.page-about {
  --ab-rail: 9px;
  --ab-pad: 32px;
  background: var(--ink);
  color: var(--frost);
}

.page-about .crumb {
  padding-top: clamp(20px, 3vw, 34px);
}

/* ---------- 首屏 ---------- */

.page-about .about-hero {
  padding: clamp(26px, 4.4vw, 52px) 0 clamp(34px, 5.4vw, 68px);
}

.page-about .about-hero__title {
  margin: 16px 0 0;
  font-size: var(--fs-96);
  font-weight: 200;
  line-height: 1.02;
  letter-spacing: -0.03em;
  color: var(--frost);
  max-width: 15em;
  text-wrap: balance;
}

.page-about .about-hero__lede {
  margin: clamp(22px, 3vw, 34px) 0 0;
  max-width: 34em;
  font-size: var(--fs-19);
  line-height: 1.75;
  color: var(--silver);
}

.page-about .about-index {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin-top: clamp(28px, 4vw, 46px);
  padding-top: 18px;
  border-top: 1px solid var(--rule);
}

.page-about .about-index a {
  font-size: var(--fs-13);
  letter-spacing: 0.08em;
  color: var(--dim);
  text-decoration: none;
  padding-bottom: 3px;
  border-bottom: 1px solid transparent;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

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

/* ---------- 纵向刻度结构 ---------- */

.page-about .about-flow__inner {
  position: relative;
  padding-top: clamp(20px, 3vw, 36px);
}

.page-about .about-flow__line {
  position: absolute;
  left: var(--ab-rail);
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, transparent, var(--rule) 4%, var(--rule) 95%, transparent);
  pointer-events: none;
}

.page-about .about-chapter {
  position: relative;
  padding-left: var(--ab-pad);
  padding-bottom: clamp(52px, 7vw, 96px);
}

.page-about .about-chapter::before {
  content: "";
  position: absolute;
  left: var(--ab-rail);
  top: 7px;
  width: 9px;
  height: 9px;
  transform: translateX(-50%);
  background: var(--ink);
  border: 1px solid var(--cyan);
}

.page-about .about-chapter:last-of-type {
  padding-bottom: clamp(40px, 5vw, 72px);
}

.page-about .about-chapter__mark {
  display: block;
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: var(--fs-13);
  letter-spacing: 0.14em;
  color: var(--dim);
}

.page-about .about-chapter__title {
  margin: 8px 0 0;
  font-size: var(--fs-38);
  font-weight: 200;
  line-height: 1.16;
  letter-spacing: -0.02em;
  color: var(--frost);
  max-width: 22em;
}

.page-about .about-chapter__content p,
.page-about .about-chapter__para {
  margin: clamp(16px, 2.2vw, 24px) 0 0;
  max-width: 34em;
  font-size: var(--fs-19);
  line-height: 1.75;
  color: var(--silver);
}

.page-about .about-chapter__content a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 255, 0.4);
  transition: border-color 0.2s var(--ease);
}

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

/* ---------- 超大数字 ---------- */

.page-about .about-figure {
  margin: clamp(26px, 3.6vw, 42px) 0 0;
  padding: clamp(18px, 2.6vw, 26px) 0;
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}

.page-about .about-figure__num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(58px, 11vw, 118px);
  font-weight: 700;
  line-height: 0.9;
  letter-spacing: -0.04em;
  color: var(--orange);
}

.page-about .about-figure__cap {
  display: block;
  margin-top: 14px;
  max-width: 30em;
  font-size: var(--fs-13);
  line-height: 1.7;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 阶段切换 ---------- */

.page-about .switcher {
  margin-top: clamp(22px, 3vw, 34px);
}

.page-about .switcher__bar {
  display: flex;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--rule);
}

.page-about .switcher__tab {
  appearance: none;
  background: transparent;
  border: 0;
  border-bottom: 2px solid transparent;
  margin: 0 20px -1px 0;
  padding: 12px 0;
  color: var(--dim);
  font-family: var(--font-sans);
  font-size: var(--fs-15);
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.page-about .switcher__tab:hover {
  color: var(--frost);
}

.page-about .switcher__tab[aria-selected="true"] {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .switcher__tab:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

