.page-about {
  --about-line: rgba(213, 219, 226, .9);
  --about-tl-year: 88px;
  --about-gap: 24px;
}

.page-about .about-hero {
  position: relative;
  display: grid;
  gap: 26px;
  padding: 30px 20px 26px;
  margin-top: 16px;
  border-radius: var(--r);
  background-color: var(--c-rock);
  background-image:
    linear-gradient(90deg, rgba(127, 217, 224, .10) 1px, transparent 1px),
    linear-gradient(180deg, rgba(127, 217, 224, .07) 1px, transparent 1px),
    linear-gradient(158deg, var(--c-rock) 0%, var(--c-rock-2) 100%);
  background-size: 72px 72px, 72px 72px, 100% 100%;
  color: var(--c-cream);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--c-cyan) 0%, var(--c-orange) 62%, rgba(255, 122, 47, 0) 100%);
}

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

.page-about .about-hero .eyebrow {
  margin: 0;
  color: var(--c-cyan-soft);
}

.page-about .about-hero .page-title {
  margin: 12px 0 0;
  color: var(--c-cream);
  font-size: clamp(25px, 6.2vw, 42px);
  line-height: 1.26;
  letter-spacing: .04em;
  font-weight: 600;
}

.page-about .about-hero .lede {
  margin: 16px 0 0;
  max-width: 62ch;
  color: rgba(241, 243, 245, .82);
  font-size: 16px;
  line-height: 1.78;
}

.page-about .about-hero__strip {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: rgba(127, 217, 224, .24);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .about-hero__cell {
  padding: 13px 14px;
  background: rgba(11, 33, 55, .78);
}

.page-about .about-hero__cell dt {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--c-cyan-soft);
}

.page-about .about-hero__cell dd {
  margin: 7px 0 0;
  font-family: var(--font-mono);
  font-size: 19px;
  letter-spacing: .02em;
  color: var(--c-cream);
}

/* ---------- 区块节奏 ---------- */
.page-about .about-block {
  margin-top: 56px;
}

.page-about .about-follow {
  margin: 22px 0 0;
}

.page-about .about-follow--end {
  margin-top: 6px;
}

/* ---------- 01 我们是谁 ---------- */
.page-about .about-who {
  margin-top: 22px;
}

.page-about .about-who__side {
  border-left: 2px solid var(--c-cyan);
  padding-left: 16px;
}

.page-about .about-who__label {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--c-muted);
  text-transform: uppercase;
}

.page-about .about-who__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 12px;
}

.page-about .about-who__list li {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-body);
  padding-bottom: 12px;
  border-bottom: 1px solid var(--c-line);
}

.page-about .about-who__list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.page-about .about-who__k {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--c-clay);
  margin-bottom: 3px;
}

/* ---------- 02 时间线 ---------- */
.page-about .about-tl-figure {
  margin: 24px 0 34px;
}

.page-about .tl {
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  position: relative;
}

.page-about .tl::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 10px;
  bottom: 16px;
  width: 1px;
  background: linear-gradient(180deg, var(--c-cyan) 0%, var(--c-cyan-soft) 48%, var(--c-line) 100%);
}

.page-about .tl__item {
  position: relative;
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: 12px;
  padding-bottom: 30px;
}

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

.page-about .tl__item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 7px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--c-mist);
  border: 2px solid var(--c-cyan);
  transition: border-color var(--t-fast), background var(--t-fast);
}

.page-about .tl__item:hover::before {
  border-color: var(--c-orange);
  background: var(--c-cream);
}

.page-about .tl__mark {
  display: flex;
  flex-direction: column;
  gap: 4px;
  outline: none;
  border-radius: var(--r);
}

.page-about .tl__year {
  font-family: var(--font-mono);
  font-size: 17px;
  letter-spacing: .08em;
  color: var(--c-rock);
  transition: color var(--t-fast);
}

.page-about .tl__tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--c-orange);
}

.page-about .tl__mark:focus-visible {
  box-shadow: 0 0 0 2px var(--c-cyan), inset 0 0 0 1px var(--c-orange);
}

.page-about .tl__mark:hover .tl__year,
.page-about .tl__mark:focus-visible .tl__year {
  color: var(--c-orange);
}

.page-about .tl__body {
  display: grid;
  gap: 12px;
  min-width: 0;
}

.page-about .tl__card .panel__note {
  margin-top: 8px;
}

.page-about .tl__aside {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--c-muted);
  border-left: 1px solid var(--c-line);
  padding-left: 12px;
}

/* ---------- 03 团队 ---------- */
.page-about .about-team {
  margin-top: 22px;
}

.page-about .about-team-figure {
  aspect-ratio: 9 / 5.6;
  margin: 0;
}

.page-about .roles {
  margin-top: 22px;
  border-top: 1px solid var(--c-line);
}

.page-about .role {
  border-bottom: 1px solid var(--c-line);
}

.page-about .role__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 4px;
  cursor: pointer;
  list-style: none;
  outline: none;
  transition: background var(--t-fast), padding var(--t-fast);
}

