.page-about {
  --about-red-soft: rgba(230, 57, 70, 0.16);
  --about-orange-soft: rgba(244, 162, 97, 0.18);
  --about-rail: linear-gradient(180deg, var(--red) 0%, var(--orange) 45%, var(--green) 100%);
}

/* 页面刊头 */
.page-about .page-header {
  position: relative;
  overflow: hidden;
  padding: 64px 0 104px;
  background: var(--ink);
  color: var(--white);
}

.page-about .page-header::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 52%;
  height: 100%;
  background: var(--about-orange-soft);
  clip-path: polygon(18% 0, 100% 0, 100% 100%, 0 100%);
}

.page-about .page-header::after {
  content: "";
  position: absolute;
  left: -8%;
  right: -8%;
  bottom: -34px;
  height: 64px;
  background: var(--cream);
  transform: skewY(-2deg);
  z-index: 1;
}

.page-about .page-header__inner {
  position: relative;
  z-index: 2;
}

.page-about .breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 48px;
  font-size: 14px;
  color: var(--gray);
}

.page-about .breadcrumb a {
  color: var(--orange);
  text-decoration: none;
  transition: color 0.2s ease;
}

.page-about .breadcrumb a:hover {
  color: var(--red-light);
}

.page-about .page-kicker {
  margin: 0 0 14px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--orange);
}

.page-about .page-title {
  margin: 0;
  max-width: 900px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(34px, 8vw, 76px);
  line-height: 1.02;
  color: var(--white);
}

.page-about .page-intro {
  margin: 18px 0 0;
  max-width: 660px;
  font-size: 17px;
  line-height: 1.75;
  color: var(--cream);
}

/* 基础区块 */
.page-about .about-section {
  position: relative;
  padding: 72px 0;
  background: var(--cream);
}

.page-about .about-section--dark {
  background: var(--ink);
  color: var(--white);
}

.page-about .about-section--red {
  background: var(--red);
  color: var(--white);
}

/* 编号章节标题 */
.page-about .section-heading {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 14px;
  align-items: start;
  margin-bottom: 36px;
}

.page-about .section-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 64px;
  height: 56px;
  margin-top: 4px;
  background: var(--red);
  color: var(--white);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 38px;
  line-height: 1;
  clip-path: polygon(0 0, 100% 0, 86% 100%, 0 100%);
  box-shadow: 5px 5px 0 rgba(230, 57, 70, 0.18);
}

.page-about .section-heading--light .section-index {
  background: var(--orange);
  color: var(--ink);
  box-shadow: 5px 5px 0 rgba(244, 162, 97, 0.2);
}

.page-about .section-title {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(28px, 5vw, 44px);
  line-height: 1.12;
  color: var(--ink);
}

.page-about .section-heading--light .section-title {
  color: var(--white);
}

.page-about .section-desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.5;
  color: var(--gray);
}

.page-about .section-heading--light .section-desc {
  color: rgba(241, 250, 238, 0.72);
}

/* 01 品牌使命 */
.page-about .mission__media {
  margin-bottom: 36px;
}

.page-about .mission__media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  clip-path: polygon(0 0, 94% 0, 100% 14%, 100% 100%, 0 100%);
}

.page-about .mission__grid {
  display: grid;
  gap: 28px;
}

.page-about .mission__lead {
  margin: 0 0 16px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.3;
  color: var(--ink);
}

.page-about .mission__copy p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-2);
}

.page-about .mission__aside {
  padding: 24px;
  background: var(--white);
  border-left: 4px solid var(--red);
  box-shadow: var(--shadow-red);
}

.page-about .panel__kicker {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--red);
}

.page-about .mission__aside h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-size: 20px;
  line-height: 1.25;
  color: var(--ink);
}

.page-about .mission__aside p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-2);
}

/* 02 发展里程碑 */
.page-about .milestones__notice {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 18px;
  margin-bottom: 48px;
  padding: 18px 20px;
  background: var(--ink-2);
  border-left: 3px solid var(--orange);
}

.page-about .milestones__notice p {
  flex: 1 1 260px;
  margin: 0;
  color: var(--cream);
  font-size: 15px;
  line-height: 1.65;
}

.page-about .timeline {
  position: relative;
}

.page-about .timeline__track {
  position: absolute;
  left: 8px;
  top: 12px;
  bottom: 12px;
  width: 2px;
  border-radius: 2px;
  background: var(--about-rail);
}

.page-about .timeline__item {
  position: relative;
  padding-left: 56px;
  margin-bottom: 48px;
}

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

.page-about .timeline__dot {
  position: absolute;
  left: 0;
  top: 20px;
  z-index: 2;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--red);
  border: 4px solid var(--ink);
  box-shadow: 0 0 0 2px var(--red);
  transition: transform 0.2s ease, background-color 0.2s ease, box-shadow 0.2s ease;
}

