.page-about {
  --about-hair: 2px solid var(--line);
  --about-measure: 62ch;
  --about-soft: rgba(53, 214, 196, .06);
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  overflow-x: hidden;
}

/* 上下文提示 */
.page-about .about-context {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  padding-top: clamp(18px, 3vh, 32px);
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--muted);
}
.page-about .about-context a {
  color: var(--muted);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.page-about .about-context a:hover {
  color: var(--lamp);
  border-bottom-color: var(--lamp);
}

/* 首屏 */
.page-about .about-hero {
  padding: clamp(36px, 6vh, 72px) 0 clamp(64px, 9vh, 120px);
}
.page-about .about-hero__grid {
  display: grid;
  gap: clamp(40px, 6vw, 80px);
  align-items: center;
}
.page-about .about-hero__title {
  margin: 20px 0 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(44px, 8.4vw, 96px);
  line-height: .95;
  letter-spacing: -.015em;
  color: var(--text);
}
.page-about .about-hero__lede {
  margin: 26px 0 0;
  max-width: 30em;
  color: var(--muted);
  font-size: clamp(17px, 1.5vw, 19px);
}
.page-about .about-hero__meta {
  list-style: none;
  margin: 34px 0 0;
  padding: 22px 0 0;
  max-width: 30em;
  border-top: var(--about-hair);
  display: grid;
  gap: 14px;
}
.page-about .about-hero__meta li {
  display: flex;
  gap: 16px;
  align-items: baseline;
}
.page-about .about-hero__num {
  min-width: 132px;
  color: var(--amber);
  font-size: 14px;
}
.page-about .about-hero__meta li span:last-child {
  color: var(--muted);
  font-size: 15px;
}

/* 灯罩与屏幕视觉 */
.page-about .about-stage {
  position: relative;
  aspect-ratio: 5 / 4;
  min-height: 300px;
  border: var(--about-hair);
  box-shadow: var(--shadow);
  background: linear-gradient(165deg, var(--ink-2), var(--ink) 72%);
  overflow: hidden;
}
.page-about .about-stage__halo {
  position: absolute;
  left: 50%;
  top: 5%;
  width: 84%;
  aspect-ratio: 1;
  transform: translateX(-50%);
  background: radial-gradient(circle, rgba(242, 183, 92, .40) 0%, rgba(242, 183, 92, .10) 46%, transparent 72%);
  animation: about-breathe 7s var(--ease) infinite alternate;
}
.page-about .about-stage__cord {
  position: absolute;
  left: 50%;
  top: 0;
  width: 2px;
  height: 13%;
  transform: translateX(-50%);
  background: var(--line);
}
.page-about .about-stage__shade {
  position: absolute;
  left: 50%;
  top: 12%;
  width: 24%;
  height: 18%;
  transform: translateX(-50%);
  background: linear-gradient(180deg, var(--glow), var(--lamp));
  clip-path: polygon(16% 0, 84% 0, 100% 100%, 0 100%);
}
.page-about .about-stage__screen {
  position: absolute;
  left: 9%;
  right: 9%;
  bottom: 9%;
  height: 42%;
  border: var(--about-hair);
  background:
    repeating-linear-gradient(180deg, rgba(53, 214, 196, .16) 0 2px, transparent 2px 6px),
    linear-gradient(180deg, rgba(53, 214, 196, .22), rgba(14, 21, 36, .92) 78%);
}
.page-about .about-stage__screen::after {
  content: "";
  position: absolute;
  left: 12%;
  right: 52%;
  top: 24%;
  height: 4px;
  background: var(--amber);
  opacity: .85;
}
@keyframes about-breathe {
  from { opacity: .72; }
  to { opacity: 1; }
}

/* 章节通用 */
.page-about .about-sec {
  position: relative;
}
.page-about .about-mark {
  display: none;
}
.page-about .about-h2 {
  margin: 18px 0 0;
  font-family: var(--font-body);
  font-weight: 200;
  font-size: clamp(32px, 4.6vw, 64px);
  line-height: 1.06;
  letter-spacing: -.01em;
  color: var(--text);
}
.page-about .about-lede {
  margin: 22px 0 0;
  max-width: var(--about-measure);
  color: var(--muted);
  font-size: 18px;
}
.page-about .frame {
  margin: 0;
}
.page-about .frame__cap {
  font-family: var(--font-data);
  font-size: 12px;
  letter-spacing: .06em;
}

