.page-about {
  --ab-line: #D8E3EC;
  background: var(--cloud);
  color: var(--ink);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: calc(var(--header-h) + 48px) 0 0;
  background:
    radial-gradient(1100px 400px at 80% -10%, rgba(58, 124, 165, 0.20), rgba(58, 124, 165, 0) 72%),
    linear-gradient(180deg, #E9F1F7 0%, var(--cloud) 82%);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(0deg, var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 48px 48px;
  opacity: 0.26;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 76%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.9), transparent 76%);
  pointer-events: none;
}

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

.page-about .crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--ink-mute);
  margin-bottom: 20px;
}

.page-about .crumbs a {
  color: var(--ink-soft);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--ease), color var(--ease);
}

.page-about .crumbs a:hover {
  color: var(--sky-deep);
  border-bottom-color: var(--green);
}

.page-about .about-h1 {
  margin: 14px 0 0;
  font-size: clamp(32px, 6.2vw, 72px);
  line-height: 1.06;
  letter-spacing: -0.03em;
  font-weight: 900;
  color: var(--ink-brown);
  max-width: 17ch;
}

.page-about .about-lede {
  margin: 22px 0 0;
  max-width: 44em;
  font-size: clamp(16px, 1.5vw, 18px);
  line-height: 1.85;
  color: var(--ink);
}

.page-about .about-hero__meta {
  margin: 18px 0 0;
  max-width: 46em;
  padding-left: 16px;
  border-left: 3px solid var(--flame);
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .about-hero__banner {
  position: relative;
  z-index: 1;
  margin: clamp(30px, 5vw, 56px) 0 0;
  border-radius: 20px 20px 20px 6px;
  overflow: hidden;
  border: 1px solid var(--mist);
  background: var(--mist);
  aspect-ratio: 16 / 5;
}

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

/* ---------- 主体 4/8 分栏 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  padding: clamp(44px, 6vw, 84px) 0 clamp(56px, 7vw, 96px);
}

/* 左侧索引 */
.page-about .about-index {
  border-top: 2px solid var(--ink-brown);
  padding-top: 14px;
}

.page-about .about-index__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--ink-mute);
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
}

.page-about .about-index__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 6px 2px 7px;
  font-size: 14px;
  font-weight: 500;
  color: var(--ink-soft);
  text-decoration: none;
  transition: color var(--ease);
}

.page-about .about-index__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--green);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--ink-brown);
}

.page-about .about-index__link:hover::after,
.page-about .about-index__link:focus-visible::after {
  transform: scaleX(1);
}

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

/* ---------- 内容区块 ---------- */
.page-about .about-block {
  border-top: 1px solid var(--mist);
  padding-top: clamp(22px, 3vw, 34px);
  margin-top: clamp(40px, 5vw, 64px);
  scroll-margin-top: calc(var(--header-h) + 24px);
}

.page-about .about-block:first-child {
  margin-top: 0;
}

.page-about .about-block__title {
  margin: 10px 0 0;
  font-size: clamp(23px, 3.2vw, 34px);
  line-height: 1.22;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--ink-brown);
}

.page-about .about-block__desc {
  margin: 14px 0 0;
  max-width: 42em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}

/* ---------- 01 三条业务线 ---------- */
.page-about .line-cards {
  display: grid;
  gap: 16px;
  margin-top: 26px;
}

.page-about .line-card {
  position: relative;
  padding: 20px 20px 22px;
  border: 1px solid var(--mist);
  border-radius: var(--radius-organic);
  background: var(--cream);
  transition: border-color var(--ease), transform var(--ease), box-shadow var(--ease);
}

.page-about .line-card:hover {
  border-color: var(--green);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.page-about .line-card__no {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--flame);
}

.page-about .line-card__title {
  margin: 8px 0 6px;
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink-brown);
}

.page-about .line-card__for {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.02em;
  color: var(--sky-deep);
}

.page-about .line-card__desc {
  margin: 12px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .line-card__link {
  display: inline-block;
  margin-top: 16px;
  font-size: 14px;
  font-weight: 600;
  color: var(--sky-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--grid);
  padding-bottom: 2px;
  transition: color var(--ease), border-color var(--ease);
}

.page-about .line-card__link:hover {
  color: var(--ink-brown);
  border-bottom-color: var(--green);
}

/* ---------- 02 发展阶段 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 28px 0 0;
  padding: 0 0 0 36px;
  position: relative;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 8px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--grid), var(--mist));
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: 30px;
}

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

.page-about .timeline__tick {
  position: absolute;
  left: -36px;
  top: 2px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 10px;
  background: var(--cloud);
  border: 1px solid var(--grid);
  color: var(--sky-deep);
  transition: background var(--ease), border-color var(--ease), color var(--ease);
}

