.page-about {
  --about-gap: clamp(22px, 3.6vw, 44px);
  padding-bottom: clamp(48px, 8vw, 96px);
}

.page-about .about-hero {
  padding-block: clamp(24px, 5vw, 54px) clamp(20px, 3.6vw, 36px);
}

.page-about .about-hero__title {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(34px, 7.2vw, 74px);
  line-height: 1.03;
  letter-spacing: -0.01em;
  color: var(--frost);
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .about-hero__lead {
  margin: 18px 0 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.7vw, 17.5px);
  line-height: 1.9;
  color: var(--mist);
}

/* 横向章节主题带 */
.page-about .about-band {
  display: flex;
  gap: 10px;
  margin-top: clamp(20px, 3vw, 32px);
  padding-top: 14px;
  padding-bottom: 6px;
  border-top: 2px solid var(--grid-line);
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-band__item {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 9px 13px;
  border: 2px solid var(--grid-line);
  background: var(--space-deck);
  color: var(--frost);
  font-size: 13.5px;
  text-decoration: none;
  white-space: nowrap;
  transition: border-color 0.18s ease, color 0.18s ease, transform 0.18s ease;
}

.page-about .about-band__item:hover,
.page-about .about-band__item:focus-visible {
  border-color: var(--cyan);
  color: var(--cyan);
  transform: translateY(-2px);
}

.page-about .about-band__num {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--orange);
  letter-spacing: 0.04em;
}

/* 分屏骨架 */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--about-gap);
  padding-top: clamp(24px, 4vw, 44px);
  border-top: 2px solid var(--grid-line);
}

/* 年份索引 */
.page-about .about-rail {
  border: 2px solid var(--grid-line);
  background: var(--space-deck);
  padding: 16px;
  min-width: 0;
}

.page-about .about-rail__label {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-rail__list {
  display: flex;
  gap: 10px;
  margin: 12px 0 0;
  padding: 0 0 4px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.page-about .about-rail__item {
  flex: 0 0 auto;
}

.page-about .about-rail__item a {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 9px 12px;
  border-left: 3px solid var(--grid-line);
  background: var(--space-deep);
  text-decoration: none;
  transition: border-color 0.18s ease, background 0.18s ease;
}

.page-about .about-rail__item a:hover,
.page-about .about-rail__item a:focus-visible {
  border-left-color: var(--cyan);
  background: var(--space-deck);
}

.page-about .about-rail__year {
  font-family: var(--font-mono);
  font-size: 19px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-rail__note {
  font-size: 12px;
  color: var(--mist);
  white-space: nowrap;
}

.page-about .about-rail__stamp {
  margin: 14px 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--grid-line);
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--mist);
}

.page-about .about-rail__stamp .mono {
  color: var(--orange);
}

/* 章节 */
.page-about .about-chapter {
  margin-bottom: clamp(40px, 6vw, 74px);
  scroll-margin-top: calc(var(--bar-h) + 24px);
}

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

.page-about .about-chapter__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: 14px;
  row-gap: 8px;
  align-items: start;
  padding-top: 12px;
  border-top: 3px solid var(--cyan);
}

.page-about .about-chapter__no {
  font-family: var(--font-mono);
  font-size: clamp(26px, 3.6vw, 38px);
  line-height: 1;
  color: var(--orange);
}

.page-about .about-chapter__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(22px, 4vw, 34px);
  line-height: 1.15;
  color: var(--frost);
}

.page-about .about-chapter__lead {
  grid-column: 1 / -1;
  margin: 0;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .about-text {
  margin: 20px 0 0;
  font-size: 15.5px;
  line-height: 1.9;
  color: var(--mist);
}

.page-about .about-text a {
  color: var(--cyan);
}

/* 年份条目 */
.page-about .about-years {
  display: grid;
  gap: 14px;
  margin: 24px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-year {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  padding: 16px;
  border: 2px solid var(--grid-line);
  background: var(--space-deck);
  scroll-margin-top: calc(var(--bar-h) + 24px);
}

.page-about .about-year__mark {
  font-family: var(--font-mono);
  font-size: 21px;
  line-height: 1.1;
  color: var(--cyan);
}

.page-about .about-year__body h3 {
  margin: 0 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--frost);
}

.page-about .about-year__body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

/* 原则 */
.page-about .about-principles {
  display: grid;
  gap: 18px;
  margin-top: 24px;
}

.page-about .about-principle {
  position: relative;
  padding: 18px 18px 18px 62px;
  border: 2px solid var(--grid-line);
  background: var(--space-deep);
  box-shadow: var(--shadow-soft);
}

.page-about .about-principle__no {
  position: absolute;
  left: 16px;
  top: 17px;
  font-family: var(--font-mono);
  font-size: 24px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-principle h3 {
  margin: 0 0 8px;
  font-size: 17.5px;
  font-weight: 700;
  color: var(--frost);
}

.page-about .about-principle p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-principle__note {
  margin-top: 10px;
  padding-left: 12px;
  border-left: 3px solid var(--sage);
  font-size: 13.5px;
  color: var(--sage);
}

