.page-about {
  --about-measure: 58ch;
  --about-rail-w: 22px;
  display: block;
  background: var(--c-base);
  color: var(--c-ink);
}

/* ============ 右侧章节轨道 ============ */
.page-about .page-about__rail {
  position: fixed;
  top: 50%;
  right: 8px;
  transform: translateY(-50%);
  display: none;
  flex-direction: row;
  align-items: flex-start;
  gap: 4px;
  z-index: 30;
  padding: 0;
  margin: 0;
}

@media (min-width: 1100px) {
  .page-about .page-about__rail {
    display: flex;
  }
}

.page-about .page-about__rail .chapter-rail__link {
  writing-mode: vertical-rl;
  text-orientation: upright;
  font-size: 10px;
  line-height: 1;
  letter-spacing: .1em;
  color: var(--c-slate);
  text-decoration: none;
  padding: 8px 4px;
  border-left: 1px solid var(--line-ink);
  transition: color var(--dur), border-color var(--dur);
}

.page-about .page-about__rail .chapter-rail__link:hover {
  color: var(--c-ink);
  border-left-color: var(--c-steel);
}

.page-about .page-about__rail .chapter-rail__link[data-active="true"] {
  color: var(--c-pottery);
  border-left-color: var(--c-pottery);
}

/* ============ 首屏 ============ */
.page-about .about-hero {
  padding: 48px 0 64px;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 40px;
}

@media (min-width: 940px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 64px;
    align-items: start;
  }
}

.page-about .about-hero__main {
  min-width: 0;
}

.page-about .about-hero__eyebrow {
  display: block;
  margin: 28px 0 0;
  color: var(--c-slate);
}

.page-about .about-hero__title {
  margin: 18px 0 0;
  letter-spacing: -.015em;
}

.page-about .about-hero__lede {
  margin: 18px 0 0;
  max-width: 26ch;
  color: var(--c-moss);
}

.page-about .about-hero__intro {
  margin: 26px 0 0;
  max-width: var(--about-measure);
}

.page-about .about-hero__media {
  min-width: 0;
  margin: 0;
}

@media (min-width: 940px) {
  .page-about .about-hero__media {
    margin-top: 84px;
  }
}

/* ============ 通用数据行 ============ */
.page-about .spec {
  margin: 40px 0 0;
  padding: 0;
}

.page-about .spec__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 20px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-ink);
}

.page-about .spec__row:first-child {
  border-top: 1px solid var(--line-ink-2);
}

.page-about .spec__k {
  margin: 0;
  font-size: 13px;
  letter-spacing: .04em;
  color: var(--c-slate);
}

.page-about .spec__v {
  margin: 0;
  font-size: 16px;
  color: var(--c-ink);
  text-align: right;
}

/* ============ 起点 ============ */
.page-about .about-origin {
  padding-top: 72px;
  padding-bottom: 56px;
}

.page-about .about-origin__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 24px;
}

@media (min-width: 860px) {
  .page-about .about-origin__grid {
    grid-template-columns: 64px minmax(0, 1fr);
    gap: 40px;
  }
}

.page-about .about-origin__side {
  margin: 6px 0 0;
  color: var(--c-steel);
}

@media (max-width: 859px) {
  .page-about .about-origin__side {
    writing-mode: horizontal-tb;
  }
}

.page-about .about-origin__prose {
  margin-top: 28px;
  max-width: var(--about-measure);
}

.page-about .about-origin__prose p {
  margin: 0 0 1.5em;
}

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

/* ============ 引用式大字 ============ */
.page-about .about-pull {
  padding: 72px 0;
  border-top: 1px solid var(--line-ink);
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-pull__text {
  margin: 0;
  max-width: 20ch;
  color: var(--c-moss);
  border-left: 6px solid var(--c-terra);
  padding-left: 28px;
}

/* ============ 沿革阶段 ============ */
.page-about .about-stages {
  padding-top: 72px;
  padding-bottom: 80px;
}

.page-about .about-stages__lead {
  margin: 24px 0 0;
  max-width: 44ch;
  color: var(--c-slate);
}

.page-about .stages {
  list-style: none;
  margin: 56px 0 0;
  padding: 0;
  border-top: 1px solid var(--line-ink-2);
}

.page-about .stage {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 20px;
  padding: 36px 0;
  border-bottom: 1px solid var(--line-ink);
  --sc: var(--c-terra);
}

.page-about .stage--1 { --sc: var(--c-terra); }
.page-about .stage--2 { --sc: var(--c-plateau); }
.page-about .stage--3 { --sc: var(--c-pottery); }
.page-about .stage--4 { --sc: var(--c-moss); }

@media (min-width: 780px) {
  .page-about .stage {
    grid-template-columns: 108px minmax(0, 1fr);
    gap: 48px;
    padding: 48px 0;
  }
}

@media (min-width: 780px) {
  .page-about .stage--2 { padding-left: 20px; }
  .page-about .stage--3 { padding-left: 40px; }
  .page-about .stage--4 { padding-left: 60px; }
}

