.page-about {
  --tl-col: 62px;
  --about-line: rgba(157, 184, 217, 0.24);
  background: var(--ink);
  color: var(--fog);
  overflow-x: clip;
}

@media (min-width: 760px) {
  .page-about {
    --tl-col: 136px;
  }
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(28px, 5vw, 56px) 0 clamp(48px, 7vw, 88px);
  overflow: hidden;
}

.page-about .about-hero__beam {
  position: absolute;
  top: -18%;
  right: -22%;
  width: min(820px, 88vw);
  height: min(620px, 78vw);
  background:
    radial-gradient(circle at 62% 38%, rgba(45, 125, 255, 0.3), transparent 62%),
    radial-gradient(circle at 82% 68%, rgba(51, 224, 208, 0.14), transparent 58%);
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
}

.page-about .about-hero .eyebrow {
  margin-top: clamp(24px, 4vw, 40px);
  color: var(--mist);
}

.page-about .about-hero__title {
  margin: 12px 0 0;
  font-family: var(--font-head);
  font-size: clamp(38px, 8vw, 72px);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--snow);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 62ch;
  font-size: clamp(16px, 2vw, 18px);
  line-height: 1.85;
  color: var(--fog);
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px 16px;
  margin-top: clamp(32px, 5vw, 52px);
  padding-top: 22px;
  border-top: 1px solid var(--about-line);
}

@media (min-width: 800px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0 24px;
  }
}

.page-about .about-hero__stats .stat {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .about-hero__stats .stat__num {
  font-family: var(--font-mono);
  font-size: clamp(20px, 3vw, 28px);
  font-weight: 600;
  line-height: 1.1;
  color: var(--snow);
}

.page-about .about-hero__stats .stat__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 时间轴 ---------- */
.page-about .about-timeline {
  background:
    linear-gradient(180deg, rgba(27, 42, 68, 0.72) 0%, rgba(11, 30, 58, 0) 34%),
    var(--ink);
}

.page-about .about-timeline .eyebrow {
  color: var(--cyan);
}

.page-about .about-timeline__visual {
  margin: 0 0 clamp(40px, 6vw, 72px);
}

.page-about .about-timeline__visual .media__frame {
  border-radius: var(--radius);
  border: 1px solid var(--about-line);
  overflow: hidden;
}

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

.page-about .about-timeline__visual .media__caption {
  margin-top: 12px;
  font-size: 13px;
  color: var(--mist);
}

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

.page-about .tl__item {
  position: relative;
  display: grid;
  grid-template-columns: var(--tl-col) minmax(0, 1fr);
  align-items: start;
}

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: calc(var(--tl-col) - 1px);
  top: 34px;
  bottom: 6px;
  width: 1px;
  background: linear-gradient(180deg, var(--about-line), rgba(157, 184, 217, 0.06));
}

.page-about .tl__item:last-child::before {
  display: none;
}

.page-about .tl__mark {
  position: relative;
  padding-top: 14px;
  text-align: right;
}

.page-about .tl__mark::after {
  content: "";
  position: absolute;
  right: -5px;
  top: 20px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 0 4px rgba(45, 125, 255, 0.16);
  transition: background-color 180ms var(--ease), box-shadow 180ms var(--ease);
}

.page-about .tl__item:hover .tl__mark::after,
.page-about .tl__item:focus-within .tl__mark::after {
  background: var(--cyan);
  box-shadow: 0 0 0 6px rgba(51, 224, 208, 0.18);
}

.page-about .tl__item--now .tl__mark::after {
  background: var(--orange);
  box-shadow: 0 0 0 4px rgba(255, 138, 61, 0.18);
}

.page-about .tl__ver {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(20px, 4vw, 34px);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--snow);
}

.page-about .tl__item--now .tl__ver {
  color: var(--orange);
}

.page-about .tl__when {
  display: block;
  margin-top: 8px;
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: 0.02em;
  color: var(--mist);
}

