.page-about {
  --ab-rail-w: 206px;
  --ab-line: rgba(143, 167, 155, .26);
  --ab-line-soft: rgba(143, 167, 155, .13);
  --ab-text-soft: rgba(232, 226, 212, .82);
  --ab-text-dim: rgba(232, 226, 212, .7);
  position: relative;
  overflow-x: clip;
  background: var(--c-dusk);
  color: var(--c-paper);
  font-family: var(--font-body);
}

.page-about .ab-crumb {
  padding-top: 16px;
}

.page-about .ab-inline-link {
  color: var(--c-gold);
  text-decoration: none;
  border-bottom: 1px solid rgba(216, 169, 75, .45);
}

.page-about .ab-inline-link:hover {
  color: var(--c-gold-lift);
  border-bottom-color: var(--c-gold-lift);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: clamp(30px, 5.5vw, 72px) 0 clamp(28px, 4.5vw, 56px);
  background:
    radial-gradient(120% 100% at 88% -25%, rgba(30, 74, 59, .92) 0%, rgba(16, 26, 26, 0) 62%),
    repeating-linear-gradient(90deg, rgba(143, 167, 155, .06) 0 1px, transparent 1px 96px),
    linear-gradient(180deg, #101A1A 0%, #0E1817 100%);
}

.page-about .ab-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--c-gold) 0 72px, var(--ab-line) 72px 100%);
}

.page-about .pj-eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--c-gold);
}

.page-about .ab-hero__title {
  margin: 14px 0 0;
  max-width: 17em;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(30px, 6.2vw, 60px);
  line-height: 1.18;
  letter-spacing: -.01em;
}

.page-about .ab-hero__title span {
  display: block;
  color: var(--c-gold);
}

.page-about .ab-hero__lead {
  margin: clamp(16px, 2.4vw, 24px) 0 0;
  max-width: 58ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.85;
  color: var(--ab-text-soft);
}

.page-about .ab-hero__marks {
  list-style: none;
  margin: clamp(22px, 3.6vw, 40px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ab-line);
  border: 1px solid var(--ab-line);
}

.page-about .ab-mark {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 14px 16px 16px;
  background: rgba(20, 46, 39, .58);
}

.page-about .ab-mark__year {
  font-family: var(--font-mono);
  font-size: 21px;
  letter-spacing: .02em;
  color: var(--c-gold);
}

.page-about .ab-mark__text {
  font-size: 13px;
  line-height: 1.6;
  color: var(--ab-text-dim);
}

@media (min-width: 700px) {
  .page-about .ab-hero__marks {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 阶段索引条 ---------- */
.page-about .ab-index {
  background: #0E1817;
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-index__inner {
  display: flex;
  gap: 1px;
  overflow-x: auto;
  padding-left: 0;
  padding-right: 0;
  scrollbar-width: thin;
}

.page-about .ab-index__item {
  flex: 0 0 auto;
  min-width: 128px;
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 13px 16px 14px;
  border-top: 2px solid transparent;
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .ab-index__item .pj-mono {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--c-gold);
}

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

.page-about .ab-index__item:hover,
.page-about .ab-index__item:focus-visible {
  border-top-color: var(--c-gold);
  background: rgba(216, 169, 75, .09);
}

/* ---------- 主体布局 ---------- */
.page-about .ab-body {
  padding-bottom: clamp(28px, 5vw, 64px);
}

.page-about .ab-rail {
  display: none;
}

.page-about .ab-stages {
  min-width: 0;
}

@media (min-width: 980px) {
  .page-about .ab-body {
    display: grid;
    grid-template-columns: var(--ab-rail-w) minmax(0, 1fr);
    column-gap: clamp(26px, 4vw, 60px);
    align-items: start;
  }

  .page-about .ab-rail {
    display: block;
    position: sticky;
    top: 24px;
    padding-top: clamp(34px, 4.6vw, 58px);
  }
}

.page-about .ab-rail__title {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .2em;
  color: var(--c-zinc);
}

.page-about .ab-rail__list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-left: 1px solid var(--ab-line);
}

