.page-about {
  --about-index-w: 152px;
  --about-card-bg: rgba(16, 31, 60, 0.62);
  background:
    radial-gradient(70% 42% at 88% 0%, rgba(47, 240, 214, 0.09), transparent 68%),
    radial-gradient(60% 40% at 0% 62%, rgba(46, 78, 126, 0.16), transparent 70%),
    linear-gradient(180deg, var(--ink-0) 0%, var(--ink-1) 36%, var(--ink-0) 100%);
  color: var(--white);
  font-family: var(--font-sans);
  padding-bottom: clamp(56px, 8vw, 108px);
}

.page-about .container {
  max-width: 1180px;
  margin-inline: auto;
  padding-inline: clamp(18px, 4.5vw, 40px);
}

/* ---------- 面包屑 ---------- */
.page-about .breadcrumb {
  padding-top: clamp(20px, 4vw, 38px);
  font-size: 13px;
}

.page-about .breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--mist);
}

.page-about .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 8px;
  color: var(--ink-4);
}

.page-about .breadcrumb__item a {
  color: var(--mist);
  text-decoration: none;
  transition: color 0.25s var(--ease);
}

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

.page-about .breadcrumb__item[aria-current="page"] {
  color: var(--white);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  display: grid;
  gap: clamp(26px, 4vw, 44px);
  padding-top: clamp(26px, 4vw, 48px);
  padding-bottom: clamp(40px, 6vw, 76px);
}

.page-about .about-hero__title {
  margin: 14px 0 0;
  font-size: clamp(33px, 6.6vw, 62px);
  line-height: 1.08;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--white);
}

.page-about .about-hero__title em {
  font-style: normal;
  color: var(--cyan);
}

.page-about .about-hero__lead {
  margin: 18px 0 0;
  max-width: 34em;
  color: var(--mist);
  font-size: clamp(15px, 1.7vw, 17px);
  line-height: 1.85;
}

.page-about .about-facts {
  display: grid;
  gap: 14px;
  margin: 26px 0 0;
  padding: 18px 0 0;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-facts__item dt {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .about-facts__item dd {
  margin: 6px 0 0;
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--white);
}

/* ---------- 图框 ---------- */
.page-about .about-figure {
  margin: 0;
  border-radius: var(--radius-l);
  border: 1px solid var(--line-soft);
  overflow: hidden;
  background: var(--ink-2);
  box-shadow: 0 24px 60px rgba(3, 7, 15, 0.55);
}

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

.page-about .about-figure--hero img {
  aspect-ratio: 14 / 9;
}

.page-about .about-figure--flow img {
  aspect-ratio: 3 / 2;
}

.page-about .about-figure--band {
  margin-bottom: clamp(26px, 4vw, 40px);
  border-radius: var(--radius-m);
}

.page-about .about-figure--band img {
  aspect-ratio: 16 / 6;
  opacity: 0.85;
}

/* ---------- 双栏骨架 ---------- */
.page-about .about-body {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
}

.page-about .about-flow {
  min-width: 0;
}

/* ---------- 索引栏 ---------- */
.page-about .about-index__label {
  display: none;
}

.page-about .about-index__list {
  display: flex;
  gap: 8px;
  margin: 0;
  padding: 0 0 6px;
  list-style: none;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .about-index__list::-webkit-scrollbar {
  display: none;
}

.page-about .about-index__link {
  display: block;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--line-soft);
  color: var(--mist);
  font-size: 13px;
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.25s var(--ease), border-color 0.25s var(--ease), background 0.25s var(--ease);
}

.page-about .about-index__link:hover,
.page-about .about-index__link:focus-visible {
  color: var(--white);
  border-color: rgba(47, 240, 214, 0.5);
  background: rgba(12, 42, 46, 0.55);
}

/* ---------- 章节 ---------- */
.page-about .about-section {
  padding-top: clamp(30px, 5vw, 54px);
  scroll-margin-top: 88px;
}

