.page-about {
  --about-wide: 1320px;
  --about-sec: clamp(62px, 9vw, 128px);
  --about-tl-offset: 60px;
  background: var(--deep);
  color: var(--cloud);
  padding-top: var(--head-h);
  overflow-x: clip;
  scroll-behavior: smooth;
}

.page-about .about-sec {
  scroll-margin-top: calc(var(--head-h) + 24px);
}

.page-about .about-heading {
  color: #fff;
  letter-spacing: -0.01em;
  margin: 10px 0 20px;
  max-width: 26ch;
}

.page-about .about-crumb {
  padding-top: clamp(20px, 3vw, 36px);
}

/* ---------- 章节跳转条 ---------- */
.page-about .about-rail {
  display: none;
}

/* ---------- 开篇 ---------- */
.page-about .about-open {
  padding: clamp(28px, 4vw, 56px) 0 var(--about-sec);
}

.page-about .about-open__grid {
  display: grid;
  gap: clamp(30px, 4.5vw, 64px);
  grid-template-columns: 1fr;
  align-items: end;
}

.page-about .about-open__eyebrow {
  color: var(--cyan-soft);
  letter-spacing: 0.14em;
}

.page-about .about-open__title {
  font-size: clamp(36px, 6.6vw, 78px);
  line-height: 1.05;
  letter-spacing: -0.025em;
  color: #fff;
  margin: 16px 0 22px;
  max-width: 15ch;
}

.page-about .about-open__lede {
  max-width: 52ch;
  font-size: clamp(16px, 1.6vw, 19px);
  line-height: 1.88;
  color: var(--cloud);
}

.page-about .about-open__stats {
  list-style: none;
  margin: 36px 0 0;
  padding: 26px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: clamp(22px, 3.6vw, 48px);
  border-top: 1px solid var(--line-soft);
}

.page-about .about-stat {
  min-width: 92px;
}

.page-about .about-stat__num {
  display: block;
  font-family: var(--mono);
  font-size: clamp(26px, 3.4vw, 40px);
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-stat__label {
  display: block;
  margin-top: 9px;
  font-size: 13px;
  color: var(--cloud);
  opacity: 0.78;
}

.page-about .about-open__media {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 40px 90px -50px rgba(0, 224, 208, 0.55);
}

/* ---------- 为什么坚持秒开 ---------- */
.page-about .about-why {
  padding: var(--about-sec) 0;
}

.page-about .about-why__inner {
  max-width: 780px;
}

.page-about .about-prose p {
  font-size: 17px;
  line-height: 1.92;
  margin: 0 0 1.25em;
}

.page-about .about-prose p:last-child {
  margin-bottom: 0;
}

/* ---------- 时间轴 ---------- */
.page-about .about-line {
  padding: var(--about-sec) 0;
}

.page-about .about-line__head {
  display: grid;
  gap: clamp(26px, 3.6vw, 48px);
  grid-template-columns: 1fr;
  align-items: center;
  margin-bottom: clamp(38px, 5vw, 68px);
}

.page-about .about-line__intro {
  max-width: 46ch;
  font-size: 16px;
  line-height: 1.88;
  margin: 0;
  color: var(--cloud);
  opacity: 0.86;
}

.page-about .about-line__mark {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  max-width: 320px;
}

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

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 21px;
  top: 14px;
  bottom: 26px;
  width: 2px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--cyan) 0%, rgba(0, 224, 208, 0.35) 45%, rgba(127, 243, 234, 0.08) 100%);
}

.page-about .about-tl__item {
  position: relative;
  padding-left: var(--about-tl-offset);
  padding-bottom: clamp(30px, 4.4vw, 58px);
}

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

.page-about .about-tl__mark {
  position: absolute;
  left: 0;
  top: 0;
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--line-strong);
  font-size: 13px;
  color: var(--cyan);
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

.page-about .about-tl__body {
  border-top: 1px solid var(--line-soft);
  padding-top: 18px;
  transition: border-color 0.3s ease;
}

.page-about .about-tl__when {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
  margin: 0 0 10px;
  text-transform: uppercase;
}

.page-about .about-tl__title {
  color: #fff;
  margin: 0 0 12px;
  font-size: clamp(18px, 2vw, 21px);
}

.page-about .about-tl__text {
  margin: 0;
  font-size: 16px;
  line-height: 1.88;
  max-width: 62ch;
}

.page-about .about-tl__note {
  margin: 14px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--line-soft);
  font-size: 14.5px;
  line-height: 1.78;
  color: var(--cyan-soft);
  max-width: 62ch;
  max-height: 3.62em;
  overflow: hidden;
  transition: max-height 0.55s cubic-bezier(0.22, 1, 0.36, 1), border-color 0.3s ease;
}

