.page-about {
  --about-pad-block: clamp(40px, 7vw, 88px);
  --about-rule: 1px solid var(--line);
  --about-hair: rgba(27, 42, 74, 0.75);
}

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

.page-about .breadcrumb {
  padding-top: clamp(16px, 3vw, 28px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  border-bottom: var(--about-rule);
  background:
    radial-gradient(120% 100% at 90% -10%, rgba(32, 227, 210, 0.14), transparent 58%),
    radial-gradient(80% 70% at 4% 110%, rgba(110, 91, 166, 0.16), transparent 60%),
    linear-gradient(180deg, var(--ink-deep), var(--ink));
}

.page-about .about-hero__inner {
  padding: clamp(28px, 5vw, 64px) 0 clamp(32px, 6vw, 72px);
}

.page-about .about-hero__kicker {
  margin: 0 0 18px;
  color: var(--muted);
}

.page-about .about-hero__title {
  margin: 0;
  font-family: var(--font-narrow);
  font-weight: 900;
  font-size: clamp(34px, 7.2vw, 76px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--text);
  max-width: 13em;
}

.page-about .about-hero__lead {
  margin: 22px 0 0;
  max-width: 44ch;
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.85;
  color: var(--muted);
}

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

.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: clamp(32px, 5vw, 56px) 0 0;
  background: var(--line);
  border: var(--about-rule);
}

.page-about .about-stat {
  padding: 16px 18px 18px;
  background: var(--ink-deep);
}

.page-about .about-stat__label {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
  text-transform: uppercase;
}

.page-about .about-stat__num {
  margin: 8px 0 0;
  font-size: clamp(30px, 5.4vw, 56px);
  line-height: 1;
  color: var(--text);
}

/* ---------- 章节骨架 ---------- */
.page-about .about-sec {
  padding: var(--about-pad-block) 0;
  border-bottom: var(--about-rule);
}

.page-about .about-sec--tinted {
  background:
    linear-gradient(180deg, rgba(14, 58, 70, 0.5), rgba(5, 11, 24, 0.1) 70%),
    var(--ink);
}

.page-about .about-sec__head {
  display: flex;
  align-items: flex-start;
  gap: clamp(14px, 2.4vw, 26px);
  flex-wrap: wrap;
}

.page-about .about-sec__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  min-width: 48px;
  height: 48px;
  padding: 0 10px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--gold);
  font-size: clamp(16px, 2.2vw, 24px);
  line-height: 1;
}

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

.page-about .about-sec__eyebrow {
  margin: 4px 0 10px;
  color: var(--muted);
}

.page-about .about-sec__title {
  margin: 0;
  max-width: 20em;
  color: var(--text);
}

.page-about .about-sec__lead {
  margin: 22px 0 0;
  max-width: 52ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-sec a {
  color: var(--cyan);
}

/* ---------- 01 业务线 ---------- */
.page-about .about-lines {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap);
  margin-top: clamp(26px, 4vw, 44px);
}

.page-about .about-line {
  padding: 22px 20px 24px;
  border: var(--about-rule);
  border-left: 2px solid var(--cyan);
  background: var(--panel);
}

.page-about .about-line--teal {
  border-left-color: var(--violet);
  background: linear-gradient(160deg, rgba(14, 58, 70, 0.85), var(--panel));
}

.page-about .about-line__kicker {
  margin: 0 0 12px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
  text-transform: uppercase;
}

.page-about .about-line--teal .about-line__kicker {
  color: var(--violet);
}

.page-about .about-line h3 {
  margin: 0 0 12px;
  color: var(--text);
}

.page-about .about-line p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-line__link {
  display: inline-block;
  margin-top: 18px;
  font-size: 14px;
  letter-spacing: 0.02em;
  text-decoration: none;
  border-bottom: 1px solid rgba(32, 227, 210, 0.4);
  padding-bottom: 2px;
}

.page-about .about-line__link:hover,
.page-about .about-line__link:focus-visible {
  border-bottom-color: var(--cyan);
}

/* ---------- 02 服务版图 ---------- */
.page-about .about-map {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 48px);
  margin-top: clamp(26px, 4vw, 44px);
  align-items: start;
}

.page-about .about-map__copy .about-sec__lead {
  margin-top: 0;
}

.page-about .about-facts {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  border-top: var(--about-rule);
}

.page-about .about-fact {
  display: grid;
  grid-template-columns: minmax(72px, auto) 1fr;
  gap: 14px;
  align-items: baseline;
  padding: 16px 12px 16px 14px;
  border-bottom: var(--about-rule);
  border-left: 2px solid transparent;
  transition: border-color 180ms var(--ease), background-color 180ms var(--ease);
}

.page-about .about-fact:hover,
.page-about .about-fact:focus-within {
  border-left-color: var(--cyan);
  background: rgba(12, 23, 48, 0.85);
}

.page-about .about-fact__v {
  font-size: clamp(20px, 3vw, 28px);
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-fact__k {
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted);
}

.page-about .about-map__note {
  margin: 22px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-map__media,
.page-about .about-timeline__media,
.page-about .about-team__media {
  position: relative;
  margin: 0;
  border: var(--about-rule);
  background: var(--panel);
  overflow: hidden;
}

.page-about .about-map__media {
  aspect-ratio: 3 / 2;
  clip-path: polygon(0 3%, 100% 0, 100% 97%, 0 100%);
  border-color: var(--cyan);
  border-color: rgba(32, 227, 210, 0.35);
}

