.page-about {
  --about-shift: clamp(8px, 2.4vw, 30px);
  --about-line: rgba(47, 211, 192, 0.26);
  padding-top: calc(var(--header-h) + 16px);
  overflow-x: hidden;
}

/* 首屏 */
.page-about .about-hero {
  position: relative;
  padding-bottom: clamp(40px, 7vw, 88px);
}
.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: -20% -10% auto -10%;
  height: 130%;
  background:
    radial-gradient(110% 76% at 80% 0%, rgba(47, 211, 192, 0.16), transparent 62%),
    radial-gradient(80% 58% at 6% 18%, rgba(255, 106, 43, 0.1), transparent 70%);
  pointer-events: none;
}
.page-about .about-hero__inner {
  position: relative;
  display: grid;
  gap: clamp(32px, 5vw, 56px);
}
.page-about .about-hero__lead { max-width: 62ch; }
.page-about .about-hero h1 {
  margin: 12px 0 0;
  font-family: var(--font-display);
  font-size: clamp(30px, 5.6vw, 56px);
  line-height: 1.08;
  letter-spacing: -0.02em;
  font-weight: 900;
  color: var(--foam);
}
.page-about .about-hero__text {
  margin: 18px 0 0;
  max-width: 50ch;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist-400);
}
.page-about .about-hero__text a {
  color: var(--foam);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 106, 43, 0.6);
}
.page-about .about-hero__text a:hover { border-bottom-color: var(--lava-500); }
.page-about .about-hero__actions {
  margin-top: 28px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* 面包屑微调（仅本页作用域） */
.page-about .breadcrumb ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 20px;
  padding: 0;
  font-size: 13px;
  color: var(--mist-400);
}
.page-about .breadcrumb li { display: inline-flex; align-items: center; gap: 8px; }
.page-about .breadcrumb li + li::before {
  content: "";
  width: 10px;
  height: 1px;
  background: var(--mist-400);
  opacity: 0.55;
  transform: rotate(-12deg);
}
.page-about .breadcrumb a { color: var(--mist-400); text-decoration: none; }
.page-about .breadcrumb a:hover { color: var(--foam); }
.page-about .breadcrumb li[aria-current="page"] { color: var(--foam); }

/* 首屏数字 */
.page-about .about-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--glass-line);
  border: 1px solid var(--glass-line);
  border-radius: 2px;
  overflow: hidden;
}
.page-about .about-stats__item {
  background: var(--sea-700);
  padding: 18px 16px;
}
.page-about .about-stats dt {
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--mist-400);
}
.page-about .about-stats dd {
  margin: 10px 0 0;
  font-family: var(--font-num);
  font-size: 24px;
  line-height: 1.1;
  color: var(--foam);
}
.page-about .about-stats dd .num { color: var(--amber); }

/* 通用章节标题 */
.page-about .about-head { max-width: 64ch; }
.page-about .about-head h2 {
  margin: 10px 0 0;
  font-family: var(--font-display);
  font-size: clamp(26px, 3.6vw, 40px);
  line-height: 1.14;
  letter-spacing: -0.015em;
  font-weight: 800;
  color: var(--foam);
}
.page-about .about-head > p:not(.eyebrow) {
  margin: 14px 0 0;
  font-size: 16px;
  line-height: 1.8;
  color: var(--mist-400);
}

/* 图片 */
.page-about .about-figure { margin: 0; }
.page-about .about-figure img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border: 1px solid var(--glass-line);
  border-radius: 2px;
  background: var(--sea-700);
}
.page-about .about-figure figcaption {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist-400);
}
.page-about .about-figure--wide { margin-bottom: clamp(32px, 5vw, 56px); }
.page-about .about-figure--wide img { aspect-ratio: 16 / 9; }
.page-about .about-figure--flow { margin: 0 0 clamp(28px, 4vw, 44px); }
.page-about .about-figure--side img { aspect-ratio: 4 / 3; }