.page-about .ab-rail__link {
  display: flex;
  flex-direction: column;
  gap: 3px;
  margin-left: -1px;
  padding: 9px 0 10px 16px;
  border-left: 2px solid transparent;
  text-decoration: none;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .ab-rail__year {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--c-gold);
}

.page-about .ab-rail__label {
  font-size: 14px;
  color: var(--ab-text-soft);
}

.page-about .ab-rail__link:hover,
.page-about .ab-rail__link:focus-visible {
  border-left-color: var(--c-gold);
  background: rgba(216, 169, 75, .07);
}

/* ---------- 章节 ---------- */
.page-about .ab-stage {
  position: relative;
  padding: clamp(32px, 4.6vw, 62px) 0;
  border-top: 1px solid var(--ab-line-soft);
}

.page-about .ab-stages .ab-stage:first-child {
  border-top: 0;
}

.page-about .ab-stage__band {
  width: 74px;
  height: 3px;
  margin-bottom: 20px;
  background: var(--c-gold);
}

.page-about .ab-stages .ab-stage:nth-child(even) .ab-stage__band {
  width: 42px;
  background: var(--c-clay);
}

.page-about .ab-stage__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: 14px;
  align-items: baseline;
  margin-bottom: clamp(18px, 2.6vw, 28px);
}

.page-about .ab-stage__num {
  font-family: var(--font-mono);
  font-size: clamp(24px, 3.2vw, 38px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--c-gold);
}

.page-about .ab-stage__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.3;
}

.page-about .ab-stage__meta {
  grid-column: 1 / -1;
  margin: 9px 0 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--c-zinc);
}

.page-about .ab-stage__text p {
  margin: 0 0 1em;
  max-width: 62ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--ab-text-soft);
}

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

.page-about .ab-stage__text .ab-inline-link {
  color: var(--c-gold);
}

@media (min-width: 760px) {
  .page-about .ab-stage__grid {
    display: grid;
    grid-template-columns: minmax(0, 1.06fr) minmax(0, .94fr);
    gap: clamp(22px, 3.4vw, 46px);
    align-items: start;
  }

  .page-about .ab-stage__grid--flip > .ab-figure {
    order: -1;
  }
}

/* ---------- 图片框 ---------- */
.page-about .ab-figure {
  margin: clamp(20px, 3vw, 26px) 0 0;
  border: 1px solid var(--ab-line);
  background:
    repeating-linear-gradient(0deg, rgba(143, 167, 155, .08) 0 1px, transparent 1px 40px),
    repeating-linear-gradient(90deg, rgba(143, 167, 155, .08) 0 1px, transparent 1px 40px),
    linear-gradient(155deg, rgba(30, 74, 59, .62), rgba(11, 17, 16, .94));
}

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

.page-about .ab-figure__cap {
  margin: 0;
  padding: 10px 12px;
  border-top: 1px solid var(--ab-line-soft);
  font-family: var(--font-mono);
  font-size: 10.5px;
  line-height: 1.6;
  letter-spacing: .06em;
  color: var(--c-zinc);
}

@media (min-width: 760px) {
  .page-about .ab-figure {
    margin-top: 4px;
  }
}

/* ---------- 条目列表 ---------- */
.page-about .ab-list {
  list-style: none;
  margin: 18px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ab-line-soft);
}

.page-about .ab-list li {
  position: relative;
  padding: 11px 14px 11px 26px;
  background: rgba(20, 46, 39, .46);
  font-size: 14px;
  line-height: 1.7;
  color: var(--ab-text-soft);
}

.page-about .ab-list li::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 18px;
  width: 6px;
  height: 6px;
  background: var(--c-gold);
}

/* ---------- 方法三卡 ---------- */
.page-about .ab-method {
  list-style: none;
  margin: clamp(20px, 3.2vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(10px, 1.6vw, 16px);
}

.page-about .ab-method__item {
  padding: 17px 18px 20px;
  border-top: 2px solid var(--c-gold);
  background: rgba(20, 46, 39, .55);
}

.page-about .ab-method__k {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .2em;
  color: var(--c-gold);
}

.page-about .ab-method__t {
  margin: 8px 0 6px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
}

.page-about .ab-method__d {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--ab-text-dim);
}

