.page-about {
  --about-diag: repeating-linear-gradient(112deg, rgba(25, 227, 198, .055) 0 1px, transparent 1px 24px);
  --about-tint: #132738;
  background: var(--bg);
  color: var(--text);
  overflow-x: hidden;
}

.page-about .shell {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

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

.page-about h2 {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 5.4vw, 36px);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -.02em;
  color: var(--text);
}

.page-about .arrow-link-row {
  margin: 20px 0 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(26px, 6vw, 60px) 0 clamp(34px, 6vw, 72px);
  border-bottom: 2px solid var(--line);
  background:
    linear-gradient(112deg, rgba(15, 61, 46, .9) 0%, rgba(15, 61, 46, .22) 46%, rgba(10, 20, 32, 0) 72%),
    var(--bg);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: var(--about-diag);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(22px, 5vw, 48px);
}

.page-about .about-hero h1 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 7.6vw, 56px);
  line-height: 1.08;
  letter-spacing: -.02em;
  max-width: 15ch;
}

.page-about .about-hero__lede {
  margin: 16px 0 0;
  max-width: 34em;
  font-size: clamp(15px, 3.6vw, 17px);
  line-height: 1.85;
  color: var(--text);
}

.page-about .about-hero__jump {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 24px 0 0;
}

.page-about .about-hero__visual {
  position: relative;
  min-height: 208px;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  background:
    linear-gradient(158deg, rgba(15, 61, 46, .9) 0%, rgba(10, 20, 32, .45) 62%),
    var(--panel);
  overflow: hidden;
}

.page-about .about-hero__visual::after {
  content: "";
  position: absolute;
  left: -12%;
  top: 56%;
  width: 128%;
  height: 2px;
  background: linear-gradient(90deg, rgba(25, 227, 198, 0), var(--neon), rgba(25, 227, 198, 0));
  transform: rotate(-14deg);
  opacity: .55;
}

.page-about .hero-plate {
  position: absolute;
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin: 0;
  padding: 8px 12px;
  border: 2px solid var(--line);
  background: rgba(5, 13, 22, .88);
}

.page-about .hero-plate__k {
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .hero-plate__v {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(24px, 7.6vw, 42px);
  line-height: 1;
  color: var(--text);
}

.page-about .hero-plate--top { left: 6%; top: 9%; }
.page-about .hero-plate--mid { right: 6%; top: 37%; border-color: var(--neon); }
.page-about .hero-plate--mid .hero-plate__v { color: var(--neon); }
.page-about .hero-plate--bottom { left: 18%; bottom: 9%; border-color: var(--pulse); }
.page-about .hero-plate--bottom .hero-plate__v { color: var(--pulse); }

/* ---------- 起点 ---------- */
.page-about .about-origin {
  padding: clamp(36px, 8vw, 64px) 0 clamp(28px, 6vw, 48px);
  background: var(--bg);
}

.page-about .about-origin__inner {
  display: grid;
  gap: clamp(24px, 5vw, 44px);
}

.page-about .about-origin__text p {
  margin: 14px 0 0;
  max-width: 34em;
  line-height: 1.85;
  color: var(--text);
}

.page-about .origin-tags {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 22px 0 0;
  padding: 0;
}

.page-about .about-origin__media {
  margin: 0;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  background: var(--panel);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-line {
  padding: clamp(38px, 8vw, 74px) 0 clamp(36px, 7vw, 64px);
  border-bottom: 2px solid var(--line);
  background:
    linear-gradient(180deg, rgba(16, 31, 46, 0) 0%, rgba(16, 31, 46, .62) 14%, rgba(16, 31, 46, .62) 86%, rgba(16, 31, 46, 0) 100%),
    var(--bg);
}

.page-about .about-line__head {
  max-width: 44em;
}

.page-about .about-line__note {
  margin: 12px 0 0;
  max-width: 34em;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: clamp(26px, 5vw, 46px) 0 0;
  padding: 0;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: linear-gradient(180deg, var(--neon) 0%, var(--neon-deep) 42%, var(--line) 100%);
  opacity: .85;
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 clamp(28px, 5.5vw, 46px) 52px;
}

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

.page-about .timeline__dot {
  position: absolute;
  left: 8px;
  top: 6px;
  box-sizing: border-box;
  width: 16px;
  height: 16px;
  background: var(--panel);
  border: 2px solid var(--neon);
  box-shadow: 0 0 0 4px rgba(25, 227, 198, .12);
}

.page-about .timeline__ver {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(28px, 7.4vw, 38px);
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--muted);
  transition: color .35s var(--ease), text-shadow .35s var(--ease);
}

.page-about .timeline__item.is-visible .timeline__ver {
  color: var(--neon);
  text-shadow: 0 0 18px rgba(25, 227, 198, .38);
}

