.page-about {
  color: var(--paper);
}

.page-about .about-intro {
  position: relative;
  padding: clamp(30px, 6vw, 58px) 0 clamp(34px, 5vw, 60px);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}

.page-about .about-intro::before {
  content: "";
  position: absolute;
  top: -38%;
  right: -14%;
  width: min(52vw, 560px);
  aspect-ratio: 1 / 1;
  background: radial-gradient(circle at 50% 50%, rgba(0, 229, 163, 0.16), rgba(0, 229, 163, 0) 66%);
  pointer-events: none;
}

.page-about .about-title {
  position: relative;
  margin: 16px 0 0;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(30px, 5.4vw, 56px);
  line-height: 1.16;
  letter-spacing: 0.01em;
  max-width: 15em;
}

.page-about .about-lede {
  position: relative;
  margin: 22px 0 0;
  max-width: 62ch;
  color: var(--muted);
}

.page-about .about-facts {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 14px clamp(18px, 4vw, 44px);
  margin: 30px 0 0;
  padding: 0;
  list-style: none;
}

.page-about .fact {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding-left: 12px;
  border-left: 1px solid var(--line);
}

.page-about .fact-k {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.page-about .fact-v {
  font-size: 18px;
  color: var(--paper);
}

/* --- 书脊 + 正文列 --- */
.page-about .spine-layout {
  display: grid;
  grid-template-columns: 1fr;
}

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

.page-about .spine-list {
  list-style: none;
  margin: 0;
  padding: 48px 0 0;
  position: relative;
}

.page-about .spine-list::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 56px;
  bottom: 24px;
  width: 1px;
  background: var(--line);
}

.page-about .spine-item {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 0 0 30px 24px;
}

.page-about .spine-item::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 5px;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--line);
}

.page-about .spine-item:first-child::before {
  background: var(--amber);
}

.page-about .spine-num {
  font-size: 11px;
  color: var(--muted);
}

.page-about .spine-word {
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 0.08em;
}

@media (min-width: 1000px) {
  .page-about .spine-layout {
    grid-template-columns: 104px minmax(0, 1fr);
    column-gap: clamp(24px, 4vw, 56px);
  }

  .page-about .spine {
    display: block;
    align-self: start;
    position: sticky;
    top: 92px;
  }
}

/* --- 章节通用 --- */
.page-about .about-sec {
  padding: clamp(52px, 8vw, 92px) 0;
  border-bottom: 1px solid var(--line);
}

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

.page-about .sec-head {
  margin-bottom: clamp(24px, 4vw, 38px);
}

.page-about .sec-title {
  margin: 12px 0 0;
  font-size: clamp(24px, 3.6vw, 38px);
  line-height: 1.24;
  max-width: 20em;
}

.page-about .sec-lede {
  margin: 18px 0 0;
  max-width: 62ch;
  color: var(--muted);
}

.page-about .sec-cols {
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.page-about .sec-main p {
  margin: 0 0 16px;
  max-width: 62ch;
  color: var(--paper);
}

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

@media (min-width: 900px) {
  .page-about .sec-cols {
    grid-template-columns: minmax(0, 1.55fr) 320px;
    gap: 40px;
    align-items: start;
  }
}

.page-about .mini-card {
  padding: 20px 22px;
}

.page-about .mini-meta {
  margin: 0 0 12px;
  color: var(--signal);
}

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

.page-about .mini-list li {
  position: relative;
  padding: 8px 0 8px 16px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--paper);
  border-bottom: 1px solid var(--line);
}

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

.page-about .mini-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--amber);
}

/* --- 三段工序 --- */
.page-about .flow {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr;
  gap: 26px;
}

.page-about .flow-step {
  position: relative;
  padding-left: 26px;
}

.page-about .flow-step::before {
  content: "";
  position: absolute;
  left: 0;
  top: 5px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 4px rgba(0, 229, 163, 0.14);
}

.page-about .flow-step:not(:last-child)::after {
  content: "";
  position: absolute;
  left: 4px;
  top: 22px;
  bottom: -24px;
  width: 1px;
  background: var(--line);
}