.page-about .timeline__item:hover .timeline__dot {
  transform: scale(1.3);
  background: var(--orange);
  box-shadow: 0 0 0 3px var(--orange);
}

.page-about .timeline__meta {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.page-about .timeline__year {
  position: relative;
  z-index: 2;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 32px;
  line-height: 1;
  color: var(--orange);
  letter-spacing: 0.04em;
}

.page-about .timeline__watermark {
  position: absolute;
  right: 8px;
  top: -14px;
  z-index: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 72px;
  line-height: 1;
  color: var(--about-red-soft);
  pointer-events: none;
  user-select: none;
}

.page-about .timeline__card {
  position: relative;
  z-index: 1;
  padding: 22px 24px;
  background: var(--white);
  box-shadow: 0 2px 0 rgba(13, 27, 42, 0.05);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.page-about .timeline__card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--red);
}

.page-about .timeline__card::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 52px;
  height: 100%;
  background: repeating-linear-gradient(-45deg, rgba(230, 57, 70, 0.1) 0 8px, transparent 8px 16px);
  clip-path: polygon(26px 0, 100% 0, 100% 100%, 0 100%);
  pointer-events: none;
}

.page-about .timeline__item:hover .timeline__card {
  transform: translateX(6px);
  box-shadow: var(--shadow-red);
}

.page-about .timeline__card h3 {
  margin: 0 0 8px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 20px;
  line-height: 1.2;
  color: var(--ink);
}

.page-about .timeline__card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-2);
}

/* 03 数据团队 */
.page-about .team__grid {
  display: grid;
  gap: 32px;
  margin-bottom: 40px;
}

.page-about .team__media img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  background: var(--ink-2);
}

.page-about .team__content p {
  margin: 0 0 14px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-2);
}

.page-about .data-highlight {
  display: inline;
  padding: 2px 4px;
  background: var(--red);
  color: var(--white);
  font-weight: 700;
  cursor: help;
  text-decoration: underline dotted rgba(255, 255, 255, 0.7);
  text-underline-offset: 3px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.page-about .data-highlight:hover,
.page-about .data-highlight:focus {
  background: var(--ink);
  color: var(--orange);
}

.page-about .team__dept-list {
  margin: 18px 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid rgba(13, 27, 42, 0.08);
}

.page-about .team__dept-list li {
  display: grid;
  grid-template-columns: 46px 1fr;
  column-gap: 12px;
  align-items: center;
  padding: 12px 0;
  border-bottom: 1px solid rgba(13, 27, 42, 0.08);
}

.page-about .team__dept-badge {
  grid-row: span 2;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--red);
  color: var(--white);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  line-height: 1;
}

.page-about .team__dept-badge--orange {
  background: var(--orange);
  color: var(--ink);
}

.page-about .team__dept-badge--green {
  background: var(--green);
  color: var(--white);
}

.page-about .team__dept-list strong {
  font-size: 15px;
  color: var(--ink);
}

.page-about .team__dept-list .team__dept-desc {
  font-size: 13px;
  color: var(--gray);
}

.page-about .stat-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.page-about .stat-card {
  padding: 20px 12px;
  background: var(--white);
  border: 1px solid rgba(13, 27, 42, 0.08);
  text-align: center;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.page-about .stat-card:hover {
  border-color: var(--red);
  box-shadow: 4px 4px 0 rgba(230, 57, 70, 0.12);
}

.page-about .stat-value {
  display: block;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 36px;
  line-height: 1;
  color: var(--red);
}

.page-about .stat-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  color: var(--gray);
}

.page-about .stat-card--orange .stat-value {
  color: var(--orange);
}

.page-about .stat-card--green .stat-value {
  color: var(--green);
}

/* 04 数据与公正性 */
.page-about .integrity__steps {
  display: grid;
  gap: 14px;
  margin-bottom: 28px;
}

.page-about .integrity__step {
  position: relative;
  padding: 24px 20px 24px 74px;
  background: rgba(13, 27, 42, 0.16);
  border-left: 3px solid var(--orange);
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.page-about .integrity__step:hover {
  background: rgba(13, 27, 42, 0.28);
  transform: translateX(4px);
}

.page-about .integrity__num {
  position: absolute;
  left: 18px;
  top: 24px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 30px;
  line-height: 1;
  color: var(--orange);
}

.page-about .integrity__step h3 {
  margin: 0 0 6px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 19px;
  color: var(--white);
}

.page-about .integrity__step p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--cream);
}

.page-about .integrity__note {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 20px;
  background: var(--ink);
  box-shadow: 6px 6px 0 rgba(13, 27, 42, 0.18);
}

.page-about .integrity__note-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  background: var(--orange);
  color: var(--ink);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  line-height: 1;
}