/* 起点 */
.page-about .about-why {
  display: grid;
  gap: clamp(36px, 5vw, 64px);
}
.page-about .about-why__text p {
  margin: 20px 0 0;
  max-width: var(--about-measure);
  color: var(--muted);
}
.page-about .about-why__text p:first-of-type {
  margin-top: 26px;
  color: var(--text);
  font-size: 19px;
}
.page-about .about-why__fig {
  box-shadow: var(--shadow);
}

/* 人群画像带 */
.page-about .about-crowd__row {
  display: grid;
  margin-top: clamp(32px, 4vh, 48px);
  border: var(--about-hair);
  box-shadow: var(--shadow);
  background: var(--ink-2);
}
.page-about .about-crowd__col {
  padding: clamp(24px, 3vw, 38px);
  transition: background .35s var(--ease);
}
.page-about .about-crowd__col + .about-crowd__col {
  border-top: var(--about-hair);
}
.page-about .about-crowd__col:hover {
  background: var(--about-soft);
}
.page-about .about-crowd__idx {
  margin: 0;
  color: var(--screen);
  font-size: 12px;
  letter-spacing: .16em;
}
.page-about .about-crowd__name {
  margin: 14px 0 0;
  font-size: 22px;
  font-weight: 500;
  line-height: 1.35;
}
.page-about .about-crowd__col p {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 15.5px;
}
.page-about .about-crowd__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}
.page-about .about-crowd__tags li {
  padding: 4px 9px;
  border: 1px solid var(--line);
  font-family: var(--font-data);
  font-size: 12px;
  color: var(--muted);
  transition: color .3s var(--ease), border-color .3s var(--ease);
}
.page-about .about-crowd__col:hover .about-crowd__tags li {
  color: var(--lamp);
  border-color: rgba(242, 183, 92, .5);
}

/* 值守 */
.page-about .about-team__fig {
  margin-top: clamp(32px, 4vh, 48px);
  box-shadow: var(--shadow);
}
.page-about .about-steps {
  list-style: none;
  margin: clamp(36px, 5vh, 56px) 0 0;
  padding: 0;
  border-top: var(--about-hair);
}
.page-about .about-steps li {
  display: grid;
  gap: 8px 32px;
  padding: 26px 0;
  border-bottom: var(--about-hair);
}
.page-about .about-steps__no {
  color: var(--screen);
  font-size: 12px;
  letter-spacing: .14em;
}
.page-about .about-steps li h3 {
  margin: 0;
  font-size: 22px;
  font-weight: 500;
  line-height: 1.3;
}
.page-about .about-steps li p {
  margin: 8px 0 0;
  max-width: 54ch;
  color: var(--muted);
  font-size: 16px;
}

/* 版本时间轴 */
.page-about .about-tl__rail {
  position: relative;
  list-style: none;
  margin: clamp(36px, 5vh, 56px) 0 0;
  padding: 0;
  display: grid;
  gap: 34px;
}
.page-about .about-tl__node {
  position: relative;
  padding-left: 46px;
}
.page-about .about-tl__orb {
  position: absolute;
  left: 0;
  top: 2px;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: radial-gradient(circle at 50% 42%, var(--glow), var(--lamp) 46%, rgba(242, 183, 92, .12) 74%);
  box-shadow: 0 0 26px rgba(242, 183, 92, .32);
  transition: box-shadow .3s var(--ease);
}
.page-about .about-tl__ver {
  margin: 0;
  color: var(--amber);
  font-size: 14px;
  letter-spacing: .1em;
}
.page-about .about-tl__node h3 {
  margin: 8px 0 0;
  font-size: 21px;
  font-weight: 500;
  line-height: 1.3;
}
.page-about .about-tl__desc {
  margin: 10px 0 0;
  max-width: 42ch;
  color: var(--muted);
  font-size: 16px;
}
.page-about .about-tl__more {
  margin: 12px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--line);
  color: var(--muted);
  font-size: 15px;
}

/* 合作与专题 */
.page-about .about-topics__grid {
  display: grid;
  gap: clamp(36px, 5vw, 64px);
}
.page-about .about-topics__list {
  list-style: none;
  margin: clamp(28px, 4vh, 40px) 0 0;
  padding: 0;
  display: grid;
  border-top: var(--about-hair);
}
.page-about .about-topics__list li {
  padding: 20px 0;
  border-bottom: var(--about-hair);
}
.page-about .about-topics__no {
  margin: 0;
  color: var(--screen);
  font-size: 12px;
  letter-spacing: .14em;
}
.page-about .about-topics__list h3 {
  margin: 8px 0 0;
  font-size: 19px;
  font-weight: 500;
  line-height: 1.35;
}
.page-about .about-topics__list p {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 15.5px;
}
.page-about .about-topics__fig {
  margin-top: clamp(28px, 4vh, 40px);
  box-shadow: var(--shadow);
}