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

.page-about .about-map__media .media__cap,
.page-about .about-timeline__media .media__cap,
.page-about .about-team__media .media__cap {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 8px 12px;
  background: rgba(3, 7, 15, 0.82);
  border-top: 1px solid var(--line);
  border-right: 1px solid var(--line);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

/* ---------- 03 发展历程 ---------- */
.page-about .about-timeline__media {
  aspect-ratio: 2 / 1;
  margin-top: clamp(26px, 4vw, 44px);
}

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

.page-about .about-timeline {
  margin-top: clamp(26px, 4vw, 40px);
  padding-left: clamp(16px, 3vw, 32px);
  border-left: 1px solid var(--line);
}

.page-about .about-stage {
  border-bottom: var(--about-rule);
}

.page-about .about-stage > summary {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-stage > summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--muted);
}

.page-about .about-stage[open] > summary::after {
  content: "–";
  color: var(--cyan);
}

.page-about .about-stage__node {
  width: 10px;
  height: 10px;
  flex: 0 0 auto;
  border: 1px solid var(--gold);
  background: transparent;
  transition: background-color 180ms var(--ease);
}

.page-about .about-stage[open] .about-stage__node {
  background: var(--gold);
}

.page-about .about-stage__year {
  font-size: clamp(18px, 2.4vw, 24px);
  color: var(--text);
}

.page-about .about-stage__name {
  font-family: var(--font-narrow);
  font-weight: 700;
  font-size: clamp(15px, 1.8vw, 18px);
  color: var(--muted);
}

.page-about .about-stage__body {
  padding: 0 0 22px;
  max-width: 60ch;
}

.page-about .about-stage__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
}

/* ---------- 04 团队 ---------- */
.page-about .about-team {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 48px);
  margin-top: clamp(26px, 4vw, 44px);
  align-items: start;
}

.page-about .about-team__copy .about-sec__lead {
  margin-top: 0;
}

.page-about .about-roles {
  margin-top: 24px;
  border-top: var(--about-rule);
}

.page-about .about-role {
  border-bottom: var(--about-rule);
}

.page-about .about-role > summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 0;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-role > summary::after {
  content: "＋";
  margin-left: auto;
  font-size: 14px;
  color: var(--muted);
}

.page-about .about-role[open] > summary::after {
  content: "－";
  color: var(--cyan);
}

.page-about .about-role__dot {
  width: 6px;
  height: 6px;
}

.page-about .about-role__name {
  font-family: var(--font-narrow);
  font-weight: 700;
  font-size: 16px;
  color: var(--text);
}

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

.page-about .about-role__body {
  padding: 0 0 18px 18px;
  max-width: 56ch;
}

.page-about .about-role__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-team__note {
  margin: 24px 0 0;
  padding: 18px 18px 18px 20px;
  border: var(--about-rule);
  border-left: 2px solid var(--gold);
  background: var(--panel);
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-team__media {
  aspect-ratio: 12 / 7;
}

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

/* ---------- 05 合作 ---------- */
.page-about .about-coop-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 52px);
  margin-top: clamp(26px, 4vw, 44px);
  align-items: start;
}

.page-about .about-coop {
  border: var(--about-rule);
  border-left: 2px solid var(--cyan);
  background: var(--panel);
  margin-bottom: 14px;
}

.page-about .about-coop > summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 18px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .about-coop > summary::after {
  content: "＋";
  margin-left: auto;
  font-family: var(--font-mono);
  color: var(--muted);
}

.page-about .about-coop[open] > summary::after {
  content: "－";
  color: var(--orange);
}

.page-about .about-coop__name {
  font-family: var(--font-narrow);
  font-weight: 700;
  font-size: clamp(16px, 1.8vw, 18px);
  color: var(--text);
}

.page-about .about-coop__body {
  padding: 0 18px 20px;
}

.page-about .about-coop__body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}

.page-about .about-flow-title {
  margin: 0 0 16px;
  color: var(--orange);
}

.page-about .about-flow {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: none;
}

.page-about .about-flow li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  padding: 18px 0;
  border-top: var(--about-rule);
}

.page-about .about-flow li:last-child {
  border-bottom: var(--about-rule);
}

.page-about .about-flow__num {
  font-size: 18px;
  line-height: 1.2;
  color: var(--orange);
}

.page-about .about-flow h3 {
  margin: 0 0 8px;
  color: var(--text);
}

.page-about .about-flow p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

/* ---------- 06 资质与联系 ---------- */
.page-about .about-cred {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 4vw, 48px);
  margin-top: clamp(26px, 4vw, 44px);
}

.page-about .about-cred__list {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  border-top: var(--about-rule);
}

.page-about .about-cred__list li {
  position: relative;
  padding: 14px 0 14px 18px;
  border-bottom: var(--about-rule);
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .about-cred__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 21px;
  width: 6px;
  height: 6px;
  background: var(--gold);
}

.page-about .about-contact__rows {
  margin: 16px 0 0;
  border-top: var(--about-rule);
}

.page-about .about-contact__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 14px 0;
  border-bottom: var(--about-rule);
}

.page-about .about-contact__row dt {
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .about-contact__row dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text);
  word-break: break-word;
}

.page-about .about-contact__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

/* ---------- 桌面端 ---------- */
@media (min-width: 860px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-lines {
    grid-template-columns: 1.15fr 1fr 0.95fr;
    align-items: stretch;
  }

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

  .page-about .about-team {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  }

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

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

  .page-about .about-contact__row {
    grid-template-columns: 110px minmax(0, 1fr);
    gap: 16px;
    align-items: baseline;
  }

  .page-about .about-team__media {
    position: sticky;
    top: 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-fact,
  .page-about .about-stage__node {
    transition: none;
  }
}