.page-about {
  --ab-rail: 188px;
  --ab-gap: clamp(24px, 4vw, 56px);
  --ab-sec-pad: clamp(34px, 5vw, 60px);
  display: block;
}

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

/* ---------- 首屏 ---------- */

.page-about .ab-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(22px, 4vw, 38px) 0 clamp(36px, 6vw, 68px);
  border-bottom: 1px solid var(--line);
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -12%;
  width: min(56%, 620px);
  height: 160%;
  background: var(--panel);
  clip-path: polygon(24% 0, 100% 0, 100% 100%, 0 74%);
  pointer-events: none;
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 104px;
  height: 4px;
  background: var(--brand);
}

.page-about .ab-hero > .wrap {
  position: relative;
  z-index: 1;
}

.page-about .ab-hero__title {
  margin: 14px 0 18px;
  max-width: 15em;
}

.page-about .ab-hero__lead {
  max-width: 44em;
  margin: 0;
}

.page-about .ab-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px 24px;
  margin-top: clamp(26px, 4vw, 42px);
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.page-about .ab-hero__stats .stat-value {
  display: block;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: clamp(22px, 3vw, 28px);
  line-height: 1.15;
  color: var(--text);
}

.page-about .ab-hero__stats .stat-label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--muted);
}

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

/* ---------- 主体骨架 ---------- */

.page-about .ab-shell {
  padding-top: clamp(28px, 4vw, 48px);
  padding-bottom: clamp(40px, 6vw, 84px);
}

.page-about .ab-body {
  min-width: 0;
}

@media (min-width: 960px) {
  .page-about .ab-shell {
    display: grid;
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    column-gap: var(--ab-gap);
  }
}

/* ---------- 章节索引 ---------- */

.page-about .ab-rail {
  margin-bottom: 26px;
}

.page-about .ab-rail__title {
  margin: 0 0 10px;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--muted);
}

.page-about .ab-rail__list {
  display: flex;
  gap: 6px;
  margin: 0;
  padding: 0 0 12px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  border-bottom: 1px solid var(--line);
}

.page-about .ab-rail__list::-webkit-scrollbar {
  display: none;
}

.page-about .ab-rail__link {
  display: flex;
  align-items: baseline;
  gap: 7px;
  flex: 0 0 auto;
  padding: 7px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  white-space: nowrap;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .ab-rail__link:hover {
  color: var(--text);
  border-color: var(--slate-600);
  background: var(--panel);
}

.page-about .ab-rail__link:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.page-about .ab-rail__num {
  font-size: 12px;
  color: var(--brand);
}

@media (min-width: 960px) {
  .page-about .ab-rail {
    position: sticky;
    top: calc(var(--header-h, 64px) + 20px);
    align-self: start;
    margin-bottom: 0;
    padding-left: 16px;
    border-left: 1px solid var(--line);
  }

  .page-about .ab-rail__list {
    display: block;
    overflow: visible;
    padding-bottom: 0;
    border-bottom: 0;
  }

  .page-about .ab-rail__link {
    position: relative;
    padding: 9px 0 9px 12px;
    border: 0;
    border-radius: 0;
    white-space: normal;
    line-height: 1.5;
    background: transparent;
  }

  .page-about .ab-rail__link::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    width: 2px;
    height: 0;
    background: var(--brand);
    transform: translateY(-50%);
    transition: height 160ms var(--ease);
  }

  .page-about .ab-rail__link:hover {
    background: transparent;
  }

  .page-about .ab-rail__link:hover::before,
  .page-about .ab-rail__link:focus-visible::before {
    height: 18px;
  }
}

/* ---------- 章节通用 ---------- */

.page-about .ab-sec {
  padding: var(--ab-sec-pad) 0;
}

.page-about .ab-sec + .ab-sec {
  border-top: 1px solid var(--line);
}

.page-about .ab-sec .section-head {
  margin-bottom: 20px;
}

.page-about .ab-p {
  max-width: 62ch;
  margin: 0 0 16px;
}

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

/* ---------- 三条原则 ---------- */

.page-about .ab-principles {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 22px;
}