.page-about .timeline__content h3 {
  margin: 8px 0 0;
  font-size: clamp(18px, 4.4vw, 23px);
  font-weight: 800;
  line-height: 1.32;
  letter-spacing: -.01em;
  color: var(--text);
}

.page-about .timeline__content p {
  margin: 10px 0 0;
  max-width: 34em;
  line-height: 1.8;
  color: var(--text);
}

/* ---------- 可展开组 ---------- */
.page-about .disclosure {
  margin-top: 16px;
  border: 2px solid var(--line);
  background: var(--panel);
  box-shadow: var(--shadow-hard-sm);
  transition: box-shadow .25s var(--ease);
}

.page-about .disclosure[open] {
  box-shadow: var(--shadow-hard-sm), inset 3px 0 0 var(--neon);
}

.page-about .disclosure__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--neon);
}

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

.page-about .disclosure__arrow {
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid currentColor;
  border-bottom: 2px solid currentColor;
  transform: rotate(45deg);
  transition: transform .25s var(--ease);
}

.page-about .disclosure[open] .disclosure__arrow {
  transform: rotate(-135deg);
}

.page-about .disclosure__body {
  padding: 0 16px 16px;
}

.page-about .disclosure__body ul {
  margin: 0;
  padding-left: 18px;
  display: grid;
  gap: 8px;
  line-height: 1.75;
  color: var(--text);
}

.page-about .disclosure__body li::marker {
  color: var(--neon);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: clamp(40px, 8vw, 80px) 0;
  background:
    linear-gradient(200deg, rgba(15, 61, 46, .5) 0%, rgba(10, 20, 32, 0) 58%),
    var(--bg);
}

.page-about .about-team__inner {
  display: grid;
  gap: clamp(24px, 5vw, 44px);
}

.page-about .about-team__media {
  margin: 0;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  background: var(--panel);
}

.page-about .about-team__text p {
  margin: 14px 0 0;
  max-width: 34em;
  line-height: 1.85;
  color: var(--text);
}

.page-about .about-team__text a {
  color: var(--neon);
}

.page-about .ops-stats {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(118px, 1fr));
  gap: 1px;
  margin: 26px 0 0;
  padding: 0;
  border: 2px solid var(--line);
  background: var(--line);
}

.page-about .ops-stats .stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 14px 18px;
  background: var(--panel);
}

.page-about .stat__value {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(22px, 5vw, 30px);
  line-height: 1;
  color: var(--neon);
}

.page-about .stat__label {
  font-size: 13px;
  line-height: 1.5;
  color: var(--muted);
}

/* ---------- 服务覆盖 ---------- */
.page-about .about-reach {
  padding: clamp(44px, 9vw, 90px) 0;
  border-top: 2px solid var(--line);
  border-bottom: 2px solid var(--line);
  background: var(--bg);
}

.page-about .about-reach__inner {
  display: grid;
  gap: clamp(30px, 6vw, 52px);
}

.page-about .node-map {
  position: relative;
  width: 100%;
  min-height: 230px;
  aspect-ratio: 21 / 11;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  background-color: var(--panel);
  background-image: radial-gradient(circle, rgba(34, 52, 74, .95) 1.2px, transparent 1.5px);
  background-size: 18px 18px;
}

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

.page-about .node-map__item {
  position: absolute;
  display: block;
  transform: translate(-50%, -50%);
  outline: none;
}

.page-about .node-map__item--gz { left: 63%; top: 34%; }
.page-about .node-map__item--sh { left: 80%; top: 60%; }
.page-about .node-map__item--cd { left: 25%; top: 48%; }

.page-about .node-map__dot {
  display: block;
  box-sizing: border-box;
  width: 12px;
  height: 12px;
  border: 2px solid var(--neon);
  background: rgba(25, 227, 198, .25);
  box-shadow: 0 0 0 5px rgba(25, 227, 198, .1);
  transition: background .22s var(--ease), box-shadow .22s var(--ease);
}

.page-about .node-map__item:hover .node-map__dot,
.page-about .node-map__item:focus .node-map__dot {
  background: var(--neon);
  box-shadow: 0 0 0 8px rgba(25, 227, 198, .18);
}

.page-about .node-map__name {
  display: block;
  margin-top: 8px;
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--muted);
  white-space: nowrap;
}

.page-about .node-map__tip {
  position: absolute;
  left: 50%;
  bottom: calc(100% + 6px);
  z-index: 4;
  width: max-content;
  max-width: min(198px, 60vw);
  padding: 8px 10px;
  border: 2px solid var(--neon);
  background: var(--dark);
  color: var(--text);
  font-size: 12px;
  line-height: 1.55;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translate(-50%, 8px);
  transition: opacity .2s var(--ease), transform .2s var(--ease), visibility .2s linear;
}

