/* ===== 平台介绍页 · 作用域 .page-about ===== */

.page-about {
  --about-hairline: rgba(201, 162, 39, .30);
  --about-hairline-soft: rgba(234, 223, 200, .10);
  --about-year-col: 132px;
  --about-pulse: rgba(63, 224, 208, .16);
  overflow-x: clip;
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  isolation: isolate;
  padding-block: clamp(34px, 6vw, 84px) clamp(34px, 5vw, 72px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -34% -18% auto -18%;
  height: 80%;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(56% 84% at 12% 6%, rgba(201, 162, 39, .16), transparent 68%),
    radial-gradient(46% 66% at 88% 20%, rgba(43, 27, 74, .55), transparent 72%);
}

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(28px, 5vw, 62px);
}

.page-about .about-hero__grid {
  display: grid;
  gap: clamp(24px, 4vw, 40px);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(34px, 7.2vw, 78px);
  line-height: 1.04;
  letter-spacing: -.02em;
  color: var(--ink);
}

.page-about .about-hero__title span {
  display: block;
  color: var(--gold-hi);
}

.page-about .about-hero__lede {
  margin: 0;
  font-size: clamp(15px, 1.6vw, 17px);
  line-height: 1.85;
  color: var(--ink);
  max-width: 44ch;
}

.page-about .about-hero__facts {
  list-style: none;
  margin: clamp(32px, 5vw, 60px) 0 0;
  padding: clamp(20px, 3vw, 30px) 0 0;
  border-top: 1px solid var(--about-hairline);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px 14px;
}

.page-about .about-hero__facts li {
  display: grid;
  gap: 7px;
  min-width: 0;
}

.page-about .about-fact__num {
  font-size: clamp(24px, 4vw, 36px);
  line-height: 1;
  color: var(--gold-hi);
  letter-spacing: .02em;
}

.page-about .about-fact__unit {
  font-family: var(--font-body);
  font-size: .46em;
  letter-spacing: .06em;
  margin-left: 3px;
  color: var(--gold);
}

.page-about .about-fact__label {
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--muted);
}

@media (min-width: 760px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 22px 24px;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, .9fr);
    gap: clamp(36px, 6vw, 92px);
    align-items: end;
  }
}

/* ---------- 通用小标题 ---------- */

.page-about .about-section-head {
  max-width: 720px;
  margin-bottom: clamp(28px, 4.5vw, 50px);
}

.page-about .about-section-head h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(25px, 4vw, 42px);
  line-height: 1.16;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-section-head__note {
  margin: 14px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 58ch;
}

/* ---------- 运营节点时间轴 ---------- */

.page-about .about-timeline__banner {
  position: relative;
  margin: 0 0 clamp(30px, 5vw, 58px);
  overflow: hidden;
  border: 1px solid var(--about-hairline-soft);
}

.page-about .about-timeline__banner img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(.86) contrast(1.04);
}

.page-about .about-timeline__banner::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--gold), rgba(201, 162, 39, 0) 72%);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-tl-item {
  position: relative;
  display: grid;
  gap: 10px;
  padding: 24px 0 28px 26px;
  border-top: 1px solid var(--about-hairline-soft);
  transition: border-color 220ms var(--ease);
}

.page-about .about-tl-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--gold), rgba(201, 162, 39, .10));
}

.page-about .about-tl-item:hover {
  border-top-color: var(--about-hairline);
}

.page-about .about-tl-body h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(19px, 2.4vw, 25px);
  line-height: 1.3;
  letter-spacing: -.005em;
  color: var(--ink);
}

.page-about .about-tl-body p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--muted);
  max-width: 62ch;
}

.page-about .about-tl-detail {
  margin-top: 0;
  padding-left: 14px;
  border-left: 1px solid var(--line-cyan);
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--cyan);
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transition: max-height 260ms var(--ease), opacity 220ms var(--ease), margin-top 240ms var(--ease);
}

.page-about .about-tl-item:hover .about-tl-detail,
.page-about .about-tl-item:focus-within .about-tl-detail {
  max-height: 160px;
  opacity: 1;
  margin-top: 12px;
}

