/* ===== 关于我们页面专属样式 ===== */
.page-about {
  background: var(--color-bg);
  color: var(--color-cream);
  overflow-x: clip;
}

/* 页面题头 */
.page-about .about-masthead {
  padding: 40px 0 36px;
  border-bottom: 1px solid var(--color-line);
}

.page-about .about-masthead h1 {
  font-family: var(--font-display);
  font-size: clamp(34px, 6vw, 64px);
  font-weight: 900;
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 14px 0 18px;
  max-width: 860px;
}

.page-about .about-masthead .lead {
  font-size: clamp(15px, 1.6vw, 18px);
  line-height: 1.75;
  color: var(--color-text-soft);
  max-width: 640px;
  margin: 0;
}

/* 首屏数据条 */
.page-about .about-hero-stats {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-line);
}

.page-about .about-hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--color-line);
}

.page-about .about-stat-item {
  background: var(--color-surface);
  padding: 22px 16px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  min-height: 100px;
}

.page-about .about-stat-num {
  font-family: var(--font-mono);
  font-size: 32px;
  font-weight: 800;
  line-height: 1.05;
  color: var(--color-cream);
}

.page-about .about-stat-unit {
  font-size: 15px;
  font-weight: 700;
  color: var(--color-terra);
  margin-left: 3px;
}

.page-about .about-stat-label {
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--color-text-dim);
}

/* 通用章节 */
.page-about .about-section {
  padding: 64px 0 72px;
  border-bottom: 1px solid var(--color-line);
  position: relative;
}

.page-about .section-header {
  margin-bottom: 24px;
}

.page-about .section-header h2 {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 36px);
  font-weight: 900;
  letter-spacing: -0.01em;
  margin: 0;
}

/* 图片容器 */
.page-about .about-figure-frame {
  position: relative;
  overflow: hidden;
  background: var(--color-surface-2);
  border: 1px solid var(--color-line);
}

.page-about .about-figure-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255, 106, 0, 0.12) 0%, transparent 48%);
  pointer-events: none;
}

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

.page-about .figure-caption {
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-text-dim);
}

/* 我们是谁 */
.page-about .about-who-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
  margin-top: 28px;
}

.page-about .about-who-copy > p {
  font-size: 16px;
  line-height: 1.75;
  color: var(--color-text-soft);
  margin: 0 0 16px;
}

.page-about .about-who-copy blockquote {
  margin: 28px 0 0;
  padding: 4px 0 4px 18px;
  border-left: 3px solid var(--color-terra);
  background: linear-gradient(90deg, rgba(232, 130, 85, 0.06), transparent);
}

.page-about .about-who-copy blockquote p {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--color-cream);
  margin: 0;
}

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

.page-about .about-who-figure .about-figure-frame {
  aspect-ratio: 16 / 10;
}

/* 发展历程 */
.page-about .about-timeline-section {
  background: var(--color-surface);
}

.page-about .about-timeline-intro {
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text-soft);
  max-width: 560px;
  margin: 0 0 24px;
}

.page-about .about-timeline-index {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 16px 0;
  border-top: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
  margin-bottom: 44px;
}

.page-about .about-timeline-index a {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--color-text-soft);
  text-decoration: none;
  border: 1px solid var(--color-moss-dark);
  padding: 4px 10px 3px;
  letter-spacing: 0.04em;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.page-about .about-timeline-index a:hover {
  color: var(--color-terra);
  border-color: var(--color-terra);
  background: rgba(232, 130, 85, 0.08);
}

.page-about .about-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 36px;
  position: relative;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  top: 6px;
  bottom: 6px;
  left: 9px;
  width: 1px;
  background: var(--color-moss-dark);
}

.page-about .about-milestone {
  position: relative;
  padding-left: 40px;
  display: grid;
  gap: 12px;
}

.page-about .about-milestone::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 6px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--color-moss);
  box-shadow: 0 0 0 4px rgba(122, 139, 111, 0.18);
  transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.page-about .about-milestone:hover::before,
.page-about .about-milestone:focus-within::before {
  background: var(--color-terra);
  transform: scale(1.2);
  box-shadow: 0 0 0 6px rgba(232, 130, 85, 0.2), 0 0 14px rgba(255, 106, 0, 0.45);
}

.page-about .about-milestone:has(.about-milestone-details[open])::before {
  background: var(--color-orange);
  box-shadow: 0 0 0 6px rgba(255, 106, 0, 0.16), 0 0 18px rgba(255, 106, 0, 0.5);
}

