.page-about {
  --about-rail: 208px;
  --about-soft: rgba(237, 230, 216, 0.8);
  --about-hair: rgba(46, 53, 64, 0.72);
  --about-unit: #9a9486;
  padding-bottom: clamp(60px, 9vw, 120px);
  font-family: var(--font-body);
  color: var(--bone);
}

/* ---------- 面包屑留白 ---------- */
.page-about .breadcrumb {
  padding-top: clamp(18px, 3vw, 30px);
}

/* ---------- 框景首屏 ---------- */
.page-about .about-hero {
  margin-top: clamp(14px, 2.6vw, 26px);
}

.page-about .about-hero__frame {
  position: relative;
  border: var(--line);
  padding: clamp(30px, 5.2vw, 66px) clamp(20px, 4vw, 58px) clamp(32px, 5vw, 62px);
  background:
    radial-gradient(120% 92% at 84% -10%, rgba(53, 224, 208, 0.12), transparent 58%),
    radial-gradient(90% 70% at 4% 106%, rgba(181, 113, 90, 0.1), transparent 62%),
    linear-gradient(180deg, #0E2033 0%, #0A1626 100%);
  overflow: hidden;
}

.page-about .about-hero__frame::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 12px;
  background-image: repeating-linear-gradient(90deg, var(--stone) 0 1px, transparent 1px 26px);
  opacity: 0.7;
  pointer-events: none;
}

.page-about .about-hero__frame::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--cyan), transparent);
  opacity: 0.45;
}

.page-about .about-hero__eyebrow {
  color: var(--cyan);
  margin: 0 0 16px;
}

.page-about .about-hero__title {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.02em;
  font-size: clamp(27px, 5.2vw, 52px);
  line-height: 1.16;
  color: var(--bone);
  margin: 0 0 18px;
  max-width: 20ch;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 62ch;
  font-size: clamp(15.5px, 1.7vw, 17.5px);
  line-height: 1.88;
  color: var(--about-soft);
}

.page-about .about-hero__facts {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin: clamp(26px, 4vw, 42px) 0 0;
  padding: 0;
  list-style: none;
  border-top: var(--line);
  border-left: var(--line);
}

.page-about .about-fact {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 15px 16px 17px;
  border-right: var(--line);
  border-bottom: var(--line);
  min-width: 0;
}

.page-about .about-fact__num {
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.6vw, 27px);
  letter-spacing: -0.01em;
  color: var(--bone);
  line-height: 1.2;
}

.page-about .about-fact__label {
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--haze);
}

/* ---------- 主体网格 ---------- */
.page-about .about-body {
  margin-top: clamp(44px, 7vw, 86px);
  display: grid;
  gap: clamp(26px, 4vw, 44px);
}

/* ---------- 侧栏索引 ---------- */
.page-about .about-index {
  display: none;
}

.page-about .about-index__title {
  color: var(--haze);
  margin: 0 0 12px;
}

.page-about .about-index__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--line);
}

.page-about .about-index__item {
  border-bottom: var(--line);
}

.page-about .about-index__link {
  display: block;
  padding: 10px 2px 10px 10px;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--haze);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color 200ms ease, border-color 200ms ease, padding-left 200ms ease;
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible,
.page-about .about-index__link[data-active] {
  color: var(--cyan);
  border-left-color: var(--cyan);
  padding-left: 14px;
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  padding-top: clamp(28px, 4.2vw, 46px);
  border-top: var(--line);
  margin-top: clamp(36px, 6vw, 68px);
}

.page-about .about-stream > .about-section:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.page-about .about-section__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
  margin: 0 0 10px;
}

.page-about .about-section__title {
  font-family: var(--font-display);
  font-weight: 900;
  letter-spacing: -0.015em;
  font-size: clamp(22px, 3.3vw, 33px);
  line-height: 1.3;
  color: var(--bone);
  margin: 0 0 18px;
  max-width: 24ch;
}

.page-about .about-section__lead {
  margin: 0 0 16px;
  max-width: 68ch;
  font-size: clamp(15.5px, 1.6vw, 16.5px);
  line-height: 1.88;
  color: var(--about-soft);
}

.page-about .about-section__text {
  margin: 0 0 22px;
  max-width: 68ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: rgba(237, 230, 216, 0.72);
}

.page-about .about-inline-link {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(53, 224, 208, 0.4);
  transition: border-color 200ms ease;
}

