.page-about {
  --about-gap: clamp(44px, 6vw, 84px);
  --about-shadow: 0 18px 44px rgba(11, 42, 34, .08);
  --about-shadow-hi: 0 26px 60px rgba(11, 42, 34, .14);
  background: var(--mist);
  color: var(--ink);
  padding-bottom: 0;
  overflow-x: clip;
}

.page-about .crumb {
  padding: 22px 0 20px;
  font-size: .8125rem;
  letter-spacing: .06em;
  color: var(--txt-dim);
}

.page-about .crumb a {
  color: var(--grass);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--t) var(--ease);
}

.page-about .crumb a:hover,
.page-about .crumb a:focus-visible {
  border-bottom-color: var(--grass);
}

.page-about .crumb__sep {
  margin: 0 .5em;
  color: var(--line);
}

/* ---------- Hero ---------- */

.page-about .about-hero {
  position: relative;
  margin: 0 0 var(--about-gap);
  padding: clamp(28px, 5vw, 56px) clamp(20px, 4vw, 52px) clamp(26px, 4vw, 48px);
  border-radius: var(--radius-xl);
  background: radial-gradient(120% 140% at 8% 0%, #16452f 0%, var(--night-2) 42%, var(--night) 100%);
  color: var(--mist);
  overflow: hidden;
  isolation: isolate;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--grass) 0%, var(--grass-hi) 34%, var(--amber) 72%, transparent 100%);
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  right: -12%;
  bottom: -46%;
  width: 70%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(63, 167, 106, .28) 0%, rgba(63, 167, 106, 0) 68%);
  pointer-events: none;
  z-index: -1;
}

.page-about .about-hero .eyebrow {
  position: relative;
  z-index: 1;
  color: var(--amber-hi);
}

.page-about .about-hero h1 {
  position: relative;
  z-index: 1;
  margin: 14px 0 22px;
  max-width: 18ch;
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 6.4vw, 4.25rem);
  font-weight: 300;
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-about .about-hero__lead {
  position: relative;
  z-index: 1;
  max-width: 62ch;
  margin: 0 0 34px;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--txt-soft);
}

.page-about .hero-facts {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  padding: 0;
  list-style: none;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--line-soft);
}

.page-about .hero-facts__item {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px 16px 20px;
  background: rgba(18, 56, 44, .72);
  backdrop-filter: blur(2px);
}

.page-about .hero-facts__num {
  font-family: var(--font-mono);
  font-size: clamp(1.85rem, 5.6vw, 2.6rem);
  font-weight: 400;
  line-height: 1;
  letter-spacing: 0;
  color: var(--amber);
}

.page-about .hero-facts__label {
  font-size: .75rem;
  line-height: 1.5;
  letter-spacing: .08em;
  color: var(--txt-soft);
}

/* ---------- 通用章节骨架 ---------- */

.page-about .about-sec {
  margin: 0 0 var(--about-gap);
}

.page-about .chapter {
  position: relative;
  padding-left: 0;
}

.page-about .chapter__no {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(3.5rem, 12vw, 7.5rem);
  font-weight: 300;
  line-height: .84;
  letter-spacing: -0.04em;
  color: transparent;
  -webkit-text-stroke: 1px var(--grass);
  margin-bottom: 6px;
}

.page-about .chapter__title {
  margin: 0 0 18px;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4.4vw, 2.6rem);
  font-weight: 400;
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--night);
}

.page-about .chapter__body p {
  max-width: 64ch;
  margin: 0 0 16px;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--ink);
}

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

/* ---------- 时间轴 ---------- */

.page-about .timeline {
  position: relative;
  margin: 34px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .timeline::before {
  content: "";
  position: absolute;
  left: 11px;
  top: 10px;
  bottom: 14px;
  width: 2px;
  border-radius: var(--pill);
  background: linear-gradient(180deg, var(--grass) 0%, var(--grass) 62%, rgba(63, 167, 106, .16) 100%);
}

.page-about .timeline__item {
  position: relative;
  padding: 0 0 30px 46px;
}

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

.page-about .timeline__item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--mist);
  border: 2px solid var(--grass);
  box-shadow: 0 0 0 5px rgba(63, 167, 106, .13);
  transition: border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}

.page-about .timeline__item--now::before {
  border-color: var(--amber);
  box-shadow: 0 0 0 6px rgba(242, 160, 61, .18);
}

.page-about .timeline__item:hover::before {
  border-color: var(--grass-hi);
  box-shadow: 0 0 0 7px rgba(123, 215, 154, .22);
}

.page-about .timeline__item--now:hover::before {
  border-color: var(--amber);
  box-shadow: 0 0 0 8px rgba(242, 160, 61, .24);
}

