.page-about {
  --ab-tilt: -8deg;
  position: relative;
  padding-bottom: clamp(48px, 8vw, 96px);
}

/* ---------- 面包屑 ---------- */
.page-about .ab-crumb-wrap {
  padding-top: clamp(24px, 4vw, 40px);
}

/* ---------- 首屏 ---------- */
.page-about .ab-hero {
  position: relative;
  padding: clamp(36px, 7vw, 88px) 0 clamp(40px, 7vw, 80px);
  overflow: hidden;
}

.page-about .ab-hero::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -18%;
  width: min(720px, 95vw);
  height: min(720px, 95vw);
  background: radial-gradient(circle at 50% 50%,
      rgba(108, 43, 217, .40),
      rgba(184, 242, 60, .10) 54%,
      transparent 72%);
  pointer-events: none;
  z-index: 0;
}

.page-about .ab-hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(32px, 5vw, 64px);
}

.page-about .ab-hero__title {
  margin: 16px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 6.4vw, 78px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--paper);
  max-width: 15ch;
}

.page-about .ab-hero__lead {
  margin: clamp(20px, 3vw, 30px) 0 0;
  max-width: 60ch;
  font-size: clamp(15px, 1.05vw, 17px);
  line-height: 1.82;
  color: rgba(244, 242, 234, .78);
}

.page-about .ab-hero__actions {
  margin-top: clamp(28px, 4vw, 40px);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px 26px;
}

.page-about .ab-hero__more {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--grape-lit);
  text-decoration: none;
  border-bottom: 1px solid rgba(165, 107, 255, .45);
  padding-bottom: 3px;
  transition: color .25s var(--ease), border-color .25s var(--ease);
}

.page-about .ab-hero__more:hover,
.page-about .ab-hero__more:focus-visible {
  color: var(--lime);
  border-color: var(--lime);
}

.page-about .ab-hero__figures {
  margin: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}

.page-about .ab-figure {
  background: linear-gradient(160deg, rgba(23, 18, 56, .94), rgba(10, 14, 31, .94));
  padding: 18px 16px 22px;
}

.page-about .ab-figure dt {
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--stone);
}

.page-about .ab-figure dd {
  margin: 12px 0 0;
  font-family: var(--font-mono);
  font-size: clamp(20px, 2.4vw, 27px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--lime);
}

.page-about .ab-figure:nth-child(2) dd { color: var(--gold); }
.page-about .ab-figure:nth-child(3) dd { color: var(--grape-lit); }
.page-about .ab-figure:nth-child(4) dd { color: var(--clay); }

/* ---------- 起步与重心 ---------- */
.page-about .ab-origin__wrap {
  max-width: 920px;
}

.page-about .ab-origin__title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 3.6vw, 46px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .ab-origin__quote {
  margin: clamp(26px, 4vw, 44px) 0;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(22px, 3.4vw, 42px);
  line-height: 1.2;
  letter-spacing: -0.01em;
  color: var(--grape-lit);
  max-width: 24ch;
}

.page-about .ab-origin__body p {
  color: rgba(244, 242, 234, .76);
}

/* ---------- 团队 ---------- */
.page-about .ab-team {
  position: relative;
  overflow: hidden;
}

.page-about .ab-watermark {
  position: absolute;
  top: -0.06em;
  left: -0.05em;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(160px, 26vw, 340px);
  line-height: 1;
  color: rgba(165, 107, 255, .07);
  pointer-events: none;
  user-select: none;
  z-index: 0;
}

.page-about .ab-team__inner {
  position: relative;
  z-index: 1;
}

.page-about .ab-team__title,
.page-about .ab-flow__title,
.page-about .ab-stages__title,
.page-about .ab-join__title,
.page-about .ab-upkeep__title {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(26px, 3.8vw, 48px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .ab-team__intro,
.page-about .ab-flow__intro,
.page-about .ab-upkeep__intro {
  margin: 16px 0 0;
  max-width: 56ch;
  font-size: 15px;
  line-height: 1.8;
  color: rgba(244, 242, 234, .72);
}

.page-about .ab-team__body {
  margin-top: clamp(28px, 4vw, 48px);
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 48px);
}

.page-about .ab-team__bars {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 10px;
}

