.page-about {
  --about-num-size: clamp(30px, 4.6vw, 48px);
  --about-hair: 1px solid var(--line);
  padding-bottom: clamp(36px, 5vw, 72px);
}

.page-about .about-crumb {
  padding-top: clamp(16px, 3vw, 28px);
}

.page-about .about-eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--teal);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 3.4vw, 40px) 0 clamp(10px, 2vw, 18px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 360px;
  background-image:
    repeating-linear-gradient(90deg, var(--grid-line) 0 1px, transparent 1px 24px),
    repeating-linear-gradient(0deg, var(--grid-line) 0 1px, transparent 1px 24px);
  -webkit-mask-image: linear-gradient(to bottom, #000 0%, transparent 100%);
  mask-image: linear-gradient(to bottom, #000 0%, transparent 100%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(22px, 3.4vw, 40px);
}

.page-about .about-h1 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(34px, 6.6vw, 66px);
  line-height: 1.04;
  letter-spacing: -.01em;
  color: var(--heading);
}

.page-about .about-lede {
  margin: 18px 0 0;
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-dim);
}

.page-about .about-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-hero-aside {
  border-left: 2px solid var(--teal-deep);
  padding-left: 18px;
}

.page-about .about-aside-kicker {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .2em;
  color: var(--amber);
}

.page-about .about-aside-text {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-dim);
}

.page-about .about-aside-link {
  display: inline-block;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--teal);
  text-decoration: none;
  border-bottom: 1px dashed var(--teal-deep);
  padding-bottom: 2px;
}

.page-about .about-aside-link:hover,
.page-about .about-aside-link:focus-visible {
  color: var(--ice);
  border-bottom-color: var(--teal);
}

.page-about .about-stats {
  position: relative;
  z-index: 1;
  list-style: none;
  margin: clamp(26px, 4vw, 44px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: var(--about-hair);
}

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

.page-about .about-stat-num {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 38px);
  font-weight: 700;
  line-height: 1;
  color: var(--ice);
}

.page-about .about-stat-num em {
  font-style: normal;
  color: var(--teal);
  font-size: .7em;
  margin-left: 2px;
}

.page-about .about-stat-label {
  font-size: 13px;
  line-height: 1.5;
  letter-spacing: .02em;
  color: var(--text-dim);
}

/* ---------- 章节通用 ---------- */

.page-about .about-section {
  padding: clamp(38px, 5.6vw, 72px) 0 0;
}

.page-about .about-section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 12px 18px;
  padding-bottom: 14px;
  margin-bottom: clamp(20px, 3vw, 32px);
  border-bottom: var(--about-hair);
}

.page-about .about-secnum {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: var(--about-num-size);
  font-weight: 700;
  line-height: .95;
  letter-spacing: .02em;
  color: transparent;
  -webkit-text-stroke: 1.4px var(--teal-deep);
}

.page-about .about-head-text {
  min-width: 0;
  padding-top: 4px;
}

.page-about .about-head-text h2 {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: clamp(23px, 3.4vw, 33px);
  font-weight: 700;
  line-height: 1.18;
  color: var(--heading);
}

/* ---------- 版本时间轴 ---------- */

.page-about .about-timeline {
  position: relative;
  overflow: hidden;
}

.page-about .about-timeline-bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: .16;
  pointer-events: none;
  z-index: 0;
}

.page-about .about-tl-list {
  position: relative;
  z-index: 1;
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-tl-details {
  height: 100%;
  background: var(--surface);
  border: var(--about-hair);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
  transition: background-color .2s ease, border-color .2s ease;
}

.page-about .about-tl-details[open] {
  background: var(--surface-alt);
  border-color: var(--teal-deep);
}

.page-about .about-tl-summary {
  position: relative;
  display: block;
  cursor: pointer;
  list-style: none;
  padding: clamp(18px, 2.4vw, 26px) clamp(44px, 4vw, 52px) clamp(18px, 2.4vw, 26px) clamp(18px, 2.4vw, 26px);
}

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

.page-about .about-tl-summary::after {
  content: "+";
  position: absolute;
  top: clamp(16px, 2.2vw, 22px);
  right: clamp(16px, 2.2vw, 22px);
  width: 24px;
  height: 24px;
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  line-height: 1;
  color: var(--teal);
  border: 1px solid var(--teal-deep);
  transition: transform .2s ease, background-color .2s ease, color .2s ease;
}

.page-about .about-tl-details[open] .about-tl-summary::after {
  content: "−";
  background: var(--teal);
  color: var(--on-accent);
  border-color: var(--teal);
}

.page-about .about-tl-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .14em;
  padding: 3px 10px;
  color: var(--on-accent);
  background: var(--teal);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 6px 100%, 0 calc(100% - 6px));
}

.page-about .about-tl-item:nth-child(2) .about-tl-tag {
  background: var(--amber);
  color: var(--brown);
}

.page-about .about-tl-item:nth-child(3) .about-tl-tag {
  background: var(--coral);
  color: var(--brown);
}

.page-about .about-tl-title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(20px, 2.4vw, 25px);
  font-weight: 700;
  line-height: 1.24;
  color: var(--heading);
}

.page-about .about-tl-desc {
  margin: 10px 0 0;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-dim);
}

.page-about .about-tl-changes {
  list-style: none;
  margin: 0;
  padding: 14px clamp(18px, 2.4vw, 26px) clamp(18px, 2.4vw, 26px);
  display: grid;
  gap: 10px;
  border-top: 1px dashed var(--line);
}

