.page-about {
  --ab-gap: clamp(48px, 7.5vw, 92px);
  --ab-rail: clamp(92px, 15vw, 172px);
  padding-bottom: clamp(72px, 10vw, 140px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  padding-top: clamp(24px, 5vw, 56px);
}

.page-about .about-hero .breadcrumb {
  margin-bottom: clamp(28px, 5vw, 56px);
}

.page-about .about-hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 4vw, 44px);
  align-items: start;
}

.page-about .about-hero__scope {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  padding-left: 14px;
  border-left: 2px solid rgba(56, 240, 216, .55);
}

.page-about .about-hero__code,
.page-about .about-hero__ver,
.page-about .about-hero__since {
  font-size: .76rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  white-space: nowrap;
}

.page-about .about-hero__code { color: var(--cyan); }
.page-about .about-hero__ver { color: var(--gold); }
.page-about .about-hero__since { color: rgba(242, 237, 228, .5); }

.page-about .about-hero__body h1 {
  font-size: clamp(2.05rem, 5.2vw, 3.6rem);
  line-height: 1.16;
  letter-spacing: -.02em;
  font-weight: 900;
  margin: .35em 0 0;
  max-width: 18em;
}

.page-about .about-hero__body .lede {
  margin-top: clamp(20px, 3vw, 32px);
  max-width: 32em;
  color: rgba(242, 237, 228, .78);
  line-height: 1.95;
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 76px);
  }
  .page-about .about-hero__scope {
    flex-direction: column;
    flex-wrap: nowrap;
    gap: 16px;
    padding-left: 0;
    border-left: 0;
    border-top: 1px solid var(--line-soft);
    padding-top: 18px;
  }
}

/* ---------- 主轴时间线 ---------- */
.page-about .about-spine {
  list-style: none;
  margin: clamp(56px, 8vw, 104px) auto 0;
  padding: 0;
  width: min(var(--wrap), 100% - 2 * var(--gutter));
  display: grid;
  gap: var(--ab-gap);
}

.page-about .about-node {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(14px, 2.6vw, 24px);
}

.page-about .about-node__rail {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 14px;
}

.page-about .about-node__code {
  font-size: .74rem;
  letter-spacing: .2em;
  color: var(--cyan);
}

.page-about .about-node__mark {
  font-size: clamp(1rem, 2.6vw, 1.34rem);
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--paper);
  white-space: nowrap;
}

.page-about .about-node__body > h2 {
  margin: 0 0 .9em;
  font-size: clamp(1.4rem, 3vw, 2.05rem);
  line-height: 1.3;
  letter-spacing: -.015em;
  font-weight: 800;
  max-width: 22em;
}

.page-about .about-node__body > p {
  max-width: 32em;
  margin: 0 0 1.15em;
  line-height: 1.95;
  color: rgba(242, 237, 228, .78);
}

.page-about .about-node__body > p:last-child { margin-bottom: 0; }

.page-about .about-node__body a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(56, 240, 216, .4);
  transition: border-color .2s ease, color .2s ease;
}

.page-about .about-node__body a:hover {
  color: var(--gold);
  border-bottom-color: rgba(232, 183, 92, .6);
}

@media (min-width: 900px) {
  .page-about .about-node {
    grid-template-columns: var(--ab-rail) minmax(0, 1fr);
    gap: clamp(32px, 5vw, 76px);
  }
  .page-about .about-node__rail {
    display: block;
    padding-right: clamp(20px, 3vw, 34px);
  }
  .page-about .about-node__code {
    display: block;
    margin-bottom: 8px;
  }
  .page-about .about-node__mark { display: block; }

  .page-about .about-node__rail::before {
    content: "";
    position: absolute;
    top: 34px;
    bottom: calc(-1 * var(--ab-gap));
    right: 0;
    width: 1px;
    background: linear-gradient(180deg, rgba(56, 240, 216, .5), rgba(74, 85, 104, .22));
  }

  .page-about .about-node:last-child .about-node__rail::before {
    background: linear-gradient(180deg, rgba(56, 240, 216, .5), rgba(56, 240, 216, 0));
    bottom: 0;
  }

  .page-about .about-node__rail::after {
    content: "";
    position: absolute;
    top: 30px;
    right: -4px;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: var(--cyan);
    box-shadow: 0 0 0 5px rgba(56, 240, 216, .12);
  }
}

