.page-about {
  --pb-line: rgba(61, 245, 200, .22);
  --pb-gridline: rgba(61, 245, 200, .055);
  --pb-card: #123B2C;
  background:
    linear-gradient(var(--pb-gridline) 1px, transparent 1px) 0 0 / 100% 32px,
    linear-gradient(90deg, var(--pb-gridline) 1px, transparent 1px) 0 0 / 32px 100%,
    var(--ink);
  color: var(--chalk);
}

/* ---------- 首屏 ---------- */
.pb-hero {
  position: relative;
  padding: 18px 0 42px;
  border-bottom: var(--bd) solid var(--concrete);
}
.pb-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 8px;
  background: repeating-linear-gradient(135deg, var(--neon) 0 10px, transparent 10px 22px);
  opacity: .4;
  pointer-events: none;
}
.pb-hero__grid {
  display: grid;
  gap: 26px;
  margin-top: 20px;
}
.pb-hero__title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.4rem, 8vw, 4.2rem);
  line-height: 1.02;
  letter-spacing: -.02em;
  margin: 10px 0 16px;
}
.pb-hero__title em {
  font-style: normal;
  color: var(--neon);
  display: inline-block;
  transform: skewX(-6deg);
}
.pb-hero__lede {
  max-width: 40ch;
  color: var(--chalk);
  font-size: 1.05rem;
}
.pb-hero__meta {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}
.pb-metaitem {
  border: 2px solid var(--concrete);
  background: var(--turf);
  padding: 10px 12px;
}
.pb-metaitem b {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.5rem;
  line-height: 1.1;
  color: var(--neon);
}
.pb-metaitem span {
  display: block;
  margin-top: 2px;
  font-size: .76rem;
  color: var(--mist);
}
.pb-hero__frame {
  margin: 0;
  padding: 3px;
  background: linear-gradient(140deg, var(--neon), var(--neon-2) 55%, var(--flare));
  clip-path: polygon(0 4%, 100% 0, 100% 96%, 0 100%);
}
.pb-hero__frame img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 28 / 19;
  object-fit: cover;
  clip-path: polygon(0 3%, 100% 0, 100% 97%, 0 100%);
}

/* ---------- 起点 ---------- */
.pb-origin {
  padding-top: 46px;
  padding-bottom: 46px;
}
.pb-origin__grid {
  display: grid;
  gap: 22px;
  margin-top: 22px;
}
.pb-origin__text p {
  margin: 0 0 16px;
}
.pb-note {
  border: var(--bd) solid var(--concrete);
  border-left: 6px solid var(--amber);
  background: var(--turf);
  box-shadow: var(--shadow-sm);
  padding: 20px 18px;
}
.pb-note__quote {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.35rem;
  line-height: 1.4;
  color: var(--amber);
  transform: skewX(-4deg);
}
.pb-note__cap {
  margin: 12px 0 0;
  font-size: .82rem;
  color: var(--mist);
  line-height: 1.7;
}

/* ---------- 时间线 ---------- */
.pb-timeline {
  padding: 44px 0 48px;
  background: linear-gradient(180deg, rgba(27, 74, 56, .55), rgba(8, 19, 15, 0) 70%);
  border-top: var(--bd) solid var(--concrete);
  border-bottom: var(--bd) solid var(--concrete);
}
.pb-timeline__grid {
  display: grid;
  gap: 22px;
  margin-top: 26px;
}
.pb-index__list {
  list-style: none;
  margin: 0 0 6px;
  padding: 0 0 4px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: thin;
}
.pb-index__link {
  display: flex;
  flex-direction: column;
  gap: 3px;
  min-height: 44px;
  padding: 8px 12px;
  border: 2px solid var(--concrete);
  background: var(--turf);
  color: var(--chalk);
  text-decoration: none;
  transition: border-color .2s, transform .2s, background-color .2s;
}
.pb-index__year {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: .9rem;
  color: var(--neon);
  white-space: nowrap;
}
.pb-index__label {
  font-size: .74rem;
  color: var(--mist);
  white-space: nowrap;
}
.pb-index__link:hover,
.pb-index__link:focus-visible {
  border-color: var(--neon);
  background: var(--turf-2);
  transform: translateY(-3px);
  outline: 2px solid var(--neon);
  outline-offset: 2px;
}
.pb-stage {
  border-top: var(--bd) solid var(--concrete);
  padding: 24px 0 28px;
}
.pb-stream > .pb-stage:first-child {
  border-top: 2px dashed var(--pb-line);
}
.pb-stage__year {
  margin: 0;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(1.7rem, 5.5vw, 2.5rem);
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--neon-2);
}
.pb-stage h3 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.3rem;
  margin: 12px 0 8px;
  color: var(--chalk);
}
.pb-stage p {
  margin: 0;
  max-width: 42ch;
  line-height: 1.78;
}
.pb-stage__tags {
  list-style: none;
  margin: 14px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.pb-tag {
  font-family: var(--font-mono);
  font-size: .72rem;
  padding: 4px 9px;
  border: 1px solid var(--pb-line);
  color: var(--neon);
  background: rgba(61, 245, 200, .06);
}
.pb-stage-figure {
  margin: 34px 0 0;
  border: var(--bd) solid var(--concrete);
  background: var(--turf);
  box-shadow: var(--shadow);
  padding: 10px;
}
.pb-stage-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  filter: saturate(.85) contrast(1.06);
}
.pb-stage-figure figcaption {
  margin-top: 10px;
  font-size: .8rem;
  color: var(--mist);
  line-height: 1.7;
}