/* 时间线 */
.page-about .timeline {
  list-style: none;
  margin: clamp(28px, 4vw, 48px) 0 0;
  padding: 0;
  position: relative;
}
.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--tide-400) 0%, rgba(63, 191, 127, 0.42) 55%, rgba(63, 191, 127, 0) 100%);
}
.page-about .timeline__item {
  position: relative;
  padding-left: 34px;
  margin-bottom: 16px;
}
.page-about .timeline__item:last-child { margin-bottom: 0; }
.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 24px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 201, 74, 0.14);
}
.page-about .timeline__panel {
  background: var(--sea-700);
  border: 1px solid var(--glass-line);
  border-radius: 2px;
}
.page-about .timeline__panel[open] { border-color: rgba(47, 211, 192, 0.34); }
.page-about .timeline__summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 18px 20px;
  cursor: pointer;
  list-style: none;
}
.page-about .timeline__summary::-webkit-details-marker { display: none; }
.page-about .timeline__summary::marker { content: ""; }
.page-about .timeline__year {
  flex: none;
  font-family: var(--font-num);
  font-size: 17px;
  font-weight: 600;
  color: var(--amber);
  font-variant-numeric: tabular-nums;
}
.page-about .timeline__label {
  flex: 1 1 auto;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--foam);
}
.page-about .timeline__summary::after {
  content: "+";
  flex: none;
  font-family: var(--font-num);
  font-size: 18px;
  line-height: 1;
  color: var(--tide-400);
  transition: color 0.2s var(--ease);
}
.page-about .timeline__panel[open] .timeline__summary::after {
  content: "−";
  color: var(--lava-500);
}
.page-about .timeline__summary:hover .timeline__label { color: var(--foam); }
.page-about .timeline__summary:focus-visible {
  outline: 2px solid var(--lava-300);
  outline-offset: -3px;
}
.page-about .timeline__list {
  list-style: none;
  margin: 0;
  padding: 0 20px 20px;
  display: grid;
  gap: 10px;
}
.page-about .timeline__list li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist-400);
}
.page-about .timeline__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 12px;
  width: 10px;
  height: 1px;
  background: var(--tide-400);
  transform: rotate(-12deg);
}

/* 分工 */
.page-about .split-head { display: grid; gap: 28px; }
.page-about .roles {
  margin-top: clamp(28px, 4vw, 44px);
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}
.page-about .role {
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px;
  background: rgba(12, 43, 68, 0.72);
  border: 1px solid var(--glass-line);
  border-radius: 2px;
}
.page-about .role__meter {
  display: block;
  width: 100%;
  height: 6px;
  border-radius: 1px;
  background: linear-gradient(90deg, rgba(47, 211, 192, 0.9), rgba(63, 191, 127, 0.55));
}
.page-about .role__name {
  position: relative;
  z-index: 1;
  margin: 6px 0 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--foam);
}
.page-about .role__count {
  position: relative;
  z-index: 1;
  margin: 0;
  font-family: var(--font-num);
  font-size: 15px;
  color: var(--amber);
}
.page-about .role__desc {
  position: relative;
  z-index: 1;
  margin: 4px 0 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--mist-400);
}
.page-about .role__tasks {
  list-style: none;
  margin: 10px 0 0;
  padding: 0;
  display: grid;
  gap: 6px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--mist-400);
}
.page-about .role__tasks li {
  position: relative;
  padding-left: 14px;
}
.page-about .role__tasks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 7px;
  height: 1px;
  background: var(--tide-400);
  transform: rotate(-12deg);
}

/* 流程 */
.page-about .flow {
  list-style: none;
  margin: 0;
  padding: 0 clamp(20px, 8vw, 120px) 0 0;
}
.page-about .flow__step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  padding: 22px 0;
  border-top: 1px solid var(--hairline);
  transform: translateX(calc(var(--step, 0) * var(--about-shift)));
}
.page-about .flow__step:last-child { border-bottom: 1px solid var(--hairline); }
.page-about .flow__step:nth-child(1) { --step: 0; }
.page-about .flow__step:nth-child(2) { --step: 1; }
.page-about .flow__step:nth-child(3) { --step: 2; }
.page-about .flow__step:nth-child(4) { --step: 3; }
.page-about .flow__step:nth-child(5) { --step: 4; }
.page-about .flow__num {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  font-family: var(--font-num);
  font-size: 14px;
  font-weight: 600;
  color: var(--sea-900);
  background: linear-gradient(135deg, var(--tide-400) 0%, var(--lava-500) 100%);
}
.page-about .flow__body h3 {
  margin: 4px 0 0;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  color: var(--foam);
}
.page-about .flow__body p {
  margin: 8px 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist-400);
}
.page-about .flow__body a {
  color: var(--foam);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 106, 43, 0.6);
}
.page-about .flow__body a:hover { border-bottom-color: var(--lava-500); }

/* 合作生态 */
.page-about .partners {
  margin-top: clamp(24px, 3.5vw, 40px);
  display: grid;
  gap: 16px;
}
.page-about .partner {
  padding: 24px;
  border: 1px solid var(--glass-line);
  border-radius: 2px;
  background: linear-gradient(158deg, rgba(20, 64, 95, 0.78) 0%, rgba(12, 43, 68, 0.92) 100%);
}
.page-about .partner__num {
  margin: 0;
  font-family: var(--font-num);
  font-size: clamp(38px, 6vw, 54px);
  line-height: 1;
  font-weight: 600;
  color: var(--lava-500);
}
.page-about .partner h3 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  color: var(--foam);
}
.page-about .partner p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--mist-400);
}
.page-about .about-footnote {
  margin: clamp(20px, 3vw, 30px) 0 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--mist-400);
}
.page-about .about-footnote a {
  color: var(--foam);
  text-decoration: none;
  border-bottom: 1px solid rgba(255, 106, 43, 0.6);
}
.page-about .about-footnote a:hover { border-bottom-color: var(--lava-500); }