.page-about .ab-bar {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: baseline;
  gap: 6px 18px;
  padding: 18px 20px;
  border-left: 2px solid var(--ab-bar-color, var(--grape));
  border-radius: 0 4px 4px 0;
  background: linear-gradient(90deg, rgba(255, 255, 255, .07), rgba(255, 255, 255, .015));
  transition: background .3s var(--ease), transform .3s var(--ease);
}

.page-about .ab-bar:hover {
  background: linear-gradient(90deg, rgba(255, 255, 255, .12), rgba(255, 255, 255, .03));
  transform: translateX(4px);
}

.page-about .ab-bar:nth-child(1) { --ab-bar-color: var(--clay); }
.page-about .ab-bar:nth-child(2) { --ab-bar-color: var(--lime); }
.page-about .ab-bar:nth-child(3) { --ab-bar-color: var(--gold); }
.page-about .ab-bar:nth-child(4) { --ab-bar-color: var(--grape-lit); }

.page-about .ab-bar__idx {
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--stone);
}

.page-about .ab-bar__name {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(17px, 1.6vw, 21px);
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .ab-bar__count {
  font-family: var(--font-mono);
  font-size: clamp(22px, 2.6vw, 30px);
  line-height: 1;
  font-variant-numeric: tabular-nums;
  color: var(--ab-bar-color);
}

.page-about .ab-bar__desc {
  grid-column: 1 / -1;
  margin: 6px 0 0;
  font-size: 14px;
  line-height: 1.72;
  color: rgba(244, 242, 234, .68);
}

.page-about .ab-team__media {
  margin: 0;
}

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

/* ---------- 五道手 ---------- */
.page-about .ab-flow__steps {
  list-style: none;
  margin: clamp(28px, 4vw, 48px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}

.page-about .ab-step {
  position: relative;
  padding: clamp(20px, 2.4vw, 26px);
  background: linear-gradient(180deg, rgba(23, 18, 56, .88), rgba(10, 14, 31, .88));
  transition: background .3s var(--ease);
}

.page-about .ab-step::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--gold), transparent);
  opacity: 0;
  transition: opacity .3s var(--ease);
}

.page-about .ab-step:hover {
  background: linear-gradient(180deg, rgba(108, 43, 217, .26), rgba(10, 14, 31, .88));
}

.page-about .ab-step:hover::after,
.page-about .ab-step:focus-within::after {
  opacity: 1;
}

.page-about .ab-step__no {
  display: block;
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--gold);
}

.page-about .ab-step__name {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(17px, 1.5vw, 20px);
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .ab-step__desc {
  margin: 10px 0 0;
  font-size: 13.5px;
  line-height: 1.72;
  color: rgba(244, 242, 234, .68);
}

/* ---------- 斜向阶段轴 ---------- */
.page-about .ab-stages__media {
  margin: clamp(28px, 4vw, 44px) 0 0;
}

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

.page-about .ab-timeline {
  position: relative;
  list-style: none;
  margin: clamp(40px, 6vw, 76px) 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
}

.page-about .ab-node {
  position: relative;
  z-index: 1;
}

.page-about .ab-node__dot {
  display: block;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--clay);
  box-shadow: 0 0 0 4px rgba(217, 116, 63, .18);
}

.page-about .ab-node:nth-child(2) .ab-node__dot {
  background: var(--grape-lit);
  box-shadow: 0 0 0 4px rgba(165, 107, 255, .18);
}

.page-about .ab-node:nth-child(3) .ab-node__dot {
  background: var(--lime);
  box-shadow: 0 0 0 4px rgba(184, 242, 60, .18);
}

.page-about .ab-node:nth-child(4) .ab-node__dot {
  background: var(--gold);
  box-shadow: 0 0 0 4px rgba(242, 193, 92, .18);
}

.page-about .ab-node__stage {
  display: block;
  margin-top: 14px;
  color: var(--stone);
}

.page-about .ab-node__name {
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(22px, 2.2vw, 30px);
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--paper);
}

.page-about .ab-node__desc {
  margin: 10px 0 0;
  max-width: 32ch;
  font-size: 13.5px;
  line-height: 1.74;
  color: rgba(244, 242, 234, .62);
  transition: color .3s var(--ease);
}

.page-about .ab-node:hover .ab-node__desc,
.page-about .ab-node:focus-within .ab-node__desc {
  color: var(--paper);
}

/* ---------- 内容征集 ---------- */
.page-about .ab-join__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(28px, 4vw, 52px);
}