.page-about .about-tl__item:hover .about-tl__mark,
.page-about .about-tl__item:focus-within .about-tl__mark {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--deep);
}

.page-about .about-tl__item:hover .about-tl__body,
.page-about .about-tl__item:focus-within .about-tl__body {
  border-color: var(--line-strong);
}

.page-about .about-tl__item:hover .about-tl__note,
.page-about .about-tl__item:focus-within .about-tl__note {
  max-height: 12em;
  border-color: var(--cyan);
}

/* ---------- 团队 ---------- */
.page-about .about-team {
  padding: var(--about-sec) 0;
}

.page-about .about-team__grid {
  display: grid;
  gap: clamp(30px, 4.5vw, 64px);
  grid-template-columns: 1fr;
  align-items: start;
}

.page-about .about-team__lede {
  max-width: 48ch;
  font-size: 17px;
  line-height: 1.88;
  margin: 0;
}

.page-about .about-roles {
  list-style: none;
  margin: 30px 0 0;
  padding: 0;
  display: grid;
  gap: 18px;
  grid-template-columns: 1fr;
}

.page-about .about-role {
  padding: 28px 24px 26px;
  border-radius: var(--radius);
  background: rgba(22, 50, 79, 0.72);
  border: 1px solid transparent;
  transition: border-color 0.3s ease, transform 0.3s ease;
}

.page-about .about-role:hover {
  border-color: var(--cyan);
  transform: translateY(-3px);
}

.page-about .about-role__no {
  display: block;
  font-size: 32px;
  line-height: 1;
  color: var(--cyan);
  margin-bottom: 14px;
}

.page-about .about-role .h-card {
  margin: 0 0 10px;
  color: #fff;
}

.page-about .about-role p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.85;
}

.page-about .about-creators {
  padding: clamp(30px, 3.6vw, 44px) clamp(24px, 3vw, 36px);
  border-radius: var(--radius-lg);
  background: linear-gradient(158deg, rgba(0, 224, 208, 0.16) 0%, rgba(245, 197, 107, 0.07) 62%, rgba(8, 24, 47, 0) 100%);
  border: 1px solid var(--line-soft);
}

.page-about .about-creators__num {
  display: block;
  margin: 20px 0 4px;
  font-size: clamp(54px, 7.4vw, 80px);
  line-height: 0.95;
  color: var(--gold);
}

.page-about .about-creators__unit {
  font-size: 0.3em;
  margin-left: 8px;
  color: var(--cloud);
  letter-spacing: 0;
}

.page-about .about-creators__label {
  margin: 0 0 18px;
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--cyan-soft);
}

.page-about .about-creators__text {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--cloud);
}

/* ---------- 内容标准与流程 ---------- */
.page-about .about-flow {
  padding: var(--about-sec) 0;
}

.page-about .about-flow__media {
  margin: 0 0 clamp(34px, 4.6vw, 60px);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.page-about .about-flow__lede {
  max-width: 56ch;
  font-size: 16.5px;
  line-height: 1.88;
  margin: 0;
}

.page-about .about-steps {
  list-style: none;
  margin: clamp(32px, 4.4vw, 52px) 0 0;
  padding: 0;
  display: grid;
  gap: 24px;
  grid-template-columns: 1fr;
}

.page-about .about-step {
  position: relative;
  padding: 22px 4px 0 0;
  border-top: 2px solid var(--line-soft);
  transition: border-color 0.3s ease;
}

.page-about .about-step:hover {
  border-color: var(--cyan);
}

.page-about .about-step__no {
  display: block;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--coral);
  margin-bottom: 12px;
}

.page-about .about-step .h-card {
  margin: 0 0 10px;
  color: #fff;
}

.page-about .about-step p {
  margin: 0;
  font-size: 15.5px;
  line-height: 1.85;
}

.page-about .about-tagrow {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: clamp(32px, 4vw, 48px);
  padding-top: 26px;
  border-top: 1px solid var(--line-soft);
}

/* ---------- 服务范围 ---------- */
.page-about .about-reach {
  padding: var(--about-sec) 0;
}

.page-about .about-reach__grid {
  display: grid;
  gap: clamp(30px, 4.4vw, 62px);
  grid-template-columns: 1fr;
  align-items: center;
}

.page-about .about-reach__copy p {
  margin: 0 0 1.1em;
  font-size: 16.5px;
  line-height: 1.9;
  max-width: 46ch;
}

.page-about .about-reach__copy p:last-child {
  margin-bottom: 0;
}

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

.page-about .about-reach__item {
  padding: 22px 0 20px;
  border-top: 1px solid var(--line-soft);
}

