.page-about {
  --about-rail: 190px;
  --about-hair: 1px solid var(--ink-700);
  overflow-wrap: break-word;
}

.page-about .about-body {
  min-width: 0;
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding: 30px 0 0;
}

.page-about .about-hero .eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--glacier-300);
}

.page-about .about-hero h1 {
  margin: 16px 0 0;
  max-width: 18em;
  font-size: clamp(30px, 6vw, 54px);
  line-height: 1.14;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--text-primary);
}

.page-about .about-hero .lede {
  margin: 18px 0 0;
  max-width: 36em;
  font-size: 17px;
  line-height: 1.75;
  color: var(--text-muted);
}

.page-about .hero-stats {
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--ink-700);
  border: var(--about-hair);
}

.page-about .hero-stats > div {
  background: var(--ink-800);
  padding: 16px 16px 18px;
}

.page-about .hero-stats dt {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.page-about .hero-stats dd {
  margin: 10px 0 0;
  font-size: 30px;
  line-height: 1;
  font-weight: 700;
  color: var(--glacier-500);
}

.page-about .hero-stats dd .unit {
  margin-left: 6px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 400;
  color: var(--text-muted);
}

@media (min-width: 760px) {
  .page-about .hero-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .page-about .hero-stats dd {
    font-size: 38px;
  }
}

/* ---------- 横向主题带 ---------- */
.page-about .band {
  margin-top: 34px;
}

.page-about .band__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 14px;
}

.page-about .band__inner .mono {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold-orange);
}

.page-about .band__inner p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-primary);
}

/* ---------- 外壳与索引 ---------- */
.page-about .about-shell {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  margin-top: 36px;
  padding-bottom: 64px;
}

.page-about .index-rail {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 10px;
  border-bottom: var(--about-hair);
}

.page-about .index-rail__title {
  display: none;
  margin: 0 0 12px;
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--text-muted);
}

.page-about .index-rail__link {
  flex: 0 0 auto;
  padding: 7px 12px;
  border: var(--about-hair);
  background: var(--ink-800);
  color: var(--text-muted);
  font-size: 13px;
  white-space: nowrap;
  text-decoration: none;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.page-about .index-rail__link:hover {
  color: var(--glacier-300);
  border-color: var(--glacier-500);
}

.page-about .index-rail__link[aria-current="true"] {
  color: var(--ink-900);
  background: var(--glacier-500);
  border-color: var(--glacier-500);
}

@media (min-width: 960px) {
  .page-about .about-shell {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    gap: 48px;
  }
  .page-about .index-rail {
    display: block;
    overflow: visible;
    padding: 0 0 0 16px;
    border-bottom: 0;
    border-left: var(--about-hair);
    position: sticky;
    top: 96px;
    align-self: start;
  }
  .page-about .index-rail__title {
    display: block;
  }
  .page-about .index-rail__link {
    display: block;
    padding: 7px 0;
    border: 0;
    background: none;
    font-family: var(--font-mono);
    font-size: 13px;
  }
  .page-about .index-rail__link[aria-current="true"] {
    background: none;
    color: var(--glacier-500);
  }
}

/* ---------- 章节通用 ---------- */
.page-about .about-section {
  min-width: 0;
  margin-bottom: 28px;
  padding: 26px 0 6px;
  border-top: var(--about-hair);
}

.page-about .section-num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--glacier-500);
}

.page-about .about-section h2 {
  margin: 12px 0 0;
  font-size: clamp(22px, 3.4vw, 32px);
  line-height: 1.3;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--text-primary);
}

.page-about .about-section h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--text-primary);
}

.page-about .about-section p {
  margin: 14px 0 0;
  max-width: 38em;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text-muted);
}

.page-about .takeaway {
  margin-top: 20px;
  padding-left: 14px;
  border-left: 2px solid var(--glacier-500);
  font-size: 14px;
  line-height: 1.7;
  color: var(--glacier-300);
}

/* ---------- 线路与档位 ---------- */
.page-about .line-list {
  list-style: none;
  margin: 20px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ink-700);
  border: var(--about-hair);
}

.page-about .line-list li {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 14px;
  align-items: baseline;
  background: var(--ink-800);
  padding: 14px 16px;
}

.page-about .line-code {
  font-size: 18px;
  font-weight: 700;
  color: var(--glacier-500);
}

.page-about .line-list b {
  display: block;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.page-about .line-list p {
  margin: 4px 0 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-muted);
}

.page-about .tier-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
}

.page-about .tier-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 13px;
  background: var(--ink-800);
  border: var(--about-hair);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%);
  font-size: 13px;
  color: var(--text-muted);
}

.page-about .tier-chip b {
  font-size: 13px;
  font-weight: 700;
  color: var(--glacier-300);
}

/* ---------- 季度刻度 ---------- */
.page-about .quarters {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  max-width: 520px;
}

.page-about .quarter {
  position: relative;
  padding-top: 26px;
  text-align: center;
}

.page-about .quarter::before {
  content: "";
  position: absolute;
  top: 8px;
  left: 0;
  right: 0;
  height: 1px;
  background: var(--ink-700);
}

