var(--line);
  display: grid;
  gap: var(--space-3);
}

.page-about .about-timeline__list li {
  position: relative;
}

.page-about .about-timeline__list li::before {
  content: "";
  position: absolute;
  left: -29px;
  top: 7px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px var(--ink-2);
}

.page-about .about-timeline__year {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .about-timeline__year::before {
  content: "";
  display: inline-block;
  width: 18px;
  height: 3px;
  background: var(--orange);
}

.page-about .about-timeline__list h3 {
  margin: 8px 0 6px;
  font-size: 16px;
  font-weight: 700;
}

.page-about .about-timeline__list p {
  font-size: 13.5px;
  color: var(--muted);
}

/* ---------- 质量把关 ---------- */
.page-about .about-quality {
  display: grid;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.page-about .about-quality__item {
  background: var(--ink-2);
  border: var(--edge);
  border-top: 4px solid var(--cyan);
  padding: var(--space-3);
}

.page-about .about-quality__num {
  font-size: 26px;
  line-height: 1;
  color: var(--orange);
}

.page-about .about-quality__item h3 {
  margin: 10px 0 8px;
  font-size: 17px;
  font-weight: 700;
}

.page-about .about-quality__item p {
  font-size: 13.5px;
  color: var(--muted);
}

/* ---------- 合作 ---------- */
.page-about .about-partners {
  list-style: none;
  margin: var(--space-3) 0 0;
  padding: 0;
  display: grid;
  gap: var(--space-2);
}

.page-about .about-partners li {
  background: var(--paper);
  color: var(--ink);
  padding: var(--space-3);
  box-shadow: var(--shadow-soft);
}

.page-about .about-partners__idx {
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--ink);
  opacity: 0.55;
}

.page-about .about-partners h3 {
  margin: 8px 0 8px;
  font-size: 17px;
  font-weight: 800;
}

.page-about .about-partners p {
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--ink);
  opacity: 0.76;
}

/* ---------- 入口 ---------- */
.page-about .about-sec--join {
  border-top: var(--edge-strong);
  max-width: 62ch;
}

.page-about .about-sec--join h2 {
  margin: 0;
  font-size: clamp(22px, 4.2vw, 34px);
  line-height: 1.14;
  font-weight: 800;
}

.page-about .about-join__lede {
  margin-top: var(--space-2);
  font-size: 15px;
  color: var(--paper);
  opacity: 0.86;
}

.page-about .about-join__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: var(--space-3);
}

.page-about .about-join__note {
  margin-top: var(--space-2);
  font-size: 13px;
  color: var(--muted);
}

.page-about .about-join__note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid currentColor;
}

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

/* ---------- 响应式 ---------- */
@media (min-width: 720px) {
  .page-about .about-hero__inner {
    gap: var(--space-5);
  }

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

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

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

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

@media (min-width: 900px) {
  .page-about .about-flow4 {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: var(--space-3);
  }

  .page-about .about-flow4 li:not(:last-child)::after {
    content: "→";
    position: absolute;
    top: var(--space-3);
    right: calc(-1 * var(--space-3));
    width: var(--space-3);
    text-align: center;
    font-size: 18px;
    line-height: 1;
    color: var(--orange);
  }

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

@media (min-width: 1024px) {
  .page-about .about-hero {
    padding-top: var(--space-5);
  }

  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    align-items: start;
  }

  .page-about .about-hero::before {
    right: -32%;
    width: 78%;
  }

  .page-about .about-track {
    display: grid;
    grid-template-columns: 168px minmax(0, 1fr);
    gap: var(--space-4);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: 96px;
    margin-bottom: 0;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    overflow: visible;
    border-bottom: 0;
    border-left: var(--edge);
    padding: 0;
  }

  .page-about .about-rail__link {
    justify-content: flex-start;
    width: 100%;
    padding: 10px 12px;
    margin-left: -2px;
    border-bottom: 0;
    border-left: 2px solid transparent;
  }

  .page-about .about-rail__link.is-active {
    border-left-color: var(--cyan);
  }

  .page-about .about-team__grid {
    grid-template-columns: 1.15fr 1fr 1fr 1.15fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-rail__link,
  .page-about .about-handoff__item {
    transition: none;
  }
}