.page-about {
  --about-rail: 210px;
  --about-radius: 0;
  background: var(--c-paper);
  color: var(--c-ink);
}

/* ---------------- 首屏 ---------------- */
.page-about .about-hero {
  position: relative;
  background: linear-gradient(148deg, var(--c-blue-dark) 0%, var(--c-blue-deep) 42%, var(--c-blue) 100%);
  color: var(--c-paper);
  padding: calc(var(--header-h) + clamp(30px, 5vw, 66px)) 0 clamp(68px, 9vw, 126px);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - clamp(34px, 5vw, 72px)), 0 100%);
  overflow: hidden;
}

.page-about .about-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(90deg, rgba(199, 208, 217, 0.09) 0 1px, transparent 1px 92px);
  pointer-events: none;
}

.page-about .about-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: clamp(28px, 4vw, 52px);
  align-items: end;
}

.page-about .about-hero-copy {
  min-width: 0;
}

.page-about .about-hero .breadcrumb {
  color: rgba(245, 248, 251, 0.6);
  margin-bottom: clamp(16px, 2.4vw, 26px);
}

.page-about .about-hero .breadcrumb a {
  color: inherit;
}

.page-about .about-hero .breadcrumb a:hover {
  color: var(--c-paper);
}

.page-about .about-hero .eyebrow {
  color: var(--c-silver);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.page-about .about-hero .eyebrow::before {
  content: "";
  width: 28px;
  height: 2px;
  background: var(--c-orange);
}

.page-about .about-hero-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(38px, 6.4vw, 88px);
  line-height: 1.02;
  letter-spacing: -0.035em;
  margin: clamp(14px, 2vw, 22px) 0 0;
  max-width: 14ch;
  color: var(--c-paper);
}

.page-about .about-hero-lede {
  max-width: 58ch;
  margin: clamp(18px, 2.4vw, 28px) 0 0;
  font-size: var(--fs-lead);
  line-height: 1.78;
  color: rgba(245, 248, 251, 0.82);
}

.page-about .about-hero .btn-row {
  margin-top: clamp(24px, 3vw, 36px);
}

.page-about .about-hero .btn--primary {
  background: var(--c-paper);
  border-color: var(--c-paper);
  color: var(--c-blue-dark);
}

.page-about .about-hero-figure {
  margin: 0;
  min-width: 0;
  border: 1px solid rgba(199, 208, 217, 0.3);
  background: rgba(11, 22, 32, 0.24);
}

.page-about .about-hero-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

/* ---------------- 关键数字条 ---------------- */
.page-about .about-figures {
  padding: clamp(26px, 3.4vw, 46px) 0;
  border-bottom: 1px solid var(--line);
}

.page-about .about-figures .stat-num {
  color: var(--c-blue-dark);
}

/* ---------------- 成长阶段 ---------------- */
.page-about .about-timeline {
  position: relative;
}

.page-about .timeline {
  margin-top: clamp(30px, 4vw, 52px);
  display: grid;
  gap: clamp(20px, 3vw, 40px);
}

.page-about .rail-caption {
  display: none;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-tag);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--c-graphite);
  margin: 0 0 12px;
}

.page-about .rail-list {
  list-style: none;
  margin: 0;
  padding: 0 0 6px;
  display: flex;
  gap: 10px;
  overflow-x: auto;
  scrollbar-width: none;
}

.page-about .rail-list::-webkit-scrollbar {
  display: none;
}

.page-about .rail-link {
  display: flex;
  align-items: center;
  gap: 10px;
  white-space: nowrap;
  padding: 10px 14px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--c-graphite);
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.page-about .rail-num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-note);
  color: var(--c-silver);
  transition: color 0.2s ease;
}

.page-about .rail-label {
  font-size: var(--fs-note);
  letter-spacing: 0.02em;
}

.page-about .rail-link:hover {
  border-color: var(--c-blue);
  color: var(--c-blue-dark);
}

.page-about .rail-link[aria-current="true"],
.page-about .rail-link[aria-current="location"] {
  border-color: var(--c-orange);
  color: var(--c-ink);
  font-weight: 600;
}

