.page-about {
  --ab-line: rgba(30, 58, 110, .95);
  --ab-panel: linear-gradient(158deg, rgba(20, 42, 85, .92), rgba(11, 27, 58, .96));
  --ab-cut: 16px;
  color: var(--cloud);
}

.page-about img {
  max-width: 100%;
  height: auto;
}

/* ============ 档案头 ============ */
.page-about .about-hero {
  position: relative;
  padding: 108px 0 0;
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: -180px;
  left: -10%;
  right: -10%;
  height: 640px;
  background:
    radial-gradient(60% 70% at 18% 26%, rgba(52, 224, 224, .16), transparent 70%),
    radial-gradient(52% 62% at 84% 12%, rgba(123, 92, 255, .2), transparent 72%),
    radial-gradient(44% 54% at 62% 86%, rgba(255, 138, 61, .1), transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: 120px;
  right: -120px;
  width: 380px;
  height: 380px;
  background: repeating-linear-gradient(115deg, rgba(52, 224, 224, .16) 0 1px, transparent 1px 15px);
  transform: rotate(10deg);
  opacity: .55;
  pointer-events: none;
  z-index: 0;
}

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

.page-about .breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 24px;
  font-size: .78rem;
  letter-spacing: .1em;
  color: var(--mist);
}

.page-about .breadcrumb a {
  color: var(--mist);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.page-about .breadcrumb a:hover {
  color: var(--cyan);
  border-bottom-color: var(--cyan);
}

.page-about .about-hero__kicker {
  margin: 0 0 18px;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero__title {
  margin: 0 0 22px;
  max-width: 780px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.85rem, 4.6vw, 3.1rem);
  line-height: 1.16;
  letter-spacing: -.01em;
}

.page-about .about-hero__lead {
  margin: 0;
  max-width: 64ch;
  font-size: 1rem;
  line-height: 1.82;
  color: var(--mist);
}

.page-about .ab-stats {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  margin: 36px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-stat {
  padding-left: 16px;
  border-left: 1px solid var(--star);
}

.page-about .ab-stat__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.85rem;
  line-height: 1;
  color: var(--cyan);
}

.page-about .ab-stat__label {
  display: block;
  margin-top: 8px;
  font-size: .8rem;
  letter-spacing: .04em;
  color: var(--mist);
}

.page-about .about-cover {
  margin: 48px 0 0;
}

.page-about .media-frame {
  margin: 0;
}

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

.page-about .about-cover .media-frame__img {
  clip-path: polygon(0 0, calc(100% - 30px) 0, 100% 30px, 100% 100%, 30px 100%, 0 calc(100% - 30px));
}

.page-about .media-frame__caption {
  margin-top: 12px;
  font-size: .78rem;
  line-height: 1.7;
  color: var(--mist);
}

/* ============ 主体骨架 ============ */
.page-about .about-body {
  display: grid;
  gap: 44px;
  padding-top: 64px;
  padding-bottom: 104px;
}

.page-about .about-flow {
  display: grid;
  gap: 72px;
  min-width: 0;
}

/* ============ 左栏档案目录 ============ */
.page-about .about-rail {
  border-top: 2px solid var(--cyan);
  padding-top: 18px;
  min-width: 0;
}

.page-about .about-rail__index {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: .7rem;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--mist);
}

.page-about .about-rail__index span {
  color: var(--orange);
}

.page-about .about-rail__title {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: .06em;
}

.page-about .about-rail__list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-about .index-link {
  display: inline-block;
  padding: 6px 12px;
  font-size: .8rem;
  letter-spacing: .08em;
  color: var(--mist);
  text-decoration: none;
  border: 1px solid var(--star);
  border-radius: 999px;
  background: rgba(20, 42, 85, .5);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .index-link:hover {
  color: var(--cloud);
  border-color: var(--cyan);
  transform: translateY(-2px);
}

.page-about .index-link.is-active {
  color: var(--night);
  background: var(--cyan);
  border-color: var(--cyan);
}

/* ============ 章节头 ============ */
.page-about .ab-sec {
  min-width: 0;
}

.page-about .ab-sec__head {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding-bottom: 16px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--ab-line);
}