/* ---------- 团队 ---------- */
.pb-team {
  padding: 46px 0;
}
.pb-formation {
  list-style: none;
  margin: 26px 0 0;
  padding: 20px 14px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
  border: var(--bd) solid var(--concrete);
  background: linear-gradient(180deg, var(--turf), var(--ink));
  position: relative;
}
.pb-formation::before {
  content: "";
  position: absolute;
  inset: 12px;
  border: 1px dashed rgba(61, 245, 200, .22);
  pointer-events: none;
}
.pb-pos {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  background: var(--pb-card);
  border: 2px solid var(--neon-2);
  transition: transform .2s, border-color .2s, box-shadow .2s;
}
.pb-pos:hover,
.pb-pos:focus-visible,
.pb-pos:focus {
  border-color: var(--neon);
  transform: translateY(-3px);
  box-shadow: 4px 4px 0 var(--concrete);
  outline: 2px solid var(--neon);
  outline-offset: 2px;
}
.pb-pos__dot {
  width: 11px;
  height: 11px;
  flex: none;
  background: var(--neon);
  transform: rotate(45deg);
}
.pb-pos__name {
  font-size: .92rem;
  font-weight: 600;
}
.pb-pos__bubble {
  position: absolute;
  left: 0;
  top: calc(100% + 8px);
  z-index: 6;
  width: 100%;
  max-width: 280px;
  padding: 10px 12px;
  background: var(--ink);
  border: 2px solid var(--neon);
  color: var(--chalk);
  font-size: .8rem;
  line-height: 1.65;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity .22s ease, transform .22s ease, visibility .22s;
}
.pb-pos:hover .pb-pos__bubble,
.pb-pos:focus .pb-pos__bubble,
.pb-pos:focus-within .pb-pos__bubble {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.pb-team__stats {
  margin-top: 28px;
}

/* ---------- 流程 ---------- */
.pb-flow {
  padding-bottom: 48px;
}
.pb-flow__line {
  display: none;
  width: 100%;
  height: auto;
}
.pb-flow__path {
  fill: none;
  stroke: var(--neon);
  stroke-width: 3;
  stroke-linejoin: round;
  stroke-dasharray: 1400;
  stroke-dashoffset: 1400;
  animation: pb-draw 2.6s ease-out forwards;
}
@keyframes pb-draw {
  to { stroke-dashoffset: 0; }
}
.pb-flow__steps {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 16px;
  counter-reset: pb-step;
}
.pb-flow__step {
  border: var(--bd) solid var(--concrete);
  background: var(--turf);
  box-shadow: var(--shadow-sm);
  padding: 16px;
  transition: transform .2s, border-color .2s, box-shadow .2s;
}
.pb-flow__step:hover {
  transform: translateY(-4px);
  border-color: var(--neon);
  box-shadow: var(--shadow);
}
.pb-flow__step b {
  display: block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--flare);
  line-height: 1;
}
.pb-flow__step h3 {
  margin: 10px 0 8px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.15rem;
  color: var(--chalk);
}
.pb-flow__step p {
  margin: 0;
  line-height: 1.75;
  font-size: .95rem;
}

