.page-about {
  --about-rail: 112px;
  --about-indent: 2.35rem;
  display: block;
  background: var(--ink);
  color: var(--paper);
}

/* ---------- 面包屑 ---------- */
.page-about .about-crumbs {
  padding-top: clamp(0.9rem, 2.5vw, 1.5rem);
  padding-bottom: clamp(0.5rem, 1.5vw, 0.9rem);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(1.5rem, 5vw, 3rem) 0 clamp(2.5rem, 6vw, 4.5rem);
  background:
    radial-gradient(120% 92% at 84% 2%, rgba(198, 255, 61, 0.1), transparent 56%),
    radial-gradient(100% 80% at 2% 104%, rgba(255, 107, 44, 0.13), transparent 62%),
    linear-gradient(180deg, var(--ink) 0%, var(--green-deep) 100%);
  border-bottom: 1px solid var(--grid);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(90deg, rgba(42, 58, 49, 0.6) 0 1px, transparent 1px 76px),
    repeating-linear-gradient(0deg, rgba(42, 58, 49, 0.6) 0 1px, transparent 1px 76px);
  opacity: 0.5;
  pointer-events: none;
}

.page-about .about-hero__inner {
  position: relative;
  z-index: 1;
  max-width: 60rem;
}

.page-about .about-hero h1 {
  margin: 0.6rem 0 1rem;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(1.9rem, 6.4vw, 4.1rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  color: var(--paper);
  text-wrap: balance;
}

.page-about .about-hero .lede {
  max-width: 46rem;
  margin: 0;
}

.page-about .about-hero__stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin-top: clamp(1.6rem, 4vw, 2.4rem);
  background: var(--grid);
  border: 1px solid var(--grid);
  border-radius: var(--r-md);
  overflow: hidden;
}

.page-about .about-hero__stats .stat {
  background: rgba(10, 15, 12, 0.94);
  padding: 0.95rem 1.05rem 1rem;
}

.page-about .about-hero__stats .stat__value {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(1.45rem, 4.4vw, 2.05rem);
  font-weight: 700;
  line-height: 1.1;
  color: var(--lime);
  letter-spacing: -0.01em;
}

.page-about .about-hero__stats .stat__label {
  display: block;
  margin-top: 0.35rem;
  font-size: 0.82rem;
  line-height: 1.5;
  color: var(--mist);
}

.page-about .about-hero__media {
  position: relative;
  z-index: 1;
  margin-top: clamp(1.8rem, 5vw, 3rem);
}

/* ---------- 正文骨架：左刻度尺 + 内容列 ---------- */
.page-about .about-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.5rem, 4vw, 2.75rem);
  padding: clamp(2.2rem, 6vw, 4.5rem) 0 clamp(2.5rem, 7vw, 5rem);
}

.page-about .about-rail {
  display: none;
}

.page-about .about-flow {
  min-width: 0;
}

/* ---------- 章节 ---------- */
.page-about .about-chapter {
  position: relative;
  padding: clamp(1.7rem, 4.5vw, 2.75rem) 0;
  border-top: 1px solid var(--grid);
}

.page-about .about-chapter:first-of-type {
  border-top: 0;
  padding-top: 0;
}

.page-about .about-chapter__note {
  display: none;
}

.page-about .about-chapter .section-title {
  margin: 0.5rem 0 1.1rem;
}

.page-about .about-chapter .prose p {
  max-width: 46rem;
}

.page-about .about-inline-link {
  margin: 0.9rem 0 0;
  font-size: 0.92rem;
}

.page-about .about-inline-link a {
  color: var(--lime);
  text-decoration: none;
  border-bottom: 1px solid rgba(198, 255, 61, 0.35);
  padding-bottom: 1px;
}

.page-about .about-inline-link a:hover {
  color: var(--flare);
  border-bottom-color: var(--flare);
}

/* ---------- 版本时间线 ---------- */
.page-about .about-timeline {
  position: relative;
  margin: 1.5rem 0 0;
  padding-left: var(--about-indent);
}

