.page-about {
  --era-rail: 150px;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
}

.page-about .era-topbar {
  padding-top: 24px;
}

.page-about .era-hero {
  padding: 18px 0 6px;
}

.page-about .era-hero__inner {
  display: grid;
  gap: 16px;
}

.page-about .era-hero h1 {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.75rem, 5.4vw, 2.75rem);
  line-height: 1.26;
  letter-spacing: 0.02em;
  color: var(--ink);
  max-width: 22ch;
}

.page-about .era-hero .lede {
  max-width: 64ch;
  color: var(--ink-soft);
  line-height: 1.85;
}

.page-about .era-hero__figure {
  margin: 10px 0 0;
}

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

.page-about .figure__media {
  overflow: hidden;
}

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

/* 阶段索引条 */
.page-about .era-nav {
  margin-top: 30px;
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  background: var(--paper-deep);
}

.page-about .era-nav__inner {
  display: grid;
  gap: 10px;
  padding-top: 14px;
  padding-bottom: 14px;
}

.page-about .era-nav__title {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--cinnabar-deep);
}

.page-about .era-nav__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 2px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .era-nav__list::-webkit-scrollbar {
  display: none;
}

.page-about .era-nav__link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid var(--hairline);
  border-radius: var(--r-pill);
  background: var(--paper);
  color: var(--ink-soft);
  font-size: 14px;
  text-decoration: none;
  white-space: nowrap;
  transition: transform var(--t), border-color var(--t), color var(--t), background var(--t);
}

.page-about .era-nav__link:hover {
  transform: translateY(-2px);
  border-color: var(--hairline-strong);
  color: var(--ink);
}

.page-about .era-nav__link.is-current {
  background: var(--cinnabar);
  border-color: var(--cinnabar);
  color: var(--paper);
}

.page-about .era-nav__idx {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--gilt);
}

.page-about .era-nav__link.is-current .era-nav__idx {
  color: var(--gilt-light);
}

/* 时间轴 */
.page-about .timeline {
  margin-top: 6px;
}

.page-about .era {
  display: grid;
  gap: 14px;
  padding: 30px 0;
  border-top: 1px solid var(--hairline);
}

.page-about .timeline > .era:first-child {
  border-top: 0;
}

.page-about .era__rail {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
}

.page-about .era__idx {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--gilt);
}

.page-about .era__year {
  font-size: 20px;
  letter-spacing: 0.08em;
  color: var(--cinnabar);
  font-variant-numeric: tabular-nums;
}

.page-about .era__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid var(--gilt);
  background: var(--paper);
}

.page-about .era__title {
  margin: 0 0 14px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.6vw, 1.7rem);
  line-height: 1.38;
  letter-spacing: 0.01em;
  color: var(--ink);
}

.page-about .era__body .prose p {
  margin: 0 0 14px;
  color: var(--ink-soft);
  line-height: 1.85;
}

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

.page-about .era__body .prose strong {
  color: var(--ink);
  font-weight: 600;
}

.page-about .era-note {
  margin: 22px 0 0;
  padding: 15px 18px;
  border: 1px solid var(--hairline-strong);
  border-left: 3px solid var(--gilt);
  border-radius: var(--r-md);
  background: var(--paper-deep);
  color: var(--ink);
  font-size: 15px;
  line-height: 1.75;
}

.page-about .era-note__label {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--cinnabar-deep);
}

/* 标签体系：文字 + 层级图 */
.page-about .tag-tree {
  display: grid;
  gap: 24px;
  margin-top: 22px;
}

.page-about .tag-tree__figure {
  margin: 0;
  max-width: 340px;
}

.page-about .fold {
  margin-top: 0;
}

.page-about .tag-notes {
  display: grid;
  gap: 10px;
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .tag-notes__item {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.page-about .tag-notes__key {
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--jade);
}

/* 团队角色标签 */
.page-about .tag-list {
  margin: 18px 0 18px;
}

/* 团队插画 */
.page-about .era-figure {
  margin: 22px 0 0;
}

/* 里程碑 */
.page-about .milestones {
  margin: 22px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .milestones__item {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  padding: 16px 0;
  border-bottom: 1px dashed var(--hairline);
}

.page-about .milestones__item:last-child {
  border-bottom: 0;
}

.page-about .milestones__key {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--jade);
  font-variant-numeric: tabular-nums;
}

.page-about .milestones__text {
  color: var(--ink-soft);
  line-height: 1.75;
}

.page-about .milestones__item--start .milestones__key,
.page-about .milestones__item--now .milestones__key {
  color: var(--cinnabar);
}

.page-about .milestones__item--now .milestones__text {
  color: var(--ink);
  font-weight: 500;
}

/* 下一步 */
.page-about .next-steps {
  margin-top: 56px;
  padding: 30px 22px 34px;
  border-radius: var(--r-lg);
  background: var(--night);
  color: var(--on-night);
}

.page-about .next-steps__eyebrow {
  margin: 0;
  font-size: 11px;
  letter-spacing: 0.2em;
  color: var(--gilt);
}

.page-about .next-steps__title {
  margin: 8px 0 0;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.3rem, 3.6vw, 1.6rem);
  line-height: 1.4;
  color: var(--paper);
}

.page-about .next-steps__grid {
  display: grid;
  gap: 14px;
  margin-top: 24px;
}

.page-about .next-card {
  display: block;
  padding: 18px 20px;
  border: 1px solid var(--hairline-night);
  border-radius: var(--r-md);
  color: var(--on-night);
  text-decoration: none;
  transition: transform var(--t), border-color var(--t), background var(--t);
}

.page-about .next-card:hover {
  transform: translateY(-3px);
  border-color: var(--gilt);
  background: var(--night-soft);
}

.page-about .next-card__label {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-head);
  font-size: 18px;
  color: var(--paper);
}

.page-about .next-card__desc {
  display: block;
  font-size: 14px;
  line-height: 1.7;
  color: var(--on-night-soft);
}

@media (min-width: 48rem) {
  .page-about .next-steps {
    padding: 38px 40px 42px;
  }

  .page-about .next-steps__grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (min-width: 62rem) {
  .page-about .era {
    grid-template-columns: var(--era-rail) minmax(0, 1fr);
    gap: 44px;
    padding: 52px 0;
  }

  .page-about .era__rail {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
    padding-left: 22px;
  }

  .page-about .era__rail::before {
    content: "";
    position: absolute;
    left: 5px;
    top: 6px;
    bottom: 6px;
    width: 2px;
    border-radius: var(--r-pill);
    background: linear-gradient(180deg, var(--hairline-strong), transparent);
  }

  .page-about .era__dot {
    display: none;
  }

  .page-about .era__year {
    font-size: 22px;
  }

  .page-about .tag-tree {
    grid-template-columns: minmax(0, 1fr) 320px;
    gap: 36px;
    align-items: start;
  }

  .page-about .tag-tree__figure {
    max-width: none;
  }

  .page-about .milestones__item {
    grid-template-columns: 96px minmax(0, 1fr);
    gap: 24px;
    padding: 18px 0;
  }

  .page-about .next-steps {
    margin-top: 72px;
  }
}
</PAGE_CSS>>>