/* ---------- 配图 ---------- */
.page-about .about-figure {
  margin: clamp(22px, 3.4vw, 36px) 0 0;
}

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
  border: 1px solid var(--line-soft);
  background: var(--ink-2);
  object-fit: cover;
}

.page-about .about-figure__cap {
  display: block;
  margin-top: 10px;
  font-size: .72rem;
  letter-spacing: .12em;
  color: rgba(74, 85, 104, 1);
}

.page-about .about-figure--team img {
  max-width: 34em;
}

/* ---------- 板块索引 ---------- */
.page-about .about-map {
  list-style: none;
  margin: clamp(22px, 3.4vw, 34px) 0 0;
  padding: 1px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.page-about .about-map__item {
  background: var(--ink-2);
  padding: 14px 16px 15px;
  display: grid;
  gap: 5px;
  transition: background .2s ease;
}

.page-about .about-map__item:hover {
  background: var(--panel);
}

.page-about .about-map__code {
  font-size: .74rem;
  letter-spacing: .16em;
  color: var(--cyan);
}

.page-about .about-map__name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--paper);
  letter-spacing: -.005em;
}

.page-about .about-map__meta {
  font-size: .7rem;
  letter-spacing: .04em;
  color: rgba(242, 237, 228, .42);
}

@media (min-width: 640px) {
  .page-about .about-map { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

/* ---------- 版本节奏 ---------- */
.page-about .about-vers {
  list-style: none;
  margin: clamp(22px, 3.4vw, 34px) 0 clamp(22px, 3.4vw, 34px);
  padding: 0;
  display: grid;
  gap: 0;
  border-left: 2px solid rgba(95, 125, 106, .75);
  max-width: 34em;
}

.page-about .about-vers__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
  padding: 14px 0 14px 20px;
  position: relative;
  border-bottom: 1px solid var(--line-soft);
}

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

.page-about .about-vers__row::before {
  content: "";
  position: absolute;
  left: -6px;
  top: 21px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--moss);
}

.page-about .about-vers__tag {
  font-size: .78rem;
  letter-spacing: .12em;
  color: var(--moss);
}

.page-about .about-vers__txt {
  font-size: .95rem;
  line-height: 1.75;
  color: rgba(242, 237, 228, .76);
}

.page-about .about-vers__row--now {
  border-left: 0;
}

.page-about .about-vers__row--now::before {
  background: var(--gold);
  box-shadow: 0 0 0 5px rgba(232, 183, 92, .14);
}

.page-about .about-vers__row--now .about-vers__tag { color: var(--gold); }
.page-about .about-vers__row--now .about-vers__txt { color: var(--paper); }

@media (min-width: 620px) {
  .page-about .about-vers__row {
    grid-template-columns: 6.5em minmax(0, 1fr);
    align-items: baseline;
    gap: 18px;
  }
}

/* ---------- 联系信息 ---------- */
.page-about .about-contact {
  margin: clamp(22px, 3.4vw, 34px) 0 clamp(22px, 3.4vw, 34px);
  padding: clamp(18px, 2.6vw, 28px);
  display: grid;
  gap: 14px;
  background: var(--ink-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  max-width: 34em;
}

.page-about .about-contact__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 4px;
}

.page-about .about-contact__row dt {
  font-size: .7rem;
  letter-spacing: .16em;
  color: var(--grey);
  text-transform: uppercase;
}

.page-about .about-contact__row dd {
  margin: 0;
  font-size: .95rem;
  line-height: 1.7;
  color: var(--paper);
  word-break: break-word;
}

@media (min-width: 620px) {
  .page-about .about-contact__row {
    grid-template-columns: 7.5em minmax(0, 1fr);
    align-items: baseline;
    gap: 16px;
  }
}

/* ---------- 降级与可访问性 ---------- */
@media (prefers-reduced-motion: reduce) {
  .page-about .about-map__item,
  .page-about .about-node__body a {
    transition: none;
  }
}

@media (max-width: 380px) {
  .page-about .about-hero__code,
  .page-about .about-hero__ver,
  .page-about .about-hero__since {
    white-space: normal;
  }
  .page-about .about-node__rail {
    flex-wrap: wrap;
    gap: 8px 12px;
  }
  .page-about .about-node__mark {
    font-size: .95rem;
  }
}