.page-about {
  background: var(--color-paper);
  color: var(--color-ink);
  --about-text-dim: rgba(234, 240, 244, 0.82);
  --about-border-soft: rgba(198, 208, 216, 0.22);
  overflow-x: hidden;
}

.page-about a:focus-visible,
.page-about .btn:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: 2px;
}

.page-about .section {
  padding: clamp(2.5rem, 7vw, 5rem) var(--gap-page);
}

.page-about .container {
  max-width: var(--container-w);
  margin: 0 auto;
}

.page-about .section__label {
  font-family: var(--font-data);
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin: 0 0 0.75rem;
}

.page-about .section__title {
  font-family: var(--font-headline);
  font-weight: 800;
  font-size: var(--font-h2);
  line-height: 1.25;
  color: var(--color-ink);
  margin: 0 0 1rem;
}

.page-about__figcaption {
  font-family: var(--font-data);
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--color-muted);
  margin-top: 0.75rem;
}

.page-about__origin-img,
.page-about__transparent-img,
.page-about__team-img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--color-silver);
}

.page-about__origin-figure,
.page-about__transparent-figure,
.page-about__team-figure {
  margin: 0;
}

/* 英雄区 */
.page-about__hero {
  background:
    radial-gradient(circle at 82% 18%, rgba(255, 107, 53, 0.12), transparent 46%),
    linear-gradient(135deg, var(--color-night) 0%, var(--color-night-deep) 100%);
  color: var(--color-paper);
  padding: calc(var(--header-total) + 2rem) var(--gap-page) 3rem;
  position: relative;
  overflow: hidden;
}

.page-about__hero-grid {
  display: grid;
  gap: 2.5rem;
  max-width: var(--container-w);
  margin: 0 auto;
}

.page-about__hero-breadcrumb {
  margin: 0 0 1.5rem;
}

.page-about__hero-breadcrumb .breadcrumb__list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0;
  margin: 0;
  font-family: var(--font-data);
  font-size: 0.78rem;
  color: rgba(234, 240, 244, 0.7);
}

.page-about__hero-breadcrumb .breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 0.5rem;
  color: rgba(198, 208, 216, 0.5);
}

.page-about__hero-breadcrumb .breadcrumb__link {
  color: var(--color-accent);
  text-decoration: none;
}

.page-about__hero-breadcrumb .breadcrumb__current {
  color: rgba(234, 240, 244, 0.7);
}

.page-about__hero-kicker {
  font-family: var(--font-data);
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin: 0 0 1rem;
}

.page-about__hero-title {
  font-family: var(--font-headline);
  font-weight: 800;
  font-size: var(--font-h1);
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--color-paper);
  margin: 0 0 1.25rem;
}

.page-about__hero-title span {
  display: block;
  font-size: 0.5em;
  font-weight: 600;
  letter-spacing: 0;
  line-height: 1.6;
  color: var(--color-silver);
  margin-top: 0.6rem;
}

.page-about__hero-lead {
  font-family: var(--font-body);
  font-size: clamp(1rem, 1.4vw, 1.125rem);
  line-height: 1.8;
  color: rgba(234, 240, 244, 0.82);
  margin: 0 0 1.5rem;
}

.page-about__hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.page-about__hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.page-about__hero-svg {
  width: 100%;
  max-width: 420px;
  height: auto;
}

@media(max-width: 640px) {
  .page-about__hero-visual {
    display: none;
  }
}

@media(min-width: 768px) {
  .page-about__hero {
    padding: calc(var(--header-total) + 3rem) var(--gap-page) 4rem;
  }

  .page-about__hero-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
    gap: 3rem;
    align-items: center;
  }
}

/* 品牌缘起 */
.page-about__origin {
  background: var(--color-paper);
}

.page-about__origin-grid {
  display: grid;
  gap: 2rem;
  align-items: center;
}

.page-about__origin-copy p {
  font-family: var(--font-body);
  line-height: 1.8;
  color: var(--color-muted);
  margin: 0 0 1rem;
}

.page-about__quote {
  border-left: 4px solid var(--color-accent);
  background: var(--color-silver-light);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0 0;
  color: var(--color-ink);
  font-weight: 600;
}

