.page-about {
  --about-panel-pad: clamp(18px, 2.4vw, 26px);
  --about-soft-line: rgba(155, 243, 234, 0.14);
  background: var(--ink-900);
  color: var(--text);
  font-family: var(--font-sans);
  overflow-x: hidden;
  padding-bottom: clamp(40px, 7vw, 88px);
}

.page-about .breadcrumb {
  margin-bottom: clamp(20px, 3vw, 34px);
  font-size: 12.5px;
}

.page-about .eyebrow {
  margin: 0;
  color: var(--cyan-400);
  font-size: 11.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.page-about h2 {
  margin: 14px 0 0;
  font-size: clamp(23px, 3.6vw, 36px);
  line-height: 1.28;
  letter-spacing: 0.02em;
  font-weight: 900;
  color: var(--cream-050);
}

.page-about h3 {
  margin: 0;
  font-size: clamp(16px, 1.9vw, 18.5px);
  line-height: 1.5;
  font-weight: 700;
}

.page-about p {
  line-height: 1.78;
}

.page-about a {
  color: var(--cyan-200);
  text-decoration: none;
  border-bottom: 1px solid rgba(155, 243, 234, 0.35);
}

.page-about a:hover,
.page-about a:focus-visible {
  color: var(--amber-400);
  border-bottom-color: var(--amber-400);
}

.page-about .media-frame {
  margin: 0;
  overflow: hidden;
  position: relative;
  background: var(--ink-700);
}

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

.page-about .media-frame__tag {
  position: absolute;
  left: 0;
  bottom: 0;
  display: block;
  padding: 7px 12px;
  background: rgba(11, 18, 48, 0.86);
  color: var(--cyan-200);
  font-size: 11px;
  letter-spacing: 0.1em;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(22px, 4.6vw, 54px) 0 clamp(36px, 6.4vw, 82px);
  border-bottom: 1px solid var(--about-soft-line);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right, var(--grid-line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-line) 1px, transparent 1px);
  background-size: 62px 62px;
  -webkit-mask-image: radial-gradient(120% 78% at 16% 0%, #000 18%, transparent 76%);
  mask-image: radial-gradient(120% 78% at 16% 0%, #000 18%, transparent 76%);
}

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

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(26px, 4vw, 52px);
  align-items: start;
}

.page-about .about-hero h1 {
  margin: 16px 0 0;
  font-size: clamp(29px, 5.2vw, 56px);
  line-height: 1.16;
  letter-spacing: 0.02em;
  font-weight: 900;
  color: var(--cream-050);
}

.page-about .about-hero .lede {
  margin: 20px 0 0;
  max-width: 34em;
  font-size: clamp(14.5px, 1.6vw, 16.5px);
  color: rgba(230, 233, 244, 0.86);
}

.page-about .about-hero__stats {
  display: grid;
  gap: 16px;
  margin-top: clamp(26px, 3.4vw, 36px);
  padding-top: 22px;
  border-top: 1px solid var(--about-soft-line);
}

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding-left: 12px;
  border-left: 2px solid rgba(47, 227, 208, 0.42);
}

.page-about .about-stat__num {
  font-size: clamp(21px, 2.8vw, 28px);
  font-weight: 600;
  color: var(--cyan-400);
  letter-spacing: 0.02em;
  line-height: 1.1;
}

.page-about .about-stat__label {
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--slate-300);
}

.page-about .about-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(24px, 3.2vw, 34px);
}

.page-about .about-hero__figure {
  aspect-ratio: 7 / 5;
  border-radius: 2px 30px 2px 30px;
  box-shadow: 0 0 0 1px rgba(47, 227, 208, 0.22) inset;
}

/* ---------- 章节头 ---------- */
.page-about .section {
  padding: clamp(40px, 6.4vw, 82px) 0 0;
}

.page-about .about-head {
  position: relative;
  max-width: 46em;
  padding-right: 18px;
  margin-bottom: clamp(24px, 3.4vw, 38px);
}

