.page-about {
  --about-rail-w: 54px;
  --about-shadow: 0 1px 0 rgba(14, 16, 21, .04), 0 10px 26px -22px rgba(14, 16, 21, .5);
  --node-color: var(--ab-red);
  background: var(--ab-paper);
  overflow-x: hidden;
}

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

/* ---------- 首屏：框景 ---------- */

.page-about .about-hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  padding: 26px 18px 28px;
  background: #fff;
  border: var(--ab-hair) solid var(--ab-line);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--ab-red) 0 50%, var(--ab-blue) 50% 100%);
}

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

.page-about .about-hero__eyebrow {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 14px;
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--ab-font-sans);
  font-weight: 900;
  font-size: clamp(2.1rem, 8.4vw, 3.9rem);
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--ab-ink);
}

.page-about .about-hero__hl {
  display: inline-block;
  color: var(--ab-red);
}

.page-about .about-hero__desc {
  margin: 18px 0 0;
  max-width: 46ch;
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--ab-ink-70);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
}

.page-about .about-hero__board {
  padding: 20px 18px;
  background:
    linear-gradient(158deg, rgba(18, 87, 214, .30) 0%, rgba(11, 18, 48, 0) 58%),
    var(--ab-indigo);
  color: var(--ab-paper);
}

.page-about .about-hero__board-title {
  margin: 0 0 6px;
  font-size: .75rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ab-paper-65);
}

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

.page-about .about-figs__item {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 12px 0;
  border-bottom: var(--ab-hair) solid var(--ab-paper-18);
}

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

.page-about .about-figs__num {
  flex: 0 0 auto;
  min-width: 3.6ch;
  font-family: var(--ab-font-mono);
  font-weight: 700;
  font-size: 1.6875rem;
  letter-spacing: -.02em;
  color: var(--ab-amber);
}

.page-about .about-figs__label {
  font-size: .9375rem;
  line-height: 1.5;
  color: var(--ab-paper-85);
}

/* ---------- 侧边说明卡 ---------- */

.page-about .about-sidecard {
  margin-top: 24px;
  padding: 20px 18px;
  background: var(--ab-green);
  color: var(--ab-paper);
}

.page-about .about-sidecard__title {
  margin: 0 0 12px;
  font-size: .75rem;
  letter-spacing: .12em;
  color: var(--ab-paper-65);
}

.page-about .about-sidecard__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.page-about .about-sidecard__list li {
  position: relative;
  padding-left: 16px;
  font-size: .9375rem;
  line-height: 1.6;
  color: var(--ab-paper-85);
}

.page-about .about-sidecard__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 6px;
  height: 6px;
  background: var(--ab-amber);
  border-radius: 50%;
}

/* ---------- 档案库 ---------- */

.page-about .about-archive__figure {
  margin: 0 0 24px;
  border: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-archive {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-archive__card {
  --card-accent: var(--ab-red);
  position: relative;
  padding: 22px 18px 22px 22px;
  background: #fff;
  border: var(--ab-hair) solid var(--ab-line);
  box-shadow: var(--about-shadow);
  transition: transform var(--ab-dur) var(--ab-ease),
              border-color var(--ab-dur) var(--ab-ease);
}

.page-about .about-archive__card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 100%;
  background: var(--card-accent);
}

.page-about .about-archive__card:nth-child(2) { --card-accent: var(--ab-blue); }
.page-about .about-archive__card:nth-child(3) { --card-accent: var(--ab-violet); }
.page-about .about-archive__card:nth-child(4) { --card-accent: var(--ab-wine); }

.page-about .about-archive__card:hover {
  transform: translateY(-2px);
  border-color: var(--card-accent);
}

.page-about .about-archive__no {
  margin: 0;
  font-family: var(--ab-font-mono);
  font-size: .75rem;
  letter-spacing: .12em;
  color: var(--card-accent);
}

.page-about .about-archive__title {
  margin: 10px 0 8px;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--ab-ink);
}

.page-about .about-archive__desc {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.7;
  color: var(--ab-ink-70);
}

.page-about .about-archive__stat {
  display: block;
  margin-top: 16px;
  padding-top: 12px;
  border-top: var(--ab-hair) solid var(--ab-line);
  font-family: var(--ab-font-mono);
  font-size: 1.375rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ab-ink);
}

.page-about .about-archive__stat small {
  display: block;
  margin-top: 4px;
  font-family: var(--ab-font-sans);
  font-size: .75rem;
  font-weight: 400;
  letter-spacing: .04em;
  color: var(--ab-ink-50);
}