@media (min-width: 700px) {
  .page-about .ab-method {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 新旧对照切片 ---------- */
.page-about .ab-split {
  display: grid;
  gap: 12px;
  margin: clamp(22px, 3.6vw, 40px) 0 0;
}

.page-about .ab-split__pane {
  padding: 18px 18px 20px;
  border: 1px solid var(--ab-line);
  background: rgba(11, 17, 16, .58);
}

.page-about .ab-split__pane--old {
  border-color: rgba(184, 92, 72, .42);
}

.page-about .ab-split__tag {
  display: inline-block;
  padding: 3px 9px 4px;
  border: 1px solid var(--c-gold);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  color: var(--c-gold);
}

.page-about .ab-split__tag--old {
  border-color: var(--c-clay);
  color: var(--c-clay);
}

.page-about .ab-split__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
}

.page-about .ab-split__list {
  list-style: none;
  margin: 12px 0 0;
  padding: 0;
  display: grid;
  gap: 9px;
}

.page-about .ab-split__list li {
  position: relative;
  padding-left: 14px;
  font-size: 13.5px;
  line-height: 1.72;
  color: var(--ab-text-dim);
}

.page-about .ab-split__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .68em;
  width: 6px;
  height: 1px;
  background: var(--c-gold);
}

.page-about .ab-split__pane--old .ab-split__list li::before {
  background: var(--c-clay);
}

@media (min-width: 760px) {
  .page-about .ab-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 0;
  }

  .page-about .ab-split__pane--old {
    padding-right: 42px;
    margin-right: -12px;
    clip-path: polygon(0 0, 100% 0, calc(100% - 26px) 100%, 0 100%);
  }

  .page-about .ab-split__pane--now {
    padding-left: 34px;
  }
}

/* ---------- 订阅节点 ---------- */
.page-about .ab-nodes {
  list-style: none;
  margin: clamp(20px, 3vw, 30px) 0 0;
  padding: 0;
  border-left: 1px solid var(--ab-line);
}

.page-about .ab-node {
  position: relative;
  padding: 0 0 24px 22px;
}

.page-about .ab-node:last-child {
  padding-bottom: 0;
}

.page-about .ab-node::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 5px;
  width: 9px;
  height: 9px;
  background: var(--c-dusk);
  border: 1px solid var(--c-gold);
}

.page-about .ab-node__year {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--c-gold);
}

.page-about .ab-node__title {
  margin: 5px 0 6px;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
}

.page-about .ab-node__text {
  margin: 0;
  max-width: 58ch;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ab-text-soft);
}

.page-about .ab-stat {
  display: block;
  margin: clamp(18px, 2.8vw, 26px) 0 0;
  padding: 16px 18px 18px;
  border-left: 3px solid var(--c-gold);
  background: linear-gradient(90deg, rgba(216, 169, 75, .13), rgba(216, 169, 75, 0) 72%);
}

.page-about .ab-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(30px, 4.6vw, 44px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--c-gold);
}

.page-about .ab-stat__note {
  display: block;
  margin-top: 9px;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--ab-text-dim);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  list-style: none;
  margin: clamp(18px, 2.8vw, 28px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ab-line-soft);
}

.page-about .ab-team__item {
  padding: 15px 16px 17px;
  background: rgba(20, 46, 39, .5);
}

.page-about .ab-team__num {
  font-family: var(--font-mono);
  font-size: 24px;
  line-height: 1;
  color: var(--c-paper);
}

.page-about .ab-team__label {
  display: block;
  margin-top: 7px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--ab-text-dim);
}

@media (min-width: 700px) {
  .page-about .ab-team {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 折叠面板 ---------- */
.page-about .ab-faq {
  margin: clamp(20px, 3vw, 30px) 0 0;
  border-top: 1px solid var(--ab-line);
}

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

.page-about .ab-faq__summary {
  position: relative;
  padding: 14px 30px 14px 0;
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 600;
  color: var(--c-paper);
}

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

.page-about .ab-faq__summary::after {
  content: "+";
  position: absolute;
  right: 4px;
  top: 12px;
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--c-gold);
}