.page-about .timeline__item:hover .timeline__tick {
  background: var(--green);
  border-color: var(--green);
  color: var(--ink);
}

.page-about .timeline__name {
  margin: 0;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink-brown);
}

.page-about .timeline__line {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .timeline__brief {
  margin: 10px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--sky);
  font-family: var(--font-serif);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-brown);
}

/* ---------- 03 团队构成 ---------- */
.page-about .team-bar {
  display: flex;
  margin-top: 26px;
  height: 66px;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--mist);
}

.page-about .team-bar__seg {
  flex: var(--flex) 1 0;
  min-width: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 3px;
  padding: 0 14px;
  transition: filter var(--ease);
}

.page-about .team-bar__seg:hover {
  filter: brightness(1.06);
}

.page-about .team-bar__seg b {
  font-size: 16px;
  font-weight: 700;
  line-height: 1;
}

.page-about .team-bar__seg i {
  font-style: normal;
  font-size: 12px;
  line-height: 1.2;
  opacity: 0.88;
}

.page-about .team-bar__seg--dev {
  --flex: 190;
  background: var(--sky);
  color: #ffffff;
}

.page-about .team-bar__seg--svc {
  --flex: 96;
  background: var(--sky-deep);
  color: #ffffff;
}

.page-about .team-bar__seg--ops {
  --flex: 54;
  background: var(--grid);
  color: var(--ink-brown);
}

.page-about .team-body {
  display: grid;
  gap: 24px;
  margin-top: 28px;
}

.page-about .team-detail {
  min-width: 0;
}

/* 图片容器 */
.page-about .about-figure {
  margin: 0;
  border: 1px solid var(--mist);
  border-radius: var(--radius-organic);
  overflow: hidden;
  background: var(--mist);
}

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

.page-about .about-figure__caption {
  padding: 10px 14px 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
  color: var(--ink-mute);
  background: var(--cream);
  border-top: 1px solid var(--mist);
}

.page-about .about-figure--wide {
  margin-top: 24px;
}

/* 折叠 */
.page-about .acc {
  border-bottom: 1px solid var(--mist);
}

.page-about .acc:first-child {
  border-top: 1px solid var(--mist);
}

.page-about .acc summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 0;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 700;
  color: var(--ink-brown);
  transition: color var(--ease);
}

.page-about .acc summary::-webkit-details-marker {
  display: none;
}

.page-about .acc summary::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--flame);
  width: 14px;
  flex: none;
}

.page-about .acc[open] summary::before {
  content: "\2013";
}

.page-about .acc summary:hover {
  color: var(--sky-deep);
}

.page-about .acc__body {
  padding: 0 0 16px 24px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

/* ---------- 04 资质与安全 ---------- */
.page-about .cert-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 26px;
}

.page-about .cert {
  position: relative;
  overflow: hidden;
  min-height: 148px;
  padding: 18px;
  border: 1px solid var(--grid);
  border-radius: 5px;
  background: var(--cloud);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: border-color var(--ease), background var(--ease);
}

.page-about .cert:hover {
  border-color: var(--sky-deep);
}

.page-about .cert__mark {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--flame);
}

.page-about .cert__name {
  margin: 12px 0 0;
  font-size: 16px;
  font-weight: 800;
  line-height: 1.35;
  color: var(--ink-brown);
}

.page-about .cert__use {
  position: absolute;
  inset: 0;
  margin: 0;
  display: flex;
  align-items: center;
  padding: 18px;
  background: var(--sky-deep);
  color: var(--cream);
  font-size: 13.5px;
  line-height: 1.75;
  opacity: 0;
  transition: opacity var(--ease);
}

.page-about .cert:hover .cert__use,
.page-about .cert:focus-within .cert__use {
  opacity: 1;
}

/* ---------- 05 合作生态 ---------- */
.page-about .eco-grid {
  display: grid;
  gap: 20px;
  margin-top: 26px;
}

.page-about .eco {
  padding-top: 16px;
  border-top: 2px solid var(--ink-brown);
}

.page-about .eco__no {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--flame);
}

.page-about .eco__title {
  margin: 8px 0 0;
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink-brown);
}

.page-about .eco__desc {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .eco-note {
  margin: 28px 0 0;
  padding: 20px 22px;
  background: var(--paper);
  border-left: 3px solid var(--flame);
  border-radius: 4px 14px 14px 14px;
  font-family: var(--font-serif);
  font-size: 15px;
  line-height: 1.9;
  color: var(--ink-brown);
}