.page-about .tl__body {
  padding: 12px 0 0 20px;
}

@media (min-width: 760px) {
  .page-about .tl__body {
    padding: 10px 0 0 34px;
  }
}

.page-about .tl__item .tl__body {
  padding-bottom: 46px;
}

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

.page-about .tl__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: clamp(19px, 2.4vw, 25px);
  font-weight: 700;
  line-height: 1.4;
  color: var(--snow);
}

.page-about .tl__text {
  margin: 0 0 14px;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--fog);
}

.page-about .tl .tick-list__item {
  font-size: 14.5px;
  color: var(--mist);
}

.page-about .about-timeline__note {
  margin: clamp(32px, 5vw, 56px) 0 0;
  padding: 18px 20px;
  border-left: 2px solid var(--blue);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: rgba(27, 42, 68, 0.7);
  font-size: 15px;
  line-height: 1.8;
  color: var(--fog);
}

/* ---------- 旧版资料归档 ---------- */
.page-about .about-archive {
  background: linear-gradient(180deg, var(--snow) 0%, #e3ecf8 100%);
  color: var(--ink);
  border-top: 1px solid var(--about-line);
}

.page-about .about-archive .eyebrow {
  color: var(--blue-dark);
}

.page-about .about-archive__title {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-size: clamp(26px, 4vw, 40px);
  font-weight: 900;
  line-height: 1.22;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.page-about .about-archive__text {
  margin: 18px 0 0;
  max-width: 66ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.page-about .steps {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

@media (min-width: 620px) {
  .page-about .steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }
}

.page-about .steps__item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  background: #ffffff;
  border: 1px solid rgba(45, 125, 255, 0.16);
  box-shadow: 0 14px 30px -24px rgba(11, 30, 58, 0.5);
}

.page-about .steps__no {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  color: var(--blue-dark);
}

.page-about .steps__label {
  font-size: 15px;
  line-height: 1.5;
  color: var(--ink);
}

.page-about .about-archive__panel {
  padding: 20px;
  border-radius: var(--radius);
  background: #ffffff;
  border: 1px solid rgba(45, 125, 255, 0.14);
  box-shadow: 0 24px 48px -34px rgba(11, 30, 58, 0.55);
}

@media (min-width: 900px) {
  .page-about .about-archive__panel {
    position: sticky;
    top: 96px;
  }
}

.page-about .about-archive__figure {
  margin: 0;
}

.page-about .about-archive__figure .media__frame {
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: var(--ink-soft);
}

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

.page-about .about-archive__figure .media__caption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist);
}

.page-about .about-archive__facts {
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: 1px solid rgba(157, 184, 217, 0.4);
}

.page-about .about-archive__fact {
  display: grid;
  gap: 4px;
  padding: 10px 0;
}

.page-about .about-archive__fact + .about-archive__fact {
  border-top: 1px dashed rgba(157, 184, 217, 0.5);
}

.page-about .about-archive__fact dt {
  font-size: 12px;
  letter-spacing: 0.04em;
  color: #6b83a8;
}

.page-about .about-archive__fact dd {
  margin: 0;
  font-size: 15px;
  line-height: 1.6;
  color: var(--ink);
}

/* ---------- 上海适配 ---------- */
.page-about .about-shanghai {
  background: var(--ink);
}

.page-about .about-shanghai .eyebrow {
  color: var(--cyan);
}

.page-about .about-shanghai__figure {
  margin: 0;
}

.page-about .about-shanghai__figure .media__frame {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--about-line);
  background: var(--ink-deep);
}

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

.page-about .about-shanghai__figure .media__caption {
  margin-top: 12px;
  font-size: 13px;
  color: var(--mist);
}

.page-about .about-shanghai__copy {
  align-self: center;
}

.page-about .about-shanghai__title {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-size: clamp(25px, 3.6vw, 38px);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: -0.02em;
  color: var(--snow);
}

