.page-about {
  --about-cut: 14px;
  --about-line: rgba(143, 163, 184, .26);
  --about-line-strong: rgba(143, 163, 184, .5);
  --about-card: linear-gradient(152deg, rgba(19, 41, 61, .96), rgba(11, 27, 43, .97));
  display: block;
  overflow-x: hidden;
  color: var(--paper);
  font-family: var(--font-body);
  background:
    radial-gradient(1100px 460px at 84% -8%, rgba(215, 38, 61, .2), transparent 64%),
    radial-gradient(820px 420px at -8% 16%, rgba(24, 224, 216, .09), transparent 62%),
    var(--ink);
}

.page-about a:focus-visible,
.page-about [tabindex]:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- 面包屑 ---------- */
.page-about .crumbs ol {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 18px 0 0;
  list-style: none;
  font-size: 13px;
  color: var(--steel);
}

.page-about .crumbs li + li::before {
  content: "/";
  margin-right: 6px;
  color: rgba(143, 163, 184, .55);
}

.page-about .crumbs a {
  color: var(--steel);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color .2s ease, border-color .2s ease;
}

.page-about .crumbs a:hover {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.page-about .crumbs [aria-current="page"] {
  color: var(--paper);
}

/* ---------- 首屏 ---------- */
.page-about .about-open {
  position: relative;
  padding-bottom: 44px;
}

.page-about .about-open__inner {
  display: grid;
  gap: 30px;
  margin-top: 24px;
}

.page-about .about-open__copy h1 {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-size: clamp(30px, 7vw, 52px);
  line-height: 1.08;
  letter-spacing: -.02em;
  text-transform: none;
  color: var(--paper);
}

.page-about .about-open__copy .lead {
  margin: 0;
  max-width: 60ch;
}

.page-about .about-open__stats {
  display: flex;
  flex-wrap: wrap;
  gap: 16px 28px;
  margin-top: 26px;
  padding-top: 20px;
  border-top: 1px solid var(--about-line);
}

.page-about .about-open__stat {
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-width: 92px;
}

.page-about .about-open__stat .num {
  font-family: var(--font-num);
  font-size: 26px;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--gold);
}

.page-about .about-open__stat-label {
  font-size: 13px;
  color: var(--steel);
}

.page-about .about-open__visual {
  position: relative;
  margin: 0;
  background: var(--board);
  border: 1px solid var(--about-line);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 26px), calc(100% - 26px) 100%, 0 100%);
}

.page-about .about-open__visual::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--red), var(--gold));
  z-index: 2;
}

.page-about .about-open__visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
  filter: saturate(.94) contrast(1.04);
}

.page-about .about-open__visual figcaption {
  padding: 10px 16px 14px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--steel);
  border-top: 1px solid var(--about-line);
}

/* ---------- 起点与定位 ---------- */
.page-about .about-origin {
  padding: 46px 0 40px;
  background: linear-gradient(180deg, rgba(19, 41, 61, .58), rgba(11, 27, 43, 0) 88%);
}

.page-about .about-origin__head h2 {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-origin__cols {
  display: grid;
  gap: 18px;
  margin-top: 22px;
}

.page-about .about-origin__cols p {
  margin: 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink-soft);
}

.page-about .about-origin__notes {
  display: grid;
  gap: 14px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-origin__notes li {
  position: relative;
  padding: 14px 16px 14px 20px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
  background: rgba(19, 41, 61, .62);
  border: 1px solid var(--about-line);
  border-left: 3px solid var(--red);
}

.page-about .about-origin__notes strong {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-display);
  font-size: 16px;
  letter-spacing: .01em;
  color: var(--gold);
}

/* ---------- 版本里程碑 ---------- */
.page-about .about-versions {
  padding: 48px 0 52px;
}

.page-about .about-versions .section__head h2 {
  margin: 8px 0 12px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-versions__figure {
  position: relative;
  margin: 26px 0 34px;
  border: 1px solid var(--about-line);
  background: var(--board);
  clip-path: polygon(var(--about-cut) 0, 100% 0, 100% 100%, 0 100%, 0 var(--about-cut));
}

.page-about .about-versions__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .about-versions__figure figcaption {
  padding: 10px 16px 14px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--steel);
  border-top: 1px solid var(--about-line);
}

.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 30px;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--red), var(--gold) 48%, var(--cyan) 100%);
}

.page-about .timeline__item {
  position: relative;
  margin-bottom: 22px;
}

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

.page-about .timeline__dot {
  position: absolute;
  top: 22px;
  left: -26px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink);
  border: 2px solid var(--gold);
  box-shadow: 0 0 0 4px rgba(242, 183, 5, .16);
  z-index: 1;
}