.page-about .timeline__mark {
  display: inline-block;
  margin-bottom: 8px;
  padding: 4px 12px;
  border-radius: var(--pill);
  background: rgba(63, 167, 106, .12);
  font-family: var(--font-mono);
  font-size: .8125rem;
  letter-spacing: .04em;
  color: var(--night);
}

.page-about .timeline__item--now .timeline__mark {
  background: var(--amber-hi);
  color: var(--night);
}

.page-about .timeline__title {
  margin: 0 0 8px;
  font-size: 1.0625rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--night);
}

.page-about .timeline__box p {
  max-width: 60ch;
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--txt-dim);
}

/* ---------- 团队与工作线 ---------- */

.page-about .team-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  margin-top: 30px;
}

.page-about .worklines {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-about .workline {
  --accent: var(--grass);
  position: relative;
  padding: 22px 20px 20px;
  border-radius: var(--radius-lg);
  background: #fff;
  border: 1px solid var(--edge);
  box-shadow: var(--about-shadow);
  overflow: hidden;
  transition: transform var(--t) var(--ease), box-shadow var(--t) var(--ease), border-color var(--t) var(--ease);
}

.page-about .workline:nth-child(2) { --accent: var(--grass-hi); }
.page-about .workline:nth-child(3) { --accent: var(--amber); }
.page-about .workline:nth-child(4) { --accent: var(--amber-hi); }

.page-about .workline__bar {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--accent);
  transition: width var(--t) var(--ease);
}

.page-about .workline:hover,
.page-about .workline:focus-within {
  transform: translateY(-3px);
  border-color: rgba(63, 167, 106, .3);
  box-shadow: var(--about-shadow-hi);
}

.page-about .workline:hover .workline__bar,
.page-about .workline:focus-within .workline__bar {
  width: 6px;
}

.page-about .workline__title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--night);
}

.page-about .workline__desc {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.78;
  color: var(--ink);
}

.page-about .workline__more {
  max-height: 0;
  margin: 0;
  overflow: hidden;
  opacity: 0;
  font-size: .875rem;
  line-height: 1.78;
  color: var(--txt-dim);
  transition: max-height 300ms var(--ease), opacity 220ms var(--ease), margin 300ms var(--ease);
}

.page-about .workline:hover .workline__more,
.page-about .workline:focus-within .workline__more {
  max-height: 12rem;
  margin-top: 12px;
  opacity: 1;
}

@media (hover: none) {
  .page-about .workline__more {
    max-height: none;
    margin-top: 12px;
    opacity: 1;
  }
}

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

.page-about .about-figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  background: var(--panel);
  border: 1px solid var(--edge);
  object-fit: cover;
}

.page-about .about-figure figcaption {
  margin-top: 12px;
  font-size: .8125rem;
  line-height: 1.7;
  letter-spacing: .06em;
  color: var(--txt-dim);
}

/* ---------- 覆盖范围 ---------- */

.page-about .coverage-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
  margin-top: 30px;
}

.page-about .coverage-body__title {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--night);
}

.page-about .project-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 22px;
  padding: 0;
  list-style: none;
}

.page-about .project-list__item {
  padding: 8px 16px;
  border-radius: var(--pill);
  background: var(--night-2);
  color: var(--mist);
  font-size: .875rem;
  letter-spacing: .04em;
}

.page-about .project-list__item--rest {
  background: transparent;
  border: 1px solid var(--grass);
  color: var(--grass);
}

.page-about .coverage-body p {
  max-width: 60ch;
  margin: 0 0 16px;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--ink);
}

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

/* ---------- 校验流程 ---------- */

.page-about .flow {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
  counter-reset: flowstep;
}

.page-about .flow__step {
  --step: var(--grass);
  position: relative;
  padding: 24px 20px 22px;
  border-radius: var(--radius-lg);
  background: #fff;
  border: 1px solid var(--edge);
  border-top: 3px solid var(--step);
}

.page-about .flow__step:nth-child(2) { --step: var(--grass-hi); }
.page-about .flow__step:nth-child(3) { --step: var(--amber); }
.page-about .flow__step:nth-child(4) { --step: var(--amber-hi); }

.page-about .flow__badge {
  display: inline-block;
  margin-bottom: 14px;
  padding: 5px 14px;
  border-radius: var(--pill);
  background: var(--step);
  color: var(--night);
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .12em;
}

.page-about .flow__title {
  margin: 0 0 10px;
  font-size: 1.0625rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--night);
}

.page-about .flow__step p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--txt-dim);
}

