.page-about {
  --about-num-font: "DIN Alternate", "Noto Sans SC", system-ui, sans-serif;
  background: var(--c-space);
  color: var(--text);
  font-family: var(--font-sans);
  overflow-x: hidden;
}

.page-about .about-crumbs {
  margin-bottom: 28px;
}

.page-about .about-crumbs .crumbs-link {
  color: var(--text-mute);
  font-size: 13px;
  text-decoration: none;
  transition: color .25s var(--ease);
}

.page-about .about-crumbs .crumbs-link:hover {
  color: var(--c-amber);
}

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

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding-top: 32px;
  padding-bottom: 56px;
  background:
    radial-gradient(760px 420px at 82% -10%, rgba(123, 44, 255, .30), transparent 70%),
    radial-gradient(620px 380px at 6% 22%, rgba(255, 107, 26, .16), transparent 72%);
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.page-about .about-hero-rail {
  display: flex;
  align-items: center;
  gap: 16px;
}

.page-about .about-big-num {
  display: block;
  font-family: var(--about-num-font);
  font-weight: 900;
  font-size: clamp(3.4rem, 12vw, 8rem);
  line-height: .82;
  letter-spacing: -.05em;
  background: linear-gradient(158deg, var(--c-purple-soft) 8%, var(--c-orange) 78%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.page-about .about-rail-note {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .22em;
  color: var(--c-mist);
  white-space: nowrap;
}

.page-about .about-title {
  margin: 10px 0 18px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2rem, 6.4vw, 4rem);
  line-height: 1.12;
  letter-spacing: -.02em;
  color: var(--c-ice);
}

.page-about .about-lead {
  max-width: 44ch;
  color: var(--text-soft);
  font-size: 16px;
  line-height: 1.85;
}

.page-about .about-facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-facts li {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 14px 16px;
  background: var(--c-midnight);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  border-left: 3px solid var(--c-purple);
  transition: border-left-color .25s var(--ease), transform .25s var(--ease);
}

.page-about .about-facts li:hover {
  border-left-color: var(--c-orange);
  transform: translateY(-2px);
}

.page-about .about-facts strong {
  font-family: var(--about-num-font);
  font-size: 26px;
  font-weight: 900;
  color: var(--c-ice);
  letter-spacing: -.02em;
}

.page-about .about-facts span {
  font-size: 12.5px;
  color: var(--text-mute);
}

.page-about .about-hero-figure {
  margin: 0;
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line-strong);
  background: linear-gradient(150deg, rgba(123, 44, 255, .28), rgba(255, 107, 26, .12));
  object-fit: cover;
}

.page-about .about-hero-figure .annotation {
  display: block;
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--c-mist);
}

/* ---------- 章节公共头 ---------- */
.page-about .about-sec-head {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-bottom: 34px;
}

.page-about .about-sec-head--tight {
  margin-bottom: 26px;
}

.page-about .about-sec-num {
  font-family: var(--about-num-font);
  font-weight: 900;
  font-size: clamp(2.4rem, 8vw, 4.4rem);
  line-height: .9;
  letter-spacing: -.05em;
  color: transparent;
  -webkit-text-stroke: 1.5px rgba(177, 92, 255, .55);
}

.page-about .about-h2 {
  margin: 8px 0 12px;
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.5rem, 4.4vw, 2.5rem);
  line-height: 1.22;
  letter-spacing: -.01em;
  color: var(--c-ice);
}

.page-about .about-sec-lead {
  max-width: 52ch;
  color: var(--text-soft);
  font-size: 15.5px;
  line-height: 1.85;
}

/* ---------- 成长路线 ---------- */
.page-about .about-roadmap {
  position: relative;
  overflow: hidden;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(20, 27, 61, .92), rgba(11, 16, 38, .96));
}

.page-about .about-roadmap-texture {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .14;
  pointer-events: none;
}

.page-about .about-roadmap .container {
  position: relative;
  z-index: 1;
}

.page-about .about-timeline {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 20px;
  width: 2px;
  background: linear-gradient(180deg, var(--c-purple), var(--c-orange) 55%, rgba(95, 242, 194, .5));
  border-radius: var(--radius-pill);
}

