.page-about {
  --about-rail: 44px;
  --about-line: 2px;
  --about-paper-text: #23282a;
  color: var(--white);
}

/* ---------- 面包屑 ---------- */
.page-about .crumb {
  padding-top: clamp(14px, 3vw, 22px);
}

/* ---------- 首屏 ---------- */
.page-about .about-hero {
  position: relative;
  padding: clamp(20px, 4vw, 40px) 0 clamp(34px, 6vw, 68px);
  border-bottom: var(--about-line) solid var(--grid);
  overflow: hidden;
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 72px 72px;
  opacity: 0.32;
  pointer-events: none;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  top: -30%;
  left: 50%;
  width: min(900px, 120%);
  height: 620px;
  transform: translateX(-50%);
  background: radial-gradient(ellipse at center, rgba(53, 242, 208, 0.16), transparent 68%);
  pointer-events: none;
}

.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(22px, 4vw, 40px);
}

.page-about .about-kicker {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-about .about-hero h1 {
  margin: 0 0 16px;
  font-size: clamp(1.75rem, 5.2vw, 3.1rem);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--white);
  max-width: 22ch;
}

.page-about .about-lede {
  margin: 0 0 22px;
  max-width: 48ch;
  font-size: var(--fs-17);
  line-height: 1.8;
  color: var(--mist);
}

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

.page-about .about-hero-media {
  border: var(--about-line) solid var(--grid);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
  margin: 0;
  background: var(--carbon);
}

.page-about .about-hero-media img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

/* ---------- 通用章节骨架：左栏编号 + 右栏内容 ---------- */
.page-about .about-section {
  position: relative;
}

.page-about .about-row {
  display: grid;
  grid-template-columns: var(--about-rail) minmax(0, 1fr);
  gap: clamp(12px, 3vw, 30px);
  align-items: start;
}

.page-about .about-rail {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  align-self: stretch;
  min-height: 90px;
}

.page-about .about-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 38px;
  height: 34px;
  padding: 0 6px;
  border: var(--about-line) solid var(--gold);
  background: var(--ink-2);
  color: var(--gold);
  font-size: var(--fs-14);
  font-weight: 700;
  letter-spacing: 0.06em;
}

.page-about .about-rail-line {
  flex: 1;
  width: var(--about-line);
  background: linear-gradient(180deg, var(--grid) 0%, rgba(30, 58, 51, 0) 100%);
}

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

.page-about .section-head {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: clamp(16px, 3vw, 26px);
}

.page-about .section-title {
  margin: 0;
  font-size: clamp(1.3rem, 3.2vw, 1.95rem);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: -0.015em;
  color: var(--white);
}

.page-about .section-note {
  margin: 0;
  max-width: 58ch;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--mist);
  text-align: left;
}

.page-about .about-text p {
  margin: 0 0 14px;
  font-size: var(--fs-17);
  line-height: 1.8;
  color: var(--white);
}

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

.page-about .about-text--tight {
  margin-top: clamp(16px, 3vw, 24px);
  padding-left: clamp(12px, 2.5vw, 18px);
  border-left: 4px solid var(--gold);
}

/* ---------- 版本时间线 ---------- */
.page-about .version-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-about .version-item {
  position: relative;
  margin-left: 7px;
  padding: 0 0 clamp(20px, 3.5vw, 28px) clamp(16px, 3vw, 26px);
  border-left: var(--about-line) solid var(--grid);
}

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

.page-about .version-item::before {
  content: "";
  position: absolute;
  left: -8px;
  top: 5px;
  width: 14px;
  height: 14px;
  background: var(--gold);
  border: var(--about-line) solid var(--ink);
  box-shadow: 0 0 0 2px var(--grid);
}

.page-about .version-item.is-current::before {
  background: var(--cyan);
  box-shadow: 0 0 0 2px var(--cyan), 0 0 14px rgba(53, 242, 208, 0.55);
}

.page-about .version-tag {
  display: inline-block;
  font-size: var(--fs-12);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
}

.page-about .version-item.is-current .version-tag {
  color: var(--cyan);
}

.page-about .version-title {
  margin: 6px 0 8px;
  font-size: clamp(1.05rem, 2.4vw, 1.3rem);
  font-weight: 800;
  line-height: 1.35;
  color: var(--white);
}

.page-about .version-desc {
  margin: 0;
  max-width: 62ch;
  font-size: var(--fs-17);
  line-height: 1.78;
  color: var(--mist);
}

.page-about .about-inline-media {
  margin: clamp(20px, 4vw, 32px) 0 0;
  border: var(--about-line) solid var(--grid);
  box-shadow: var(--shadow-hard);
  background: var(--carbon);
  overflow: hidden;
}

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

.page-about .about-inline-media figcaption {
  padding: 12px clamp(12px, 2.5vw, 18px);
  border-top: var(--about-line) solid var(--grid);
  font-size: var(--fs-14);
  line-height: 1.65;
  color: var(--mist);
}

