.page-about {
  --about-rail: 0px;
  --about-gap: clamp(28px, 5vw, 40px);
}

@media (min-width: 960px) {
  .page-about {
    --about-rail: 200px;
    --about-gap: clamp(36px, 5vw, 72px);
  }
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-top: clamp(16px, 3vw, 26px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(34px, 6.5vw, 74px) 0 clamp(32px, 5.5vw, 60px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -24%;
  right: -18%;
  width: min(700px, 78vw);
  height: 158%;
  background: linear-gradient(155deg, rgba(0, 229, 255, .22), rgba(255, 107, 53, .10) 58%, rgba(11, 26, 47, 0) 100%);
  transform: skewX(-12deg);
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(44, 74, 110, .6) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(44, 74, 110, .6) 1px, transparent 1px);
  background-size: 76px 76px;
  opacity: .3;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, .95), rgba(0, 0, 0, 0) 76%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, .95), rgba(0, 0, 0, 0) 76%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  max-width: 54em;
}

.page-about .hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin: 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .hero-kicker::before {
  content: "";
  width: 28px;
  height: 1px;
  background: currentColor;
}

.page-about .hero-title {
  margin: 20px 0 0;
  font-size: clamp(27px, 5vw, 46px);
  line-height: 1.26;
  letter-spacing: .01em;
  color: var(--fog);
}

.page-about .hero-lede {
  margin: 22px 0 0;
  max-width: 36em;
  font-size: clamp(15px, 1.55vw, 17px);
  line-height: 1.92;
  color: var(--mist);
}

.page-about .hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

/* ---------- 骨架栅格 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-top: clamp(34px, 6vw, 64px);
  padding-bottom: clamp(34px, 6vw, 64px);
}

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

.page-about .about-rail {
  min-width: 0;
}

@media (min-width: 960px) {
  .page-about .about-rail {
    position: sticky;
    top: 112px;
    align-self: start;
  }
}

.page-about .about-rail-spacer {
  display: none;
}

@media (min-width: 960px) {
  .page-about .about-rail-spacer {
    display: block;
  }
}

.page-about .rail-list {
  display: flex;
  flex-wrap: nowrap;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.page-about .rail-list::-webkit-scrollbar {
  display: none;
}

@media (min-width: 960px) {
  .page-about .rail-list {
    flex-direction: column;
    gap: 2px;
    overflow: visible;
    padding: 0;
  }
}

.page-about .rail-link {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  min-height: 44px;
  padding: 6px 14px;
  border: 1px solid var(--line-600);
  color: var(--mist);
  font-size: 13.5px;
  line-height: 1.4;
  text-decoration: none;
  white-space: nowrap;
  transition: color .2s var(--ease), border-color .2s var(--ease), background-color .2s var(--ease);
}

.page-about .rail-link:hover,
.page-about .rail-link:focus-visible {
  color: var(--cyan);
  border-color: var(--cyan);
  background: rgba(0, 229, 255, .07);
  outline: none;
}

.page-about .rail-num {
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--line-600);
}

.page-about .rail-link:hover .rail-num,
.page-about .rail-link:focus-visible .rail-num {
  color: var(--cyan);
}

@media (min-width: 960px) {
  .page-about .rail-link {
    display: flex;
    width: 100%;
    padding: 10px 12px;
    border: 0;
    border-left: 2px solid var(--line-600);
    white-space: normal;
  }

  .page-about .rail-link:hover,
  .page-about .rail-link:focus-visible {
    border-left-color: var(--cyan);
    background: rgba(0, 229, 255, .06);
  }
}

.page-about .about-flow {
  min-width: 0;
}

.page-about .flow-section {
  scroll-margin-top: 120px;
}

.page-about .flow-section + .flow-section {
  margin-top: clamp(48px, 8vw, 96px);
}

/* ---------- 章节标题 ---------- */
.page-about .flow-head {
  margin-bottom: clamp(18px, 3vw, 28px);
}

.page-about .flow-head__num {
  display: block;
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .flow-head__title {
  margin: 10px 0 0;
  font-size: clamp(21px, 3.2vw, 31px);
  line-height: 1.34;
  letter-spacing: .01em;
  color: var(--fog);
}

/* ---------- 正文 ---------- */
.page-about .prose p {
  margin: 0 0 1.1em;
  font-size: 15.5px;
  line-height: 1.92;
  color: var(--mist);
}

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

.page-about .flow-more {
  margin: clamp(20px, 3vw, 30px) 0 0;
}

.page-about .flow-figure {
  margin: 0 0 clamp(20px, 3vw, 28px);
}

.page-about .figure-frame img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
}

/* ---------- 链路 ---------- */
.page-about .pipe-track {
  display: block;
  width: 100%;
  height: auto;
  margin: 4px 0 18px;
}

.page-about .pipe-list {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

@media (min-width: 760px) {
  .page-about .pipe-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }
}

.page-about .pipe-step {
  position: relative;
  padding: 18px 20px 22px;
  background: var(--ink-800);
  border: 1px solid var(--line-600);
  border-top: 2px solid var(--line-600);
  transition: transform .25s var(--ease), border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .pipe-step:hover,
.page-about .pipe-step:focus-within {
  transform: translateY(-4px);
  border-top-color: var(--cyan);
  background: var(--ink-700);
}

.page-about .pipe-step__idx {
  display: block;
  font-size: 11px;
  letter-spacing: .2em;
  color: rgba(0, 229, 255, .72);
}