.page-about .ab-faq__item[open] .ab-faq__summary::after {
  content: "–";
}

.page-about .ab-faq__body {
  padding: 0 0 16px;
}

.page-about .ab-faq__body p {
  margin: 0;
  max-width: 62ch;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ab-text-soft);
}

/* ---------- 维护节奏 ---------- */
.page-about .ab-cadence {
  list-style: none;
  margin: clamp(20px, 3.2vw, 32px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ab-line-soft);
}

.page-about .ab-cadence__row {
  padding: 17px 18px 19px;
  background: rgba(20, 46, 39, .55);
}

.page-about .ab-cadence__k {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--c-gold);
}

.page-about .ab-cadence__t {
  margin: 9px 0 8px;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
}

.page-about .ab-cadence__d {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.74;
  color: var(--ab-text-dim);
}

.page-about .ab-cadence + .ab-stage__text {
  margin-top: clamp(18px, 2.8vw, 26px);
}

@media (min-width: 760px) {
  .page-about .ab-cadence {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

/* ---------- 服务承诺（浅底区） ---------- */
.page-about .ab-commit {
  margin-top: clamp(28px, 4.5vw, 60px);
  padding: clamp(30px, 4.6vw, 60px) 0;
  background: var(--c-paper-2);
  color: var(--c-ink);
}

.page-about .ab-commit__eyebrow {
  color: var(--c-clay);
}

.page-about .ab-commit__title {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3.4vw, 38px);
  line-height: 1.26;
  color: var(--c-ink);
}

.page-about .ab-commit__grid {
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  margin-top: clamp(20px, 3vw, 30px);
}

.page-about .ab-commit__box p {
  margin: 0 0 1em;
  max-width: 60ch;
  font-size: 15.5px;
  line-height: 1.85;
  color: #26312E;
}

.page-about .ab-commit__list {
  list-style: none;
  margin: 16px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: rgba(11, 17, 16, .12);
}

.page-about .ab-commit__list li {
  position: relative;
  padding: 10px 14px 10px 26px;
  background: rgba(232, 226, 212, .5);
  font-size: 14px;
  line-height: 1.7;
  color: #1E2A27;
}

.page-about .ab-commit__list li::before {
  content: "";
  position: absolute;
  left: 12px;
  top: 17px;
  width: 6px;
  height: 6px;
  background: var(--c-clay);
}

.page-about .ab-commit__contact {
  padding: 18px 18px 20px;
  border: 1px solid rgba(11, 17, 16, .18);
  border-left: 3px solid var(--c-gold);
  background: rgba(245, 240, 230, .7);
}

.page-about .ab-commit__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .18em;
  color: var(--c-zinc);
}

.page-about .ab-commit__value {
  margin: 6px 0 0;
  font-family: var(--font-mono);
  font-size: 15px;
  line-height: 1.6;
  word-break: break-all;
  color: var(--c-ink);
}

.page-about .ab-commit__value + .ab-commit__label {
  margin-top: 18px;
}

.page-about .ab-commit__copy {
  margin-top: 10px;
}

.page-about .ab-commit__note {
  margin: 18px 0 0;
  font-size: 13px;
  line-height: 1.75;
  color: #3A4642;
}

.page-about .ab-commit .ab-inline-link {
  color: #8A422F;
  border-bottom-color: rgba(138, 66, 47, .45);
}

.page-about .ab-commit .ab-inline-link:hover {
  color: var(--c-clay);
  border-bottom-color: var(--c-clay);
}

@media (min-width: 860px) {
  .page-about .ab-commit__grid {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .65fr);
    align-items: start;
  }
}

/* ---------- 收尾 CTA ---------- */
.page-about .ab-cta {
  padding: clamp(28px, 4.4vw, 54px) 0 clamp(36px, 5vw, 64px);
  background: var(--c-table);
  border-top: 1px solid var(--ab-line);
}

.page-about .ab-cta__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(22px, 3.2vw, 34px);
  line-height: 1.3;
  color: var(--c-paper);
}

.page-about .ab-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(18px, 2.6vw, 26px);
}

@media (max-width: 480px) {
  .page-about .ab-cta__links .pj-btn {
    flex: 1 1 100%;
    text-align: center;
  }
}
<<<END>>>