.page-about .about-milestone-meta {
  display: flex;
  align-items: center;
  gap: 12px;
}

.page-about .about-milestone-version {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--color-moss);
  border: 1px solid var(--color-moss-dark);
  background: rgba(74, 85, 70, 0.2);
  padding: 4px 9px 3px;
  letter-spacing: 0.05em;
  line-height: 1.2;
}

.page-about .about-milestone-phase {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-text-dim);
  text-transform: uppercase;
}

.page-about .about-milestone-card {
  background: var(--color-surface-2);
  border: 1px solid var(--color-line);
  padding: 22px 22px 18px;
  transition: border-color 0.25s ease, box-shadow 0.25s ease, transform 0.25s ease;
}

.page-about .about-milestone:hover .about-milestone-card,
.page-about .about-milestone:focus-within .about-milestone-card {
  border-color: var(--color-moss-dark);
  box-shadow: var(--shadow-sm);
  transform: translateY(-2px);
}

.page-about .about-milestone-card h3 {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  margin: 0 0 8px;
}

.page-about .about-milestone-card > p {
  font-size: 15px;
  line-height: 1.65;
  color: var(--color-text-soft);
  margin: 0;
}

.page-about .about-milestone-details {
  margin-top: 14px;
  border-top: 1px solid var(--color-line);
}

.page-about .about-milestone-details summary {
  list-style: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 14px 0 2px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-terra);
}

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

.page-about .about-milestone-details summary::after {
  content: "+";
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 700;
  color: var(--color-moss);
  transition: transform 0.25s ease;
}

.page-about .about-milestone-details[open] summary::after {
  transform: rotate(45deg);
}

.page-about .about-milestone-details p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--color-text-dim);
  margin: 0;
  padding: 0 0 6px;
  animation: aboutFadeIn 0.25s ease both;
}

@keyframes aboutFadeIn {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* 技术实力 */
.page-about .about-tech-section {
  background: var(--color-bg);
}

.page-about .about-tech-band {
  position: relative;
  overflow: hidden;
  margin-top: 20px;
  background: linear-gradient(145deg, var(--color-blue) 0%, #223245 70%, var(--color-surface-2) 100%);
  border: 1px solid var(--color-line);
  padding: 32px 24px 30px;
}

.page-about .about-tech-band::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 140px;
  height: 140px;
  background: linear-gradient(135deg, transparent 48%, rgba(122, 139, 111, 0.28) 49%, rgba(122, 139, 111, 0.28) 51%, transparent 52%);
  pointer-events: none;
}

.page-about .about-tech-band::after {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(115deg, rgba(255, 255, 255, 0.02) 0px, rgba(255, 255, 255, 0.02) 1px, transparent 1px, transparent 18px);
  pointer-events: none;
}

.page-about .about-tech-stats,
.page-about .about-tech-grid {
  position: relative;
  z-index: 1;
}

.page-about .about-tech-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px 18px;
  margin-bottom: 34px;
}

.page-about .about-tech-stat {
  padding: 4px 0 14px;
  border-bottom: 1px solid rgba(242, 239, 231, 0.14);
}

.page-about .about-tech-num {
  font-family: var(--font-mono);
  font-size: clamp(30px, 4vw, 40px);
  font-weight: 900;
  line-height: 1.1;
  color: var(--color-cream);
  letter-spacing: -0.02em;
}

.page-about .about-tech-unit {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-orange);
  margin-left: 3px;
  letter-spacing: 0;
}

.page-about .about-tech-label {
  display: block;
  font-size: 14px;
  color: var(--color-text-soft);
  margin-top: 6px;
  letter-spacing: 0.02em;
}

.page-about .about-tech-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 30px;
}

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

.page-about .about-tech-figure .about-figure-frame {
  aspect-ratio: 16 / 8;
}

.page-about .about-tech-copy p {
  font-size: 16px;
  line-height: 1.75;
  color: var(--color-text-soft);
  margin: 0 0 20px;
}

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

.page-about .about-tech-list li {
  position: relative;
  padding-left: 26px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--color-text-soft);
}

.page-about .about-tech-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 10px;
  height: 10px;
  border: 2px solid var(--color-moss);
  transform: rotate(45deg);
}

/* 服务人群 */
.page-about .about-audience-intro {
  font-size: 16px;
  line-height: 1.75;
  color: var(--color-text-soft);
  max-width: 640px;
  margin: 0 0 28px;
}

.page-about .about-audience-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  align-items: start;
}