.page-about .ab-principle {
  padding: 2px 0 2px 18px;
  border-left: 2px solid var(--brand);
}

.page-about .ab-principle__head {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.page-about .ab-principle__n {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--brand);
}

.page-about .ab-principle__title {
  margin: 0;
  font-size: var(--fs-20);
  font-weight: 700;
}

.page-about .ab-principle__body {
  margin: 8px 0 0;
  max-width: 62ch;
  color: var(--text);
  line-height: 1.75;
}

.page-about .ab-principle__act {
  margin: 10px 0 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .ab-principle__tag {
  display: inline-block;
  margin-right: 8px;
  padding: 1px 6px;
  border: 1px solid var(--orange-200);
  border-radius: var(--radius-sm);
  color: var(--orange-200);
  font-size: 11px;
  letter-spacing: 0.06em;
}

/* ---------- 服务范围 ---------- */

.page-about .ab-range {
  margin: 26px 0;
  display: grid;
  gap: 20px;
}

@media (min-width: 840px) {
  .page-about .ab-range {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: stretch;
    gap: 24px;
  }
}

.page-about .ab-map {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 200px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--panel);
  background-image: radial-gradient(circle, rgba(140, 155, 168, 0.32) 1.5px, transparent 1.6px);
  background-size: 20px 20px;
  overflow: hidden;
}

.page-about .ab-map__hl {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 108px;
  height: 80px;
  border: 1px solid var(--orange-500);
  border-radius: 12px 28px 14px 26px;
  background: rgba(255, 122, 41, 0.16);
  transform: translate(-22px, -8px);
}

.page-about .ab-map__hl-text {
  font-size: 13px;
  font-weight: 600;
  color: var(--orange-200);
}

.page-about .ab-map__tag {
  position: absolute;
  right: 14px;
  bottom: 12px;
  font-size: 11px;
  letter-spacing: 0.02em;
  color: var(--muted);
}

.page-about .ab-facts {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--line);
  overflow: hidden;
}

.page-about .ab-facts li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 13px 16px;
  background: var(--panel);
}

.page-about .ab-facts__k {
  font-size: 14px;
  color: var(--muted);
}

.page-about .ab-facts__v {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 15px;
  color: var(--text);
  white-space: nowrap;
}

/* ---------- 团队分工 ---------- */

.page-about .ab-team {
  margin-top: 26px;
  display: grid;
  gap: 24px;
}

@media (min-width: 900px) {
  .page-about .ab-team {
    grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
    align-items: start;
    gap: 32px;
  }
}

.page-about .ab-team__fig {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
}

.page-about .ab-team__fig img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-team__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .ab-team__item {
  position: relative;
  overflow: hidden;
  padding: 15px 18px 17px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  transition: border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .ab-team__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--brand);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform 180ms var(--ease);
}

.page-about .ab-team__item:hover,
.page-about .ab-team__item:focus-within {
  border-color: rgba(16, 191, 108, 0.45);
  background: #15242F;
}

.page-about .ab-team__item:hover::before,
.page-about .ab-team__item:focus-within::before {
  transform: scaleY(1);
}

.page-about .ab-team__n {
  display: block;
  font-size: 12px;
  color: var(--brand);
  letter-spacing: 0.08em;
}

.page-about .ab-team__t {
  margin: 6px 0 8px;
  font-size: var(--fs-16);
  font-weight: 700;
}

.page-about .ab-team__d {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--muted);
}

/* ---------- 三轮改版 ---------- */

.page-about .ab-rev-fig {
  margin: 26px 0 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
}

.page-about .ab-rev-fig img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .ab-rev__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
}

.page-about .ab-rev .tab {
  font: inherit;
  font-size: 14px;
  line-height: 1.4;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  transition: color 160ms var(--ease), border-color 160ms var(--ease), background-color 160ms var(--ease);
}

.page-about .ab-rev .tab:hover {
  color: var(--text);
  border-color: var(--slate-600);
  background: var(--panel);
}

.page-about .ab-rev .tab:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.page-about .ab-rev .tab[aria-selected="true"] {
  color: #05291A;
  background: var(--brand);
  border-color: var(--brand);
  font-weight: 700;
}