.page-about .rail-link[aria-current="true"] .rail-num,
.page-about .rail-link[aria-current="location"] .rail-num {
  color: var(--c-orange);
}

.page-about .timeline-track {
  min-width: 0;
}

.page-about .stage {
  position: relative;
  border-top: 1px solid var(--line);
  background: transparent;
}

.page-about .stage:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .stage-head {
  margin: 0;
}

.page-about .stage-trigger {
  width: 100%;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: baseline;
  gap: clamp(12px, 1.8vw, 24px);
  padding: clamp(16px, 2vw, 24px) 0;
  background: none;
  border: 0;
  cursor: pointer;
  text-align: left;
  font: inherit;
  color: inherit;
}

.page-about .stage-index {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-note);
  color: var(--c-silver);
  letter-spacing: 0.04em;
  transition: color 0.2s ease;
}

.page-about .stage[data-open] .stage-index {
  color: var(--c-orange);
}

.page-about .stage-name {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(18px, 2vw, 26px);
  line-height: 1.28;
  letter-spacing: -0.022em;
  color: var(--c-blue-dark);
}

.page-about .stage-trigger:hover .stage-name {
  color: var(--c-blue);
}

.page-about .stage .panel-body-inner {
  max-width: 62ch;
  padding: 0 0 clamp(22px, 2.8vw, 34px);
}

.page-about .stage .panel-body-inner p {
  margin: 0 0 1em;
  color: var(--c-graphite);
  line-height: 1.78;
}

.page-about .stage .panel-body-inner p:last-child {
  margin-bottom: 0;
}

/* ---------------- 技师队伍 ---------------- */
.page-about .about-crew {
  background: var(--c-paper);
}

.page-about .crew-ladder {
  list-style: none;
  margin: clamp(30px, 4vw, 50px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.page-about .crew-level {
  position: relative;
  background: #fff;
  padding: clamp(20px, 2.4vw, 26px) clamp(16px, 1.8vw, 22px) clamp(24px, 3vw, 34px);
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.page-about .crew-level::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--c-silver);
}

.page-about .crew-level:nth-child(2)::before {
  background: #9dbdda;
}

.page-about .crew-level:nth-child(3)::before {
  background: #4d90cc;
}

.page-about .crew-level:nth-child(4)::before {
  background: var(--c-blue);
}

.page-about .crew-level:nth-child(5)::before {
  background: var(--c-orange);
}

.page-about .lv-tag {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-tag);
  letter-spacing: 0.14em;
  color: var(--c-graphite);
  margin: 0 0 12px;
}

.page-about .lv-name {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(16px, 1.4vw, 19px);
  letter-spacing: -0.012em;
  line-height: 1.35;
  color: var(--c-ink);
  margin: 0 0 10px;
}

.page-about .lv-text {
  margin: 0;
  font-size: var(--fs-note);
  line-height: 1.72;
  color: var(--c-graphite);
}

.page-about .crew-foot {
  margin-top: clamp(24px, 3vw, 40px);
  padding-top: clamp(18px, 2.2vw, 26px);
  border-top: 1px solid var(--line);
  display: grid;
  gap: 10px;
}

.page-about .crew-foot-lead {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(17px, 1.5vw, 21px);
  letter-spacing: -0.018em;
  color: var(--c-blue-deep);
}

.page-about .crew-foot-text {
  margin: 0;
  color: var(--c-graphite);
  line-height: 1.78;
  max-width: 72ch;
}

/* ---------------- 质量三道关 ---------------- */
.page-about .about-quality {
  background: var(--c-blue-dark);
  color: var(--c-paper);
  padding: clamp(52px, 7vw, 100px) 0;
  clip-path: polygon(0 0, 100% clamp(20px, 4vw, 52px), 100% 100%, 0 100%);
}

.page-about .about-quality .eyebrow {
  color: var(--c-silver);
}

.page-about .about-quality .section-title {
  color: var(--c-paper);
}

.page-about .quality-grid {
  display: grid;
  gap: clamp(30px, 4vw, 56px);
  align-items: start;
}