.page-about .about-shanghai__text {
  margin: 18px 0 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--fog);
}

.page-about .about-shanghai__list {
  margin-top: 22px;
}

.page-about .about-shanghai__list .tick-list__item {
  font-size: 15px;
  color: var(--mist);
}

@media (min-width: 900px) {
  .page-about .about-shanghai__copy {
    padding-left: 8px;
  }
}

/* ---------- 团队与协作 ---------- */
.page-about .about-team {
  background: linear-gradient(180deg, var(--ink) 0%, var(--ink-deep) 100%);
}

.page-about .about-team .eyebrow {
  color: var(--mist);
}

.page-about .about-team__grid {
  margin-top: clamp(28px, 4vw, 44px);
}

.page-about .about-team__card {
  background: var(--slate);
  border: 1px solid var(--about-line);
  border-radius: var(--radius);
  padding: clamp(20px, 3vw, 28px);
  transition: border-color 180ms var(--ease), transform 180ms var(--ease);
}

.page-about .about-team__card:hover {
  border-color: var(--line-strong);
  transform: translateY(-3px);
}

.page-about .about-team__card .card__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.page-about .about-team__card .card__title {
  margin: 0;
  font-family: var(--font-head);
  font-size: clamp(19px, 2.4vw, 24px);
  font-weight: 700;
  color: var(--snow);
}

.page-about .about-team__card .card__text {
  margin: 14px 0 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--fog);
}

.page-about .about-team__card .tick-list {
  margin-top: 16px;
}

.page-about .about-team__card .tick-list__item {
  font-size: 14.5px;
  color: var(--mist);
}

/* ---------- 站点信息 ---------- */
.page-about .about-facts {
  background: var(--ink-deep);
  border-top: 1px solid var(--about-line);
}

.page-about .about-facts .eyebrow {
  color: var(--cyan);
}

.page-about .about-facts__copy {
  align-self: start;
}

.page-about .about-facts__title {
  margin: 10px 0 0;
  font-family: var(--font-head);
  font-size: clamp(24px, 3.4vw, 36px);
  font-weight: 900;
  line-height: 1.24;
  letter-spacing: -0.02em;
  color: var(--snow);
}

.page-about .about-facts__text {
  margin: 18px 0 0;
  max-width: 56ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--fog);
}

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

.page-about .about-facts__list {
  margin: 0;
  border-top: 1px solid var(--about-line);
}

.page-about .about-facts__row {
  display: grid;
  gap: 4px;
  padding: 14px 0;
  border-bottom: 1px solid var(--about-line);
}

@media (min-width: 720px) {
  .page-about .about-facts__row {
    grid-template-columns: 172px minmax(0, 1fr);
    gap: 0 24px;
    align-items: baseline;
  }
}

.page-about .about-facts__key {
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--mist);
}

.page-about .about-facts__val {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.65;
  color: var(--snow);
  word-break: break-word;
}

.page-about .about-facts__more {
  margin-top: clamp(32px, 5vw, 52px);
  padding: 24px;
  border-radius: var(--radius);
  background: rgba(27, 42, 68, 0.78);
  border: 1px solid var(--about-line);
  display: grid;
  gap: 18px;
}

.page-about .about-facts__more-text {
  margin: 0;
  max-width: 68ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--fog);
}

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

@media (min-width: 860px) {
  .page-about .about-facts__more {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 28px;
  }

  .page-about .about-facts__links {
    justify-content: flex-end;
  }
}

/* ---------- 窄屏收敛 ---------- */
@media (max-width: 520px) {
  .page-about .tl__body {
    padding-left: 14px;
  }

  .page-about .tl__when {
    font-size: 11px;
  }

  .page-about .about-archive__panel,
  .page-about .about-facts__more {
    padding: 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-team__card,
  .page-about .tl__mark::after {
    transition: none;
  }

  .page-about .about-team__card:hover {
    transform: none;
  }
}