.page-about .flow-num {
  display: block;
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.page-about .flow-title {
  margin: 6px 0 8px;
  font-family: var(--font-sans);
  font-size: 18px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .flow-body {
  margin: 0;
  max-width: 40ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 820px) {
  .page-about .flow {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0;
  }

  .page-about .flow-step {
    padding: 30px 30px 0 0;
  }

  .page-about .flow-step::before {
    top: 0;
    left: 0;
  }

  .page-about .flow-step:not(:last-child)::after {
    left: 16px;
    right: 10px;
    top: 4px;
    bottom: auto;
    width: auto;
    height: 1px;
  }
}

.page-about .inline-link {
  margin: 26px 0 0;
  max-width: 62ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .inline-link a,
.page-about .partner-cta a {
  color: var(--signal);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 229, 163, 0.4);
  transition: border-color 0.16s var(--ease), color 0.16s var(--ease);
}

.page-about .inline-link a:hover,
.page-about .partner-cta a:hover {
  color: var(--paper);
  border-bottom-color: var(--paper);
}

/* --- 图片 --- */
.page-about .figure {
  margin: 34px 0 0;
}

.page-about .figure-media {
  border-radius: var(--r-md);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-800);
}

.page-about .figure-media img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: cover;
}

.page-about .figure-cap {
  margin-top: 10px;
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--muted);
}

.page-about .work-figure {
  max-width: 720px;
}

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

.page-about .timeline-figure {
  margin-top: 0;
  margin-bottom: 34px;
}

/* --- 反色插页：团队数字 --- */
.page-about .about-sec--plate {
  padding: clamp(44px, 7vw, 78px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .team-plate {
  background: var(--paper-inv);
  color: var(--ink-800);
  border-radius: var(--r-lg);
  padding: clamp(26px, 5vw, 54px);
}

.page-about .plate-meta {
  margin: 0;
  color: var(--signal-deep);
}

.page-about .plate-title {
  margin: 10px 0 0;
  font-size: clamp(24px, 3.4vw, 36px);
  line-height: 1.2;
  color: var(--ink-800);
}

.page-about .team-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  margin-top: 30px;
  padding-top: 26px;
  border-top: 1px solid rgba(12, 31, 26, 0.16);
}

.page-about .team-cell {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.page-about .team-num {
  font-family: var(--font-cond);
  font-weight: 700;
  font-size: clamp(46px, 9vw, 88px);
  line-height: 0.95;
  letter-spacing: -0.02em;
  color: var(--ink-800);
}

.page-about .team-cell:nth-child(3) .team-num {
  color: var(--signal-deep);
}

.page-about .team-label {
  font-size: 13px;
  line-height: 1.7;
  max-width: 24ch;
  color: rgba(12, 31, 26, 0.72);
}

.page-about .plate-foot {
  margin: 26px 0 0;
  padding-top: 20px;
  border-top: 1px solid rgba(12, 31, 26, 0.16);
  font-size: 14px;
  line-height: 1.8;
  max-width: 60ch;
  color: rgba(12, 31, 26, 0.72);
}

@media (min-width: 720px) {
  .page-about .team-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(20px, 4vw, 44px);
  }
}

/* --- 工程表格 --- */
.page-about .table-scroll {
  margin-top: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.page-about .pkg-table {
  width: 100%;
  min-width: 520px;
  border-collapse: collapse;
}

.page-about .pkg-table caption {
  text-align: left;
}

.page-about .pkg-table th,
.page-about .pkg-table td {
  padding: 13px 12px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
  font-size: 14px;
  line-height: 1.6;
}

.page-about .pkg-table thead th {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  border-bottom-color: var(--line);
}

.page-about .pkg-table tbody th {
  font-weight: 500;
  color: var(--paper);
  white-space: nowrap;
}

.page-about .pkg-table td {
  color: var(--muted);
}

.page-about .pkg-table td.mono {
  text-align: right;
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--signal);
  white-space: nowrap;
}