/* ---------- 06 服务承诺 ---------- */
.page-about .flow-grid {
  display: grid;
  margin-top: 26px;
  border-top: 1px solid var(--mist);
}

.page-about .flow-step {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  padding: 20px 0 22px;
  border-bottom: 1px solid var(--mist);
}

.page-about .flow-step__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--grid);
  transition: color var(--ease);
}

.page-about .flow-step:hover .flow-step__no {
  color: var(--green);
}

.page-about .flow-step__title {
  margin: 0;
  font-size: 17px;
  font-weight: 800;
  color: var(--ink-brown);
}

.page-about .flow-step__desc {
  margin: 9px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .flow-step__meta {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.03em;
  color: var(--sky-deep);
}

/* 行动区 */
.page-about .about-cta {
  position: relative;
  overflow: hidden;
  margin-top: 36px;
  padding: 26px 24px;
  border-radius: var(--radius);
  background: var(--ink);
  color: var(--on-dark);
  display: grid;
  gap: 20px;
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(0deg, rgba(169, 196, 214, 0.22) 1px, transparent 1px),
    linear-gradient(90deg, rgba(169, 196, 214, 0.22) 1px, transparent 1px);
  background-size: 40px 40px;
  -webkit-mask-image: radial-gradient(circle at 85% 15%, rgba(0, 0, 0, 0.9), transparent 68%);
  mask-image: radial-gradient(circle at 85% 15%, rgba(0, 0, 0, 0.9), transparent 68%);
  pointer-events: none;
}

.page-about .about-cta__text,
.page-about .about-cta__actions {
  position: relative;
  z-index: 1;
}

.page-about .about-cta__title {
  margin: 0;
  font-size: 21px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--cream);
}

.page-about .about-cta__desc {
  margin: 10px 0 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--on-dark-soft);
  max-width: 40em;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-cta .btn--primary {
  background: var(--green);
  border-color: var(--green);
  color: var(--ink);
}

.page-about .about-cta .btn--primary:hover {
  background: #2FBF6F;
  border-color: #2FBF6F;
  color: var(--ink);
}

.page-about .about-cta .btn--outline {
  color: var(--on-dark);
  border-color: var(--on-dark-soft);
  background: transparent;
}

.page-about .about-cta .btn--outline:hover {
  color: var(--cream);
  border-color: var(--green);
}

/* ---------- 淡入 ---------- */
.page-about .about-block[data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.page-about .about-block[data-reveal].is-in {
  opacity: 1;
  transform: none;
}

/* ---------- 响应式 ---------- */
@media (min-width: 760px) {
  .page-about .line-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .line-card:nth-child(2) {
    margin-top: 22px;
  }

  .page-about .eco-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
  }

  .page-about .cert-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }

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

  .page-about .flow-step:nth-child(odd) {
    padding-right: 28px;
    border-right: 1px solid var(--mist);
  }

  .page-about .flow-step:nth-child(even) {
    padding-left: 28px;
  }

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    padding: 32px 34px;
  }
}

@media (min-width: 900px) {
  .page-about .about-shell {
    grid-template-columns: minmax(190px, 4fr) minmax(0, 8fr);
    gap: clamp(32px, 4vw, 64px);
  }

  .page-about .about-index {
    position: sticky;
    top: calc(var(--header-h) + 32px);
    align-self: start;
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0;
  }

  .page-about .about-index__link {
    font-size: 15px;
  }

  .page-about .team-body {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 30px;
    align-items: start;
  }

  .page-about .about-figure--wide {
    margin-top: 28px;
  }
}

@media (max-width: 600px) {
  .page-about .team-bar__seg i {
    display: none;
  }

  .page-about .team-bar {
    height: 46px;
  }

  .page-about .team-bar__seg {
    padding: 0 8px;
    align-items: center;
  }

  .page-about .cert {
    min-height: 132px;
    padding: 15px;
  }

  .page-about .timeline {
    padding-left: 30px;
  }

  .page-about .timeline__tick {
    left: -30px;
    width: 19px;
    height: 19px;
    font-size: 9px;
  }

  .page-about .timeline::before {
    left: 9px;
  }
}

@media (hover: none) {
  .page-about .cert__use {
    position: static;
    inset: auto;
    opacity: 1;
    margin-top: 12px;
    padding: 0;
    background: transparent;
    color: var(--ink-soft);
    font-size: 13px;
    line-height: 1.7;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-block[data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .page-about .timeline__brief {
    max-height: none;
    opacity: 1;
    margin-top: 10px;
  }

  .page-about .line-card:hover,
  .page-about .line-card__link:hover,
  .page-about .team-bar__seg:hover {
    transform: none;
    filter: none;
  }
}