.page-about .about-stage {
  position: relative;
  margin-left: 48px;
  padding: 20px 20px 18px;
  background: var(--c-midnight);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: border-color .28s var(--ease), transform .28s var(--ease);
}

.page-about .about-stage::before {
  content: "";
  position: absolute;
  top: 26px;
  left: -35px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--c-space);
  border: 2px solid var(--c-purple-soft);
  transition: background .28s var(--ease), border-color .28s var(--ease), box-shadow .28s var(--ease);
}

.page-about .about-stage:hover,
.page-about .about-stage:focus-within {
  border-color: var(--line-strong);
  transform: translateY(-2px);
}

.page-about .about-stage:hover::before,
.page-about .about-stage:focus-within::before {
  background: var(--c-orange);
  border-color: var(--c-orange);
  box-shadow: 0 0 0 5px rgba(255, 107, 26, .18);
}

.page-about .about-stage-num {
  display: inline-block;
  margin-bottom: 8px;
  padding: 2px 9px;
  font-family: var(--about-num-font);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--c-amber);
  border: 1px solid rgba(255, 178, 62, .38);
  border-radius: var(--radius-pill);
}

.page-about .about-stage h3 {
  margin: 0 0 8px;
  font-size: 18px;
  font-weight: 900;
  color: var(--c-ice);
  letter-spacing: .01em;
}

.page-about .about-stage p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-soft);
}

.page-about .about-stage .about-stage-more {
  margin-top: 10px;
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--c-mist);
  opacity: .7;
  transition: opacity .28s var(--ease), color .28s var(--ease);
}

.page-about .about-stage:hover .about-stage-more,
.page-about .about-stage:focus-within .about-stage-more {
  opacity: 1;
  color: var(--c-mint);
}

/* ---------- 内容工序 ---------- */
.page-about .about-craft-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  align-items: start;
}

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

.page-about .about-crew {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 14px;
  padding: 18px;
  background: var(--c-ice);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(123, 44, 255, .22);
  transition: transform .28s var(--ease), box-shadow .28s var(--ease);
}

.page-about .about-crew:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

.page-about .about-crew-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  font-family: var(--about-num-font);
  font-size: 17px;
  font-weight: 900;
  color: var(--c-ice);
  background: linear-gradient(150deg, var(--c-purple), var(--c-purple-soft));
}

.page-about .about-crew-badge--orange {
  background: linear-gradient(150deg, var(--c-orange), var(--c-amber));
  color: var(--c-carbon);
}

.page-about .about-crew-badge--mint {
  background: linear-gradient(150deg, #2bbd92, var(--c-mint));
  color: var(--c-carbon);
}

.page-about .about-crew h3 {
  margin: 2px 0 6px;
  font-size: 17px;
  font-weight: 900;
  color: #1b1630;
}

.page-about .about-crew p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: #4a4560;
}

.page-about .about-craft-figure {
  margin: 0;
}

.page-about .about-craft-figure img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--line-strong);
  background: linear-gradient(160deg, rgba(123, 44, 255, .24), rgba(95, 242, 194, .10));
  object-fit: cover;
}

.page-about .about-craft-figure .annotation {
  display: block;
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--c-mist);
}

/* ---------- 服务覆盖 ---------- */
.page-about .about-reach {
  background: linear-gradient(180deg, transparent, rgba(123, 44, 255, .08) 40%, transparent);
}

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

.page-about .about-stat {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-height: 132px;
  padding: 16px 14px;
  background: var(--c-midnight);
  border: 1px solid var(--line);
  border-top: 2px solid rgba(177, 92, 255, .55);
  border-radius: var(--radius);
  transition: border-top-color .28s var(--ease), background .28s var(--ease);
}

.page-about .about-stat:hover {
  border-top-color: var(--c-orange);
  background: #18204a;
}