.page-about .stage__mark {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.page-about .stage__num {
  font-size: clamp(34px, 5vw, 48px);
  line-height: .9;
  letter-spacing: -.02em;
  color: var(--sc);
}

.page-about .stage__body {
  min-width: 0;
}

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

.page-about .stage__text {
  margin: 16px 0 0;
  max-width: var(--about-measure);
  font-size: 17px;
  line-height: 1.9;
}

.page-about .stage__more {
  margin-top: 22px;
  max-width: var(--about-measure);
}

.page-about .stage__more > summary {
  cursor: pointer;
  list-style: none;
  padding: 10px 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--c-plateau);
  border-top: 1px dashed var(--line-ink-2);
  border-bottom: 1px solid var(--line-ink);
  transition: color var(--dur);
}

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

.page-about .stage__more > summary::before {
  content: "+ ";
  color: var(--sc);
}

.page-about .stage__more[open] > summary::before {
  content: "− ";
}

.page-about .stage__more > summary:hover {
  color: var(--c-ink);
}

.page-about .stage__more .spec {
  margin-top: 4px;
}

.page-about .about-stages__figure {
  margin: 56px 0 0;
}

@media (min-width: 780px) {
  .page-about .about-stages__figure {
    margin-left: 156px;
    max-width: 720px;
  }
}

/* ============ 员工规模 ============ */
.page-about .about-people {
  padding-top: 72px;
  padding-bottom: 80px;
}

.page-about .about-people__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 40px;
  margin-top: 40px;
}

@media (min-width: 900px) {
  .page-about .about-people__grid {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    gap: 56px;
    align-items: start;
  }
}

.page-about .about-people__main {
  min-width: 0;
}

.page-about .about-people__lead {
  margin: 0;
  max-width: var(--about-measure);
}

.page-about .about-people__text {
  margin: 22px 0 0;
  max-width: var(--about-measure);
}

.page-about .about-people__media {
  margin: 0;
  min-width: 0;
}

.page-about .staffbar {
  margin-top: 44px;
  max-width: 640px;
}

.page-about .staffbar__label {
  display: block;
  margin: 0 0 12px;
  color: var(--c-slate);
}

.page-about .staffbar__track {
  display: flex;
  height: 30px;
  border: 1px solid var(--line-ink-2);
  background: var(--c-rock);
}

.page-about .staffbar__seg {
  position: relative;
  display: block;
  height: 100%;
}

.page-about .staffbar__seg--tech {
  width: 60.2%;
  background: var(--c-terra);
}

.page-about .staffbar__seg--rest {
  width: 39.8%;
  background: repeating-linear-gradient(
    45deg,
    var(--c-rock) 0 6px,
    var(--c-base) 6px 12px
  );
  border-left: 1px solid var(--line-ink-2);
}

.page-about .staffbar__tip {
  position: absolute;
  left: 0;
  bottom: calc(100% + 8px);
  white-space: nowrap;
  font-size: 11px;
  letter-spacing: .04em;
  line-height: 1.5;
  color: var(--c-base);
  background: var(--c-moss);
  padding: 5px 10px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(4px);
  transition: opacity var(--dur), transform var(--dur), visibility var(--dur);
  z-index: 5;
}

.page-about .staffbar__seg:hover .staffbar__tip,
.page-about .staffbar__seg:focus-within .staffbar__tip {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.page-about .staffbar__legend {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
}

.page-about .staffbar__item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--c-slate);
}

.page-about .staffbar__dot {
  display: inline-block;
  width: 10px;
  height: 10px;
  flex: 0 0 auto;
}

.page-about .staffbar__dot--tech { background: var(--c-terra); }
.page-about .staffbar__dot--rest {
  background: var(--c-rock);
  border: 1px solid var(--line-ink-2);
}
.page-about .staffbar__dot--total { background: var(--c-moss); }

.page-about .staffbar__num {
  color: var(--c-ink);
  font-size: 14px;
}

/* ============ 认证编号 ============ */
.page-about .about-cert {
  padding-top: 72px;
  padding-bottom: 80px;
  color: var(--c-base);
}

.page-about .about-cert__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 44px;
  margin-top: 40px;
}

@media (min-width: 900px) {
  .page-about .about-cert__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 64px;
    align-items: start;
  }
}

.page-about .about-cert__lead {
  margin: 0;
  max-width: 44ch;
  font-size: 18px;
  line-height: 1.9;
  color: var(--c-base);
}

.page-about .about-cert__text {
  margin: 22px 0 0;
  max-width: var(--about-measure);
  font-size: 15px;
  line-height: 1.9;
  color: var(--cream);
}

.page-about .about-cert__code {
  min-width: 0;
}

.page-about .certcode__display {
  margin: 0 0 24px;
  font-size: clamp(24px, 4.4vw, 46px);
  line-height: 1.1;
  letter-spacing: .02em;
  color: var(--c-base);
  word-break: break-all;
  border-bottom: 1px solid var(--line-cream);
  padding-bottom: 20px;
}

