/* ============ 品牌价值页 · page-about ============ */

.page-about {
  --about-rail: 200px;
  --about-colgap: clamp(22px, 3vw, 48px);
}

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

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: clamp(24px, 5vw, 60px) 0 clamp(26px, 4vw, 48px);
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  max-width: 17ch;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(32px, 6.4vw, 64px);
  line-height: 1.06;
  letter-spacing: -0.5px;
  color: var(--cold);
}

.page-about .about-hero__lede {
  margin: 20px 0 0;
  max-width: 46ch;
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.75;
  color: rgba(233, 246, 243, 0.82);
}

.page-about .about-hero__actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px 22px;
}

.page-about .about-hero__more {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 2px;
}

.page-about .about-hero__more:hover,
.page-about .about-hero__more:focus-visible {
  color: var(--cold);
  border-bottom-color: var(--cyan);
}

/* ---------- 章节骨架：左编号 + 右内容 ---------- */

.page-about .about-chapter {
  display: grid;
  grid-template-columns: 1fr;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-chapter__rail {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: clamp(26px, 4vw, 46px) 0 0;
}

.page-about .about-chapter__num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.12em;
  color: var(--cyan);
}

.page-about .about-chapter__kicker {
  font-family: var(--font-serif);
  font-size: 14px;
  letter-spacing: 0.3em;
  color: var(--gold);
}

.page-about .about-chapter__body {
  padding: clamp(14px, 2vw, 20px) 0 clamp(38px, 5.5vw, 76px);
  min-width: 0;
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(24px, 3.6vw, 40px);
  line-height: 1.14;
  letter-spacing: -0.2px;
  color: var(--cold);
}

.page-about .about-chapter__intro {
  margin: 16px 0 0;
  max-width: 40ch;
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate);
}

.page-about .about-chapter__cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 38px);
  margin-top: 22px;
}

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

.page-about .prose a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
}

.page-about .prose a:hover,
.page-about .prose a:focus-visible {
  color: var(--cold);
  border-bottom-color: var(--cyan);
}

.page-about .about-prose--wide {
  margin-top: 20px;
  max-width: 62ch;
}

/* ---------- 三步方法 ---------- */

.page-about .about-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 26px;
}

.page-about .step-card {
  align-self: start;
  background: var(--surface);
  border: 1px solid var(--line);
  border-top: 2px solid var(--cyan);
}

.page-about .step-card__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 18px 18px 14px;
  cursor: pointer;
  list-style: none;
}

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

.page-about .step-card__head::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1;
  color: var(--signal);
}

.page-about .step-card[open] .step-card__head::after {
  content: "–";
}

.page-about .step-card__num {
  font-size: 30px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .step-card__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 19px;
  color: var(--cold);
}

.page-about .step-card__text {
  margin: 0;
  padding: 0 18px 16px;
  font-size: 15px;
  line-height: 1.72;
  color: var(--slate);
}

.page-about .step-card__scene {
  margin: 0;
  padding: 14px 18px 18px;
  border-top: 1px solid var(--line-soft);
  font-size: 14px;
  line-height: 1.72;
  color: var(--cold);
}

.page-about .about-steps__figure {
  margin: clamp(26px, 4vw, 44px) 0 0;
}

/* ---------- 团队分工 ---------- */

.page-about .org-chart {
  margin-top: 26px;
}

.page-about .org-chart__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  border: 1px solid var(--line);
  background: var(--line-soft);
}

.page-about .org-chart__node {
  display: grid;
  gap: 8px;
  padding: 22px 18px 24px;
  background: var(--bg);
}

.page-about .org-chart__role {
  font-family: var(--font-serif);
  font-size: 14px;
  letter-spacing: 0.2em;
  color: var(--gold);
}

.page-about .org-chart__count {
  font-size: 38px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .org-chart__duty {
  font-size: 14px;
  line-height: 1.72;
  color: var(--slate);
}

.page-about .about-chapter .aside-note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
}

/* ---------- 版本演进 ---------- */

.page-about .about-timeline {
  list-style: none;
  margin: 28px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
}

.page-about .about-timeline__item {
  position: relative;
  padding: 0 0 26px 24px;
  border-left: 1px solid var(--line);
  outline: none;
}

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

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 5px;
  width: 7px;
  height: 7px;
  background: var(--gold);
  transition: background 0.18s var(--ease);
}

.page-about .about-timeline__item:hover::before,
.page-about .about-timeline__item:focus-visible::before,
.page-about .about-timeline__item:focus-within::before {
  background: var(--signal);
}

.page-about .about-timeline__ver {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 20px;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.page-about .about-timeline__theme {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 17px;
  line-height: 1.3;
  color: var(--cold);
}

.page-about .about-timeline__detail {
  margin: 0;
  max-width: 34ch;
  font-size: 14px;
  line-height: 1.72;
  color: var(--slate);
  opacity: 0.55;
  transition: opacity 0.2s var(--ease);
}

.page-about .about-timeline__item:hover .about-timeline__detail,
.page-about .about-timeline__item:focus-visible .about-timeline__detail,
.page-about .about-timeline__item:focus-within .about-timeline__detail {
  opacity: 1;
}

.page-about .about-timeline-banner {
  margin: clamp(28px, 4vw, 46px) 0 0;
}

/* ---------- 四个理由 ---------- */

.page-about .about-reasons {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--line-soft);
}

.page-about .about-reasons__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: 16px;
  align-items: baseline;
  padding: 24px 20px 26px;
  background: var(--bg);
}

.page-about .about-reasons__num {
  grid-row: 1 / span 2;
  font-size: 14px;
  color: var(--signal);
}

.page-about .about-reasons__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  line-height: 1.3;
  color: var(--cold);
}

.page-about .about-reasons__item p {
  grid-column: 2;
  margin: 0;
  font-size: 15px;
  line-height: 1.72;
  color: var(--slate);
}

.page-about .about-actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 22px;
}

.page-about .about-actions__link {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid var(--line-strong);
  padding-bottom: 2px;
}

.page-about .about-actions__link:hover,
.page-about .about-actions__link:focus-visible {
  color: var(--cold);
  border-bottom-color: var(--cyan);
}

/* ---------- 桌面布局 ---------- */

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

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

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

@media (min-width: 880px) {
  .page-about .about-chapter {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
  }

  .page-about .about-chapter__rail {
    flex-direction: column;
    gap: 12px;
    padding: clamp(34px, 5vw, 62px) 26px clamp(34px, 5vw, 62px) 0;
    border-right: 1px solid var(--line);
  }

  .page-about .about-chapter__body {
    padding: clamp(34px, 5vw, 62px) 0 clamp(34px, 5vw, 62px) var(--about-colgap);
  }
}

@media (min-width: 900px) {
  .page-about .about-timeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .about-timeline__item {
    padding: 30px 22px 0 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

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

  .page-about .about-timeline__item::before {
    left: 0;
    top: -4px;
  }

  .page-about .about-timeline__detail {
    max-width: 30ch;
  }
}

@media (min-width: 1040px) {
  .page-about .about-chapter__cols {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: start;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__detail,
  .page-about .about-timeline__item::before {
    transition: none;
  }
}
<<<END>>>