.page-about .about-inline-link:hover {
  border-bottom-color: var(--cyan);
}

/* ---------- 图片容器 ---------- */
.page-about .about-figure {
  margin: 0;
  border: var(--line);
  background: linear-gradient(135deg, #10233A 0%, #0A1626 100%);
  overflow: hidden;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

.page-about .about-figure .media-frame__caption {
  display: block;
  padding: 10px 14px;
  border-top: var(--line);
  font-size: 12px;
  letter-spacing: 0.03em;
  color: var(--haze);
}

.page-about .about-figure--track {
  margin: clamp(16px, 2.4vw, 24px) 0 clamp(24px, 3.6vw, 34px);
}

/* ---------- 团队章节 ---------- */
.page-about .team-split {
  display: grid;
  gap: 26px;
}

.page-about .team-split__main .about-figure {
  margin-top: clamp(18px, 3vw, 26px);
}

.page-about .team-band__title {
  color: var(--haze);
  margin: 0 0 10px;
}

.page-about .team-band {
  list-style: none;
  margin: 0 0 22px;
  padding: 0;
}

.page-about .team-band__row {
  display: grid;
  grid-template-columns: minmax(88px, auto) minmax(0, 1fr) auto;
  align-items: center;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--about-hair);
}

.page-about .team-band__row:first-child {
  border-top: 1px solid var(--about-hair);
}

.page-about .team-band__label {
  font-size: 13px;
  color: var(--about-soft);
  white-space: nowrap;
}

.page-about .team-band__track {
  display: block;
  height: 6px;
  border-radius: 999px;
  background: rgba(46, 53, 64, 0.55);
  overflow: hidden;
}

.page-about .team-band__bar {
  display: block;
  height: 100%;
  border-radius: 999px;
}

.page-about .team-band__bar--moss {
  width: 26%;
  background: var(--moss);
}

.page-about .team-band__bar--clay {
  width: 13%;
  background: var(--clay);
}

.page-about .team-band__bar--haze {
  width: 61%;
  background: var(--haze);
}

.page-about .team-band__value {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--bone);
}

.page-about .team-points {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--line);
}

.page-about .team-points__item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 14px;
  padding: 11px 0;
  border-bottom: var(--line);
}

.page-about .team-points__k {
  font-size: 13px;
  color: var(--haze);
}

.page-about .team-points__v {
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--moss);
  text-align: right;
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  list-style: none;
  margin: 0 0 0 6px;
  padding: 0 0 0 24px;
  border-left: 1px solid var(--stone);
}

.page-about .timeline__item {
  position: relative;
  padding-bottom: 26px;
}

.page-about .timeline__item:last-child {
  padding-bottom: 4px;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  top: 9px;
  left: -27px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--moss);
  box-shadow: 0 0 0 4px var(--ink-800);
  transition: transform 200ms ease, background 200ms ease;
}

.page-about .timeline__item:hover::before,
.page-about .timeline__item:focus-within::before {
  background: var(--cyan);
  transform: scale(1.45);
}

.page-about .timeline__year {
  font-family: var(--font-mono);
  font-size: 18px;
  letter-spacing: 0.06em;
  color: var(--cyan);
  margin: 0 0 6px;
}

.page-about .timeline__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--bone);
  margin: 0 0 6px;
}

.page-about .timeline__text {
  margin: 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.82;
  color: rgba(237, 230, 216, 0.74);
}

/* ---------- 账号类型与服务范围 ---------- */
.page-about .scope-split {
  display: grid;
  gap: 28px;
  margin-top: 6px;
}

.page-about .scope-types {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--about-hair);
}

.page-about .scope-type {
  padding: 18px 0 20px;
  border-bottom: 1px solid var(--about-hair);
}

.page-about .scope-type__name {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17.5px;
  letter-spacing: -0.01em;
  color: var(--bone);
  margin: 0 0 9px;
}

.page-about .scope-type__text {
  margin: 0;
  max-width: 60ch;
  font-size: 15px;
  line-height: 1.82;
  color: rgba(237, 230, 216, 0.76);
}

.page-about .scope-stats {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  border-top: var(--line);
}

.page-about .scope-stat {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 14px;
  padding: 11px 0;
  border-bottom: var(--line);
}

.page-about .scope-stat__num {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--bone);
}

.page-about .scope-stat__label {
  font-size: 12.5px;
  color: var(--haze);
  text-align: right;
}