.page-about .certcode {
  margin: 0;
  display: grid;
  gap: 0;
}

.page-about .certcode__row {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  gap: 20px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--line-cream);
}

.page-about .certcode__row dt {
  margin: 0;
  font-size: 16px;
  color: var(--c-terra);
  letter-spacing: .04em;
}

.page-about .certcode__row dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--cream);
}

/* ============ 服务条款双轨 ============ */
.page-about .about-sla {
  padding-top: 72px;
  padding-bottom: 80px;
}

.page-about .about-sla__lead {
  margin: 24px 0 0;
  max-width: 56ch;
}

.page-about .sla {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  margin-top: 48px;
  border-top: 1px solid var(--line-ink-2);
}

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

.page-about .sla__col {
  padding: 32px 0;
  border-bottom: 1px solid var(--line-ink);
  --sc: var(--c-terra);
}

.page-about .sla__col--std { --sc: var(--c-terra); }
.page-about .sla__col--rt { --sc: var(--c-alert); }

@media (min-width: 860px) {
  .page-about .sla__col--std {
    padding-right: 48px;
    border-right: 1px solid var(--line-ink);
  }
  .page-about .sla__col--rt {
    padding-left: 48px;
  }
}

.page-about .sla__tag {
  margin: 0 0 16px;
  color: var(--sc);
  border-left: 3px solid var(--sc);
  padding-left: 10px;
}

.page-about .sla__col .ttl--sm {
  margin: 0 0 20px;
}

.page-about .sla__col .body-sm {
  margin: 20px 0 0;
  max-width: 46ch;
  color: var(--c-slate);
}

.page-about .about-sla__more {
  margin: 32px 0 0;
  max-width: var(--about-measure);
  font-size: 14px;
  line-height: 1.9;
  color: var(--c-slate);
}

.page-about .about-sla__more a,
.page-about .about-cadence__more a {
  color: var(--c-pottery);
  text-decoration: none;
  border-bottom: 1px solid currentColor;
  padding-bottom: 1px;
  transition: color var(--dur);
}

.page-about .about-sla__more a:hover,
.page-about .about-cadence__more a:hover {
  color: var(--c-ink);
}

/* ============ 更新节奏 ============ */
.page-about .about-cadence {
  padding-top: 72px;
  padding-bottom: 72px;
}

.page-about .about-cadence__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 44px;
  margin-top: 40px;
}

@media (min-width: 900px) {
  .page-about .about-cadence__grid {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    gap: 64px;
    align-items: start;
  }
}

.page-about .about-cadence__intro {
  margin: 0;
  max-width: 40ch;
  font-size: 16px;
  line-height: 1.95;
}

.page-about .cadence {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-ink-2);
}

.page-about .cadence__item {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 20px;
  padding: 22px 0;
  border-bottom: 1px solid var(--line-ink);
}

@media (min-width: 620px) {
  .page-about .cadence__item {
    grid-template-columns: 92px minmax(0, 1fr);
    gap: 32px;
  }
}

.page-about .cadence__key {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--c-plateau);
  padding-top: 3px;
}

.page-about .cadence__body {
  min-width: 0;
}

.page-about .cadence__title {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: .02em;
}

.page-about .cadence__body p {
  margin: 10px 0 0;
  max-width: var(--about-measure);
  font-size: 14px;
  line-height: 1.9;
  color: var(--c-slate);
}

.page-about .about-cadence__more {
  margin: 32px 0 0;
  font-size: 14px;
  line-height: 1.9;
  color: var(--c-slate);
}

/* ============ 延伸入口 ============ */
.page-about .about-next {
  padding-top: 56px;
  padding-bottom: 72px;
}

.page-about .about-next__title {
  margin: 0 0 28px;
  color: var(--c-slate);
}

.page-about .about-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line-ink-2);
}

.page-about .about-next__item {
  border-bottom: 1px solid var(--line-ink);
}

.page-about .about-next__link {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 24px;
  padding: 18px 0;
  text-decoration: none;
  color: var(--c-ink);
  transition: color var(--dur), padding-left var(--dur);
}

.page-about .about-next__link:hover {
  color: var(--c-pottery);
  padding-left: 8px;
}

.page-about .about-next__label {
  font-size: 17px;
  letter-spacing: .02em;
}

.page-about .about-next__meta {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--c-steel);
}

@media (max-width: 480px) {
  .page-about .about-hero {
    padding: 32px 0 48px;
  }

  .page-about .about-pull__text {
    padding-left: 18px;
    border-left-width: 4px;
  }

  .page-about .stage__text {
    font-size: 16px;
  }

  .page-about .certcode__row {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 14px;
  }

  .page-about .staffbar__tip {
    white-space: normal;
    width: 200px;
  }
}
<<<END>>>