.page-about {
  --about-line: rgba(15, 110, 140, 0.16);
  --about-axis: rgba(15, 110, 140, 0.3);
}

.page-about img {
  max-width: 100%;
  height: auto;
}

.page-about .about-crumb {
  margin: 0 0 24px;
}

/* ================= 首屏 ================= */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: calc(var(--header-h) + 26px) 0 54px;
  background:
    radial-gradient(120% 100% at 6% -12%, rgba(15, 110, 140, 0.22), transparent 60%),
    radial-gradient(95% 80% at 94% 2%, rgba(224, 122, 63, 0.2), transparent 62%),
    linear-gradient(180deg, var(--mist) 0%, rgba(252, 253, 253, 0.92) 70%, var(--snow) 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--line-strong), transparent);
}

.page-about .about-hero-grid {
  display: grid;
  gap: 34px;
}

.page-about .about-hero h1 {
  margin: 14px 0 0;
  font-size: clamp(2rem, 6.4vw, 3.5rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  font-weight: 800;
  color: var(--lake-deep);
}

.page-about .about-hero .lede {
  margin: 18px 0 0;
  max-width: 34em;
  color: var(--ink);
  font-size: 16.5px;
  line-height: 1.85;
}

.page-about .hero-facts {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 9px 10px;
}

.page-about .hero-facts li {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  color: var(--lake-deep);
  background: rgba(252, 253, 253, 0.72);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 13px;
}

.page-about .hero-figure {
  margin: 0;
  padding: 9px;
  border-radius: calc(var(--radius-l) + 8px);
  background: var(--glass);
  border: 1px solid var(--line);
  backdrop-filter: blur(6px);
  box-shadow: var(--shadow-lift);
}

.page-about .hero-figure img {
  display: block;
  width: 100%;
  border-radius: var(--radius-l);
}

.page-about .hero-figure figcaption {
  margin: 10px 4px 2px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.05em;
  color: var(--slate);
}

/* ================= 标识轻挂 ================= */
.page-about .mark-grid {
  display: grid;
  gap: 34px;
}

.page-about .mark-copy p {
  margin: 16px 0 0;
  color: var(--ink);
  line-height: 1.85;
}

.page-about .mark-points {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.page-about .mark-points li {
  position: relative;
  padding-left: 26px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.page-about .mark-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 14px;
  height: 2px;
  background: var(--sand);
}

.page-about .mark-stage {
  position: relative;
  min-height: 300px;
  border-radius: var(--radius-l);
  border: 1px solid var(--line);
  background:
    repeating-linear-gradient(180deg, rgba(15, 110, 140, 0.07) 0 1px, transparent 1px 26px),
    linear-gradient(160deg, rgba(232, 241, 244, 0.92), rgba(252, 253, 253, 0.94));
  display: grid;
  place-items: center;
  overflow: hidden;
  box-shadow: var(--shadow-soft);
}

.page-about .mark-hanger {
  position: absolute;
  top: 0;
  left: 50%;
  width: 1px;
  height: calc(50% - 60px);
  background: linear-gradient(180deg, rgba(224, 122, 63, 0), var(--sand));
}

.page-about .mark-disc {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--lake-deep);
  background: radial-gradient(circle at 34% 28%, #ffffff, var(--mist) 58%, #c4dde7);
  border: 1px solid rgba(15, 110, 140, 0.3);
  box-shadow: var(--shadow-lift);
  animation: about-float 6s ease-in-out infinite;
}

.page-about .mark-label {
  position: absolute;
  bottom: 22px;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--slate);
  white-space: nowrap;
}

@keyframes about-float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

/* ================= 年份时间轴 ================= */
.page-about .tl-head .lede {
  margin: 14px 0 0;
  max-width: 40em;
  color: var(--ink);
}

.page-about .year-jump {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 22px;
}

.page-about .year-jump a {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  text-decoration: none;
  color: var(--lake-deep);
  background: var(--snow);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 13px;
  transition: border-color 200ms var(--ease), color 200ms var(--ease), background 200ms var(--ease);
}