.page-about .about-section + .about-section {
  margin-top: clamp(34px, 5vw, 62px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-section__head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-about .about-section h2 {
  margin: 10px 0 0;
  font-size: clamp(23px, 3.6vw, 36px);
  line-height: 1.24;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-section__intro {
  margin: 14px 0 0;
  max-width: 36em;
  color: var(--mist);
  font-size: 15.5px;
  line-height: 1.85;
}

.page-about .about-section__outro {
  margin: 18px 0 0;
  max-width: 36em;
  color: var(--mist);
  font-size: 15.5px;
  line-height: 1.85;
}

.page-about .about-inline {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(47, 240, 214, 0.4);
  transition: border-color 0.25s var(--ease);
}

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

/* ---------- 小组卡 ---------- */
.page-about .crew-grid {
  display: grid;
  gap: 12px;
}

.page-about .crew-card {
  padding: 18px 20px;
  border-radius: var(--radius-m);
  border: 1px solid var(--line-soft);
  background: linear-gradient(160deg, var(--about-card-bg), rgba(10, 20, 40, 0.62));
  transition: border-color 0.3s var(--ease), background 0.3s var(--ease);
}

.page-about .crew-card:hover {
  border-color: rgba(47, 240, 214, 0.35);
}

.page-about .crew-card[open] {
  border-color: rgba(47, 240, 214, 0.45);
  background: linear-gradient(160deg, rgba(12, 42, 46, 0.9), rgba(10, 20, 40, 0.7));
}

.page-about .crew-card summary {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  list-style: none;
  color: var(--white);
}

.page-about .crew-card summary::-webkit-details-marker {
  display: none;
}

.page-about .crew-card summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--cyan);
}

.page-about .crew-card[open] summary::after {
  content: "−";
}

.page-about .crew-card__icon {
  flex: 0 0 auto;
  color: var(--cyan);
}

.page-about .crew-card__name {
  font-size: 16.5px;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.page-about .crew-card__tag {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .crew-card__list {
  display: grid;
  gap: 10px;
  margin: 14px 0 0;
  padding: 14px 0 0;
  list-style: none;
  border-top: 1px dashed var(--line-soft);
}

.page-about .crew-card__list li {
  position: relative;
  padding-left: 17px;
  color: var(--mist);
  font-size: 14.5px;
  line-height: 1.72;
}

.page-about .crew-card__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px var(--glow-cyan);
}

/* ---------- 流程 ---------- */
.page-about .flow {
  margin: 6px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .flow__step {
  position: relative;
  padding: 0 0 26px 56px;
}

.page-about .flow__step:last-child {
  padding-bottom: 0;
}

.page-about .flow__index {
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-s);
  border: 1px solid var(--line);
  background: var(--ink-2);
  color: var(--cyan);
  font-size: 12px;
  letter-spacing: 0.04em;
}

.page-about .flow__step:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 18px;
  top: 44px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--line), transparent);
}

.page-about .flow__step h3 {
  margin: 2px 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}

.page-about .flow__step p {
  margin: 0;
  max-width: 34em;
  color: var(--mist);
  font-size: 15px;
  line-height: 1.8;
}

.page-about .about-figure--flow {
  margin-top: clamp(24px, 4vw, 36px);
}

/* ---------- 时间轴 ---------- */
.page-about .timeline {
  position: relative;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--ink-3), var(--cyan) 58%, var(--ink-3));
  opacity: 0.65;
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 24px 30px;
}

.page-about .timeline__item:last-child {
  padding-bottom: 0;
}

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--ink-1);
  border: 2px solid var(--ink-4);
  box-sizing: border-box;
}

.page-about .timeline__item--now::before {
  background: var(--cyan);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(47, 240, 214, 0.16), 0 0 14px var(--glow-cyan);
}

.page-about .timeline__year {
  display: block;
  margin-bottom: 6px;
  font-size: 12.5px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-about .timeline__item h3 {
  margin: 0 0 6px;
  font-size: 16.5px;
  font-weight: 700;
  color: var(--white);
}