.page-about .timeline__card {
  padding: 18px 20px 20px;
  background: var(--about-card);
  border: 1px solid var(--about-line);
  border-left: 3px solid var(--gold);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-cut)), calc(100% - var(--about-cut)) 100%, 0 100%);
  transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}

.page-about .timeline__card:hover,
.page-about .timeline__card:focus-visible {
  transform: translateY(-3px);
  border-color: rgba(242, 183, 5, .68);
  box-shadow: 0 16px 34px rgba(0, 0, 0, .36);
}

.page-about .timeline__ver {
  margin: 0 0 6px;
  font-family: var(--font-num);
  font-size: 20px;
  letter-spacing: .04em;
  color: var(--gold);
}

.page-about .timeline__card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-size: 19px;
  line-height: 1.3;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .timeline__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--ink-soft);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: 48px 0 50px;
  background:
    linear-gradient(160deg, rgba(19, 41, 61, .9), rgba(11, 27, 43, .96) 70%),
    var(--ink);
  border-top: 1px solid var(--about-line);
  border-bottom: 1px solid var(--about-line);
}

.page-about .about-team__head h2 {
  margin: 8px 0 12px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-team__body {
  display: grid;
  gap: 26px;
  margin-top: 28px;
}

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

.page-about .team-card {
  padding: 18px 18px 20px;
  background: rgba(11, 27, 43, .72);
  border: 1px solid var(--about-line);
  clip-path: polygon(0 0, calc(100% - var(--about-cut)) 0, 100% var(--about-cut), 100% 100%, 0 100%);
  transition: border-color .25s ease, transform .25s ease;
}

.page-about .team-card:hover {
  transform: translateY(-3px);
  border-color: rgba(24, 224, 216, .5);
}

.page-about .team-card .num {
  display: block;
  font-family: var(--font-num);
  font-size: 40px;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--gold);
}

.page-about .team-card h3 {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  letter-spacing: .01em;
  color: var(--paper);
}

.page-about .team-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .about-team__figure {
  margin: 0;
  border: 1px solid var(--about-line);
  background: var(--board);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 24px), calc(100% - 24px) 100%, 0 100%);
}

.page-about .about-team__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 10 / 7;
  object-fit: cover;
}

.page-about .about-team__figure figcaption {
  padding: 10px 16px 14px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--steel);
  border-top: 1px solid var(--about-line);
}

/* ---------- 覆盖与生态 ---------- */
.page-about .about-reach {
  padding: 48px 0 50px;
}

.page-about .about-reach__top {
  display: grid;
  gap: 28px;
}

.page-about .about-reach__copy h2 {
  margin: 8px 0 14px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-reach__copy p {
  margin: 0 0 12px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink-soft);
}

.page-about .about-reach__copy p:last-child {
  margin-bottom: 0;
}

.page-about .about-reach__gauge-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 22px 18px;
  background: rgba(19, 41, 61, .6);
  border: 1px solid var(--about-line);
  border-top: 3px solid var(--red);
}

.page-about .about-reach__gauge {
  width: 168px;
  height: 168px;
  max-width: 100%;
}

.page-about .about-reach__gauge-num {
  font-family: var(--font-num);
  font-size: 34px;
  fill: var(--gold);
}

.page-about .about-reach__gauge-cap {
  font-size: 12px;
  letter-spacing: .06em;
  fill: var(--steel);
}

.page-about .about-reach__gauge-note {
  margin: 0;
  font-size: 13px;
  line-height: 1.6;
  text-align: center;
  color: var(--steel);
}

.page-about .about-reach__tiles {
  display: grid;
  gap: 12px;
  margin-top: 28px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.page-about .about-reach__tiles .tile {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 14px 16px;
  background: rgba(11, 27, 43, .78);
  border: 1px solid var(--about-line);
  border-bottom: 3px solid var(--gold);
}

.page-about .about-reach__tiles .tile__label {
  font-size: 12px;
  line-height: 1.5;
  color: var(--steel);
}

.page-about .about-reach__tiles .tile__value {
  font-family: var(--font-num);
  font-size: 22px;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--paper);
}

/* ---------- 荣誉 ---------- */
.page-about .about-honor {
  padding: 48px 0 50px;
  background: linear-gradient(140deg, rgba(215, 38, 61, .24), rgba(11, 27, 43, .94) 66%);
  border-top: 1px solid rgba(215, 38, 61, .38);
  border-bottom: 1px solid rgba(215, 38, 61, .38);
}

.page-about .about-honor .section__head h2 {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .chip--gold {
  display: inline-block;
  align-self: flex-start;
  background: rgba(242, 183, 5, .14);
  border-color: rgba(242, 183, 5, .55);
  color: var(--gold);
}

.page-about .honor-grid {
  display: grid;
  gap: 16px;
  margin-top: 26px;
}

.page-about .honor-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 20px 20px 22px;
  background: rgba(11, 27, 43, .82);
  border: 1px solid var(--about-line);
  border-top: 4px solid var(--gold);
  clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
}