.page-about .role__head::-webkit-details-marker {
  display: none;
}

.page-about .role__head:hover {
  background: rgba(18, 165, 181, .06);
  padding-left: 10px;
}

.page-about .role__head:focus-visible {
  box-shadow: 0 0 0 2px var(--c-cyan), inset 0 0 0 1px var(--c-orange);
}

.page-about .role__name {
  font-size: 16px;
  font-weight: 600;
  color: var(--c-rock);
  letter-spacing: .02em;
}

.page-about .role__num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .08em;
  color: var(--c-cyan);
}

.page-about .role__body {
  margin: 0;
  padding: 0 4px 16px;
  font-size: 15px;
  line-height: 1.78;
  color: var(--c-body);
}

.page-about .role[open] .role__num {
  color: var(--c-orange);
}

/* ---------- 04 资质 ---------- */
.page-about .certs {
  list-style: none;
  margin: 22px 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .certs__item {
  display: grid;
  gap: 6px;
  padding: 18px 18px 16px;
  background: var(--c-cream);
  outline: none;
  transition: background var(--t-fast), box-shadow var(--t-fast);
}

.page-about .certs__item:hover {
  background: #fff;
}

.page-about .certs__item:focus-visible {
  box-shadow: inset 0 0 0 2px var(--c-cyan), inset 0 0 0 3px rgba(255, 122, 47, .55);
  background: #fff;
}

.page-about .certs__idx {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--c-orange);
}

.page-about .certs__val {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.55;
  color: var(--c-rock);
  letter-spacing: .01em;
}

.page-about .certs__note {
  font-size: 14px;
  line-height: 1.7;
  color: var(--c-muted);
}

/* ---------- 05 合作生态 ---------- */
.page-about .about-eco {
  margin-top: 22px;
}

.page-about .about-eco__side {
  display: grid;
  gap: 1px;
  align-content: start;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .about-eco__stat {
  display: grid;
  gap: 6px;
  padding: 16px;
  background: var(--c-rock);
}

.page-about .about-eco__num {
  font-family: var(--font-mono);
  font-size: 26px;
  letter-spacing: .04em;
  color: var(--c-cyan-soft);
}

.page-about .about-eco__label {
  font-size: 13px;
  line-height: 1.6;
  color: rgba(241, 243, 245, .74);
}

/* ---------- 06 覆盖与响应 ---------- */
.page-about .about-cov {
  margin-top: 22px;
}

.page-about .cov {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1px;
  background: var(--c-line);
  border: 1px solid var(--c-line);
  border-radius: var(--r);
  overflow: hidden;
}

.page-about .cov__item {
  display: grid;
  gap: 4px;
  padding: 16px;
  background: var(--c-mist);
}

.page-about .cov__num {
  font-family: var(--font-mono);
  font-size: 28px;
  line-height: 1.1;
  letter-spacing: .03em;
  color: var(--c-rock);
}

.page-about .cov__unit {
  font-size: 13px;
  line-height: 1.6;
  color: var(--c-muted);
}

.page-about .about-cov__text {
  margin-top: 22px;
}

.page-about .about-cov-figure {
  aspect-ratio: 19 / 12;
  margin: 22px 0 0;
}

/* ---------- 图片适配 ---------- */
.page-about img {
  max-width: 100%;
  height: auto;
}

/* ---------- 响应式 ---------- */
@media (min-width: 640px) {
  .page-about .about-hero {
    padding: 40px 34px 34px;
  }

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

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

@media (min-width: 900px) {
  .page-about .about-block {
    margin-top: 76px;
  }

  .page-about .about-hero {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr);
    align-items: end;
    gap: 40px;
    padding: 52px 44px 40px;
  }

  .page-about .about-tl-figure {
    margin: 28px 0 44px;
  }

  .page-about .tl {
    padding-left: 0;
  }

  .page-about .tl::before {
    left: 100px;
  }

  .page-about .tl__item {
    grid-template-columns: var(--about-tl-year) minmax(0, 1fr);
    gap: var(--about-gap);
    padding-bottom: 38px;
  }

  .page-about .tl__item::before {
    left: 95px;
    top: 8px;
  }

  .page-about .tl__mark {
    text-align: right;
    align-items: flex-end;
  }

  .page-about .tl__body {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr);
    gap: 26px;
    align-items: start;
  }

  .page-about .tl__item:nth-child(even) .tl__body {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.7fr);
  }

  .page-about .tl__item:nth-child(even) .tl__card {
    order: 2;
  }

  .page-about .tl__item:nth-child(even) .tl__aside {
    order: 1;
    text-align: right;
    border-left: 0;
    border-right: 1px solid var(--c-line);
    padding-left: 0;
    padding-right: 12px;
  }

  .page-about .about-cov-figure {
    margin-top: 0;
  }

  .page-about .about-team-figure {
    margin-top: 4px;
  }
}

@media (min-width: 1100px) {
  .page-about .certs {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl__item::before,
  .page-about .tl__year,
  .page-about .role__head,
  .page-about .certs__item {
    transition: none;
  }
}