.page-about {
  --qa-axis-w: 124px;
  --qa-rail-x: 12px;
}

/* ——— 面包屑 ——— */
.page-about .qa-crumb {
  padding-top: 20px;
}

/* ——— 首屏 ——— */
.page-about .qa-hero {
  position: relative;
  padding: 32px 0 56px;
  border-bottom: 1px solid var(--grid-line);
  overflow: hidden;
}

.page-about .qa-hero__mesh {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(34, 55, 94, 0.55) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(34, 55, 94, 0.55) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: radial-gradient(130% 100% at 12% 0%, #000 0%, transparent 72%);
  mask-image: radial-gradient(130% 100% at 12% 0%, #000 0%, transparent 72%);
}

.page-about .qa-hero__inner {
  position: relative;
  display: grid;
  gap: 40px;
  align-items: center;
}

.page-about .qa-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-narrow);
  font-weight: 700;
  font-size: clamp(30px, 5.6vw, 58px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--cold-white);
}

.page-about .qa-hero__lede {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.7;
  color: var(--slate);
}

.page-about .qa-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .qa-hero__visual {
  position: relative;
  width: 100%;
  max-width: 400px;
  margin: 0 auto;
  aspect-ratio: 1 / 1;
}

.page-about .qa-dial {
  display: block;
  width: 100%;
  height: 100%;
}

.page-about .qa-hero__readout {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  pointer-events: none;
}

.page-about .qa-hero__readout-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(38px, 8vw, 62px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--cyan);
}

.page-about .qa-hero__readout-cap {
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--slate);
}

/* ——— 主体栅格 ——— */
.page-about .qa-body {
  padding: 48px 0 88px;
}

.page-about .qa-body__grid {
  display: grid;
  gap: 28px;
}

/* ——— 左侧刻度轴 ——— */
.page-about .qa-axis {
  position: relative;
}

.page-about .qa-axis__rail {
  display: none;
}

.page-about .qa-axis__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 8px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .qa-axis__list::-webkit-scrollbar {
  display: none;
}

.page-about .qa-node__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--grid-line);
  background: var(--deck-blue);
  color: var(--slate);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background-color 0.2s var(--ease);
}

.page-about .qa-node__link:hover,
.page-about .qa-node__link:focus-visible {
  color: var(--cyan);
  border-color: var(--cyan-dim);
  background: var(--panel-blue);
}

.page-about .qa-node__dot {
  flex: none;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--graphite);
  transition: background-color 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.page-about .qa-node__link:hover .qa-node__dot {
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(53, 230, 210, 0.16);
}

.page-about .qa-node__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--cyan-dim);
}

/* ——— 章节 ——— */
.page-about .qa-chapter {
  padding: 36px 0;
  border-top: 1px solid var(--grid-line);
  scroll-margin-top: calc(var(--hdr-h) + 32px);
  transition: background-color 0.4s var(--ease);
}

.page-about .qa-chapter:first-child {
  border-top: 0;
  padding-top: 0;
}

.page-about .qa-chapter:target {
  background: linear-gradient(180deg, rgba(53, 230, 210, 0.055), rgba(53, 230, 210, 0));
}

.page-about .qa-chapter:target .qa-chapter__title {
  color: var(--cyan);
}

.page-about .qa-chapter__head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 20px;
}

.page-about .qa-chapter__idx {
  flex: none;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--cyan-dim);
}

.page-about .qa-chapter__title {
  margin: 0;
  font-family: var(--font-narrow);
  font-weight: 700;
  font-size: clamp(21px, 3.4vw, 33px);
  line-height: 1.26;
  letter-spacing: -0.01em;
  color: var(--cold-white);
}

.page-about .qa-lead {
  margin: 0 0 24px;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.7;
  color: var(--slate);
}

/* ——— 图片 ——— */
.page-about .qa-media {
  margin: 0 0 28px;
}

.page-about .qx-figure__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

@media (min-width: 900px) {
  .page-about .qa-media--half {
    max-width: 62%;
  }
}

/* ——— 时间线 ——— */
.page-about .qa-timeline {
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .qa-tl {
  position: relative;
  display: grid;
  gap: 6px;
  padding: 18px 0 18px 26px;
  border-left: 1px solid var(--grid-line);
}

.page-about .qa-tl::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 24px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 3px rgba(255, 194, 75, 0.12);
}

.page-about .qa-tl__year {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .qa-tl__title {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 600;
  color: var(--cold-white);
}

.page-about .qa-tl__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--slate);
}

/* ——— 团队 ——— */
.page-about .qa-team__bar {
  display: flex;
  height: 54px;
  border: 1px solid var(--grid-line);
  background: var(--deck-blue);
  overflow: hidden;
}

.page-about .qa-team__seg {
  flex: 1 1 0;
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-right: 1px solid rgba(5, 10, 24, 0.4);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 15px;
  font-weight: 600;
  transition: filter 0.2s var(--ease);
}

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

.page-about .qa-team__seg:hover {
  filter: brightness(1.16);
}

.page-about .qa-team__seg--a {
  background: var(--cyan);
  color: var(--void-navy);
}

.page-about .qa-team__seg--b {
  background: var(--cyan-dim);
  color: var(--cold-white);
}

.page-about .qa-team__seg--c {
  background: var(--orange);
  color: var(--void-navy);
}

.page-about .qa-team__seg--d {
  background: var(--graphite);
  color: var(--cold-white);
}

.page-about .qa-team__legend {
  display: grid;
  gap: 16px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .qa-team__item {
  display: grid;
  grid-template-columns: 12px minmax(0, 1fr);
  gap: 12px;
  align-items: start;
}