.page-about .year-jump a:hover,
.page-about .year-jump a:focus-visible {
  border-color: var(--sand);
  color: var(--sand-deep);
  background: var(--sand-mist);
}

.page-about .timeline {
  position: relative;
  list-style: none;
  margin: 40px 0 0;
  padding: 0;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--lake), rgba(224, 122, 63, 0.75));
  opacity: 0.4;
}

.page-about .tl-item {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  padding-left: 40px;
  margin-bottom: 40px;
}

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

.page-about .tl-marker {
  position: relative;
  order: -1;
}

.page-about .tl-marker::before {
  content: "";
  position: absolute;
  left: -40px;
  top: 2px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--snow);
  border: 2px solid var(--sand);
  box-sizing: border-box;
}

.page-about .tl-year {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--sand-deep);
}

.page-about .tl-content {
  background: var(--snow);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  padding: 20px 20px 22px;
  box-shadow: var(--shadow-soft);
}

.page-about .tl-content h3 {
  margin: 0;
  font-size: 1.12rem;
  line-height: 1.5;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--lake-deep);
}

.page-about .tl-content p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .tl-tags {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .tl-note {
  margin: 0;
  padding-left: 14px;
  border-left: 2px solid var(--mist);
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--slate);
}

/* ================= 团队 ================= */
.page-about .team-head .lede {
  margin: 14px 0 0;
  max-width: 42em;
  color: var(--ink);
}

.page-about .team-grid {
  display: grid;
  gap: 16px;
  margin-top: 34px;
}

.page-about .team-cell {
  position: relative;
  background: var(--snow);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  padding: 22px 20px;
  overflow: hidden;
  transition: transform 260ms var(--ease), box-shadow 260ms var(--ease);
}

.page-about .team-cell:hover,
.page-about .team-cell:focus-within {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lift);
}

.page-about .team-cell:nth-child(1) { border-top: 3px solid var(--lake); }
.page-about .team-cell:nth-child(2) { border-top: 3px solid var(--sand); }
.page-about .team-cell:nth-child(3) { border-top: 3px solid var(--lake-deep); }
.page-about .team-cell:nth-child(4) { border-top: 3px solid var(--ok); }

.page-about .team-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--lake);
}

.page-about .team-name {
  margin: 12px 0 0;
  font-size: 1.02rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.page-about .team-key {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.06em;
  color: var(--slate);
}

.page-about .team-more {
  display: block;
  margin: 12px 0 0;
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--slate);
}

.page-about .team-figure {
  margin: 34px 0 0;
  padding: 9px;
  border-radius: calc(var(--radius-l) + 8px);
  background: linear-gradient(150deg, rgba(216, 233, 239, 0.7), rgba(247, 231, 216, 0.6));
  border: 1px solid var(--line);
}

.page-about .team-figure img {
  display: block;
  width: 100%;
  border-radius: var(--radius-l);
}

.page-about .team-figure figcaption {
  margin: 10px 4px 2px;
  font-size: 13px;
  color: var(--slate);
}

/* ================= 覆盖规模 ================= */
.page-about .about-scale {
  position: relative;
  overflow: hidden;
  background: linear-gradient(180deg, var(--snow), var(--mist));
}

.page-about .scale-contour {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.2;
  pointer-events: none;
}

.page-about .scale-inner {
  position: relative;
  z-index: 1;
}

.page-about .scale-head .lede {
  margin: 14px 0 0;
  max-width: 40em;
  color: var(--ink);
}

.page-about .stat-band {
  list-style: none;
  margin: 34px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  overflow: hidden;
}

.page-about .stat-band li {
  background: rgba(252, 253, 253, 0.88);
  padding: 20px 18px;
}

.page-about .stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 5vw, 2.2rem);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--lake);
}

.page-about .stat-unit {
  font-size: 0.52em;
  margin-left: 3px;
  color: var(--lake-deep);
}