.page-about .pkg-table tbody tr:hover th,
.page-about .pkg-table tbody tr:hover td {
  background: rgba(0, 229, 163, 0.05);
}

.page-about .engine-notes {
  margin-top: 26px;
}

.page-about .engine-notes p {
  margin: 0 0 14px;
  max-width: 62ch;
  color: var(--paper);
}

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

/* --- 字段 --- */
.page-about .fields-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
}

.page-about .fields-text p {
  margin: 0 0 16px;
  max-width: 62ch;
  color: var(--paper);
}

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

@media (min-width: 900px) {
  .page-about .fields-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
    gap: clamp(28px, 5vw, 56px);
    align-items: start;
  }
}

/* --- 时间轴 --- */
.page-about .tl {
  list-style: none;
  margin: 0;
  padding: 0 0 0 26px;
  position: relative;
  border-left: 1px solid var(--line);
}

.page-about .tl-item {
  position: relative;
  padding: 0 0 26px 4px;
}

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

.page-about .tl-item::before {
  content: "";
  position: absolute;
  left: -32px;
  top: 7px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 0 0 4px rgba(242, 160, 61, 0.14);
  transition: transform 0.16s var(--ease);
}

.page-about .tl-item:hover::before,
.page-about .tl-item:focus-within::before {
  transform: scale(1.35);
}

.page-about .tl-node {
  display: flex;
  align-items: baseline;
  gap: 14px;
  outline: none;
  cursor: default;
}

.page-about .tl-node:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 4px;
  border-radius: 4px;
}

.page-about .tl-year {
  font-size: 12px;
  color: var(--muted);
  letter-spacing: 0.1em;
}

.page-about .tl-tag {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: clamp(17px, 2.4vw, 22px);
  color: var(--paper);
  letter-spacing: 0.01em;
}

.page-about .tl-note {
  margin: 8px 0 0;
  max-width: 56ch;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

@media (min-width: 900px) {
  .page-about .tl-note {
    max-height: 0;
    margin-top: 0;
    opacity: 0;
    overflow: hidden;
    transition: max-height 0.2s var(--ease), opacity 0.2s var(--ease), margin-top 0.2s var(--ease);
  }

  .page-about .tl-item:hover .tl-note,
  .page-about .tl-item:focus-within .tl-note {
    max-height: 7em;
    margin-top: 8px;
    opacity: 1;
  }
}

/* --- 共建 --- */
.page-about .partner-grid {
  margin-top: 4px;
}

.page-about .partner-card {
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.page-about .partner-card .chip {
  align-self: flex-start;
}

.page-about .partner-title {
  margin: 4px 0 0;
  font-family: var(--font-sans);
  font-size: 18px;
  font-weight: 600;
  color: var(--paper);
}

.page-about .partner-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.page-about .partner-cta {
  margin: 28px 0 0;
  max-width: 62ch;
  color: var(--paper);
}

/* --- 结尾 --- */
.page-about .about-cta {
  position: relative;
  padding: clamp(52px, 8vw, 92px) 0 clamp(40px, 6vw, 72px);
  border-bottom: 0;
}

.page-about .about-cta::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: min(180px, 40%);
  height: 3px;
  background: linear-gradient(90deg, var(--signal), var(--amber));
  border-radius: var(--r-pill);
}

.page-about .cta-title {
  margin: 0;
  font-size: clamp(26px, 4.2vw, 44px);
  line-height: 1.2;
  max-width: 18em;
}

.page-about .cta-text {
  margin: 18px 0 0;
  max-width: 58ch;
  color: var(--muted);
}

.page-about .cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

@media (prefers-reduced-motion: reduce) {
  .page-about .tl-item::before,
  .page-about .tl-node,
  .page-about .inline-link a,
  .page-about .partner-cta a {
    transition: none;
  }

  .page-about .tl-note {
    max-height: none;
    opacity: 1;
    margin-top: 8px;
  }

  .page-about .tl-item:hover::before,
  .page-about .tl-item:focus-within::before {
    transform: none;
  }
}