.page-about .pipe-step__title {
  margin: 8px 0 0;
  font-size: 16.5px;
  line-height: 1.5;
  font-weight: 600;
  color: var(--fog);
}

.page-about .pipe-step__desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.86;
  color: var(--mist);
  transition: color .25s var(--ease);
}

.page-about .pipe-step:hover .pipe-step__desc,
.page-about .pipe-step:focus-within .pipe-step__desc {
  color: var(--fog);
}

/* ---------- 团队 ---------- */
.page-about .team-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 4vw, 36px);
}

@media (min-width: 720px) {
  .page-about .team-layout {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
    align-items: start;
  }
}

.page-about .team-figure {
  margin: 0;
}

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

@media (min-width: 720px) {
  .page-about .role-card:nth-child(2) {
    margin-left: 18px;
  }

  .page-about .role-card:nth-child(3) {
    margin-left: 36px;
  }
}

.page-about .role-card {
  position: relative;
  padding: 20px 22px 24px;
  background: var(--ink-800);
  border: 1px solid var(--line-600);
  transition: border-color .25s var(--ease), background-color .25s var(--ease);
}

.page-about .role-card::after {
  content: "";
  position: absolute;
  top: 9px;
  left: 9px;
  width: 100%;
  height: 100%;
  border: 1px solid rgba(44, 74, 110, .55);
  pointer-events: none;
}

.page-about .role-card:hover {
  border-color: rgba(0, 229, 255, .55);
  background: var(--ink-700);
}

.page-about .role-card__num {
  display: block;
  font-size: 11px;
  letter-spacing: .2em;
  color: var(--cyan);
}

.page-about .role-card__title {
  margin: 8px 0 0;
  font-size: 17px;
  line-height: 1.5;
  font-weight: 600;
  color: var(--fog);
}

.page-about .role-card__desc {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.86;
  color: var(--mist);
}

/* ---------- 浅底版本分区 ---------- */
.page-about .about-band {
  position: relative;
  background: var(--paper);
  color: var(--paper-ink);
  border-top: 1px solid var(--line-600);
  border-bottom: 1px solid var(--line-600);
  padding: clamp(38px, 6vw, 68px) 0;
  scroll-margin-top: 110px;
}

.page-about .about-band::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: min(280px, 42%);
  height: 3px;
  background: var(--coral);
}

.page-about .about-band::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: min(380px, 46vw);
  height: 100%;
  background: linear-gradient(200deg, rgba(0, 229, 255, .12), rgba(0, 229, 255, 0) 72%);
  clip-path: polygon(32% 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .about-band > .container {
  position: relative;
  z-index: 1;
}

.page-about .about-band .flow-head__num {
  color: var(--ink-700);
}

.page-about .about-band .flow-head__title {
  color: var(--paper-ink);
}

.page-about .band-lede {
  margin: 0 0 clamp(18px, 2.5vw, 28px);
  max-width: 40em;
  font-size: 15px;
  line-height: 1.9;
  color: rgba(21, 37, 56, .82);
}

.page-about .stage-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid rgba(44, 74, 110, .32);
}

.page-about .stage {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(44, 74, 110, .32);
  transition: background-color .25s var(--ease);
}

.page-about .stage:hover {
  background: rgba(0, 229, 255, .09);
}

@media (min-width: 640px) {
  .page-about .stage {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 22px;
    align-items: baseline;
    padding: 20px 4px;
  }
}

.page-about .stage__num {
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--ink-700);
}

.page-about .stage__title {
  margin: 0;
  font-size: 16.5px;
  line-height: 1.5;
  font-weight: 600;
  color: var(--paper-ink);
}

.page-about .stage__desc {
  margin: 8px 0 0;
  font-size: 14.5px;
  line-height: 1.86;
  color: rgba(21, 37, 56, .82);
}

.page-about .band-figure {
  margin: clamp(24px, 3.5vw, 38px) 0 0;
  border: 1px solid rgba(44, 74, 110, .35);
}

.page-about .band-cta {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 2px;
  border-bottom: 2px solid var(--coral);
  color: var(--paper-ink);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.page-about .band-cta:hover,
.page-about .band-cta:focus-visible {
  color: var(--ink-900);
  border-color: var(--ink-900);
  outline: none;
}

/* ---------- 服务与合作 ---------- */
.page-about .flow-section--last {
  padding-bottom: clamp(10px, 2vw, 24px);
}

.page-about .coop-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
  margin: clamp(26px, 4vw, 40px) 0 0;
}

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

.page-about .coop {
  padding: 22px 22px 24px;
  background: var(--ink-800);
  border: 1px solid var(--line-600);
  border-left: 3px solid var(--coral);
  transition: background-color .25s var(--ease), transform .25s var(--ease);
}

.page-about .coop:nth-child(2) {
  border-left-color: var(--cyan);
}

.page-about .coop:hover {
  background: var(--ink-700);
  transform: translateY(-3px);
}

.page-about .coop__label {
  display: block;
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .coop__title {
  margin: 10px 0 0;
  font-size: 18px;
  line-height: 1.5;
  font-weight: 600;
  color: var(--fog);
}

.page-about .coop__desc {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.88;
  color: var(--mist);
}

/* ---------- 焦点态 ---------- */
.page-about a:focus-visible,
.page-about button:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 降低动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .pipe-step,
  .page-about .role-card,
  .page-about .coop,
  .page-about .stage {
    transition: none;
  }

  .page-about .pipe-step:hover,
  .page-about .coop:hover {
    transform: none;
  }
}