.page-about .about-reach__num {
  margin: 0;
  font-family: var(--mono);
  font-size: clamp(30px, 4.2vw, 46px);
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
}

.page-about .about-reach__num--word {
  font-family: var(--serif);
  font-weight: 700;
  color: var(--gold);
  letter-spacing: 0.06em;
}

.page-about .about-reach__unit {
  font-size: 0.42em;
  margin-left: 6px;
  color: var(--cloud);
  letter-spacing: 0;
}

.page-about .about-reach__label {
  margin: 10px 0 0;
  font-size: 14px;
  color: var(--cloud);
  opacity: 0.8;
}

.page-about .about-reach__bar {
  margin-top: 14px;
}

.page-about .about-reach__item--mobile .data-bar__fill {
  width: 63%;
}

/* ---------- 收束 ---------- */
.page-about .about-next {
  padding: var(--about-sec) 0 calc(var(--about-sec) * 0.7);
}

.page-about .about-next__inner {
  max-width: 900px;
}

.page-about .about-next__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(20px, 3vw, 34px);
  grid-template-columns: 1fr;
}

.page-about .about-next__list > li {
  padding-left: 20px;
  border-left: 2px solid var(--line-soft);
  transition: border-color 0.3s ease;
}

.page-about .about-next__list > li:hover {
  border-color: var(--coral);
}

.page-about .about-next__list .h-card {
  margin: 0 0 10px;
  color: #fff;
}

.page-about .about-next__list p {
  margin: 0;
  font-size: 16px;
  line-height: 1.85;
  max-width: 58ch;
}

.page-about .about-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: clamp(34px, 4.4vw, 52px);
  padding-top: 28px;
  border-top: 1px solid var(--line-soft);
}

/* ---------- 响应式 ---------- */
@media (min-width: 620px) {
  .page-about .about-roles {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-about .about-reach__list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px 28px;
  }

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

@media (min-width: 760px) {
  .page-about {
    --about-tl-offset: 94px;
  }

  .page-about .about-timeline::before {
    left: 31px;
  }

  .page-about .about-tl__mark {
    width: 62px;
    height: 62px;
    font-size: 16px;
  }

  .page-about .about-line__head {
    grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
    align-items: center;
  }

  .page-about .about-line__mark {
    justify-self: end;
    width: 100%;
  }

  .page-about .about-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 26px 30px;
  }
}

@media (min-width: 900px) {
  .page-about .about-open__grid {
    grid-template-columns: minmax(0, 1.06fr) minmax(0, 0.94fr);
  }

  .page-about .about-open__media {
    align-self: start;
    margin-top: clamp(0px, 2vw, 22px);
  }

  .page-about .about-why__inner {
    margin-left: clamp(0px, 6vw, 92px);
  }

  .page-about .about-team__grid {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.6fr);
  }

  .page-about .about-reach__grid {
    grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  }

  .page-about .about-next__inner {
    margin-left: clamp(0px, 4vw, 64px);
  }
}

@media (min-width: 1080px) {
  .page-about .about-steps {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0;
  }

  .page-about .about-step {
    padding: 24px 26px 0 0;
  }

  .page-about .about-step + .about-step {
    padding-left: 26px;
  }

  .page-about .about-step + .about-step::before {
    content: "";
    position: absolute;
    left: 0;
    top: 24px;
    bottom: 0;
    width: 1px;
    background: var(--line-soft);
  }
}

@media (min-width: 1160px) {
  .page-about .about-open__stats {
    gap: clamp(30px, 4vw, 60px);
  }

  .page-about .about-line__head {
    grid-template-columns: minmax(0, 1fr) minmax(0, 340px);
  }
}

@media (min-width: 1680px) {
  .page-about .about-rail {
    display: block;
    position: fixed;
    left: calc((100vw - var(--about-wide)) / 2 - 176px);
    top: 50%;
    transform: translateY(-50%);
    width: 152px;
    z-index: 20;
  }

  .page-about .about-rail__list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 4px;
  }

  .page-about .about-rail__link {
    display: flex;
    align-items: baseline;
    gap: 10px;
    padding: 7px 0 7px 12px;
    border-left: 2px solid transparent;
    font-size: 13px;
    line-height: 1.4;
    color: rgba(201, 214, 228, 0.58);
    text-decoration: none;
    transition: color 0.25s ease, border-color 0.25s ease;
  }

  .page-about .about-rail__link .num {
    font-family: var(--mono);
    font-size: 10.5px;
    letter-spacing: 0.08em;
    color: var(--gold);
    opacity: 0.85;
  }

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

@media (prefers-reduced-motion: reduce) {
  .page-about .about-tl__note,
  .page-about .about-role,
  .page-about .about-tl__mark,
  .page-about .about-step {
    transition: none;
  }
}