.page-about .gate-list {
  list-style: none;
  margin: clamp(26px, 3.2vw, 40px) 0 0;
  padding: 0;
  display: grid;
  gap: clamp(22px, 2.8vw, 32px);
}

.page-about .gate {
  position: relative;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  column-gap: clamp(12px, 1.6vw, 20px);
  padding-left: clamp(14px, 2vw, 22px);
  border-left: 1px solid var(--line-invert);
}

.page-about .gate::before {
  content: "";
  position: absolute;
  left: -1px;
  top: 4px;
  width: 1px;
  height: 22px;
  background: var(--c-orange);
}

.page-about .gate-num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-note);
  color: var(--c-orange-soft);
  line-height: 1.7;
}

.page-about .gate-title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(17px, 1.5vw, 21px);
  letter-spacing: -0.018em;
  line-height: 1.4;
  color: var(--c-paper);
}

.page-about .gate-text {
  grid-column: 1 / -1;
  margin: 10px 0 0;
  color: rgba(245, 248, 251, 0.76);
  line-height: 1.78;
}

.page-about .quality-figure {
  margin: 0;
  border: 1px solid var(--line-invert);
  min-width: 0;
}

.page-about .quality-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.page-about .quality-figure .media-cap {
  padding: 12px 16px;
  border-top: 1px solid var(--line-invert);
  color: rgba(245, 248, 251, 0.68);
  font-size: var(--fs-note);
  line-height: 1.6;
}

/* ---------------- 培训中心 ---------------- */
.page-about .training-grid {
  display: grid;
  gap: clamp(28px, 4vw, 56px);
  align-items: center;
}

.page-about .training-figure {
  position: relative;
  margin: 0;
  border: 1px solid var(--line);
  min-width: 0;
}

.page-about .training-figure::after {
  content: "";
  position: absolute;
  right: -1px;
  bottom: -1px;
  width: clamp(52px, 9vw, 104px);
  height: 6px;
  background: var(--c-orange);
}

.page-about .training-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 14 / 9;
  object-fit: cover;
}

.page-about .training-copy {
  min-width: 0;
}

.page-about .course-list {
  list-style: none;
  margin: clamp(22px, 2.8vw, 34px) 0 0;
  padding: 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about .course-item {
  background: var(--c-paper);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: clamp(12px, 2vw, 22px);
  padding: clamp(14px, 1.8vw, 20px) 0;
}

.page-about .course-num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-note);
  color: var(--c-blue);
  line-height: 1.7;
}

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

.page-about .course-title {
  margin: 0 0 6px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(16px, 1.3vw, 18px);
  letter-spacing: -0.012em;
  color: var(--c-ink);
}

.page-about .course-text {
  margin: 0;
  font-size: var(--fs-note);
  line-height: 1.72;
  color: var(--c-graphite);
}

/* ---------------- 服务做法 ---------------- */
.page-about .about-pledge {
  background: var(--c-mist);
  padding: clamp(52px, 6.5vw, 96px) 0;
}

.page-about .pledge-grid {
  display: grid;
  gap: clamp(28px, 3.6vw, 56px);
  align-items: start;
}

.page-about .pledge-sticky {
  min-width: 0;
}

.page-about .pledge-big {
  margin: clamp(18px, 2.2vw, 26px) 0 0;
  padding-left: clamp(14px, 1.8vw, 22px);
  border-left: 3px solid var(--c-orange);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(22px, 2.6vw, 34px);
  line-height: 1.36;
  letter-spacing: -0.028em;
  color: var(--c-blue-dark);
}

.page-about .pledge-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: clamp(16px, 2.2vw, 26px);
  counter-reset: pledge;
}

.page-about .pledge-item {
  position: relative;
  counter-increment: pledge;
  background: #fff;
  border: 1px solid var(--line);
  padding: clamp(18px, 2.2vw, 28px);
  min-width: 0;
}

.page-about .pledge-item::before {
  content: counter(pledge, decimal-leading-zero);
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-tag);
  letter-spacing: 0.14em;
  color: var(--c-orange);
}