.page-about .about-stat-num {
  font-family: var(--about-num-font);
  font-size: clamp(1.9rem, 6vw, 2.6rem);
  font-weight: 900;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--c-ice);
}

.page-about .about-stat-unit {
  font-size: .55em;
  margin-left: 2px;
  color: var(--c-amber);
}

.page-about .about-stat-name {
  font-size: 13px;
  font-weight: 700;
  color: var(--c-purple-soft);
  letter-spacing: .04em;
}

.page-about .about-stat-hint {
  margin-top: auto;
  font-size: 12px;
  line-height: 1.65;
  color: var(--text-mute);
  transition: color .28s var(--ease);
}

.page-about .about-stat:hover .about-stat-hint {
  color: var(--c-mint);
}

.page-about .about-scenes {
  margin-top: 34px;
  padding: 22px 20px;
  background: rgba(20, 27, 61, .7);
  border: 1px solid var(--line);
  border-left: 3px solid var(--c-orange);
  border-radius: var(--radius-lg);
}

.page-about .about-scenes-title {
  margin: 0 0 16px;
  font-size: 17px;
  font-weight: 900;
  color: var(--c-ice);
}

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

.page-about .about-scene-list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--text-soft);
}

.page-about .about-scenes-more {
  margin: 18px 0 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-mute);
}

.page-about .about-scenes-more a,
.page-about .about-side-foot a {
  color: var(--c-amber);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 178, 62, .4);
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .about-scenes-more a:hover,
.page-about .about-side-foot a:hover {
  color: var(--c-mint);
  border-color: var(--c-mint);
}

/* ---------- 合作生态 ---------- */
.page-about .about-eco-list {
  display: grid;
  gap: 12px;
}

.page-about .about-eco-item {
  background: var(--c-midnight);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: border-color .28s var(--ease);
}

.page-about .about-eco-item[open] {
  border-color: var(--line-strong);
  background: linear-gradient(140deg, rgba(123, 44, 255, .18), rgba(20, 27, 61, .95) 60%);
}

.page-about .about-eco-item summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}

.page-about .about-eco-item summary::-webkit-details-marker {
  display: none;
}

.page-about .about-eco-index {
  font-family: var(--about-num-font);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--c-mist);
}

.page-about .about-eco-name {
  font-size: 17px;
  font-weight: 900;
  color: var(--c-ice);
}

.page-about .about-eco-mark {
  position: relative;
  margin-left: auto;
  width: 16px;
  height: 16px;
  flex: 0 0 auto;
}

.page-about .about-eco-mark::before,
.page-about .about-eco-mark::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 0;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: var(--c-orange);
  transition: transform .28s var(--ease);
}

.page-about .about-eco-mark::after {
  transform: rotate(90deg);
}

.page-about .about-eco-item[open] .about-eco-mark::after {
  transform: rotate(0deg);
}

.page-about .about-eco-item p {
  margin: 0;
  padding: 0 18px 18px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-soft);
}

/* ---------- 长期维护 ---------- */
.page-about .about-keep {
  border-top: 1px solid var(--line);
  background:
    radial-gradient(600px 320px at 88% 100%, rgba(255, 107, 26, .16), transparent 70%),
    linear-gradient(180deg, rgba(11, 16, 38, .2), rgba(5, 6, 13, .7));
}

.page-about .about-keep-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 34px;
  align-items: start;
}

.page-about .about-keep-list {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-keep-list li {
  display: grid;
  grid-template-columns: 46px minmax(0, 1fr);
  gap: 14px;
  padding: 16px 0;
  border-top: 1px dashed var(--line);
}

.page-about .about-keep-num {
  font-family: var(--about-num-font);
  font-size: 20px;
  font-weight: 900;
  letter-spacing: -.02em;
  color: var(--c-purple-soft);
}

.page-about .about-keep-list h3 {
  margin: 0 0 6px;
  font-size: 16.5px;
  font-weight: 900;
  color: var(--c-ice);
}

.page-about .about-keep-list p {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--text-soft);
}