.page-about .quarter:first-child::before {
  left: 50%;
}

.page-about .quarter:last-child::before {
  right: 50%;
}

.page-about .quarter::after {
  content: "";
  position: absolute;
  top: 4px;
  left: 50%;
  width: 9px;
  height: 9px;
  margin-left: -4.5px;
  background: var(--glacier-500);
  transform: rotate(45deg);
}

.page-about .quarter span {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

/* ---------- 校验流程 ---------- */
.page-about .steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin-top: 24px;
}

.page-about .step {
  position: relative;
  background: var(--ink-800);
  border: var(--about-hair);
  padding: 18px 16px 20px;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%);
  transition: border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .step:hover {
  border-color: var(--glacier-500);
  transform: translateY(-2px);
}

.page-about .step__no {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold-orange);
}

.page-about .step h3 {
  margin-top: 12px;
}

.page-about .step p {
  margin: 8px 0 0;
  max-width: none;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-muted);
}

@media (min-width: 800px) {
  .page-about .steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
    background-image: repeating-linear-gradient(115deg, transparent 0 18px, rgba(79, 209, 217, 0.18) 18px 19px);
  }
}

/* ---------- 区域适用 ---------- */
.page-about .region-block {
  position: relative;
  overflow: hidden;
  padding: 0;
  border: var(--about-hair);
  border-top: var(--about-hair);
  background: var(--ink-800);
}

.page-about .region-block__bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.page-about .region-block__bg img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.14;
}

.page-about .region-block__body {
  position: relative;
  padding: 26px 18px 24px;
}

@media (min-width: 760px) {
  .page-about .region-block__body {
    padding: 34px 34px 30px;
  }
  .page-about .region-block__body p {
    max-width: 34em;
  }
}

/* ---------- 时间线 ---------- */
.page-about .tl {
  position: relative;
  margin: 26px 0 0;
  padding-left: 26px;
  border-left: var(--about-hair);
}

.page-about .tl__item {
  position: relative;
  padding-bottom: 14px;
}

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 14px;
  width: 9px;
  height: 9px;
  background: var(--glacier-500);
  transform: rotate(45deg);
}

.page-about .tl__head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: 12px;
  align-items: baseline;
  width: 100%;
  padding: 6px 0;
  background: none;
  border: 0;
  text-align: left;
  color: inherit;
  font: inherit;
  cursor: pointer;
}

.page-about .tl__year {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--glacier-500);
}

.page-about .tl__title {
  font-size: 16px;
  line-height: 1.5;
  color: var(--text-primary);
}

.page-about .tl__icon {
  position: relative;
  align-self: center;
  width: 12px;
  height: 12px;
  transition: transform 0.2s var(--ease);
}

.page-about .tl__icon::before,
.page-about .tl__icon::after {
  content: "";
  position: absolute;
  background: var(--text-muted);
}

.page-about .tl__icon::before {
  left: 0;
  right: 0;
  top: 5px;
  height: 1px;
}

.page-about .tl__icon::after {
  top: 0;
  bottom: 0;
  left: 5px;
  width: 1px;
}

.page-about .tl__head[aria-expanded="true"] .tl__icon {
  transform: rotate(45deg);
}

.page-about .tl__head:hover .tl__title {
  color: var(--glacier-300);
}

.page-about .tl__panel {
  padding: 2px 0 10px;
}

.page-about .tl__panel[hidden] {
  display: none;
}

.page-about .tl__panel p {
  margin: 0;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-muted);
}

/* ---------- 团队分工 ---------- */
.page-about .team-title {
  margin: 32px 0 0;
}

.page-about .team {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin-top: 18px;
  background: var(--ink-700);
  border: var(--about-hair);
}

.page-about .team__cell {
  background: var(--ink-800);
  padding: 16px;
}

.page-about .team__num {
  display: block;
  font-size: 28px;
  font-weight: 700;
  line-height: 1;
  color: var(--glacier-500);
}

.page-about .team__cell p {
  margin: 10px 0 0;
  max-width: none;
  font-size: 13px;
  line-height: 1.65;
  color: var(--text-muted);
}

@media (min-width: 640px) {
  .page-about .team {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .page-about .team {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---------- 链接清单 ---------- */
.page-about .link-list {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--ink-700);
  border: var(--about-hair);
}

.page-about .link-list li {
  display: grid;
  gap: 6px;
  background: var(--ink-800);
  padding: 14px 16px;
}

.page-about .link-list a {
  justify-self: start;
  color: var(--glacier-300);
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.page-about .link-list a:hover {
  color: var(--glacier-500);
  border-bottom-color: var(--glacier-500);
}

.page-about .link-list span {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-muted);
}

/* ---------- 图文框 ---------- */
.page-about .media-frame {
  margin: 22px 0 0;
  border: var(--about-hair);
  background: var(--ink-800);
  overflow: hidden;
}

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

.page-about .media-frame__caption {
  margin: 0;
  padding: 10px 14px;
  max-width: none;
  border-top: var(--about-hair);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

@media (prefers-reduced-motion: reduce) {
  .page-about .step,
  .page-about .tl__icon,
  .page-about .index-rail__link,
  .page-about .link-list a {
    transition: none;
  }
  .page-about .step:hover {
    transform: none;
  }
}
<<<END>>>