.page-about .about-head__text {
  margin: 14px 0 0;
  font-size: 14.5px;
  color: rgba(230, 233, 244, 0.74);
}

.page-about .about-anno {
  display: none;
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.26em;
  color: rgba(169, 179, 204, 0.62);
  text-transform: uppercase;
}

/* ---------- 02 客户处境 ---------- */
.page-about .about-problem__grid {
  display: grid;
  gap: 16px;
}

.page-about .about-problem__item {
  padding: var(--about-panel-pad);
  background: var(--cream-050);
  color: var(--brown-900);
  border-radius: 2px 20px 2px 20px;
}

.page-about .about-problem__item:nth-child(even) {
  border-radius: 20px 2px 20px 2px;
}

.page-about .about-problem__no {
  display: block;
  font-size: 11.5px;
  letter-spacing: 0.16em;
  color: rgba(42, 29, 22, 0.55);
  margin-bottom: 10px;
}

.page-about .about-problem__item h3 {
  color: var(--brown-900);
}

.page-about .about-problem__item p {
  margin: 10px 0 0;
  font-size: 13.8px;
  color: rgba(42, 29, 22, 0.82);
}

/* ---------- 03 发展历程 ---------- */
.page-about .about-history__figure {
  aspect-ratio: 16 / 9;
  margin-bottom: clamp(28px, 4vw, 44px);
  border-radius: 2px 24px 2px 24px;
}

.page-about .about-history__layout {
  display: grid;
  gap: 22px;
}

.page-about .about-years {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .about-year-link {
  display: inline-block;
  padding: 6px 11px;
  border: 1px solid var(--line-strong);
  border-radius: 2px 10px 2px 10px;
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--cyan-200);
  border-bottom: 1px solid var(--line-strong);
}

.page-about .about-year-link:hover,
.page-about .about-year-link:focus-visible {
  background: rgba(47, 227, 208, 0.14);
  color: var(--cyan-400);
}

.page-about .about-timeline {
  position: relative;
  list-style: none;
  margin: 0;
  padding: 0 0 0 22px;
  display: grid;
  gap: 14px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 10px;
  bottom: 10px;
  width: 1px;
  background: linear-gradient(180deg, var(--cyan-400), rgba(47, 227, 208, 0.08));
}

.page-about .about-tl-item {
  position: relative;
}

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: -21px;
  top: 20px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--cyan-400);
  box-shadow: 0 0 0 4px rgba(47, 227, 208, 0.14);
}

.page-about .about-node {
  background: rgba(22, 32, 74, 0.62);
  border: 1px solid var(--about-soft-line);
  border-radius: 2px 16px 2px 16px;
  padding: 14px 16px;
}

.page-about .about-node > summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  cursor: pointer;
  list-style: none;
  outline-offset: 4px;
}

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

.page-about .about-node__year {
  font-size: clamp(20px, 2.4vw, 26px);
  color: var(--cyan-400);
  letter-spacing: 0.03em;
  flex: none;
}

.page-about .about-node__title {
  font-size: 14.5px;
  font-weight: 700;
  color: var(--cream-050);
  line-height: 1.5;
}

.page-about .about-node[open] .about-node__title {
  color: var(--amber-400);
}

.page-about .about-node .fold-body p {
  margin: 12px 0 0;
  font-size: 13.6px;
  color: rgba(230, 233, 244, 0.76);
}

/* ---------- 04 团队 ---------- */
.page-about .about-team {
  margin-top: clamp(40px, 6.4vw, 82px);
  padding: clamp(38px, 6vw, 78px) 0;
  background: var(--cream-050);
  color: var(--brown-900);
}

.page-about .about-team h2 {
  color: var(--brown-900);
}

.page-about .about-team .eyebrow {
  color: #8a5a2b;
}

.page-about .about-team__grid {
  display: grid;
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}