@media(min-width: 768px) {
  .page-about__origin-grid {
    grid-template-columns: minmax(280px, 0.9fr) minmax(0, 1.1fr);
    column-gap: 3rem;
  }
}

/* 关键里程碑 */
.page-about__timeline-section {
  background:
    linear-gradient(180deg, var(--color-night) 0%, var(--color-night-deep) 100%);
  color: rgba(234, 240, 244, 0.85);
}

.page-about__timeline-section .section__title,
.page-about__network .section__title {
  color: var(--color-paper);
}

.page-about__timeline-head {
  max-width: 76ch;
  margin-bottom: 2.5rem;
}

.page-about__timeline-intro {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--about-text-dim);
  margin-top: 1rem;
}

.page-about__timeline {
  list-style: none;
  padding: 0;
  margin: 0;
  position: relative;
}

.page-about__timeline-item {
  position: relative;
  padding: 0 0 2rem 1.5rem;
  border-left: 2px solid rgba(198, 208, 216, 0.25);
  margin-left: 0.75rem;
}

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

.page-about__timeline-marker {
  display: inline-block;
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--color-paper);
  background: var(--color-night);
  border: 1px solid var(--color-silver);
  border-radius: var(--radius);
  padding: 0.3rem 0.8rem;
  margin-bottom: 0.75rem;
  position: relative;
}

.page-about__timeline-item--current .page-about__timeline-marker {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.page-about__timeline-item::before {
  content: "";
  position: absolute;
  left: -0.38rem;
  top: 1.6rem;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-silver);
  border: 2px solid var(--color-night);
}

.page-about__timeline-item--current::before {
  background: var(--color-accent);
}

.page-about__timeline-panel {
  background: rgba(18, 42, 74, 0.82);
  border: 1px solid rgba(198, 208, 216, 0.2);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: var(--shadow-panel);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.page-about__timeline-panel:hover {
  box-shadow: var(--shadow-panel-hover);
  transform: translateY(-2px);
}

.page-about__timeline-panel h3 {
  font-family: var(--font-headline);
  font-size: 1.15rem;
  color: var(--color-paper);
  margin: 0.75rem 0 0.5rem;
}

.page-about__timeline-panel p {
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.75;
  color: rgba(234, 240, 244, 0.75);
  margin: 0;
}

@media(min-width: 820px) {
  .page-about__timeline::before {
    content: "";
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    transform: translateX(-50%);
    background: linear-gradient(
      180deg,
      rgba(198, 208, 216, 0.1) 0%,
      rgba(255, 107, 53, 0.65) 50%,
      rgba(198, 208, 216, 0.1) 100%
    );
  }

  .page-about__timeline-item {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    grid-template-areas: "panel marker .";
    gap: 1.5rem;
    align-items: center;
    padding: 0;
    border-left: none;
    margin-left: 0;
  }

  .page-about__timeline-item:nth-child(even) {
    grid-template-areas: ". marker panel";
  }

  .page-about__timeline-marker {
    grid-area: marker;
    margin: 0;
    white-space: nowrap;
  }

  .page-about__timeline-panel {
    grid-area: panel;
    max-width: 46ch;
  }
}

/* 数据透明化 */
.page-about__transparent {
  background: var(--color-paper);
}

.page-about__transparent-grid {
  display: grid;
  gap: 2rem;
  align-items: start;
}

.page-about__transparent-intro {
  font-family: var(--font-body);
  color: var(--color-muted);
  line-height: 1.8;
  margin: 0 0 1.5rem;
}

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

.page-about__transparent-row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid rgba(198, 208, 216, 0.35);
}

.page-about__transparent-row:last-child {
  border-bottom: none;
}

.page-about__transparent-num {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: 1rem;
  color: var(--color-accent);
  line-height: 1.8;
  min-width: 2.5rem;
}

.page-about__transparent-row-copy h3 {
  font-family: var(--font-headline);
  font-size: 1.1rem;
  color: var(--color-ink);
  margin: 0 0 0.35rem;
}

.page-about__transparent-row-copy p {
  font-family: var(--font-body);
  color: var(--color-muted);
  margin: 0;
  line-height: 1.7;
  font-size: 0.95rem;
}