@media (min-width: 820px) {
  .page-about .about-tl-item {
    grid-template-columns: var(--about-year-col) minmax(0, 1fr);
    gap: 0 clamp(28px, 4vw, 56px);
    padding: 30px 0 36px;
  }

  .page-about .about-tl-item::before {
    display: none;
  }

  .page-about .about-tl-year {
    position: relative;
    padding-left: 24px;
    padding-top: 4px;
  }

  .page-about .about-tl-year::before {
    content: "";
    position: absolute;
    left: 0;
    top: 10px;
    bottom: -36px;
    width: 1px;
    background: linear-gradient(180deg, rgba(201, 162, 39, .55), rgba(201, 162, 39, .08));
  }

  .page-about .about-tl-item:last-child .about-tl-year::before {
    bottom: 0;
  }

  .page-about .about-tl-year::after {
    content: "";
    position: absolute;
    left: -3px;
    top: 6px;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--gold);
    box-shadow: 0 0 0 4px rgba(201, 162, 39, .12);
    transition: box-shadow 200ms var(--ease);
  }

  .page-about .about-tl-item:hover .about-tl-year::after {
    box-shadow: 0 0 0 7px rgba(201, 162, 39, .20);
  }
}

@media (hover: none) {
  .page-about .about-tl-detail {
    max-height: none;
    opacity: 1;
    margin-top: 12px;
  }
}

/* ---------- 节点与技术布局 ---------- */

.page-about .about-nodes__figure {
  position: relative;
  margin: 0 0 clamp(22px, 4vw, 40px);
  overflow: hidden;
  border: 1px solid var(--about-hairline-soft);
}

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

.page-about .about-nodes__figure .figure-caption {
  display: block;
  padding: 12px 16px;
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--muted);
  border-top: 1px solid var(--about-hairline-soft);
  background: rgba(5, 13, 12, .5);
}

.page-about .about-node-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-hairline-soft);
  border: 1px solid var(--about-hairline-soft);
}

.page-about .about-node {
  position: relative;
  background: var(--panel);
  padding: 24px 22px 26px;
  min-height: 164px;
  transition: background 200ms var(--ease);
}

.page-about .about-node:hover,
.page-about .about-node:focus-visible {
  background: var(--bg-deep-lift);
  outline: none;
}

.page-about .about-node__dot {
  display: block;
  width: 8px;
  height: 8px;
  margin-bottom: 18px;
  background: var(--cyan);
  box-shadow: 0 0 0 4px var(--about-pulse);
  animation: aboutPulse 2s ease-in-out infinite;
}

.page-about .about-node__name {
  margin: 0;
  font-family: var(--font-display);
  font-size: 22px;
  letter-spacing: .04em;
  color: var(--ink);
}

.page-about .about-node__scope {
  display: block;
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--muted);
}

.page-about .about-node__role {
  margin: 0;
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  font-size: 14px;
  line-height: 1.8;
  color: var(--cyan);
  transition: max-height 260ms var(--ease), opacity 220ms var(--ease), margin-top 240ms var(--ease);
}

.page-about .about-node:hover .about-node__role,
.page-about .about-node:focus-visible .about-node__role {
  max-height: 150px;
  opacity: 1;
  margin-top: 12px;
}

@keyframes aboutPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: .45; }
}

@media (min-width: 640px) {
  .page-about .about-node-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 1080px) {
  .page-about .about-node-list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (hover: none) {
  .page-about .about-node__role {
    max-height: none;
    opacity: 1;
    margin-top: 12px;
  }
}

/* ---------- 中段氛围带 ---------- */

.page-about .about-breath {
  margin: clamp(48px, 8vw, 108px) 0;
}

.page-about .about-breath__figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  border-top: 1px solid var(--about-hairline-soft);
  border-bottom: 1px solid var(--about-hairline-soft);
}

.page-about .about-breath__figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  filter: saturate(.8) brightness(.86);
}

.page-about .about-breath__inner {
  position: absolute;
  inset: 0;
  display: grid;
  align-content: end;
  padding: clamp(22px, 5vw, 62px);
  background: linear-gradient(180deg, rgba(10, 38, 32, .08), rgba(5, 13, 12, .88));
}