/* 认可 */
.page-about .honors {
  list-style: none;
  margin: clamp(24px, 3.5vw, 40px) 0 0;
  padding: 0;
}
.page-about .honors li {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid var(--hairline);
}
.page-about .honors li:first-child { border-top: 1px solid var(--hairline); }
.page-about .honors__year {
  font-family: var(--font-num);
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--tide-400);
}
.page-about .honors p {
  margin: 0;
  font-size: 15px;
  line-height: 1.78;
  color: var(--foam);
}

/* 两地 */
.page-about .cities {
  margin-top: clamp(24px, 3.5vw, 40px);
  display: grid;
  gap: 30px;
}
.page-about .city {
  padding-top: 20px;
  border-top: 1px solid var(--hairline);
}
.page-about .city h3 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  color: var(--foam);
}
.page-about .city p {
  margin: 10px 0 0;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist-400);
}
.page-about .city .city__tag {
  display: inline-block;
  margin-top: 14px;
  padding: 6px 12px;
  font-size: 13px;
  color: var(--tide-400);
  background: rgba(47, 211, 192, 0.1);
  border: 1px solid rgba(47, 211, 192, 0.3);
  border-radius: 2px;
}
.page-about .cities__note {
  margin: clamp(24px, 3.5vw, 36px) 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist-400);
}

/* 结尾 */
.page-about .about-cta__inner {
  display: grid;
  gap: 24px;
  padding: clamp(28px, 4.5vw, 48px);
  border: 1px solid var(--glass-line);
  border-radius: 2px;
  background:
    linear-gradient(120deg, rgba(20, 64, 95, 0.9) 0%, rgba(6, 26, 43, 0.9) 62%),
    radial-gradient(80% 120% at 100% 0%, rgba(255, 106, 43, 0.22), transparent 60%);
}
.page-about .about-cta h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.2;
  letter-spacing: -0.015em;
  font-weight: 800;
  color: var(--foam);
}
.page-about .about-cta p {
  margin: 12px 0 0;
  max-width: 52ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--mist-400);
}
.page-about .about-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* 平板及以上 */
@media (min-width: 780px) {
  .page-about .about-hero__inner {
    grid-template-columns: minmax(0, 7fr) minmax(0, 4fr);
    align-items: end;
    gap: clamp(40px, 6vw, 72px);
  }
  .page-about .about-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .about-stats dd { font-size: 28px; }

  .page-about .roles {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 16px;
    align-items: end;
  }
  .page-about .role {
    min-height: clamp(280px, 26vw, 340px);
    justify-content: flex-end;
    padding: 20px;
  }
  .page-about .role__meter {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    width: auto;
    border-radius: 0;
    height: var(--h, 50%);
    background: linear-gradient(180deg, rgba(47, 211, 192, 0.42) 0%, rgba(63, 191, 127, 0.1) 100%);
    border-top: 1px solid rgba(47, 211, 192, 0.45);
  }
  .page-about .role--edit { --h: 88%; }
  .page-about .role--data { --h: 66%; }
  .page-about .role--research { --h: 52%; }
  .page-about .role--support { --h: 34%; }
  .page-about .role__tasks { margin-top: 8px; }

  .page-about .split-head {
    grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
    align-items: end;
    gap: clamp(32px, 5vw, 64px);
  }
  .page-about .partners { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .page-about .honors li {
    grid-template-columns: 110px 1fr;
    gap: 24px;
    align-items: baseline;
    padding: 20px 0;
  }
  .page-about .cities {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: clamp(32px, 5vw, 64px);
  }
  .page-about .about-cta__inner {
    grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr);
    align-items: center;
    gap: 40px;
  }
  .page-about .about-cta__actions { justify-content: flex-end; }
}

@media (min-width: 780px) and (hover: hover) {
  .page-about .role__tasks {
    position: absolute;
    inset: 0;
    z-index: 2;
    margin: 0;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 10px;
    font-size: 13.5px;
    color: var(--foam);
    background: linear-gradient(165deg, rgba(6, 26, 43, 0.97) 0%, rgba(20, 64, 95, 0.94) 100%);
    opacity: 0;
    transition: opacity 0.3s var(--ease);
  }
  .page-about .role:hover .role__tasks,
  .page-about .role:focus-within .role__tasks { opacity: 1; }
}

@media (min-width: 1080px) {
  .page-about .about-hero { padding-bottom: clamp(72px, 8vw, 112px); }
  .page-about .timeline__item { padding-left: 48px; margin-bottom: 20px; }
  .page-about .timeline::before { left: 5px; }
  .page-about .timeline__summary { padding: 20px 28px; }
  .page-about .timeline__list { padding: 0 28px 22px; }
}