.page-about .qa-team__swatch {
  width: 12px;
  height: 12px;
  margin-top: 5px;
}

.page-about .qa-team__swatch--a {
  background: var(--cyan);
}

.page-about .qa-team__swatch--b {
  background: var(--cyan-dim);
}

.page-about .qa-team__swatch--c {
  background: var(--orange);
}

.page-about .qa-team__swatch--d {
  background: var(--graphite);
}

.page-about .qa-team__name {
  margin: 0 0 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--cold-white);
}

.page-about .qa-team__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.65;
  color: var(--slate);
}

/* ——— 网点 ——— */
.page-about .qa-split {
  display: grid;
  gap: 28px;
}

.page-about .qa-split__visual {
  border: 1px solid var(--grid-line);
  background: var(--deck-blue);
  padding: 20px 20px 14px;
}

.page-about .qa-map {
  display: block;
  width: 100%;
  height: auto;
}

.page-about .qa-map__cap {
  margin: 10px 0 0;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--graphite);
}

/* ——— 资质 ——— */
.page-about .qa-cert {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 26px;
}

.page-about .qa-cert__item {
  padding: 10px 14px;
  border: 1px solid var(--grid-line);
  background: var(--panel-blue);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--slate);
}

/* ——— 场景卡 ——— */
.page-about .qa-scenes {
  display: grid;
  gap: 1px;
  border: 1px solid var(--grid-line);
  background: var(--grid-line);
}

.page-about .qa-scene {
  padding: 24px 22px 22px;
  background: var(--deck-blue);
  transition: background-color 0.25s var(--ease);
}

.page-about .qa-scene:hover {
  background: var(--panel-blue);
}

.page-about .qa-scene__title {
  margin: 14px 0 8px;
  font-size: 17px;
  font-weight: 600;
  color: var(--cold-white);
}

.page-about .qa-scene p {
  margin: 0 0 16px;
  font-size: 15px;
  line-height: 1.65;
  color: var(--slate);
}

.page-about .qa-scene__link {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 230, 210, 0.4);
  padding-bottom: 2px;
}

.page-about .qa-scene__link:hover {
  color: var(--cold-white);
  border-bottom-color: var(--orange);
}

/* ——— 收尾 ——— */
.page-about .qa-closing {
  margin-top: 36px;
  padding: 32px 24px;
  border: 1px solid var(--grid-line);
  background: linear-gradient(140deg, var(--deck-blue) 0%, var(--void-navy) 100%);
}

.page-about .qa-closing__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.page-about .qa-reasons {
  display: grid;
  gap: 1px;
  background: var(--grid-line);
  border: 1px solid var(--grid-line);
}

.page-about .qa-reason {
  padding: 22px 20px;
  background: var(--deck-blue);
}

.page-about .qa-reason__num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 24px;
  line-height: 1;
  color: var(--orange);
}

.page-about .qa-reason__title {
  margin: 14px 0 8px;
  font-size: 17px;
  font-weight: 600;
  color: var(--cold-white);
}

.page-about .qa-reason p {
  margin: 0;
  font-size: 15px;
  line-height: 1.65;
  color: var(--slate);
}

/* ——— 断点 ——— */
@media (min-width: 700px) {
  .page-about .qa-hero {
    padding: 48px 0 72px;
  }

  .page-about .qa-team__legend {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px 28px;
  }

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

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

  .page-about .qa-tl {
    grid-template-columns: 92px minmax(0, 1fr);
    gap: 24px;
    padding-left: 32px;
  }

  .page-about .qa-tl::before {
    top: 26px;
  }
}

@media (min-width: 900px) {
  .page-about .qa-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 56px;
  }

  .page-about .qa-body {
    padding: 64px 0 104px;
  }

  .page-about .qa-body__grid {
    grid-template-columns: var(--qa-axis-w) minmax(0, 1fr);
    gap: 48px;
  }

  .page-about .qa-axis__rail {
    display: block;
    position: absolute;
    left: var(--qa-rail-x);
    top: 6px;
    bottom: 6px;
    width: 1px;
    background: linear-gradient(
      to bottom,
      transparent 0,
      var(--grid-line) 6%,
      var(--grid-line) 94%,
      transparent 100%
    );
  }

  .page-about .qa-axis__list {
    position: sticky;
    top: calc(var(--hdr-h) + 40px);
    flex-direction: column;
    gap: 30px;
    padding: 0;
    overflow: visible;
  }

  .page-about .qa-node__link {
    display: grid;
    grid-template-columns: 24px minmax(0, 1fr);
    grid-template-areas:
      "dot num"
      "dot label";
    gap: 2px 8px;
    align-items: center;
    padding: 0;
    border: 0;
    background: none;
    white-space: normal;
    font-size: 12px;
  }

  .page-about .qa-node__link:hover,
  .page-about .qa-node__link:focus-visible {
    background: none;
    border-color: transparent;
  }

  .page-about .qa-node__dot {
    grid-area: dot;
    justify-self: center;
  }

  .page-about .qa-node__num {
    grid-area: num;
    font-size: 13px;
  }

  .page-about .qa-node__label {
    grid-area: label;
    color: var(--slate);
    letter-spacing: 0.08em;
  }

  .page-about .qa-split {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 40px;
    align-items: start;
  }

  .page-about .qa-closing {
    padding: 40px 36px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .qa-chapter,
  .page-about .qa-node__link,
  .page-about .qa-node__dot,
  .page-about .qa-team__seg,
  .page-about .qa-scene {
    transition: none;
  }
}