.page-about .about-timeline__line {
  position: absolute;
  left: 0;
  top: 0;
  width: 40px;
  height: 100%;
  pointer-events: none;
}

.page-about .about-timeline__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .about-timeline__item {
  position: relative;
  padding-bottom: clamp(1.4rem, 4vw, 2.1rem);
}

.page-about .about-timeline__item:last-child {
  padding-bottom: 0.25rem;
}

.page-about .about-timeline__item::before {
  content: "";
  position: absolute;
  left: calc(var(--about-indent) * -1 - 7px);
  top: 0.45rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--node, var(--turf));
  box-shadow: 0 0 0 5px rgba(10, 15, 12, 0.92);
}

.page-about .about-timeline__item::after {
  content: "";
  position: absolute;
  left: calc(var(--about-indent) * -1 - 7px);
  top: 0.45rem;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 1px solid var(--node, var(--turf));
  animation: about-node-pulse 1.2s ease-in-out infinite;
  pointer-events: none;
}

@keyframes about-node-pulse {
  0%, 100% { transform: scale(1); opacity: 0.75; }
  50% { transform: scale(1.9); opacity: 0; }
}

.page-about .about-node--1 { --node: var(--turf); }
.page-about .about-node--2 { --node: #3A8450; }
.page-about .about-node--3 { --node: #7AAE3F; }
.page-about .about-node--4 { --node: var(--lime); }

.page-about .about-timeline__ver {
  margin: 0 0 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--node, var(--turf));
}

.page-about .about-timeline__title {
  margin: 0 0 0.5rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.08rem, 2.8vw, 1.32rem);
  line-height: 1.35;
  color: var(--paper);
}

.page-about .about-timeline__desc {
  margin: 0;
  max-width: 42rem;
  font-size: clamp(0.94rem, 1.6vw, 1rem);
  line-height: 1.78;
  color: var(--mist);
}

.page-about .about-timeline__media {
  margin-top: clamp(1.5rem, 4vw, 2.25rem);
}

/* ---------- 合作生态矩阵 ---------- */
.page-about .about-matrix {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.9rem;
  margin-top: 1.5rem;
}

.page-about .about-matrix__cell {
  position: relative;
  padding: 1.1rem 1.15rem 1.2rem;
  background: linear-gradient(158deg, var(--green-mid), var(--green-deep));
  border: 1px solid var(--grid);
  border-radius: 22px 22px 22px 8px;
  transition: transform 0.28s ease, border-color 0.28s ease;
}

.page-about .about-matrix__cell:nth-child(even) {
  border-radius: 8px 22px 22px 22px;
}

.page-about .about-matrix__cell:hover,
.page-about .about-matrix__cell:focus-within {
  transform: translateY(-4px);
  border-color: var(--turf);
}

.page-about .about-matrix__num {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 5vw, 2.3rem);
  font-weight: 700;
  line-height: 1;
  color: var(--lime);
}

.page-about .about-matrix__head {
  margin: 0.55rem 0 0.6rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1rem;
  line-height: 1.4;
  color: var(--paper);
}

.page-about .about-matrix__desc {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.72;
  color: var(--mist);
}

.page-about .about-matrix__extra {
  margin: 0.8rem 0 0;
  padding-top: 0.7rem;
  border-top: 1px dashed var(--grid);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--flare);
  opacity: 0.85;
  transition: opacity 0.28s ease, color 0.28s ease;
}

.page-about .about-matrix__cell:hover .about-matrix__extra {
  opacity: 1;
  color: var(--stand);
}

/* ---------- 数据管理分栏 ---------- */
.page-about .about-split {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(1.3rem, 3.5vw, 2rem);
  align-items: start;
  margin-top: 0.5rem;
}

.page-about .about-split__text p {
  max-width: 40rem;
}

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

/* ---------- 资质清单 ---------- */
.page-about .about-creds {
  list-style: none;
  margin: 1.6rem 0 0;
  padding: 0;
  border: 1px solid var(--grid);
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--green-deep);
}

.page-about .about-creds__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.78rem 1rem;
  border-bottom: 1px solid var(--grid);
}