.page-about .stat-label {
  display: block;
  margin-top: 6px;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--slate);
}

.page-about .scale-note {
  margin: 24px 0 0;
  padding: 16px 18px;
  border-radius: var(--radius-s);
  background: rgba(252, 253, 253, 0.82);
  border-left: 3px solid var(--sand);
  font-size: 14.5px;
  line-height: 1.8;
  color: var(--ink);
}

/* ================= 兼容性生态 ================= */
.page-about .eco-grid {
  display: grid;
  gap: 32px;
}

.page-about .eco-copy p {
  margin: 16px 0 0;
  color: var(--ink);
  line-height: 1.85;
}

.page-about .eco-link {
  margin-top: 20px;
}

.page-about .eco-link a {
  font-weight: 600;
  color: var(--sand-deep);
  text-decoration: none;
  border-bottom: 1px solid rgba(168, 73, 28, 0.4);
  padding-bottom: 2px;
}

.page-about .eco-link a:hover {
  color: var(--lake);
  border-bottom-color: var(--lake);
}

.page-about .spec-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
  align-content: start;
}

.page-about .spec {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  align-items: center;
  padding: 16px 18px;
  background: var(--snow);
  border: 1px solid var(--line);
  border-left: 3px solid var(--lake);
  border-radius: var(--radius-s);
  box-shadow: var(--shadow-soft);
}

.page-about .spec:nth-child(2) { border-left-color: var(--sand); }
.page-about .spec:nth-child(3) { border-left-color: var(--lake-deep); }

.page-about .spec-num {
  font-family: var(--font-mono);
  font-size: 26px;
  font-weight: 700;
  line-height: 1;
  color: var(--lake-deep);
}

.page-about .spec-unit {
  font-size: 0.55em;
  margin-left: 2px;
  color: var(--slate);
}

.page-about .spec-text {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink);
}

/* ================= 服务承诺 ================= */
.page-about .about-pledge {
  background:
    radial-gradient(120% 110% at 88% 0%, rgba(224, 122, 63, 0.18), transparent 58%),
    linear-gradient(168deg, var(--lake-deep), var(--ink));
  color: var(--snow);
}

.page-about .about-pledge .section-title {
  color: var(--snow);
}

.page-about .pledge-grid {
  display: grid;
  gap: 30px;
}

.page-about .pledge-copy p {
  margin: 16px 0 0;
  color: rgba(252, 253, 253, 0.85);
  line-height: 1.85;
}

.page-about .pledge-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .pledge-list li {
  position: relative;
  padding-left: 24px;
  font-size: 14.5px;
  line-height: 1.75;
  color: rgba(252, 253, 253, 0.88);
}

.page-about .pledge-list li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--sand);
}

.page-about .pledge-stats {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
}

.page-about .pledge-stats li {
  padding: 18px 18px 16px;
  border-radius: var(--radius-m);
  background: rgba(232, 241, 244, 0.1);
  border: 1px solid rgba(232, 241, 244, 0.22);
}

.page-about .pledge-stats strong {
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--sand-mist);
}

.page-about .pledge-unit {
  font-family: var(--font-mono);
  font-size: 14px;
  margin-left: 3px;
  color: var(--sand);
}

.page-about .pledge-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: rgba(252, 253, 253, 0.72);
}

/* ================= 下一步 ================= */
.page-about .about-next {
  padding-bottom: 64px;
}

.page-about .next-card {
  display: grid;
  gap: 18px;
  padding: 28px 22px;
  border-radius: var(--radius-l);
  border: 1px solid var(--line);
  background: linear-gradient(150deg, rgba(216, 233, 239, 0.92), rgba(247, 231, 216, 0.78));
}

.page-about .next-copy h2 {
  margin: 12px 0 0;
  font-size: clamp(1.3rem, 3.4vw, 1.7rem);
  line-height: 1.35;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--lake-deep);
}

.page-about .next-copy p {
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
}