.page-about .about-keep-side {
  padding: 24px 20px;
  background: var(--c-ice);
  border-radius: var(--radius-lg);
  border-bottom: 4px solid var(--c-orange);
}

.page-about .about-side-note {
  margin: 0;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: #6b6488;
}

.page-about .about-side-title {
  margin: 10px 0 10px;
  font-size: 20px;
  font-weight: 900;
  line-height: 1.35;
  color: #1b1630;
}

.page-about .about-side-text {
  margin: 0 0 18px;
  font-size: 14px;
  line-height: 1.85;
  color: #4a4560;
}

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-side-foot {
  margin: 16px 0 0;
  font-size: 13px;
  line-height: 1.8;
  color: #4a4560;
}

.page-about .about-side-foot a {
  color: #6a28c9;
  border-color: rgba(106, 40, 201, .35);
}

.page-about .about-side-foot a:hover {
  color: var(--c-orange);
  border-color: var(--c-orange);
}

/* ---------- 桌面 ---------- */
@media (min-width: 900px) {
  .page-about .about-hero {
    padding-top: 48px;
    padding-bottom: 84px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: 96px minmax(0, 1fr) minmax(0, 380px);
    gap: 44px;
    align-items: start;
  }

  .page-about .about-hero-rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
    padding-top: 6px;
  }

  .page-about .about-rail-note {
    writing-mode: vertical-rl;
    letter-spacing: .30em;
    font-size: 11.5px;
  }

  .page-about .about-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-top: 34px;
  }

  .page-about .about-hero-figure {
    margin-top: 34px;
  }

  .page-about .about-sec-head {
    grid-template-columns: 118px minmax(0, 1fr);
    gap: 26px;
    align-items: start;
    margin-bottom: 48px;
  }

  .page-about .about-sec-head--tight {
    margin-bottom: 30px;
  }

  .page-about .about-sec-num {
    font-size: 4.6rem;
    padding-top: 4px;
  }

  .page-about .about-timeline {
    grid-template-columns: 1fr 1fr;
    column-gap: 84px;
    row-gap: 8px;
  }

  .page-about .about-timeline::before {
    left: 50%;
    top: 10px;
    bottom: 10px;
    transform: translateX(-1px);
  }

  .page-about .about-stage {
    margin-left: 0;
    padding: 24px 24px 20px;
  }

  .page-about .about-stage:nth-child(odd) {
    grid-column: 1;
  }

  .page-about .about-stage:nth-child(even) {
    grid-column: 2;
    margin-top: 72px;
  }

  .page-about .about-stage::before {
    left: -49px;
    top: 32px;
  }

  .page-about .about-stage:nth-child(odd)::before {
    left: auto;
    right: -49px;
  }

  .page-about .about-stage h3 {
    font-size: 20px;
  }

  .page-about .about-craft-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    gap: 48px;
  }

  .page-about .about-craft-figure {
    position: sticky;
    top: 120px;
  }

  .page-about .about-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
  }

  .page-about .about-stat:nth-child(even) {
    margin-top: 22px;
  }

  .page-about .about-scenes {
    padding: 30px 32px;
  }

  .page-about .about-scene-list {
    grid-template-columns: 1fr 1fr;
    gap: 14px 28px;
  }

  .page-about .about-eco-list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;
    align-items: start;
  }

  .page-about .about-eco-item:nth-child(2) {
    margin-top: 28px;
  }

  .page-about .about-keep-grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, .7fr);
    gap: 52px;
  }

  .page-about .about-keep-side {
    position: sticky;
    top: 120px;
  }
}

@media (min-width: 1180px) {
  .page-about .about-hero-grid {
    grid-template-columns: 110px minmax(0, 1fr) minmax(0, 420px);
    gap: 56px;
  }

  .page-about .about-stage {
    padding: 26px 26px 22px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-facts li,
  .page-about .about-stage,
  .page-about .about-crew,
  .page-about .about-stat,
  .page-about .about-stage::before,
  .page-about .about-eco-mark::before,
  .page-about .about-eco-mark::after {
    transition: none;
  }
}