.page-about .ab-rev .tab-panel[hidden] {
  display: none;
}

.page-about .ab-rev__lead {
  margin: 0 0 16px;
  max-width: 62ch;
  line-height: 1.75;
  color: var(--text);
}

.page-about .ab-compare {
  display: grid;
  gap: 1px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--line);
  overflow: hidden;
}

@media (min-width: 760px) {
  .page-about .ab-compare {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.page-about .ab-compare__col {
  padding: 17px 18px 19px;
  background: var(--panel);
}

.page-about .ab-compare__col--after {
  background: #16252F;
}

.page-about .ab-compare__tag {
  display: inline-block;
  margin-bottom: 9px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
}

.page-about .ab-compare__col--before .ab-compare__tag {
  color: var(--muted);
}

.page-about .ab-compare__col--after .ab-compare__tag {
  color: var(--green-300);
}

.page-about .ab-compare__col p {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.75;
}

.page-about .ab-compare__col--before p {
  color: var(--muted);
}

.page-about .ab-compare__col--after p {
  color: var(--text);
}

/* ---------- 适合谁用 ---------- */

.page-about .ab-who {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
}

.page-about .ab-who li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 16px;
  padding: 18px 0;
  border-top: 1px solid var(--line);
}

.page-about .ab-who li:first-child {
  border-top: 0;
  padding-top: 8px;
}

.page-about .ab-who__n {
  padding-top: 3px;
  min-width: 1.4em;
  font-size: 12px;
  color: var(--brand);
}

.page-about .ab-who__t {
  margin: 0 0 7px;
  font-size: var(--fs-16);
  font-weight: 700;
}

.page-about .ab-who__d {
  margin: 0;
  max-width: 62ch;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .ab-who__d a {
  color: var(--green-300);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .ab-who__d a:hover {
  color: var(--brand);
}

/* ---------- 常见问答 ---------- */

.page-about .ab-faq {
  margin-top: 22px;
  display: grid;
  gap: 10px;
}

.page-about .ab-faq__item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  overflow: hidden;
}

.page-about .ab-faq__item[open] {
  border-color: rgba(16, 191, 108, 0.4);
}

.page-about .ab-faq__q {
  position: relative;
  cursor: pointer;
  padding: 15px 44px 15px 18px;
  font-size: var(--fs-16);
  font-weight: 700;
  line-height: 1.6;
  list-style: none;
}

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

.page-about .ab-faq__q::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--brand);
  transition: transform 160ms var(--ease);
}

.page-about .ab-faq__item[open] .ab-faq__q::after {
  content: "−";
}

.page-about .ab-faq__q:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.page-about .ab-faq__a {
  margin: 0;
  padding: 0 18px 17px;
  max-width: 62ch;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .ab-faq__a a {
  color: var(--green-300);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.page-about .ab-faq__a a:hover {
  color: var(--brand);
}

/* ---------- 收束区 ---------- */

.page-about .ab-close {
  margin-top: clamp(32px, 5vw, 56px);
  display: grid;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
}

@media (min-width: 860px) {
  .page-about .ab-close {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  }
}

.page-about .ab-close__fig {
  margin: 0;
  line-height: 0;
}

.page-about .ab-close__fig img {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 200px;
  object-fit: cover;
}

.page-about .ab-close__body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 14px;
  padding: clamp(22px, 3vw, 38px);
}

.page-about .ab-close__title {
  margin: 0;
  font-size: clamp(20px, 2.6vw, 28px);
  font-weight: 700;
  line-height: 1.4;
}

.page-about .ab-close__text {
  margin: 0;
  max-width: 46ch;
  line-height: 1.75;
  color: var(--muted);
}

.page-about .ab-close__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

/* ---------- 动效偏好 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-rail__link,
  .page-about .ab-rail__link::before,
  .page-about .ab-team__item,
  .page-about .ab-team__item::before,
  .page-about .ab-rev .tab,
  .page-about .ab-faq__q::after {
    transition: none;
  }
}
</main>