.page-about .pledge-title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(17px, 1.4vw, 20px);
  letter-spacing: -0.018em;
  color: var(--c-blue-dark);
}

.page-about .pledge-item p {
  margin: 0;
  color: var(--c-graphite);
  line-height: 1.78;
}

/* ---------------- 行业参与 ---------------- */
.page-about .industry-grid {
  display: grid;
  gap: clamp(26px, 3.4vw, 48px);
  align-items: start;
}

.page-about .industry-copy {
  min-width: 0;
}

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

.page-about .industry-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 8px;
  padding: clamp(16px, 2vw, 22px) 0;
  border-top: 1px solid var(--line);
}

.page-about .industry-item:last-child {
  border-bottom: 1px solid var(--line);
}

.page-about .industry-tag {
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: var(--fs-tag);
  letter-spacing: 0.14em;
  color: var(--c-blue);
}

.page-about .industry-text {
  margin: 0;
  color: var(--c-graphite);
  line-height: 1.78;
}

/* ---------------- 结尾行动 ---------------- */
.page-about .about-cta {
  background: linear-gradient(120deg, var(--c-blue-deep) 0%, var(--c-blue) 100%);
  color: var(--c-paper);
  padding: clamp(48px, 6.5vw, 92px) 0;
}

.page-about .about-cta-inner {
  max-width: 780px;
}

.page-about .about-cta-title {
  margin: 0;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(26px, 3.4vw, 44px);
  line-height: 1.16;
  letter-spacing: -0.032em;
  color: var(--c-paper);
}

.page-about .about-cta-text {
  margin: clamp(16px, 2vw, 22px) 0 0;
  max-width: 56ch;
  font-size: var(--fs-lead);
  line-height: 1.78;
  color: rgba(245, 248, 251, 0.82);
}

.page-about .about-cta .btn-row {
  margin-top: clamp(24px, 3vw, 34px);
}

/* ---------------- 响应式 ---------------- */
@media (min-width: 760px) {
  .page-about .crew-ladder {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .page-about .crew-foot {
    grid-template-columns: minmax(0, 1fr) minmax(0, 2fr);
    gap: clamp(20px, 3vw, 48px);
    align-items: start;
  }

  .page-about .industry-item {
    grid-template-columns: 128px minmax(0, 1fr);
    gap: clamp(16px, 2vw, 28px);
    align-items: baseline;
  }
}

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

  .page-about .about-hero-grid {
    grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
  }

  .page-about .timeline {
    grid-template-columns: var(--about-rail) minmax(0, 1fr);
    align-items: start;
  }

  .page-about .timeline-rail {
    position: sticky;
    top: calc(var(--header-h) + 32px);
  }

  .page-about .rail-list {
    display: block;
    overflow: visible;
    padding: 0 0 0 22px;
    position: relative;
  }

  .page-about .rail-list::before {
    content: "";
    position: absolute;
    left: 6px;
    top: 8px;
    bottom: 8px;
    width: 1px;
    background: var(--line);
  }

  .page-about .rail-link {
    position: relative;
    background: none;
    border: 0;
    padding: 12px 0;
    color: var(--c-graphite);
  }

  .page-about .rail-link::before {
    content: "";
    position: absolute;
    left: -20px;
    top: 50%;
    width: 9px;
    height: 9px;
    margin-top: -5px;
    background: var(--c-paper);
    border: 1px solid var(--c-silver);
    transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
  }

  .page-about .rail-link[aria-current="true"],
  .page-about .rail-link[aria-current="location"] {
    border: 0;
  }

  .page-about .rail-link[aria-current="true"]::before,
  .page-about .rail-link[aria-current="location"]::before {
    background: var(--c-orange);
    border-color: var(--c-orange);
    transform: scale(1.25);
  }

  .page-about .quality-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  }

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

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

  .page-about .pledge-sticky {
    position: sticky;
    top: calc(var(--header-h) + 40px);
  }

  .page-about .industry-grid {
    grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-about .rail-link,
  .page-about .rail-link::before,
  .page-about .stage-index {
    transition: none;
  }
}