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

.page-about .about-creds__row:nth-child(odd) {
  background: rgba(22, 69, 47, 0.42);
}

.page-about .about-creds__k {
  font-size: 0.88rem;
  color: var(--mist);
}

.page-about .about-creds__v {
  font-family: var(--font-mono);
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--lime);
  white-space: nowrap;
}

/* ---------- 发展目标折叠 ---------- */
.page-about .about-goals {
  margin-top: 1.4rem;
}

.page-about .about-goal {
  margin: 0 0 0.7rem;
  padding: 0 1.05rem;
  background: var(--green-deep);
  border: 1px solid var(--grid);
  border-radius: var(--r-md);
  transition: border-color 0.28s ease;
}

.page-about .about-goal:hover {
  border-color: var(--turf);
}

.page-about .about-goal[open] {
  border-color: var(--turf);
}

.page-about .about-goal summary {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  padding: 0.95rem 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1rem, 2.4vw, 1.14rem);
  line-height: 1.45;
  color: var(--paper);
}

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

.page-about .about-goal summary::after {
  content: "展开";
  margin-left: auto;
  flex: none;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 400;
  letter-spacing: 0.14em;
  color: var(--lime);
}

.page-about .about-goal[open] summary::after {
  content: "收起";
  color: var(--flare);
}

.page-about .about-goal__body {
  padding: 0 0 1.05rem;
}

.page-about .about-goal__body p {
  margin: 0;
  max-width: 44rem;
  font-size: clamp(0.92rem, 1.6vw, 1rem);
  line-height: 1.78;
  color: var(--mist);
}

.page-about .about-closing {
  margin: clamp(1.5rem, 4vw, 2.2rem) 0 0;
  padding-left: 1rem;
  border-left: 3px solid var(--lime);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1rem, 2.6vw, 1.22rem);
  line-height: 1.65;
  color: var(--paper);
  max-width: 40rem;
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-about .about-hero__stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

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

@media (min-width: 900px) {
  .page-about .about-body {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
  }

  .page-about .about-rail {
    display: block;
    position: sticky;
    top: 7.5rem;
    align-self: start;
    padding-left: 1rem;
    border-left: 1px solid var(--grid);
  }

  .page-about .about-rail__title {
    margin: 0 0 0.9rem;
    font-family: var(--font-mono);
    font-size: 0.68rem;
    letter-spacing: 0.22em;
    color: var(--mist);
  }

  .page-about .about-rail__list {
    list-style: none;
    margin: 0;
    padding: 0;
  }

  .page-about .about-rail__item {
    position: relative;
    display: flex;
    align-items: baseline;
    gap: 0.5rem;
    padding: 0.42rem 0 0.42rem 0.9rem;
    font-size: 0.82rem;
    color: var(--mist);
  }

  .page-about .about-rail__item::before {
    content: "";
    position: absolute;
    left: -1px;
    top: 50%;
    width: 9px;
    height: 1px;
    background: var(--grid);
  }

  .page-about .about-rail__num {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--turf);
  }

  .page-about .about-split {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  }

  .page-about .about-timeline__media {
    max-width: 34rem;
    margin-left: auto;
    margin-right: 0;
  }

  .page-about .about-chapter .prose p {
    font-size: 1.02rem;
    line-height: 1.82;
  }
}

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

  .page-about .about-matrix__cell:nth-child(2) {
    margin-top: 1.4rem;
  }

  .page-about .about-matrix__cell:nth-child(4) {
    margin-top: 0.7rem;
  }
}

@media (min-width: 1280px) {
  .page-about .about-chapter__note {
    display: block;
    position: absolute;
    right: -3.1rem;
    top: 2.9rem;
    transform: rotate(90deg);
    transform-origin: left top;
    white-space: nowrap;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.24em;
    color: var(--grid);
    pointer-events: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .about-timeline__item::after {
    animation: none;
  }

  .page-about .about-matrix__cell,
  .page-about .about-matrix__extra,
  .page-about .about-goal {
    transition: none;
  }
}