/* ---------- 值班带 ---------- */
.page-about .about-section--shift {
  background: linear-gradient(180deg, rgba(15, 46, 39, 0) 0%, rgba(15, 46, 39, 0.85) 45%, rgba(15, 46, 39, 0) 100%);
}

.page-about .shift-band {
  margin-top: clamp(18px, 3vw, 28px);
  padding: clamp(16px, 3vw, 26px);
  border: var(--about-line) solid var(--grid);
  background: var(--carbon);
  box-shadow: var(--shadow-hard);
}

.page-about .shift-band-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.page-about .shift-band-label {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: 0.08em;
  color: var(--mist);
}

.page-about .shift-track {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 4px;
  margin-top: 16px;
}

.page-about .shift-cell {
  padding: 12px 2px;
  border: 1px solid var(--grid);
  background: var(--ink-2);
  color: var(--mist);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.02em;
  text-align: center;
  transition: background 0.2s var(--ease), color 0.2s var(--ease), transform 0.2s var(--ease);
}

.page-about .shift-cell.is-peak {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}

.page-about .shift-cell.is-tail {
  background: var(--ink);
  color: var(--rose);
  border-color: rgba(255, 61, 110, 0.45);
}

@media (hover: hover) {
  .page-about .shift-cell:hover {
    transform: translateY(-2px);
    background: var(--gold);
    border-color: var(--gold);
    color: var(--ink);
  }
}

.page-about .shift-band-note {
  margin: 14px 0 0;
  font-size: var(--fs-14);
  line-height: 1.7;
  color: var(--mist);
}

/* ---------- 规模数据 ---------- */
.page-about .stat-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(10px, 2vw, 16px);
}

.page-about .stat-cell {
  padding: clamp(14px, 2.4vw, 20px);
  border: var(--about-line) solid var(--grid);
  background: var(--carbon);
  box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.5);
}

.page-about .stat-line {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 4px;
  margin: 0;
  font-family: var(--font-mono);
  color: var(--cyan);
}

.page-about .stat-num {
  font-size: clamp(1.7rem, 4.4vw, 2.35rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
}

.page-about .stat-unit {
  font-size: var(--fs-14);
  letter-spacing: 0.04em;
}

.page-about .stat-cell.is-gold .stat-line {
  color: var(--gold);
}

.page-about .stat-label {
  margin: 10px 0 0;
  font-size: var(--fs-14);
  line-height: 1.6;
  color: var(--mist);
}

/* ---------- 合作生态 ---------- */
.page-about .partner-grid {
  display: grid;
  gap: clamp(12px, 2.4vw, 18px);
}

.page-about .partner-card {
  padding: clamp(15px, 2.6vw, 22px);
  border: var(--about-line) solid var(--grid);
  border-left: 6px solid var(--gold);
  background: var(--ink-2);
}

.page-about .partner-card h3 {
  margin: 0 0 8px;
  font-size: var(--fs-17);
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--white);
}

.page-about .partner-card p {
  margin: 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--mist);
}

/* ---------- 坚持的做法 ---------- */
.page-about .practice-panel {
  padding: clamp(18px, 3.2vw, 30px);
  border: var(--about-line) solid var(--gold);
  background: var(--paper);
  box-shadow: var(--shadow-hard);
}

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

.page-about .practice-list li {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 10px;
  font-size: var(--fs-17);
  line-height: 1.72;
  color: var(--about-paper-text);
}

.page-about .practice-list li::before {
  content: "—";
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--ink);
}

/* ---------- 结尾引导 ---------- */
.page-about .about-cta {
  margin-top: clamp(20px, 3.5vw, 30px);
  display: grid;
  gap: 18px;
  padding: clamp(18px, 3.2vw, 30px);
  border: var(--about-line) solid var(--cyan);
  background: linear-gradient(135deg, var(--ink-2) 0%, var(--deep) 100%);
  box-shadow: var(--shadow-hard);
}

.page-about .about-cta-text h3 {
  margin: 0 0 10px;
  font-size: clamp(1.15rem, 2.6vw, 1.5rem);
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.015em;
  color: var(--white);
}

.page-about .about-cta-text p {
  margin: 0;
  max-width: 58ch;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-about .about-tail-link {
  margin: clamp(16px, 3vw, 24px) 0 0;
  font-size: var(--fs-14);
  line-height: 1.75;
  color: var(--mist);
}

.page-about .about-tail-link a {
  color: var(--gold);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ---------- 断点 ---------- */
@media (min-width: 640px) {
  .page-about {
    --about-rail: 56px;
  }

  .page-about .shift-cell {
    font-size: var(--fs-12);
    padding: 14px 4px;
  }

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

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

  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
    align-items: end;
  }

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

  .page-about .about-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
  }

  .page-about .about-cta-actions {
    justify-content: flex-end;
  }

  .page-about .about-row {
    gap: clamp(20px, 3vw, 40px);
  }
}

@media (min-width: 1200px) {
  .page-about .about-hero h1 {
    max-width: 20ch;
  }

  .page-about .version-list {
    padding-left: 4px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .shift-cell {
    transition: none;
  }

  .page-about .shift-cell:hover {
    transform: none;
  }
}