/* 日常做法 */
.page-about .about-rules {
  list-style: none;
  margin: clamp(32px, 4vh, 48px) 0 0;
  padding: 0;
  border-top: var(--about-hair);
}
.page-about .about-rules__item {
  display: grid;
  gap: 8px 28px;
  padding: 26px 0;
  border-bottom: var(--about-hair);
}
.page-about .about-rules__no {
  color: var(--amber);
  font-size: 13px;
  letter-spacing: .12em;
}
.page-about .about-rules__item h3 {
  margin: 0;
  font-size: 20px;
  font-weight: 500;
  line-height: 1.3;
}
.page-about .about-rules__item p {
  margin: 0;
  max-width: 58ch;
  color: var(--muted);
  font-size: 16px;
}

/* 收尾引导 */
.page-about .about-cta {
  border-top: var(--about-hair);
  background: linear-gradient(180deg, var(--ink-2), var(--ink));
}
.page-about .about-cta__inner {
  padding: clamp(56px, 8vh, 96px) 0;
  display: grid;
  gap: 34px;
  justify-items: start;
}
.page-about .about-cta__links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

/* 中屏与桌面 */
@media (min-width: 760px) {
  .page-about .about-steps li {
    grid-template-columns: 150px minmax(0, 1fr);
  }
  .page-about .about-rules__item {
    grid-template-columns: 78px minmax(0, 1fr);
  }
  .page-about .about-rules__no {
    grid-column: 1;
    grid-row: 1 / span 2;
  }
  .page-about .about-rules__item h3,
  .page-about .about-rules__item p {
    grid-column: 2;
  }
  .page-about .about-topics__list {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    column-gap: 40px;
  }
}

@media (min-width: 880px) {
  .page-about .about-crowd__row {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .page-about .about-crowd__col + .about-crowd__col {
    border-top: 0;
    border-left: var(--about-hair);
  }
}

@media (min-width: 900px) {
  .page-about .about-hero__grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, .95fr);
  }
  .page-about .about-why {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, .85fr);
    align-items: start;
  }
}

@media (min-width: 940px) {
  .page-about .about-tl__rail {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
  }
  .page-about .about-tl__rail::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 13px;
    height: 2px;
    background: var(--line);
  }
  .page-about .about-tl__node {
    padding: 0 26px 0 0;
  }
  .page-about .about-tl__orb {
    position: relative;
    top: 0;
    display: block;
    margin-bottom: 24px;
  }
  .page-about .about-tl__more {
    max-height: 0;
    margin-top: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height .4s var(--ease), opacity .3s var(--ease), margin-top .4s var(--ease);
  }
  .page-about .about-tl__node:hover .about-tl__more,
  .page-about .about-tl__node:focus .about-tl__more,
  .page-about .about-tl__node:focus-within .about-tl__more {
    max-height: 280px;
    margin-top: 12px;
    opacity: 1;
  }
  .page-about .about-tl__node:hover .about-tl__orb,
  .page-about .about-tl__node:focus .about-tl__orb {
    box-shadow: 0 0 38px rgba(242, 183, 92, .62);
  }
}

@media (max-width: 939px) {
  .page-about .about-tl__rail::before {
    content: "";
    position: absolute;
    left: 13px;
    top: 10px;
    bottom: 10px;
    width: 2px;
    background: var(--line);
  }
}

@media (min-width: 980px) {
  .page-about .about-topics__grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr);
    align-items: start;
  }
}

@media (min-width: 1100px) {
  .page-about .about-mark {
    display: block;
    position: absolute;
    left: 12px;
    top: clamp(40px, 6vh, 80px);
    width: 26px;
    height: 26px;
    border-radius: 50%;
    background: radial-gradient(circle at 50% 40%, rgba(247, 239, 226, .95), rgba(242, 183, 92, .6) 42%, rgba(242, 183, 92, 0) 74%);
    box-shadow: 0 0 34px rgba(242, 183, 92, .35);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-stage__halo {
    animation: none;
  }
  .page-about .about-tl__more,
  .page-about .about-tl__orb,
  .page-about .about-crowd__col,
  .page-about .about-crowd__tags li {
    transition: none;
  }
}
<<<END>>>