.page-about .ab-join__media {
  margin: 0;
}

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

.page-about .ab-join__body .prose {
  margin-top: clamp(18px, 2.6vw, 26px);
}

.page-about .ab-join__body .prose p {
  color: rgba(244, 242, 234, .76);
}

.page-about .ab-join__body .prose a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(184, 242, 60, .4);
}

.page-about .ab-join__body .prose a:hover {
  border-color: var(--lime);
}

.page-about .ab-join__steps {
  list-style: none;
  margin: clamp(22px, 3vw, 32px) 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 14px;
}

.page-about .ab-join__steps li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 13px;
  letter-spacing: .04em;
  color: rgba(244, 242, 234, .84);
  background: var(--glass);
}

.page-about .ab-join__steps .mono {
  font-size: 11px;
  color: var(--gold);
}

/* ---------- 长期维护 ---------- */
.page-about .ab-upkeep__list {
  margin-top: clamp(28px, 4vw, 48px);
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

.page-about .ab-upkeep__item {
  padding: 24px 22px 26px;
  border: 1px solid var(--line);
  border-top: 2px solid rgba(165, 107, 255, .5);
  border-radius: 0 0 4px 4px;
  background: linear-gradient(170deg, rgba(23, 18, 56, .82), rgba(10, 14, 31, .72));
}

.page-about .ab-upkeep__item:nth-child(2) {
  border-top-color: rgba(242, 193, 92, .5);
}

.page-about .ab-upkeep__item:nth-child(3) {
  border-top-color: rgba(184, 242, 60, .5);
}

.page-about .ab-upkeep__itemTitle {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(17px, 1.5vw, 20px);
  letter-spacing: -0.01em;
  color: var(--paper);
}

.page-about .ab-upkeep__text {
  margin: 12px 0 0;
  font-size: 14px;
  line-height: 1.78;
  color: rgba(244, 242, 234, .7);
}

.page-about .ab-upkeep__link {
  display: inline-block;
  margin-top: 18px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .06em;
  color: var(--lime);
  text-decoration: none;
}

.page-about .ab-upkeep__link:hover {
  color: var(--gold);
}

/* ---------- 中等屏幕 ---------- */
@media (min-width: 700px) {
  .page-about .ab-flow__steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-flow__steps .ab-step:nth-child(4),
  .page-about .ab-flow__steps .ab-step:nth-child(5) {
    grid-column: span 1;
  }

  .page-about .ab-join__grid {
    grid-template-columns: 5fr 7fr;
    align-items: start;
  }

  .page-about .ab-join__media {
    position: sticky;
    top: calc(var(--cmd-h) + 24px);
  }
}

/* ---------- 宽屏 ---------- */
@media (min-width: 900px) {
  .page-about .ab-hero__grid {
    grid-template-columns: 7fr 5fr;
    align-items: end;
  }

  .page-about .ab-hero__figures {
    margin-bottom: 14px;
  }

  .page-about .ab-team__body {
    grid-template-columns: 8fr 4fr;
    align-items: start;
  }

  .page-about .ab-flow__steps {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .ab-timeline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
    padding-top: 56px;
    padding-bottom: 56px;
  }

  .page-about .ab-timeline::before {
    content: "";
    position: absolute;
    left: 4%;
    right: 4%;
    top: 26px;
    height: 2px;
    background: linear-gradient(90deg, var(--clay), var(--grape-lit) 34%, var(--lime) 68%, var(--gold));
    transform: rotate(8deg);
    transform-origin: 0 50%;
    opacity: .5;
  }

  .page-about .ab-node {
    padding: 0 clamp(10px, 1.4vw, 22px);
  }

  .page-about .ab-node:nth-child(1) { transform: translateY(30px); }
  .page-about .ab-node:nth-child(2) { transform: translateY(10px); }
  .page-about .ab-node:nth-child(3) { transform: translateY(-10px); }
  .page-about .ab-node:nth-child(4) { transform: translateY(-30px); }

  .page-about .ab-upkeep__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
    align-items: start;
  }

  .page-about .ab-upkeep__item:nth-child(2) { margin-top: 38px; }
  .page-about .ab-upkeep__item:nth-child(3) { margin-top: 14px; }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .ab-bar,
  .page-about .ab-step,
  .page-about .ab-node__desc {
    transition: none;
  }

  .page-about .ab-bar:hover {
    transform: none;
  }
}