.page-about .about-breath__quote {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(19px, 3.4vw, 38px);
  line-height: 1.26;
  letter-spacing: -.01em;
  color: var(--ink);
  max-width: 26ch;
}

.page-about .about-breath__quote em {
  font-style: normal;
  color: var(--gold-hi);
}

/* ---------- 团队与分工 ---------- */

.page-about .about-team__grid {
  display: grid;
  gap: 1px;
  background: var(--about-hairline-soft);
  border: 1px solid var(--about-hairline-soft);
}

.page-about .about-team__lead {
  display: grid;
  align-content: start;
  gap: 16px;
  padding: clamp(26px, 4vw, 44px);
  background: linear-gradient(158deg, rgba(43, 27, 74, .58), rgba(20, 58, 49, .92));
}

.page-about .about-team__big {
  font-size: clamp(56px, 11vw, 104px);
  line-height: .9;
  color: var(--gold-hi);
}

.page-about .about-team__lead p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink);
  max-width: 34ch;
}

.page-about .about-team__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-hairline-soft);
}

.page-about .about-team__item {
  background: var(--panel);
  padding: 24px 24px 28px;
}

.page-about .about-team__metric {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 12px;
}

.page-about .about-team__metric .num {
  font-size: 24px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-team__metric small {
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--muted);
}

.page-about .about-team__item h3 {
  margin: 0;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: .01em;
  color: var(--ink);
}

.page-about .about-team__item p {
  margin: 8px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 700px) {
  .page-about .about-team__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-team__grid {
    grid-template-columns: minmax(0, .82fr) minmax(0, 1.18fr);
  }
}

/* ---------- 服务范围与长期承诺 ---------- */

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

.page-about .about-reach__item {
  position: relative;
  padding: 26px 24px 30px;
  background: linear-gradient(150deg, rgba(20, 58, 49, .92), rgba(10, 38, 32, .72));
  border: 1px solid var(--about-hairline-soft);
}

.page-about .about-reach__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 36px;
  height: 1px;
  background: var(--gold);
}

.page-about .about-reach__stat {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: clamp(16px, 2vw, 20px);
  font-weight: 700;
  letter-spacing: .03em;
  color: var(--gold-hi);
}

.page-about .about-reach__item h3 {
  margin: 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.page-about .about-reach__item p {
  margin: 10px 0 0;
  font-size: 14px;
  line-height: 1.85;
  color: var(--muted);
}

@media (min-width: 900px) {
  .page-about .about-reach__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 24px 28px;
  }
}

/* ---------- 后续路径 ---------- */

.page-about .about-next {
  border-top: 1px solid var(--about-hairline);
}

.page-about .about-next__inner {
  display: grid;
  gap: clamp(22px, 4vw, 42px);
}

.page-about .about-next__inner h2 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(24px, 3.6vw, 38px);
  line-height: 1.18;
  letter-spacing: -.01em;
  color: var(--ink);
}

.page-about .about-next__links {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--about-hairline-soft);
  border-top: 1px solid var(--about-hairline-soft);
  border-bottom: 1px solid var(--about-hairline-soft);
}

.page-about .about-next__links li {
  background: var(--bg-deep);
  padding: 20px 22px 22px;
  transition: background 200ms var(--ease);
}

.page-about .about-next__links li:hover {
  background: var(--panel);
}

.page-about .about-next__links a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: .01em;
  color: var(--gold-hi);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 180ms var(--ease), color 180ms var(--ease);
}

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

.page-about .about-next__links p {
  margin: 8px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 700px) {
  .page-about .about-next__links {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 900px) {
  .page-about .about-next__inner {
    grid-template-columns: minmax(0, .72fr) minmax(0, 1.28fr);
    gap: clamp(40px, 6vw, 84px);
    align-items: start;
  }
}

/* ---------- 动效降级 ---------- */

@media (prefers-reduced-motion: reduce) {
  .page-about .about-node__dot {
    animation: none;
  }

  .page-about .about-tl-item,
  .page-about .about-tl-detail,
  .page-about .about-node,
  .page-about .about-node__role,
  .page-about .about-next__links li,
  .page-about .about-next__links a {
    transition: none;
  }
}
</main>