/* ---------- 产品线技能树 ---------- */
.page-about .tree {
  margin-top: 10px;
}

.page-about .tree__node {
  position: relative;
  border: var(--line);
  border-left: 2px solid var(--stone);
  background: linear-gradient(180deg, rgba(16, 35, 58, 0.92) 0%, rgba(10, 22, 38, 0.92) 100%);
  margin-bottom: 14px;
  transition: border-left-color 200ms ease;
}

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

.page-about .tree__node[open] {
  border-left-color: var(--cyan);
}

.page-about .tree__node:hover {
  border-left-color: var(--cyan);
}

.page-about .tree__node:not(:last-child)::after {
  content: "";
  position: absolute;
  left: -2px;
  bottom: -15px;
  width: 1px;
  height: 15px;
  background: var(--stone);
}

.page-about .tree__summary {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 17px 18px;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17px;
  letter-spacing: -0.01em;
  color: var(--bone);
}

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

.page-about .tree__summary:focus-visible {
  outline: 1px solid var(--cyan);
  outline-offset: -1px;
}

.page-about .tree__index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--haze);
  flex: 0 0 auto;
}

.page-about .tree__name {
  flex: 1 1 auto;
  min-width: 0;
}

.page-about .tree__detail {
  padding: 0 20px 20px;
  border-top: 1px solid var(--about-hair);
  margin-top: 0;
}

.page-about .tree__detail p {
  margin: 16px 0 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.85;
  color: rgba(237, 230, 216, 0.76);
}

/* ---------- 适配与质量 ---------- */
.page-about .quality-grid {
  display: grid;
  gap: 1px;
  background: var(--about-hair);
  border: var(--line);
  margin: 0 0 28px;
}

.page-about .quality-cell {
  background: var(--ink-800);
  padding: 20px 18px 22px;
}

.page-about .quality-cell__num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 44px);
  letter-spacing: -0.02em;
  line-height: 1;
  color: var(--bone);
  margin: 0 0 10px;
}

.page-about .quality-cell__unit {
  font-size: 0.42em;
  letter-spacing: 0.06em;
  color: var(--cyan);
  margin-left: 6px;
}

.page-about .quality-cell__label {
  margin: 0;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--haze);
}

.page-about .about-metrics__title {
  color: var(--haze);
  margin: 0 0 10px;
}

.page-about .about-metrics {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--line);
}

.page-about .about-metrics__item {
  display: grid;
  gap: 4px;
  padding: 13px 0;
  border-bottom: var(--line);
}

.page-about .about-metrics__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 15px;
  color: var(--bone);
}

.page-about .about-metrics__desc {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--about-soft);
}

/* ---------- 资质与合作 ---------- */
.page-about .creds {
  list-style: none;
  display: grid;
  gap: 12px;
  margin: 4px 0 0;
  padding: 0;
}

.page-about .creds__item {
  border: 1px solid rgba(237, 230, 216, 0.22);
  background: rgba(16, 35, 58, 0.5);
  padding: 15px 18px 17px;
}

.page-about .creds__key {
  color: var(--haze);
  margin: 0 0 7px;
}

.page-about .creds__val {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.75;
  color: var(--bone);
}

/* ---------- 尾部行动区 ---------- */
.page-about .about-cta {
  position: relative;
  margin-top: clamp(46px, 7vw, 88px);
  border: var(--line);
  padding: clamp(22px, 3.6vw, 38px) clamp(20px, 3.6vw, 38px);
  background: linear-gradient(100deg, rgba(16, 35, 58, 0.95) 0%, rgba(10, 22, 38, 0.95) 66%);
  overflow: hidden;
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: linear-gradient(180deg, var(--cyan) 0%, var(--amber) 100%);
}

.page-about .about-cta__text {
  margin: 0 0 20px;
  max-width: 70ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--about-soft);
}

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

/* ---------- 平板 ---------- */
@media (min-width: 700px) {
  .page-about .about-hero__facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

  .page-about .about-metrics__item {
    grid-template-columns: minmax(150px, 0.34fr) minmax(0, 1fr);
    align-items: baseline;
    gap: 18px;
  }

  .page-about .scope-split {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: 40px;
    align-items: start;
  }
}

/* ---------- 桌面 ---------- */
@media (min-width: 860px) {
  .page-about .team-split {
    grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.9fr);
    gap: 44px;
    align-items: start;
  }

  .page-about .timeline {
    margin-left: 8px;
    padding-left: 30px;
  }

  .page-about .timeline__item::before {
    left: -33px;
  }
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: clamp(36px, 5vw, 72px);
  }

  .page-about .about-index {
    display: block;
    position: sticky;
    top: 96px;
    align-self: start;
  }
}
<<<END>>>