.page-about .about-tl-changes li {
  position: relative;
  padding-left: 18px;
  font-size: 16px;
  line-height: 1.65;
  color: var(--text-dim);
}

.page-about .about-tl-changes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .62em;
  width: 7px;
  height: 7px;
  background: var(--teal);
  clip-path: polygon(0 0, 100% 0, 0 100%);
}

/* ---------- 团队与分工 ---------- */

.page-about .about-team-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(18px, 2.6vw, 30px);
}

.page-about .about-team-cards {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
}

.page-about .about-file {
  display: grid;
  gap: 10px;
  padding: clamp(18px, 2.4vw, 26px);
  background: var(--cream);
  color: var(--brown);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
  transition: transform .2s ease, box-shadow .2s ease;
}

.page-about .about-file:hover,
.page-about .about-file:focus-within {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}

.page-about .about-file-num {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--coral);
  color: #1C1710;
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  line-height: 1;
}

.page-about .about-file-title {
  margin: 0;
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--brown);
}

.page-about .about-file-text {
  margin: 0;
  font-size: 16px;
  line-height: 1.75;
  color: #4A4132;
}

.page-about .about-team-figure {
  margin: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-team-media {
  overflow: hidden;
  border: var(--about-hair);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
}

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

.page-about .about-team-figure figcaption {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-dim);
  border-left: 2px solid var(--amber);
  padding-left: 12px;
}

/* ---------- 服务承诺 ---------- */

.page-about .about-promises {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 14px;
  counter-reset: none;
}

.page-about .about-promise {
  position: relative;
  padding: 20px 20px 22px 20px;
  background: linear-gradient(160deg, var(--signal-soft), transparent 62%);
  border: var(--about-hair);
  border-left: 2px solid var(--teal-deep);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
}

.page-about .about-promise-idx {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--amber);
}

.page-about .about-promise-title {
  margin: 8px 0 0;
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 700;
  line-height: 1.22;
  color: var(--heading);
}

.page-about .about-promise-text {
  margin: 10px 0 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text-dim);
}

/* ---------- 更新节奏 ---------- */

.page-about .about-cadence-figure {
  margin: 0 0 clamp(18px, 2.6vw, 28px);
  overflow: hidden;
  border: var(--about-hair);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
}

.page-about .about-cadence-figure img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
  aspect-ratio: 2 / 1;
}

.page-about .about-cadence-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 1px;
  background: var(--line);
  border: var(--about-hair);
}

.page-about .about-cadence-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 10px;
  padding: 18px;
  background: var(--surface);
}

.page-about .about-cadence-num {
  font-family: var(--font-mono);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  line-height: 1;
  color: var(--ice);
}

.page-about .about-cadence-num small {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .1em;
  color: var(--amber);
  margin-left: 6px;
}

.page-about .about-cadence-body h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.24;
  color: var(--heading);
}

.page-about .about-cadence-body p {
  margin: 8px 0 0;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text-dim);
}

/* ---------- 路线图 ---------- */

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

.page-about .about-road-item {
  background: var(--surface);
  border: var(--about-hair);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
  transition: border-color .2s ease, background-color .2s ease;
}

.page-about .about-road-item[open] {
  border-color: var(--teal-deep);
  background: var(--surface-alt);
}

.page-about .about-road-summary {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 14px;
  cursor: pointer;
  list-style: none;
  padding: 16px 46px 16px 18px;
}

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

.page-about .about-road-summary::after {
  content: "▾";
  position: absolute;
  top: 50%;
  right: 18px;
  transform: translateY(-50%);
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--teal);
  transition: transform .2s ease;
}

.page-about .about-road-item[open] .about-road-summary::after {
  transform: translateY(-50%) rotate(180deg);
}

.page-about .about-road-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .14em;
  color: var(--brown);
  background: var(--amber);
  padding: 3px 8px;
  clip-path: polygon(0 0, 100% 0, 100% 100%, 6px 100%, 0 calc(100% - 6px));
}

.page-about .about-road-summary h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.24;
  color: var(--heading);
}

.page-about .about-road-state {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--teal);
  margin-left: auto;
}

.page-about .about-road-item p {
  margin: 0;
  padding: 0 18px 18px;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text-dim);
  border-top: 1px dashed var(--line);
  padding-top: 14px;
}

/* ---------- 收尾 ---------- */

.page-about .about-endcap {
  margin-top: clamp(28px, 4vw, 44px);
  padding: clamp(20px, 3vw, 30px);
  border: 1px solid var(--teal-deep);
  background: var(--signal-soft);
  clip-path: polygon(0 0, calc(100% - var(--cut)) 0, 100% var(--cut), 100% 100%, var(--cut) 100%, 0 calc(100% - var(--cut)));
}

.page-about .about-endcap p {
  margin: 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text);
}

.page-about .about-endcap-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

/* ---------- 媒体查询 ---------- */

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

  .page-about .about-cadence-item {
    grid-template-columns: minmax(0, 150px) minmax(0, 1fr);
    align-items: start;
    gap: 18px;
    padding: 20px 22px;
  }
}

@media (min-width: 860px) {
  .page-about .about-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

@media (min-width: 980px) {
  .page-about .about-hero-inner {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-about .about-team-grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-section-head {
    flex-wrap: nowrap;
    gap: 24px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-file,
  .page-about .about-tl-details,
  .page-about .about-tl-summary::after,
  .page-about .about-road-item,
  .page-about .about-road-summary::after {
    transition: none;
  }

  .page-about .about-file:hover,
  .page-about .about-file:focus-within {
    transform: none;
  }
}
<<<PAGE_CSS_END>>>