.page-about .honor-card h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 21px;
  letter-spacing: -.01em;
  color: var(--paper);
}

.page-about .honor-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.74;
  color: var(--ink-soft);
}

.page-about .honor-metrics {
  display: grid;
  gap: 14px;
  margin-top: 26px;
  padding-top: 24px;
  border-top: 1px solid rgba(242, 183, 5, .3);
}

.page-about .honor-metric {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about .honor-metric .num {
  font-family: var(--font-num);
  font-size: 30px;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--gold);
}

.page-about .honor-metric__label {
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-soft);
}

/* ---------- 下一步 ---------- */
.page-about .about-next {
  padding: 48px 0 50px;
  background: linear-gradient(180deg, rgba(19, 41, 61, .92), rgba(11, 27, 43, .98));
}

.page-about .about-next__inner {
  display: grid;
  gap: 26px;
}

.page-about .about-next__copy h2 {
  margin: 8px 0 14px;
  font-family: var(--font-display);
  font-size: clamp(24px, 5vw, 36px);
  line-height: 1.18;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-next__copy p {
  margin: 0 0 12px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--ink-soft);
}

.page-about .about-next__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-next__side {
  padding: 20px 20px 22px;
  background: rgba(11, 27, 43, .74);
  border: 1px solid var(--about-line);
  border-left: 4px solid var(--cyan);
}

.page-about .about-next__side-title {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: 16px;
  letter-spacing: .04em;
  color: var(--cyan);
}

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

.page-about .about-next__list li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .about-next__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 8px;
  height: 8px;
  background: var(--gold);
  transform: rotate(45deg);
}

/* ---------- 联系 ---------- */
.page-about .about-contact {
  padding: 42px 0 56px;
  background: linear-gradient(120deg, rgba(215, 38, 61, .92), rgba(183, 30, 51, .96));
}

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

.page-about .about-contact__copy .kicker {
  color: rgba(247, 241, 230, .82);
}

.page-about .about-contact__copy h2 {
  margin: 8px 0 12px;
  font-family: var(--font-display);
  font-size: clamp(23px, 5vw, 34px);
  line-height: 1.2;
  letter-spacing: -.02em;
  color: var(--paper);
}

.page-about .about-contact__copy p {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: rgba(247, 241, 230, .9);
}

.page-about .about-contact__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-origin__notes {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

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

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

  .page-about .about-contact__links {
    align-items: center;
  }
}

@media (min-width: 860px) {
  .page-about .about-open__inner {
    grid-template-columns: 1.06fr .94fr;
    gap: 46px;
    align-items: start;
    margin-top: 30px;
  }

  .page-about .about-open__visual {
    margin-top: 26px;
  }

  .page-about .about-origin__cols {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 30px;
  }

  .page-about .about-team__body {
    grid-template-columns: 1.15fr .85fr;
    gap: 30px;
    align-items: start;
  }

  .page-about .about-team__figure {
    margin-top: 14px;
  }

  .page-about .about-reach__top {
    grid-template-columns: 1.5fr .9fr;
    gap: 38px;
    align-items: start;
  }

  .page-about .about-next__inner {
    grid-template-columns: 1.35fr .85fr;
    gap: 38px;
    align-items: start;
  }

  .page-about .about-contact__inner {
    grid-template-columns: 1.4fr auto;
    gap: 34px;
    align-items: center;
  }

  .page-about .about-contact__links {
    flex-direction: column;
    align-items: stretch;
    min-width: 250px;
  }
}

@media (min-width: 980px) {
  .page-about .timeline {
    padding-left: 0;
  }

  .page-about .timeline::before {
    left: 50%;
    margin-left: -1px;
  }

  .page-about .timeline__item {
    width: calc(50% - 46px);
    margin-bottom: 30px;
  }

  .page-about .timeline__item:nth-child(even) {
    margin-left: auto;
  }

  .page-about .timeline__item:nth-child(odd) {
    text-align: right;
  }

  .page-about .timeline__item:nth-child(odd) .timeline__card {
    border-left: 1px solid var(--about-line);
    border-right: 3px solid var(--gold);
    clip-path: polygon(0 0, 100% 0, 100% 100%, var(--about-cut) 100%, 0 calc(100% - var(--about-cut)));
  }

  .page-about .timeline__item:nth-child(odd) .timeline__dot {
    left: auto;
    right: -52px;
  }

  .page-about .timeline__item:nth-child(even) .timeline__dot {
    left: -52px;
  }

  .page-about .team-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .timeline__card,
  .page-about .team-card {
    transition: none;
  }

  .page-about .timeline__card:hover,
  .page-about .timeline__card:focus-visible,
  .page-about .team-card:hover {
    transform: none;
  }
}