/* ---------- 团队分工带 ---------- */

.page-about .about-team__tabs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  background: #fff;
  border: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-team__tab {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
  padding: 16px 14px;
  border: 0;
  border-bottom: var(--ab-hair) solid var(--ab-line);
  border-right: var(--ab-hair) solid var(--ab-line);
  background: transparent;
  color: var(--ab-ink);
  font-family: var(--ab-font-sans);
  text-align: left;
  cursor: pointer;
  transition: background var(--ab-dur) var(--ab-ease),
              color var(--ab-dur) var(--ab-ease);
}

.page-about .about-team__tab:nth-child(2n) {
  border-right: 0;
}

.page-about .about-team__tab:hover,
.page-about .about-team__tab:focus-visible,
.page-about .about-team__tab[aria-selected="true"] {
  background: var(--ab-indigo);
  color: var(--ab-paper);
}

.page-about .about-team__no {
  font-family: var(--ab-font-mono);
  font-size: .75rem;
  letter-spacing: .12em;
  color: var(--ab-blue);
}

.page-about .about-team__tab:hover .about-team__no,
.page-about .about-team__tab:focus-visible .about-team__no,
.page-about .about-team__tab[aria-selected="true"] .about-team__no {
  color: var(--ab-amber);
}

.page-about .about-team__name {
  font-size: 1.0625rem;
  font-weight: 700;
  letter-spacing: -.01em;
}

.page-about .about-team__panels {
  display: grid;
  gap: 0;
  margin-top: 22px;
}

.page-about .about-team__panel {
  padding: 0 0 20px;
  margin-bottom: 20px;
  border-bottom: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-team__panel:last-child {
  border-bottom: 0;
  margin-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-team__panel h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ab-ink);
}

.page-about .about-team__panel p {
  margin: 0;
  max-width: 70ch;
  font-size: .9375rem;
  line-height: 1.78;
  color: var(--ab-ink-70);
}

/* ---------- 从线索到成稿 ---------- */

.page-about .about-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 28px;
}

.page-about .about-flow__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-flow__step {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 14px;
  padding: 18px 12px 18px 14px;
  border-bottom: var(--ab-hair) solid var(--ab-line);
  border-left: 3px solid transparent;
  transition: background var(--ab-dur) var(--ab-ease),
              border-left-color var(--ab-dur) var(--ab-ease);
}

.page-about .about-flow__step:hover,
.page-about .about-flow__step:focus-within {
  background: #fff;
  border-left-color: var(--ab-red);
}

.page-about .about-flow__no {
  font-family: var(--ab-font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1;
  padding-top: 4px;
  color: var(--ab-blue);
}

.page-about .about-flow__title {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ab-ink);
}

.page-about .about-flow__desc {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.72;
  color: var(--ab-ink-70);
}

.page-about .about-flow__figure {
  margin: 0;
  border: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-flow__note {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 26px 0 0;
  padding: 16px 18px;
  background: var(--ab-green);
  color: var(--ab-paper-85);
  font-size: .9375rem;
  line-height: 1.7;
}

.page-about .about-flow__note .ab-dot {
  flex: 0 0 auto;
  margin-top: .55em;
}

/* ---------- 合作与转载 ---------- */

.page-about .about-partners {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-partners__card {
  --card-accent: var(--ab-red);
  padding: 22px 20px;
  background: #fff;
  border: var(--ab-hair) solid var(--ab-line);
  border-top: 3px solid var(--card-accent);
  box-shadow: var(--about-shadow);
  transition: transform var(--ab-dur) var(--ab-ease);
}

.page-about .about-partners__card--blue { --card-accent: var(--ab-blue); }
.page-about .about-partners__card--violet { --card-accent: var(--ab-violet); }

.page-about .about-partners__card:hover {
  transform: translateY(-2px);
}

.page-about .about-partners__card h3 {
  margin: 0 0 10px;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ab-ink);
}

.page-about .about-partners__card p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.75;
  color: var(--ab-ink-70);
}

.page-about .about-partners__card .ab-btn {
  margin-top: 16px;
}

/* ---------- 发展历程时间轴 ---------- */

.page-about .about-timeline__figure {
  margin: 0 0 30px;
  border: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0 0 0 30px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg,
    var(--ab-red) 0%,
    var(--ab-blue) 48%,
    var(--ab-violet) 100%);
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 30px;
  outline: none;
}