.page-about .ab-sec__head::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 64px;
  height: 2px;
  background: var(--cyan);
}

.page-about .ab-sec__num {
  font-family: var(--font-mono);
  font-size: .8rem;
  letter-spacing: .16em;
  color: var(--orange);
}

.page-about .ab-sec__title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.3rem, 2.8vw, 1.85rem);
  line-height: 1.28;
  letter-spacing: -.005em;
}

.page-about .ab-prose {
  margin: 0 0 18px;
  font-size: 1rem;
  line-height: 1.82;
  color: var(--cloud);
}

.page-about .ab-prose--tight {
  margin-top: 26px;
  margin-bottom: 0;
  color: var(--mist);
}

.page-about .ab-inline {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(52, 224, 224, .45);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-about .ab-inline:hover {
  color: var(--cloud);
  border-bottom-color: var(--cloud);
}

/* ============ 卡片 ============ */
.page-about .ab-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  margin-top: 26px;
}

.page-about .ab-card {
  position: relative;
  padding: 22px 20px 24px;
  background: var(--ab-panel);
  border-top: 1px solid rgba(52, 224, 224, .38);
  border-left: 1px solid var(--ab-line);
  clip-path: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 0 100%);
  transition: transform var(--dur) var(--ease), border-top-color var(--dur) var(--ease);
}

.page-about .ab-card:hover {
  transform: translateY(-4px);
  border-top-color: var(--orange);
}

.page-about .ab-card--plain {
  border-top-color: rgba(123, 92, 255, .5);
}

.page-about .ab-card__title {
  margin: 14px 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
  line-height: 1.4;
}

.page-about .ab-card__text {
  margin: 0;
  font-size: .9rem;
  line-height: 1.75;
  color: var(--mist);
}

/* ============ 标签胶囊 ============ */
.page-about .tag {
  display: inline-block;
  padding: 4px 10px;
  font-size: .68rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  border-radius: 999px;
  border: 1px solid rgba(52, 224, 224, .5);
  color: var(--cyan);
  background: rgba(52, 224, 224, .08);
}

.page-about .tag--violet {
  border-color: rgba(123, 92, 255, .55);
  color: var(--lilac);
  background: linear-gradient(120deg, rgba(123, 92, 255, .2), rgba(185, 168, 255, .08));
}

.page-about .tag--orange {
  border-color: rgba(255, 138, 61, .55);
  color: var(--orange);
  background: rgba(255, 138, 61, .1);
}

/* ============ 版本轨迹 ============ */
.page-about .ab-ver {
  position: relative;
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-ver__item {
  position: relative;
  padding-left: 28px;
}

.page-about .ab-ver__item::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 18px;
  bottom: -30px;
  width: 1px;
  background: var(--ab-line);
}

.page-about .ab-ver__item:last-child::before {
  display: none;
}

.page-about .ab-ver__dot {
  position: absolute;
  left: 0;
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--night);
  border: 2px solid var(--cyan);
  box-shadow: 0 0 0 4px rgba(52, 224, 224, .12);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.page-about .ab-ver__ver {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: .92rem;
  letter-spacing: .14em;
  color: var(--cyan);
  transition: color var(--dur) var(--ease);
}

.page-about .ab-ver__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.02rem;
  line-height: 1.42;
}

.page-about .ab-ver__text {
  margin: 0;
  font-size: .88rem;
  line-height: 1.76;
  color: var(--mist);
}

.page-about .ab-ver__text .ab-inline {
  white-space: nowrap;
}

/* ============ 配图 ============ */
.page-about .ab-figure {
  margin: 30px 0 0;
}

.page-about .ab-figure .media-frame__img {
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 24px), calc(100% - 24px) 100%, 0 100%);
}

/* ============ 上架流程 ============ */
.page-about .ab-flow {
  display: grid;
  gap: 0;
  margin-top: 30px;
}

.page-about .ab-flow__svg {
  display: block;
  width: 100%;
  height: auto;
  margin-bottom: 22px;
}