.page-about .timeline__item p {
  margin: 0;
  max-width: 33em;
  color: var(--mist);
  font-size: 14.5px;
  line-height: 1.8;
}

.page-about .timeline__badge {
  display: inline-block;
  margin-top: 12px;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(255, 122, 47, 0.45);
  color: var(--orange);
  font-size: 11.5px;
  letter-spacing: 0.08em;
}

/* ---------- 笔记选题 ---------- */
.page-about .note-topics {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.page-about .note-topics li {
  padding: 15px 17px;
  border-radius: var(--radius-m);
  border: 1px solid var(--line-soft);
  background: var(--about-card-bg);
  color: var(--mist);
  font-size: 14.5px;
  line-height: 1.72;
}

.page-about .note-topics strong {
  display: block;
  margin-bottom: 5px;
  color: var(--white);
  font-size: 15px;
  font-weight: 700;
}

/* ---------- 收束 ---------- */
.page-about .about-cta {
  margin-top: clamp(42px, 6vw, 76px);
  padding: clamp(24px, 4vw, 46px);
  border-radius: var(--radius-l);
  border: 1px solid var(--line);
  background:
    radial-gradient(85% 130% at 100% 0%, rgba(255, 122, 47, 0.13), transparent 62%),
    radial-gradient(70% 100% at 0% 100%, rgba(47, 240, 214, 0.1), transparent 66%),
    linear-gradient(150deg, var(--ink-2), var(--ink-1));
}

.page-about .about-cta h2 {
  margin: 0 0 12px;
  font-size: clamp(22px, 3.4vw, 32px);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .about-cta p {
  margin: 0;
  max-width: 34em;
  color: var(--mist);
  font-size: 15px;
  line-height: 1.85;
}

.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.page-about .about-cta__actions .btn {
  min-width: 0;
}

/* ---------- 响应式 ---------- */
@media (min-width: 540px) {
  .page-about .about-facts {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
  }
}

@media (min-width: 620px) {
  .page-about .note-topics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
  }
}

@media (min-width: 700px) {
  .page-about .crew-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }
}

@media (min-width: 780px) {
  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.12fr) minmax(0, 1fr);
    align-items: end;
  }

  .page-about .about-figure--hero img {
    aspect-ratio: 4 / 3;
  }
}

@media (min-width: 960px) {
  .page-about .about-body {
    grid-template-columns: var(--about-index-w) minmax(0, 1fr);
    gap: clamp(32px, 4vw, 64px);
  }

  .page-about .about-index {
    position: sticky;
    top: 28px;
    align-self: start;
  }

  .page-about .about-index__label {
    display: block;
    margin: 0 0 16px;
    font-family: var(--font-mono);
    font-size: 10.5px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--ink-4);
  }

  .page-about .about-index__list {
    flex-direction: column;
    gap: 0;
    padding: 0;
    overflow: visible;
  }

  .page-about .about-index__link {
    padding: 10px 0 10px 14px;
    border: 0;
    border-left: 2px solid var(--line-soft);
    border-radius: 0;
    background: none;
    font-family: var(--font-mono);
    font-size: 12px;
    letter-spacing: 0.06em;
    transition: color 0.25s var(--ease), border-color 0.25s var(--ease);
  }

  .page-about .about-index__link:hover,
  .page-about .about-index__link:focus-visible {
    background: none;
    border-left-color: var(--cyan);
  }

  .page-about .about-section {
    padding-top: clamp(10px, 2vw, 18px);
  }

  .page-about .about-section + .about-section {
    margin-top: clamp(44px, 5vw, 70px);
    padding-top: clamp(34px, 4vw, 52px);
  }

  .page-about .about-flow__step p,
  .page-about .flow__step p {
    max-width: 38em;
  }
}

@media (min-width: 1080px) {
  .page-about .about-figure--hero img {
    aspect-ratio: 14 / 9;
  }

  .page-about .about-figure--band img {
    aspect-ratio: 16 / 5;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .crew-card,
  .page-about .about-index__link,
  .page-about .about-inline {
    transition: none;
  }
}
<<<END>>>