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

.page-about .about-timeline__item:nth-child(1) { --node-color: var(--ab-red); }
.page-about .about-timeline__item:nth-child(2) { --node-color: var(--ab-blue); }
.page-about .about-timeline__item:nth-child(3) { --node-color: var(--ab-violet); }
.page-about .about-timeline__item:nth-child(4) { --node-color: var(--ab-wine); }
.page-about .about-timeline__item:nth-child(5) { --node-color: var(--ab-green); }

.page-about .about-timeline__node {
  position: absolute;
  left: -28px;
  top: 5px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--ab-paper);
  border: 2px solid var(--node-color);
  transition: transform var(--ab-dur) var(--ab-ease),
              background var(--ab-dur) var(--ab-ease);
}

.page-about .about-timeline__item:hover .about-timeline__node,
.page-about .about-timeline__item:focus-visible .about-timeline__node {
  transform: scale(1.15);
  background: var(--node-color);
}

.page-about .about-timeline__item:focus-visible {
  outline: 2px solid var(--ab-amber);
  outline-offset: 4px;
}

.page-about .about-timeline__year {
  margin: 0 0 6px;
  font-family: var(--ab-font-mono);
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .1em;
  color: var(--node-color);
}

.page-about .about-timeline__title {
  margin: 0 0 6px;
  font-size: 1.0625rem;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ab-ink);
}

.page-about .about-timeline__desc {
  margin: 0;
  max-width: 64ch;
  font-size: .9375rem;
  line-height: 1.75;
  color: var(--ab-ink-70);
}

/* ---------- 结尾入口 ---------- */

.page-about .about-cta {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
  padding: 30px 22px;
  background:
    linear-gradient(118deg,
      rgba(224, 31, 45, .92) 0%,
      rgba(122, 23, 48, .94) 46%,
      var(--ab-indigo) 100%);
  color: var(--ab-paper);
  border: var(--ab-hair) solid var(--ab-line);
}

.page-about .about-cta__title {
  margin: 0;
  font-size: clamp(1.375rem, 4.4vw, 2.0625rem);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -.01em;
}

.page-about .about-cta__desc {
  margin: 14px 0 0;
  max-width: 52ch;
  font-size: .9375rem;
  line-height: 1.78;
  color: var(--ab-paper-85);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-content: flex-start;
}

/* ---------- 小屏微调 ---------- */

@media (max-width: 379px) {
  .page-about .about-team__tabs {
    grid-template-columns: minmax(0, 1fr);
  }

  .page-about .about-team__tab {
    border-right: 0;
  }
}

/* ---------- 中等屏幕 ---------- */

@media (min-width: 720px) {
  .page-about .about-archive {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-about .about-partners__card:last-child {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 26px;
  }

  .page-about .about-partners__card:last-child .ab-btn {
    margin-top: 0;
    flex: 0 0 auto;
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, .8fr);
    align-items: center;
    padding: 36px 30px;
  }

  .page-about .about-cta__actions {
    justify-content: flex-end;
  }
}

/* ---------- 桌面 ---------- */

@media (min-width: 860px) {
  .page-about .about-team__tabs {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-team__tab,
  .page-about .about-team__tab:nth-child(2n) {
    border-right: var(--ab-hair) solid var(--ab-line);
    border-bottom: 0;
    padding: 20px 16px 22px;
  }

  .page-about .about-team__tab:last-child {
    border-right: 0;
  }

  .page-about .about-team__panels {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: 32px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    grid-template-columns: var(--about-rail-w) minmax(0, 1.15fr) minmax(0, .85fr);
    gap: 30px;
    padding: 38px 34px 40px;
  }

  .page-about .about-hero__rail {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 24px;
    padding-right: 16px;
    border-right: var(--ab-hair) solid var(--ab-line);
  }

  .page-about .about-hero__desc {
    font-size: 1.125rem;
  }

  .page-about .about-hero__board {
    align-self: stretch;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 26px 22px;
  }

  .page-about .about-flow {
    grid-template-columns: minmax(0, 1.28fr) minmax(0, .72fr);
    align-items: start;
    gap: 44px;
  }

  .page-about .about-sidecard {
    margin-top: 0;
  }
}

@media (min-width: 1080px) {
  .page-about .about-archive {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-timeline {
    padding-left: 36px;
  }

  .page-about .about-timeline__node {
    left: -34px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-archive__card,
  .page-about .about-partners__card,
  .page-about .about-flow__step,
  .page-about .about-timeline__node,
  .page-about .about-team__tab {
    transition: none;
  }

  .page-about .about-archive__card:hover,
  .page-about .about-partners__card:hover,
  .page-about .about-timeline__item:hover .about-timeline__node,
  .page-about .about-timeline__item:focus-visible .about-timeline__node {
    transform: none;
  }
}