.page-about .about-team__lead {
  margin: 14px 0 0;
  font-size: 14.5px;
  color: rgba(42, 29, 22, 0.82);
  max-width: 32em;
}

.page-about .about-team__list {
  list-style: none;
  margin: clamp(22px, 3vw, 30px) 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-team__item {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 12px;
  padding-top: 12px;
  border-top: 1px solid rgba(42, 29, 22, 0.16);
}

.page-about .about-team__num {
  font-size: 22px;
  line-height: 1.2;
  color: #0f6f66;
  font-weight: 600;
}

.page-about .about-team__item h3 {
  font-size: 15px;
  color: var(--brown-900);
}

.page-about .about-team__item p {
  margin: 5px 0 0;
  font-size: 13.2px;
  color: rgba(42, 29, 22, 0.74);
}

.page-about .about-team__figure {
  aspect-ratio: 3 / 2;
  border-radius: 22px 2px 22px 2px;
  box-shadow: 0 14px 38px rgba(42, 29, 22, 0.16);
}

/* ---------- 05 流程 ---------- */
.page-about .about-flow__bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: clamp(20px, 2.8vw, 28px);
}

.page-about .filter-btn {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  padding: 9px 14px;
  background: transparent;
  color: var(--cyan-200);
  border: 1px solid var(--line-strong);
  border-radius: 2px 12px 2px 12px;
  cursor: pointer;
  transition: background 0.18s ease, color 0.18s ease;
}

.page-about .filter-btn:hover,
.page-about .filter-btn:focus-visible {
  color: var(--amber-400);
  border-color: rgba(255, 180, 84, 0.6);
}

.page-about .filter-btn[aria-pressed="true"] {
  background: var(--cyan-400);
  border-color: var(--cyan-400);
  color: var(--ink-900);
}

.page-about .about-flow__grid {
  display: grid;
  gap: 14px;
}

.page-about [data-filter-item][hidden] {
  display: none;
}

.page-about .about-step {
  padding: var(--about-panel-pad);
  background: var(--cream-050);
  color: var(--brown-900);
  border-radius: 2px 18px 2px 18px;
  display: flex;
  flex-direction: column;
  gap: 9px;
  position: relative;
  overflow: hidden;
}

.page-about .about-step::after {
  content: "";
  position: absolute;
  right: -22px;
  top: -22px;
  width: 54px;
  height: 54px;
  background: linear-gradient(135deg, rgba(47, 227, 208, 0.32), rgba(201, 191, 232, 0.28));
  transform: rotate(45deg);
}

.page-about .about-step__no {
  font-size: 11.5px;
  letter-spacing: 0.18em;
  color: rgba(42, 29, 22, 0.5);
}

.page-about .about-step h3 {
  color: var(--brown-900);
}

.page-about .about-step p {
  margin: 0;
  font-size: 13.4px;
  color: rgba(42, 29, 22, 0.8);
}

.page-about .about-step__out {
  margin-top: auto;
  padding-top: 10px;
  border-top: 1px dashed rgba(42, 29, 22, 0.24);
  font-size: 12.6px;
  color: rgba(42, 29, 22, 0.86);
}

.page-about .about-step__out .mono {
  display: inline-block;
  margin-right: 6px;
  color: #0f6f66;
  letter-spacing: 0.1em;
}

.page-about .about-step__out a {
  color: #0f6f66;
  border-bottom-color: rgba(15, 111, 102, 0.4);
}

/* ---------- 06 资质 ---------- */
.page-about .about-cert-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 11px;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
}

.page-about .about-cert {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 15px 16px;
  background: var(--cream-050);
  color: var(--brown-900);
  border-radius: 2px 16px 2px 16px;
  font-size: 12.6px;
  line-height: 1.62;
}

.page-about .about-cert:nth-child(even) {
  border-radius: 16px 2px 16px 2px;
  background: var(--ink-700);
  color: rgba(230, 233, 244, 0.86);
  border: 1px solid var(--line-strong);
}