/* ---------- 版本演进 ---------- */

.page-about .about-figure--version {
  margin-top: 30px;
}

.page-about .versions {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--panel);
}

.page-about .versions__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 6px;
  padding: 20px 20px 22px;
  border-bottom: 1px solid var(--zebra);
}

.page-about .versions__row:last-child {
  border-bottom: 0;
}

.page-about .versions__row--now {
  background: rgba(242, 160, 61, .13);
}

.page-about .versions__key {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  letter-spacing: 0;
  color: var(--night);
}

.page-about .versions__row--now .versions__key {
  color: #8a5410;
}

.page-about .versions__title {
  margin: 0 0 6px;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--night);
}

.page-about .versions__body p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.78;
  color: var(--txt-dim);
}

/* ---------- 合作生态 ---------- */

.page-about .partner-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-top: 30px;
}

.page-about .partner {
  padding: 24px 20px 22px;
  border-radius: var(--radius-lg);
  background: var(--night);
  color: var(--mist);
  border: 1px solid rgba(63, 167, 106, .22);
}

.page-about .partner__num {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 2rem;
  line-height: 1;
  letter-spacing: 0;
  color: var(--grass-hi);
}

.page-about .partner__title {
  margin: 0 0 10px;
  font-size: 1.0625rem;
  font-weight: 600;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .partner p {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.8;
  color: var(--txt-soft);
}

.page-about .honors {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-top: 12px;
}

.page-about .honor {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 20px;
  border-radius: var(--radius-lg);
  background: #fff;
  border: 1px solid var(--edge);
}

.page-about .honor__year {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 1.125rem;
  letter-spacing: 0;
  color: var(--amber);
}

.page-about .honor__text {
  margin: 0;
  font-size: .9375rem;
  line-height: 1.75;
  color: var(--ink);
}

/* ---------- 结尾深色带 ---------- */

.page-about .about-outro {
  position: relative;
  margin-top: var(--about-gap);
  padding: clamp(38px, 6vw, 76px) clamp(20px, 4vw, 52px);
  background: linear-gradient(168deg, var(--night) 0%, var(--night-2) 54%, #14503a 100%);
  color: var(--mist);
}

.page-about .about-outro::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent 0%, var(--grass) 30%, var(--amber) 72%, transparent 100%);
}

.page-about .about-outro__inner {
  max-width: var(--wrap);
  margin: 0 auto;
}

.page-about .about-outro .eyebrow {
  color: var(--amber-hi);
}

.page-about .about-outro__title {
  margin: 14px 0 22px;
  max-width: 20ch;
  font-family: var(--font-display);
  font-size: clamp(1.75rem, 5vw, 3rem);
  font-weight: 300;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-about .about-outro__text {
  max-width: 64ch;
  margin: 0 0 34px;
  font-size: 1.0625rem;
  line-height: 1.85;
  color: var(--txt-soft);
}

.page-about .about-outro__facts {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1px;
  margin: 0 0 34px;
  padding: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--line-soft);
}

.page-about .about-outro__fact {
  padding: 16px 18px;
  background: rgba(11, 42, 34, .55);
}

.page-about .about-outro__fact dt {
  margin-bottom: 6px;
  font-size: .75rem;
  letter-spacing: .1em;
  color: var(--amber-hi);
}

.page-about .about-outro__fact dd {
  margin: 0;
  font-family: var(--font-mono);
  font-size: .9375rem;
  line-height: 1.7;
  color: var(--mist);
  word-break: break-word;
}

.page-about .about-outro__links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.page-about .about-outro__links .btn {
  text-decoration: none;
}

/* ---------- 响应式 ---------- */

@media (min-width: 600px) {
  .page-about .hero-facts {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

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

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

  .page-about .versions__row {
    grid-template-columns: 150px minmax(0, 1fr);
    align-items: start;
    gap: 24px;
  }

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

@media (min-width: 900px) {
  .page-about .coverage-split {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
    align-items: center;
    gap: 40px;
  }

  .page-about .coverage-split .about-figure {
    order: -1;
  }

  .page-about .partner-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1024px) {
  .page-about .team-split {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, .85fr);
    align-items: start;
    gap: 32px;
  }

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

@media (min-width: 1180px) {
  .page-about .flow {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-about .chapter {
    padding-left: 118px;
  }

  .page-about .chapter__no {
    position: absolute;
    left: 0;
    top: -8px;
    margin-bottom: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .workline,
  .page-about .workline__more,
  .page-about .workline__bar,
  .page-about .timeline__item::before {
    transition: none;
  }

  .page-about .workline:hover,
  .page-about .workline:focus-within {
    transform: none;
  }
}