/* ===== 品牌档案页专属样式 ===== */
.page-about {
  background-color: var(--paper);
  color: var(--ink);
}

/* 章节编号徽章 */
.about-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.5rem;
  height: 2.5rem;
  padding: 0 0.625rem;
  background: var(--red);
  color: var(--paper);
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.25rem;
  line-height: 1;
  clip-path: polygon(0 0, 100% 0, calc(100% - 0.5rem) 100%, 0 100%);
  margin-bottom: 0.75rem;
}

/* 窄栏侧注 */
.about-aside-note {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 0.875rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--terracotta);
}

@media (min-width: 900px) {
  .page-about .editorial-grid__aside {
    position: sticky;
    top: calc(var(--header-height) + 2rem);
    align-self: start;
  }
}

/* 章节标题强调线 */
.page-about .section-title::after {
  content: "";
  display: block;
  width: 64px;
  height: 4px;
  margin-top: 0.875rem;
  background: linear-gradient(90deg, var(--red), var(--gold));
}

/* ---------- 01 我们是谁 ---------- */
.about-intro__body p {
  font-size: 1.0625rem;
  line-height: 1.8;
  margin-bottom: 1.25rem;
  max-width: 680px;
}

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

.about-trust {
  margin-top: 2.25rem;
  padding: 1.5rem;
  background: var(--paper-dim);
  border-left: 4px solid var(--red);
  max-width: 680px;
}

.about-trust__label {
  display: inline-block;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.8125rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--red);
  margin-bottom: 0.625rem;
}

.about-trust p {
  margin-bottom: 0;
  font-size: 0.9375rem;
  line-height: 1.75;
}

/* ---------- 02 发展历程 ---------- */
.about-milestones {
  color: var(--text-light);
}

.about-milestones .section-title {
  color: var(--paper);
}

.about-timeline {
  position: relative;
  margin-top: 2.5rem;
}

.about-timeline::before {
  content: "";
  position: absolute;
  left: 0.375rem;
  top: 0.5rem;
  bottom: 0.5rem;
  width: 2px;
  background: linear-gradient(to bottom, var(--red), var(--gold));
}

.about-timeline__item {
  position: relative;
  padding-left: 1.75rem;
  margin-bottom: 2rem;
}

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

.about-timeline__marker {
  position: absolute;
  left: 0;
  top: 0.25rem;
  width: 0.875rem;
  height: 0.875rem;
  border-radius: 50%;
  background: var(--gold);
  box-shadow: 0 0 0 4px var(--rock-soft);
}

.about-timeline__card {
  position: relative;
  padding: 1.375rem 1.375rem 1.375rem 1.25rem;
  background: var(--rock-soft);
  border: 1px solid var(--line-light);
  border-radius: var(--radius);
}

.about-timeline__card::before {
  content: "";
  position: absolute;
  left: -0.375rem;
  top: 1.25rem;
  width: 0.75rem;
  height: 0.75rem;
  background: var(--rock-soft);
  border-left: 1px solid var(--line-light);
  border-bottom: 1px solid var(--line-light);
  transform: rotate(45deg);
}

.about-timeline__card h3 {
  margin: 0.625rem 0 0.5rem;
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 800;
  color: var(--paper);
}

.about-timeline__card p {
  margin-bottom: 0;
  font-size: 0.9375rem;
  line-height: 1.7;
}

.about-timeline__card .tag {
  display: inline-block;
}

.about-milestones__visual {
  margin-top: 2.75rem;
  max-width: 360px;
  margin-left: auto;
}

.about-milestones__visual img,
.about-scale__visual img,
.about-mission__visual img {
  width: 100%;
  height: auto;
  display: block;
}

@media (min-width: 960px) {
  .about-timeline {
    padding: 0.5rem 0;
  }

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

  .about-timeline__item {
    width: 50%;
    padding-left: 0;
    padding-right: 2.75rem;
    margin-bottom: 2.5rem;
    text-align: right;
  }

  .about-timeline__item:nth-child(even) {
    margin-left: 50%;
    padding-right: 0;
    padding-left: 2.75rem;
    text-align: left;
  }

  .about-timeline__marker {
    left: auto;
    right: -0.4375rem;
  }

  .about-timeline__item:nth-child(even) .about-timeline__marker {
    right: auto;
    left: -0.4375rem;
  }

  .about-timeline__card::before {
    left: auto;
    right: -0.375rem;
  }

  .about-timeline__item:nth-child(even) .about-timeline__card::before {
    right: auto;
    left: -0.375rem;
  }

  .about-milestones__visual {
    margin-left: 0;
    max-width: 340px;
  }
}

/* ---------- 03 服务规模 ---------- */
.about-scale__body {
  max-width: 640px;
  font-size: 1.0625rem;
  line-height: 1.8;
}

.about-scale__metrics {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 2.25rem;
}

.about-scale__metric {
  position: relative;
  overflow: hidden;
  padding: 1.25rem 1rem 1.375rem;
  background: var(--rock);
  border-radius: var(--radius);
}

.about-scale__metric::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--red), var(--gold));
}

.about-scale__num {
  display: block;
  font-family: var(--font-display);
  font-size: 1.875rem;
  font-weight: 900;
  line-height: 1.1;
  color: var(--gold);
  white-space: nowrap;
}

.about-scale__label {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-light);
}

.about-scale__visual {
  margin-top: 2.5rem;
  max-width: 860px;
}

@media (min-width: 720px) {
  .about-scale__metrics {
    grid-template-columns: repeat(4, 1fr);
  }

  .about-scale__num {
    font-size: 2.25rem;
  }
}

/* ---------- 04 品牌使命 ---------- */
.about-mission {
  color: var(--text-light);
}

.about-mission .section-title {
  color: var(--paper);
}

.about-mission__lead {
  max-width: 640px;
  font-size: 1.0625rem;
  line-height: 1.8;
}

.about-mission__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.875rem;
  margin-top: 2rem;
}

.about-mission__visual {
  margin-top: 2.5rem;
  max-width: 640px;
}

/* ---------- 05 资质与认证 ---------- */
.about-compliance__card {
  padding: 1.5rem;
  background: var(--paper);
  border: 1px solid var(--line-rgba);
  border-left: 4px solid var(--blue);
  border-radius: var(--radius);
  margin-bottom: 1.25rem;
}

.about-compliance__card h3 {
  margin: 0 0 0.625rem;
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 800;
  color: var(--blue);
}

.about-compliance__card p {
  margin: 0;
  font-size: 0.9375rem;
  line-height: 1.75;
}

.about-compliance__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.875rem;
  margin-top: 2rem;
}