.page-about .node-map__item:hover .node-map__tip,
.page-about .node-map__item:focus .node-map__tip {
  opacity: 1;
  visibility: visible;
  transform: translate(-50%, 0);
}

.page-about .about-reach__text p {
  margin: 14px 0 0;
  max-width: 34em;
  line-height: 1.85;
  color: var(--text);
}

/* ---------- 长期做法 ---------- */
.page-about .about-holds {
  padding: clamp(44px, 9vw, 90px) 0;
  background:
    linear-gradient(160deg, rgba(15, 61, 46, .62) 0%, rgba(10, 20, 32, .15) 60%),
    var(--bg);
}

.page-about .about-holds__head {
  max-width: 40em;
}

.page-about .holds {
  list-style: none;
  display: grid;
  gap: 1px;
  margin: clamp(26px, 5vw, 46px) 0 0;
  padding: 0;
  border: 2px solid var(--line);
  background: var(--line);
}

.page-about .holds__item {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: clamp(20px, 4vw, 30px) clamp(18px, 3.5vw, 26px);
  background: var(--panel);
  transition: background .26s var(--ease);
}

.page-about .holds__item:hover {
  background: var(--about-tint);
}

.page-about .holds__no {
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--neon);
}

.page-about .holds__item h3 {
  margin: 0;
  font-size: clamp(17px, 4vw, 20px);
  font-weight: 800;
  line-height: 1.35;
  color: var(--text);
}

.page-about .holds__item p {
  margin: 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
}

.page-about .holds__item .arrow-link {
  display: inline-block;
  margin-top: 10px;
  color: var(--neon);
}

/* ---------- 后续入口 ---------- */
.page-about .about-next {
  padding: clamp(48px, 10vw, 96px) 0 clamp(36px, 7vw, 64px);
  background: var(--bg);
}

.page-about .about-next__head {
  max-width: 40em;
}

.page-about .about-next__list {
  list-style: none;
  margin: clamp(22px, 4vw, 34px) 0 0;
  padding: 0;
  border-top: 2px solid var(--line);
}

.page-about .about-next__list .index-item {
  border-bottom: 2px solid var(--line);
}

.page-about .about-next__list .index-item__text {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 18px 6px;
  color: var(--text);
  text-decoration: none;
  transition: background .22s var(--ease), color .22s var(--ease), padding-left .22s var(--ease);
}

.page-about .about-next__list .index-item__text:hover,
.page-about .about-next__list .index-item__text:focus-visible {
  background: rgba(25, 227, 198, .07);
  padding-left: 14px;
  color: var(--neon);
}

.page-about .index-item__no {
  flex: 0 0 auto;
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--neon);
}

.page-about .about-next__label {
  font-size: clamp(15px, 3.8vw, 17px);
  line-height: 1.6;
}

.page-about .index-item__arrow {
  margin-left: auto;
  flex: 0 0 auto;
  font-size: 18px;
  color: var(--neon);
  transition: transform .25s var(--ease);
}

.page-about .about-next__list .index-item__text:hover .index-item__arrow,
.page-about .about-next__list .index-item__text:focus-visible .index-item__arrow {
  transform: translateX(6px);
}

.page-about .about-next__media {
  margin: clamp(28px, 5vw, 44px) 0 0;
  border: 2px solid var(--line);
  box-shadow: var(--shadow-hard);
  background: var(--panel);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-hero__visual {
    min-height: 290px;
  }
}

@media (min-width: 880px) {
  .page-about .timeline__item {
    display: grid;
    grid-template-columns: 104px minmax(0, 1fr);
    gap: 0 clamp(20px, 4vw, 42px);
    padding-left: 62px;
  }

  .page-about .timeline__ver {
    grid-column: 1;
    grid-row: 1;
    text-align: right;
    font-size: clamp(36px, 4.6vw, 56px);
  }

  .page-about .timeline__content {
    grid-column: 2;
    grid-row: 1;
    min-width: 0;
  }

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

@media (min-width: 920px) {
  .page-about .about-hero__inner {
    grid-template-columns: 1.15fr 1fr;
    align-items: center;
    gap: clamp(32px, 5vw, 64px);
  }

  .page-about .about-hero__visual {
    min-height: 360px;
  }

  .page-about .about-origin__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
    align-items: start;
  }

  .page-about .about-team__inner {
    grid-template-columns: minmax(0, .88fr) minmax(0, 1.12fr);
    align-items: center;
  }

  .page-about .about-reach__inner {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    align-items: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline__ver,
  .page-about .disclosure__arrow,
  .page-about .disclosure,
  .page-about .node-map__dot,
  .page-about .node-map__tip,
  .page-about .holds__item,
  .page-about .index-item__arrow,
  .page-about .about-next__list .index-item__text {
    transition: none;
  }
}