.page-about .about-cert__key {
  font-size: 10.5px;
  letter-spacing: 0.14em;
  color: rgba(42, 29, 22, 0.5);
}

.page-about .about-cert:nth-child(even) .about-cert__key {
  color: var(--cyan-400);
}

.page-about .about-cert strong {
  font-size: 14px;
  font-weight: 700;
}

.page-about .about-cert:nth-child(even) strong {
  color: var(--cream-050);
}

.page-about .about-trust__note {
  margin: 22px 0 0;
  font-size: 12.6px;
  color: var(--slate-300);
}

/* ---------- 07 客户类型 ---------- */
.page-about .about-clients__grid {
  display: grid;
  gap: 14px;
}

.page-about .about-client {
  position: relative;
  padding: var(--about-panel-pad);
  padding-left: calc(var(--about-panel-pad) + 10px);
  border: 1px solid var(--about-soft-line);
  border-left: 3px solid var(--cyan-400);
  border-radius: 0 18px 0 18px;
  background: linear-gradient(160deg, rgba(22, 32, 74, 0.9), rgba(11, 18, 48, 0.6));
}

.page-about .about-client:nth-child(2) {
  border-left-color: var(--mist-300);
}

.page-about .about-client:nth-child(3) {
  border-left-color: var(--amber-400);
}

.page-about .about-client .tag {
  display: inline-block;
  margin-bottom: 12px;
}

.page-about .about-client h3 {
  color: var(--cream-050);
}

.page-about .about-client p {
  margin: 10px 0 0;
  font-size: 13.4px;
  color: rgba(230, 233, 244, 0.76);
}

/* ---------- 结尾 ---------- */
.page-about .about-cta {
  padding-bottom: clamp(10px, 2vw, 24px);
}

.page-about .about-cta__frame {
  position: relative;
  overflow: hidden;
  padding: clamp(24px, 4vw, 48px);
  background: linear-gradient(135deg, var(--ink-700), var(--ink-800) 62%, rgba(201, 191, 232, 0.16));
}

.page-about .about-cta__frame::after {
  content: "";
  position: absolute;
  right: -90px;
  bottom: -110px;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(47, 227, 208, 0.22), transparent 68%);
  pointer-events: none;
}

.page-about .about-cta__frame h2 {
  margin-top: 12px;
}

.page-about .about-cta__frame p {
  margin: 14px 0 0;
  font-size: 14.2px;
  max-width: 40em;
  color: rgba(230, 233, 244, 0.82);
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
  position: relative;
  z-index: 1;
}

.page-about .about-cta__meta {
  margin-top: 18px;
  font-size: 11.5px;
  letter-spacing: 0.08em;
  color: var(--slate-300);
}

@media (min-width: 600px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }

  .page-about .about-problem__grid {
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  }

  .page-about .about-flow__grid {
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-anno {
    display: block;
    position: absolute;
    right: 0;
    top: 4px;
  }

  .page-about .about-head {
    padding-right: 46px;
  }

  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
    gap: clamp(38px, 4.4vw, 60px);
  }

  .page-about .about-hero__figure {
    margin-top: 10px;
  }

  .page-about .about-history__layout {
    grid-template-columns: 132px minmax(0, 1fr);
    gap: 44px;
  }

  .page-about .about-years {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    position: sticky;
    top: calc(var(--ruler-h) + 26px);
    align-self: start;
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  }

  .page-about .about-team__figure {
    position: sticky;
    top: calc(var(--ruler-h) + 26px);
  }

  .page-about .about-history__figure {
    aspect-ratio: 16 / 7;
  }

  .page-about .about-cert:nth-child(3n + 2) {
    transform: translateY(12px);
  }
}

@media (min-width: 1080px) {
  .page-about .about-problem__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .about-flow__grid {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .about-step p {
    font-size: 12.8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .filter-btn {
    transition: none;
  }

  .page-about .about-cert:nth-child(3n + 2) {
    transform: none;
  }
}