.page-about .ab-flow__list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .ab-flow__step {
  padding: 18px 18px 20px;
  background: rgba(20, 42, 85, .55);
  border-left: 2px solid var(--star);
  transition: border-left-color var(--dur) var(--ease), background var(--dur) var(--ease);
}

.page-about .ab-flow__step:hover {
  border-left-color: var(--cyan);
  background: rgba(20, 42, 85, .9);
}

.page-about .ab-flow__no {
  margin: 0 0 10px;
  font-family: var(--font-mono);
  font-size: .78rem;
  letter-spacing: .18em;
  color: var(--orange);
}

.page-about .ab-flow__title {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1rem;
}

.page-about .ab-flow__text {
  margin: 0;
  font-size: .86rem;
  line-height: 1.74;
  color: var(--mist);
}

/* ============ 按钮 ============ */
.page-about .ab-cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 28px 0 0;
}

.page-about .btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  font-size: .86rem;
  letter-spacing: .08em;
  text-decoration: none;
  border-radius: 2px;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-about .btn--primary {
  background: var(--cyan);
  color: var(--night);
  border: 1px solid var(--cyan);
}

.page-about .btn--ghost {
  background: transparent;
  color: var(--cyan);
  border: 1px solid rgba(52, 224, 224, .5);
}

.page-about .btn:hover {
  transform: translateY(-2px);
}

.page-about .btn--ghost:hover {
  background: rgba(52, 224, 224, .12);
  border-color: var(--cyan);
}

/* ============ 窄屏以上 ============ */
@media (min-width: 620px) {
  .page-about .about-hero {
    padding-top: 124px;
  }

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

  .page-about .ab-cards--3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .page-about .ab-cards--2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .ab-flow__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* ============ 桌面：左栏磁吸目录 ============ */
@media (min-width: 1040px) {
  .page-about .about-hero {
    padding-top: 140px;
  }

  .page-about .about-body {
    grid-template-columns: 236px minmax(0, 1fr);
    gap: 64px;
    padding-top: 80px;
  }

  .page-about .about-rail {
    position: sticky;
    top: 104px;
    align-self: start;
  }

  .page-about .about-rail__list {
    display: block;
  }

  .page-about .index-link {
    position: relative;
    display: block;
    padding: 10px 0 10px 18px;
    border: 0;
    border-radius: 0;
    border-left: 1px solid var(--star);
    background: transparent;
  }

  .page-about .index-link::before {
    content: "";
    position: absolute;
    left: -3px;
    top: 50%;
    width: 5px;
    height: 5px;
    margin-top: -2px;
    background: var(--star);
    transform: rotate(45deg);
    transition: background var(--dur) var(--ease), transform var(--dur) var(--ease);
  }

  .page-about .index-link:hover {
    transform: none;
    color: var(--cloud);
    border-left-color: var(--cyan);
  }

  .page-about .index-link.is-active {
    color: var(--cyan);
    background: transparent;
    border-left-color: var(--cyan);
  }

  .page-about .index-link.is-active::before {
    background: var(--cyan);
    transform: rotate(45deg) scale(1.4);
  }

  .page-about .about-flow {
    gap: 92px;
  }

  .page-about .ab-sec--narrow {
    max-width: 700px;
  }

  .page-about .ab-flow__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .ab-ver {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 22px;
    padding-top: 34px;
  }

  .page-about .ab-ver::before {
    content: "";
    position: absolute;
    top: 12px;
    left: 0;
    right: 0;
    height: 2px;
    background: repeating-linear-gradient(90deg, var(--star) 0 12px, transparent 12px 24px);
  }

  .page-about .ab-ver__item {
    padding-left: 0;
  }

  .page-about .ab-ver__item::before {
    display: none;
  }

  .page-about .ab-ver__dot {
    top: -28px;
  }
}

@media (min-width: 1040px) and (hover: hover) {
  .page-about .ab-ver__item:hover .ab-ver__dot {
    border-color: var(--orange);
    transform: scale(1.25);
    box-shadow: 0 0 0 6px rgba(255, 138, 61, .18);
  }

  .page-about .ab-ver__item:hover .ab-ver__ver {
    color: var(--orange);
  }
}
<<<END>>>