.page-about .integrity__note p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--cream);
}

/* 05 资质认证 */
.page-about .credentials__grid {
  display: grid;
  gap: 16px;
}

.page-about .credential-card {
  padding: 28px 22px;
  background: var(--white);
  border: 1px solid rgba(13, 27, 42, 0.08);
  text-align: center;
  box-shadow: 0 2px 0 rgba(13, 27, 42, 0.04);
  transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.page-about .credential-card:hover {
  border-color: var(--orange);
  box-shadow: var(--shadow-red);
  transform: translateY(-3px);
}

.page-about .credential-card img {
  display: block;
  width: 84px;
  height: 84px;
  margin: 0 auto 16px;
  object-fit: contain;
}

.page-about .credential-card__glyph {
  display: block;
  width: 72px;
  height: 72px;
  margin: 0 auto 16px;
  border-radius: 50%;
  background: var(--cream);
  color: var(--red);
  font-size: 34px;
  line-height: 72px;
  text-align: center;
}

.page-about .credential-card h3 {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 21px;
  color: var(--ink);
}

.page-about .credential-card p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-2);
}

/* 会员中心 */
.page-about .membership {
  position: relative;
  overflow: hidden;
  padding: 72px 0;
  background: var(--ink);
  color: var(--white);
}

.page-about .membership::before {
  content: "";
  position: absolute;
  right: -60px;
  top: -60px;
  width: 220px;
  height: 220px;
  background: var(--red);
  opacity: 0.2;
  transform: rotate(14deg);
  z-index: 0;
}

.page-about .membership::after {
  content: "";
  position: absolute;
  left: -40px;
  bottom: -40px;
  width: 180px;
  height: 180px;
  background: var(--orange);
  opacity: 0.1;
  transform: rotate(-8deg);
  z-index: 0;
}

.page-about .membership__inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 24px;
}

.page-about .membership__kicker {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 14px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--orange);
}

.page-about .membership__copy h2 {
  margin: 0 0 12px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(30px, 5vw, 52px);
  line-height: 1.08;
  color: var(--white);
}

.page-about .membership__copy p {
  margin: 0 0 26px;
  font-size: 16px;
  line-height: 1.75;
  color: var(--cream);
}

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

.page-about .btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 26px;
  border: 2px solid var(--red);
  background: var(--red);
  color: var(--white);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 16px;
  letter-spacing: 0.03em;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.2s ease, border-color 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.page-about .btn:hover {
  background: var(--red-light);
  border-color: var(--red-light);
  box-shadow: 4px 4px 0 rgba(230, 57, 70, 0.32);
  transform: translate(-2px, -2px);
}

.page-about .btn-ghost {
  background: transparent;
  border-color: var(--white);
  color: var(--white);
}

.page-about .btn-ghost:hover {
  background: var(--white);
  border-color: var(--white);
  color: var(--ink);
}

/* 平板及以上 */
@media (min-width: 768px) {
  .page-about .page-header {
    padding: 96px 0 128px;
  }

  .page-about .page-title {
    max-width: 980px;
    font-size: clamp(48px, 7vw, 84px);
  }

  .page-about .page-intro {
    font-size: 18px;
  }

  .page-about .about-section {
    padding: 96px 0;
  }

  .page-about .section-heading {
    grid-template-columns: 76px 1fr;
    gap: 20px;
    margin-bottom: 48px;
  }

  .page-about .section-index {
    width: 76px;
    height: 64px;
    font-size: 46px;
  }

  .page-about .mission__grid {
    grid-template-columns: 1fr 340px;
    gap: 40px;
    align-items: start;
  }

  .page-about .mission__media {
    margin-bottom: 48px;
  }

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

  .page-about .integrity__steps {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .page-about .credentials__grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
  }

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

  .page-about .membership__actions {
    flex-direction: column;
    justify-content: center;
  }
}

/* 桌面端 */
@media (min-width: 1024px) {
  .page-about .team__grid {
    grid-template-columns: 420px 1fr;
    gap: 48px;
    align-items: center;
  }

  .page-about .timeline__item {
    display: grid;
    grid-template-columns: 200px 1fr;
    column-gap: 48px;
    padding-left: 56px;
    margin-bottom: 56px;
  }

  .page-about .timeline__meta {
    margin-bottom: 0;
    align-items: flex-start;
  }

  .page-about .timeline__year {
    font-size: 44px;
  }

  .page-about .timeline__watermark {
    right: auto;
    top: -8px;
    font-size: 84px;
  }

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

  .page-about .integrity__step {
    padding: 26px 22px 26px 60px;
    border-left: 0;
    border-top: 3px solid var(--orange);
  }

  .page-about .integrity__num {
    left: 16px;
    top: 26px;
  }
}