/* ---------- 地域 ---------- */
.pb-region {
  padding: 46px 0;
  background: var(--turf-2);
  border-top: var(--bd) solid var(--concrete);
  border-bottom: var(--bd) solid var(--concrete);
}
.pb-region__grid {
  display: grid;
  gap: 26px;
}
.pb-region__text .prose p {
  margin: 0 0 16px;
}
.pb-region__link {
  margin: 18px 0 0;
}
.pb-region__figure {
  margin: 0;
  border: var(--bd) solid var(--concrete);
  background: var(--ink);
  box-shadow: var(--shadow);
  padding: 10px;
}
.pb-region__figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  filter: saturate(.9) contrast(1.05);
}
.pb-region__figure figcaption {
  margin-top: 10px;
  font-size: .8rem;
  color: var(--chalk);
  opacity: .8;
  line-height: 1.7;
}

/* ---------- 开放合作 ---------- */
.pb-open {
  padding-top: 46px;
  padding-bottom: 46px;
}
.pb-open__list {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  gap: 0;
  border-top: 2px dashed var(--pb-line);
}
.pb-open__item {
  padding: 20px 0;
  border-bottom: 2px dashed var(--pb-line);
}
.pb-open__item h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.15rem;
  color: var(--neon);
}
.pb-open__item p {
  margin: 0;
  max-width: 60ch;
  line-height: 1.78;
  font-size: .95rem;
}
.pb-open__cta {
  margin: 26px 0 0;
}

/* ---------- 收尾 ---------- */
.pb-cta {
  background: linear-gradient(120deg, var(--turf-2), var(--ink) 70%);
  border-top: var(--bd) solid var(--concrete);
  padding: 40px 0 52px;
}
.pb-cta__inner {
  display: grid;
  gap: 20px;
}
.pb-cta__inner h2 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.5rem, 4.4vw, 2.2rem);
  line-height: 1.2;
  margin: 0 0 10px;
}
.pb-cta__inner p {
  margin: 0;
  max-width: 46ch;
  line-height: 1.75;
}
.pb-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: flex-start;
}

/* ---------- 触屏与窄屏适配 ---------- */
@media (hover: none) {
  .pb-pos__bubble {
    position: static;
    width: auto;
    max-width: none;
    margin-top: 10px;
    opacity: 1;
    visibility: visible;
    transform: none;
  }
  .pb-pos {
    flex-wrap: wrap;
  }
}

@media (min-width: 900px) {
  .pb-hero {
    padding: 26px 0 56px;
  }
  .pb-hero__grid {
    grid-template-columns: 7fr 5fr;
    align-items: end;
    gap: 44px;
  }
  .pb-hero__meta {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
  .pb-origin__grid {
    grid-template-columns: 7fr 5fr;
    gap: 34px;
    align-items: start;
  }
  .pb-timeline__grid {
    grid-template-columns: 210px minmax(0, 1fr);
    gap: 40px;
    align-items: start;
  }
  .pb-index__list {
    flex-direction: column;
    gap: 10px;
    overflow: visible;
    position: sticky;
    top: 96px;
    padding: 0;
    margin: 0;
  }
  .pb-index__link {
    border-left: 6px solid var(--concrete);
  }
  .pb-index__link:hover,
  .pb-index__link:focus-visible {
    border-left-color: var(--neon);
  }
  .pb-formation {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    padding: 28px 22px;
  }
  .pb-formation > .pb-pos:nth-child(2),
  .pb-formation > .pb-pos:nth-child(4) {
    transform: translateY(14px);
  }
  .pb-formation > .pb-pos:nth-child(2):hover,
  .pb-formation > .pb-pos:nth-child(4):hover,
  .pb-formation > .pb-pos:nth-child(2):focus,
  .pb-formation > .pb-pos:nth-child(4):focus {
    transform: translateY(10px);
  }
  .pb-flow__line {
    display: block;
  }
  .pb-flow__steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
  }
  .pb-region__grid {
    grid-template-columns: 5fr 7fr;
    gap: 40px;
    align-items: center;
  }
  .pb-open__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0 28px;
    border-top: 0;
    border-left: 2px dashed var(--pb-line);
  }
  .pb-open__item {
    padding: 6px 0 6px 22px;
    border-bottom: 0;
    border-right: 2px dashed var(--pb-line);
  }
  .pb-open__item:last-child {
    border-right: 0;
  }
  .pb-cta__inner {
    grid-template-columns: 8fr 4fr;
    align-items: center;
    gap: 34px;
  }
  .pb-cta__actions {
    justify-content: flex-end;
  }
}

@media (prefers-reduced-motion: reduce) {
  .pb-flow__path {
    animation: none;
    stroke-dashoffset: 0;
  }
  .pb-pos,
  .pb-pos__bubble,
  .pb-index__link,
  .pb-flow__step {
    transition: none;
  }
}
</style>