.page-about .switcher__panel {
  padding-top: clamp(18px, 2.6vw, 28px);
}

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

.page-about .switcher__panel .label {
  color: var(--orange);
}

/* ---------- 图片 ---------- */

.page-about .about-shot {
  margin: clamp(26px, 3.6vw, 42px) 0 0;
}

.page-about .about-shot img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  background: var(--panel);
  border: 1px solid var(--rule);
}

.page-about .about-shot figcaption {
  margin-top: 12px;
  max-width: 40em;
  font-size: var(--fs-12);
  letter-spacing: 0.1em;
  line-height: 1.7;
  color: var(--dim);
}

/* ---------- 团队比例条 ---------- */

.page-about .about-roster {
  list-style: none;
  margin: clamp(24px, 3.4vw, 38px) 0 0;
  padding: 0;
  border-top: 1px solid var(--rule);
}

.page-about .about-roster__item {
  padding: 18px 0;
  border-bottom: 1px solid var(--rule-soft);
}

.page-about .about-roster__item:nth-child(1) { --w: 100%; }
.page-about .about-roster__item:nth-child(2) { --w: 56%; }
.page-about .about-roster__item:nth-child(3) { --w: 69%; }
.page-about .about-roster__item:nth-child(4) { --w: 19%; }

.page-about .about-roster__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
}

.page-about .about-roster__name {
  font-size: var(--fs-19);
  color: var(--frost);
}

.page-about .about-roster__num {
  font-family: var(--font-mono);
  font-size: var(--fs-24);
  font-weight: 700;
  color: var(--cyan);
  letter-spacing: -0.02em;
}

.page-about .about-roster__track {
  display: block;
  height: 4px;
  margin-top: 12px;
  background: rgba(199, 206, 219, 0.12);
}

.page-about .about-roster__bar {
  display: block;
  height: 100%;
  width: var(--w, 0%);
  background: var(--orange);
}

.page-about .about-roster__desc {
  display: block;
  margin-top: 12px;
  max-width: 40em;
  font-size: var(--fs-13);
  line-height: 1.7;
  color: var(--muted);
}

/* ---------- 要点表 ---------- */

.page-about .about-points {
  list-style: none;
  margin: clamp(24px, 3.4vw, 36px) 0 0;
  padding: 0;
  border-top: 1px solid var(--rule);
}

.page-about .about-points li {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 15px 0;
  border-bottom: 1px solid var(--rule-soft);
}

.page-about .about-points__k {
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  color: var(--dim);
}

.page-about .about-points__v {
  font-size: var(--fs-19);
  line-height: 1.6;
  color: var(--frost);
}

/* ---------- 行动按钮 ---------- */

.page-about .about-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: clamp(26px, 3.4vw, 38px) 0 0;
}

/* ---------- 继续浏览 ---------- */

.page-about .about-next {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 34px;
  padding: clamp(24px, 3.4vw, 38px) 0 clamp(46px, 6vw, 84px) var(--ab-pad);
  border-top: 1px solid var(--rule);
}

.page-about .about-next a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: var(--fs-15);
  letter-spacing: 0.06em;
  color: var(--silver);
  text-decoration: none;
  transition: color 0.2s var(--ease);
}

.page-about .about-next a span {
  color: var(--orange);
  transition: transform 0.2s var(--ease);
}

.page-about .about-next a:hover,
.page-about .about-next a:focus-visible {
  color: var(--cyan);
}

.page-about .about-next a:hover span,
.page-about .about-next a:focus-visible span {
  transform: translateX(4px);
}

/* ---------- 断点 ---------- */

@media (min-width: 620px) {
  .page-about .about-points li {
    grid-template-columns: 200px minmax(0, 1fr);
    gap: 24px;
    align-items: baseline;
  }
}

@media (min-width: 900px) {
  .page-about {
    --ab-rail: 104px;
    --ab-pad: 148px;
  }

  .page-about .about-chapter__mark {
    position: absolute;
    left: 0;
    top: 4px;
    width: 84px;
    margin: 0;
    text-align: right;
  }

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

  .page-about .about-chapter__content p,
  .page-about .about-chapter__para {
    max-width: 32em;
  }

  .page-about .about-hero__title {
    max-width: 13em;
  }
}

@media (min-width: 1180px) {
  .page-about .about-chapter__content p,
  .page-about .about-chapter__para {
    max-width: 34em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-index a,
  .page-about .switcher__tab,
  .page-about .about-next a,
  .page-about .about-next a span {
    transition: none;
  }
}