/* 运维三层 */
.page-about .about-layers {
  display: grid;
  gap: 0;
  margin-top: 22px;
}

.page-about .about-layer {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 12px;
  padding: 16px 0;
  border-bottom: 2px solid var(--grid-line);
}

.page-about .about-layer:first-child {
  border-top: 2px solid var(--grid-line);
}

.page-about .about-layer__no {
  font-family: var(--font-mono);
  font-size: 16px;
  line-height: 1.4;
  color: var(--orange);
}

.page-about .about-layer h3 {
  margin: 0 0 6px;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--frost);
}

.page-about .about-layer p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

/* 数据块 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(132px, 1fr));
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-stat {
  padding: 14px;
  border: 2px solid var(--grid-line);
  background: var(--space-deck);
}

.page-about .about-stat__cap {
  margin: 8px 0 0;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--mist);
}

/* 图片 */
.page-about .about-figure {
  margin: 24px 0 0;
}

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

.page-about .about-media-pair {
  margin-top: 24px;
  gap: 16px;
}

.page-about .about-media-pair .about-figure {
  margin-top: 0;
}

/* 团队分组 */
.page-about .about-groups {
  display: grid;
  gap: 12px;
  margin-top: 22px;
}

.page-about .about-group {
  padding: 15px 16px;
  border: 2px solid var(--grid-line);
  background: var(--space-deck);
}

.page-about .about-group h3 {
  margin: 0 0 6px;
  font-size: 16px;
  font-weight: 700;
  color: var(--cyan);
}

.page-about .about-group p {
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

/* 迭代节奏 */
.page-about .about-cycle-wrap {
  margin-top: 22px;
  padding: 16px;
  border: 2px solid var(--grid-line);
  background: var(--space-deep);
}

.page-about .about-cycle__title {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-cycle {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 6px;
}

.page-about .about-cycle span {
  height: 12px;
  border: 2px solid var(--grid-line);
  background: var(--space-deck);
}

.page-about .about-cycle span.is-live {
  border-color: var(--orange);
  background: var(--orange);
}

.page-about .about-cycle__cap {
  margin: 12px 0 0;
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--mist);
}

.page-about .about-cycle__cap .mono {
  color: var(--cyan);
}

/* 评价标签 */
.page-about .about-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .about-chips .tag {
  display: inline-block;
  padding: 5px 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.04em;
  border: 1.5px solid var(--grid-line);
  color: var(--mist);
}

.page-about .about-chips .tag--cyan {
  border-color: var(--cyan);
  color: var(--cyan);
}

.page-about .about-chips .tag--orange {
  border-color: var(--orange);
  color: var(--orange);
}

.page-about .about-chips .tag--sage {
  border-color: var(--sage);
  color: var(--sage);
}

/* 收束 */
.page-about .about-closing {
  margin-top: 24px;
  padding: clamp(18px, 3vw, 28px);
  border: 2px solid var(--cyan);
  background: var(--space-deck);
  box-shadow: var(--shadow-hard);
}

.page-about .about-creed {
  display: grid;
  gap: 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .about-creed li {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  column-gap: 12px;
  row-gap: 6px;
}

.page-about .about-creed__no {
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1.3;
  color: var(--orange);
}

.page-about .about-creed h3 {
  margin: 0;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--frost);
}

.page-about .about-creed p {
  grid-column: 2;
  margin: 0;
  font-size: 15px;
  line-height: 1.85;
  color: var(--mist);
}

.page-about .about-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 22px;
  padding-top: 18px;
  border-top: 2px solid var(--grid-line);
}

/* 平板与桌面 */
@media (min-width: 620px) {
  .page-about .about-year {
    grid-template-columns: 92px minmax(0, 1fr);
    align-items: start;
  }

  .page-about .about-principle:nth-child(2) {
    margin-left: clamp(0px, 1.6vw, 22px);
  }

  .page-about .about-principle:nth-child(3) {
    margin-left: clamp(0px, 3.2vw, 44px);
  }
}

@media (min-width: 900px) {
  .page-about .about-split {
    grid-template-columns: minmax(0, 0.36fr) minmax(0, 0.64fr);
    align-items: start;
  }

  .page-about .about-rail {
    position: sticky;
    top: calc(var(--bar-h) + 20px);
    padding: 20px;
  }

  .page-about .about-rail__list {
    flex-direction: column;
    overflow: visible;
    padding-bottom: 0;
  }

  .page-about .about-rail__item a {
    padding: 10px 14px;
  }

  .page-about .about-principle__note {
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    margin-top: 0;
    transition: max-height 0.28s ease, opacity 0.28s ease, margin-top 0.28s ease;
  }

  .page-about .about-principle:hover .about-principle__note,
  .page-about .about-principle:focus-within .about-principle__note {
    max-height: 220px;
    opacity: 1;
    margin-top: 10px;
  }
}

@media (min-width: 1080px) {
  .page-about .about-stats--wide {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-band__item,
  .page-about .about-rail__item a {
    transition: none;
  }

  .page-about .about-band__item:hover,
  .page-about .about-band__item:focus-visible {
    transform: none;
  }
}
<<<END>>>