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

.page-about .about-audience-figure .about-figure-frame {
  aspect-ratio: 3 / 2;
}

.page-about .about-audience-cards {
  display: grid;
  gap: 14px;
}

.page-about .about-audience-card {
  background: var(--color-surface);
  border: 1px solid var(--color-line);
  padding: 22px 20px;
  position: relative;
  transition: border-color 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease;
}

.page-about .about-audience-card::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--color-moss-dark);
  transition: background 0.25s ease;
}

.page-about .about-audience-card:hover {
  border-color: var(--color-moss-dark);
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm);
}

.page-about .about-audience-card:hover::before {
  background: var(--color-terra);
}

.page-about .about-audience-stage {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--color-terra);
  margin-bottom: 10px;
}

.page-about .about-audience-card h3 {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 800;
  margin: 0 0 8px;
}

.page-about .about-audience-card p {
  font-size: 15px;
  line-height: 1.65;
  color: var(--color-text-soft);
  margin: 0;
}

/* 加入我们 */
.page-about .about-join-section {
  background: var(--color-surface);
  border-bottom: none;
}

.page-about .about-join-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
  margin-top: 20px;
}

.page-about .about-join-card {
  background: var(--color-surface-2);
  border: 1px solid var(--color-line);
  padding: 30px 24px;
  display: flex;
  flex-direction: column;
}

.page-about .about-join-card-highlight {
  background:
    linear-gradient(135deg, rgba(232, 130, 85, 0.08) 0%, rgba(43, 61, 79, 0.5) 100%),
    var(--color-surface-2);
  border-color: var(--color-moss-dark);
}

.page-about .about-join-card h3 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  margin: 0 0 12px;
}

.page-about .about-join-card p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--color-text-soft);
  margin: 0 0 16px;
}

.page-about .about-contact-list {
  list-style: none;
  margin: 16px 0 20px;
  padding: 0;
  border-top: 1px solid var(--color-line);
}

.page-about .about-contact-list li {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 12px 0;
  border-bottom: 1px solid var(--color-line);
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--color-cream);
  line-height: 1.5;
}

.page-about .about-contact-list .contact-label {
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--color-text-dim);
}

.page-about .about-join-card .btn {
  align-self: flex-start;
  margin-top: auto;
}

.page-about .about-join-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: auto;
  padding-top: 8px;
}

.page-about .about-help-strip {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 24px;
  padding: 20px 22px;
  background: var(--color-bg);
  border-left: 3px solid var(--color-moss);
}

.page-about .about-help-strip p {
  font-size: 15px;
  line-height: 1.6;
  color: var(--color-text-soft);
  margin: 0;
}

.page-about .about-help-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.page-about .about-help-links a {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-terra);
  text-decoration: none;
  position: relative;
  padding-right: 20px;
}

.page-about .about-help-links a::after {
  content: "→";
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  transition: transform 0.2s ease;
}

.page-about .about-help-links a:hover::after {
  transform: translateY(-50%) translateX(3px);
}

/* 桌面端断点 */
@media (min-width: 768px) {
  .page-about .about-hero-stats-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .page-about .about-stat-item {
    padding: 28px 20px;
    min-height: 120px;
  }

  .page-about .about-stat-num {
    font-size: 38px;
  }

  .page-about .about-who-grid {
    grid-template-columns: 1.05fr 0.95fr;
    gap: 48px;
    align-items: center;
  }

  .page-about .about-tech-stats {
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
  }

  .page-about .about-tech-grid {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
    align-items: center;
  }

  .page-about .about-audience-grid {
    grid-template-columns: 0.9fr 1.1fr;
    gap: 40px;
    align-items: center;
  }

  .page-about .about-join-grid {
    grid-template-columns: 1fr 1fr;
    gap: 24px;
  }
}

@media (min-width: 960px) {
  .page-about .about-section {
    padding: 88px 0 96px;
  }

  .page-about .about-timeline {
    gap: 44px;
  }

  .page-about .about-timeline::before {
    left: 50%;
    transform: translateX(-50%);
  }

  .page-about .about-milestone {
    width: calc(50% - 32px);
    padding-left: 0;
    gap: 10px;
  }

  .page-about .about-milestone:nth-child(even) {
    margin-left: calc(50% + 32px);
  }

  .page-about .about-milestone::before {
    left: calc(100% + 27px);
    top: 8px;
  }

  .page-about .about-milestone:nth-child(even)::before {
    left: -38px;
  }
}