.page-about .next-card .btn {
  justify-self: start;
}

.page-about .next-alt {
  margin: 20px 0 0;
  font-size: 14px;
  color: var(--slate);
  line-height: 1.8;
}

.page-about .next-alt a {
  color: var(--sand-deep);
  text-decoration: none;
  border-bottom: 1px solid rgba(168, 73, 28, 0.4);
}

.page-about .next-alt a:hover {
  color: var(--lake);
  border-bottom-color: var(--lake);
}

/* ================= 断点 ================= */
@media (min-width: 640px) {
  .page-about .stat-band {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-about .pledge-stats {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 760px) {
  .page-about .team-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-about .next-card {
    grid-template-columns: 1fr auto;
    align-items: center;
    padding: 32px 30px;
  }

  .page-about .next-copy {
    grid-column: 1 / -1;
  }
}

@media (min-width: 900px) {
  .page-about .about-hero {
    padding: calc(var(--header-h) + 40px) 0 72px;
  }

  .page-about .about-hero-grid {
    grid-template-columns: 1.02fr 0.98fr;
    gap: 56px;
    align-items: end;
  }

  .page-about .mark-grid {
    grid-template-columns: 1fr 360px;
    gap: 64px;
    align-items: center;
  }

  .page-about .mark-stage {
    min-height: 340px;
  }

  .page-about .eco-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 56px;
    align-items: start;
  }

  .page-about .pledge-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 56px;
    align-items: center;
  }

  .page-about .next-alt {
    margin-top: 24px;
  }
}

@media (min-width: 960px) {
  /* 桌面端时间轴改为中轴左右交替 */
  .page-about .timeline::before {
    left: 50%;
    transform: translateX(-1px);
  }

  .page-about .tl-item {
    grid-template-columns: 1fr 132px 1fr;
    column-gap: 0;
    padding-left: 0;
    margin-bottom: 52px;
    align-items: start;
  }

  .page-about .tl-marker {
    grid-column: 2;
    grid-row: 1;
    text-align: center;
    padding-top: 4px;
  }

  .page-about .tl-marker::before {
    left: 50%;
    margin-left: -8px;
    top: -2px;
  }

  .page-about .tl-year {
    display: block;
    padding-top: 22px;
    font-size: 14px;
  }

  .page-about .tl-content {
    grid-column: 1;
    grid-row: 1;
    text-align: right;
    padding-right: 28px;
    padding-left: 24px;
    margin-right: 20px;
  }

  .page-about .tl-note {
    grid-column: 3;
    grid-row: 1;
    border-left: 2px solid var(--mist);
    border-right: 0;
    padding-left: 16px;
    padding-right: 0;
    margin-left: 20px;
    margin-top: 6px;
  }

  .page-about .tl-item:nth-child(even) .tl-content {
    grid-column: 3;
    grid-row: 1;
    text-align: left;
    padding-right: 24px;
    padding-left: 28px;
    margin-right: 0;
    margin-left: 20px;
  }

  .page-about .tl-item:nth-child(even) .tl-note {
    grid-column: 1;
    grid-row: 1;
    text-align: right;
    border-left: 0;
    border-right: 2px solid var(--mist);
    padding-left: 0;
    padding-right: 16px;
    margin-left: 0;
    margin-right: 20px;
  }

  .page-about .tl-item:nth-child(odd) .tl-tags {
    justify-content: flex-end;
  }
}

@media (min-width: 1000px) {
  .page-about .stat-band {
    grid-template-columns: repeat(4, 1fr);
  }
}

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

  .page-about .team-more {
    max-height: 0;
    margin-top: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 320ms var(--ease), opacity 320ms var(--ease), margin-top 320ms var(--ease);
  }

  .page-about .team-cell:hover .team-more,
  .page-about .team-cell:focus-within .team-more,
  .page-about .team-cell:focus .team-more {
    max-height: 190px;
    margin-top: 12px;
    opacity: 1;
  }
}

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

  .page-about .team-cell,
  .page-about .team-more,
  .page-about .year-jump a {
    transition: none;
  }
}