@media(min-width: 768px) {
  .page-about__transparent-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(280px, 0.9fr);
    column-gap: 3rem;
  }

  .page-about__transparent-figure {
    position: sticky;
    top: calc(var(--header-total) + 1rem);
  }
}

/* 数据备注与状态面板 */
.page-about__data-note {
  background: var(--color-silver-light);
}

.page-about__data-note-inner {
  display: grid;
  gap: 2rem;
  align-items: center;
}

.page-about__status-panel {
  background: var(--color-night);
  color: var(--color-paper);
  border: 1px solid rgba(198, 208, 216, 0.25);
  border-radius: var(--radius);
  padding: 1.5rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.page-about .status-item__label {
  font-family: var(--font-data);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(198, 208, 216, 0.7);
  display: block;
  margin-bottom: 0.25rem;
}

.page-about .status-item__value {
  font-family: var(--font-data);
  font-size: 1.15rem;
  color: var(--color-paper);
  display: block;
  line-height: 1.4;
}

.page-about .status-item__indicator {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-success);
  display: inline-block;
  margin-top: 0.4rem;
}

.page-about__data-note-copy p {
  font-family: var(--font-body);
  color: var(--color-muted);
  line-height: 1.8;
  margin: 0 0 1rem;
}

.page-about__data-note-copy p:last-child {
  margin-bottom: 0;
}

@media(min-width: 768px) {
  .page-about__data-note-inner {
    grid-template-columns: minmax(280px, 0.85fr) minmax(0, 1.15fr);
  }

  .page-about__status-panel {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1rem;
  }
}

/* 团队与基础设施 */
.page-about__team {
  background: var(--color-paper);
}

.page-about__team-grid {
  display: grid;
  gap: 2rem;
  align-items: center;
}

.page-about__team-copy p:not(.page-about__team-note) {
  font-family: var(--font-body);
  color: var(--color-muted);
  line-height: 1.8;
  margin: 0 0 1rem;
}

.page-about__team-steps {
  list-style: none;
  padding: 0;
  margin: 1rem 0 0;
  display: grid;
  gap: 0.75rem;
}

.page-about__team-step {
  background: var(--color-silver-light);
  border: 1px solid var(--color-silver);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius);
  padding: 1rem;
  transition: box-shadow var(--transition-fast);
}

.page-about__team-step:hover {
  box-shadow: var(--shadow-panel);
}

.page-about__team-step-head {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.page-about__team-step-num {
  font-family: var(--font-data);
  font-weight: 700;
  color: var(--color-accent);
  font-size: 0.85rem;
}

.page-about__team-step-head h3 {
  font-family: var(--font-headline);
  font-size: 1.05rem;
  color: var(--color-ink);
  margin: 0;
}

.page-about__team-step p {
  font-family: var(--font-body);
  font-size: 0.9rem;
  color: var(--color-muted);
  margin: 0.5rem 0 0;
  line-height: 1.6;
}

.page-about__team-note {
  font-family: var(--font-body);
  font-size: 0.95rem;
  color: var(--color-muted);
  line-height: 1.8;
  margin: 1rem 0 0;
}

@media(min-width: 768px) {
  .page-about__team-grid {
    grid-template-columns: minmax(280px, 0.9fr) minmax(0, 1.1fr);
    column-gap: 3rem;
  }
}

/* 资质与合作生态 */
.page-about__credential {
  background: var(--color-silver-light);
}

.page-about__credential-grid {
  display: grid;
  gap: 1.25rem;
  margin-top: 2rem;
}

.page-about__credential-card {
  margin: 0;
  padding: 1.5rem;
  background: var(--color-paper);
  border: 1px solid var(--color-silver);
  border-radius: var(--radius);
  box-shadow: var(--shadow-panel);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.page-about__credential-card:hover {
  box-shadow: var(--shadow-panel-hover);
  transform: translateY(-3px);
}

.page-about__credential-card h3 {
  font-family: var(--font-headline);
  font-size: var(--font-h3);
  color: var(--color-ink);
  margin: 0 0 0.75rem;
  padding-left: 0.875rem;
  border-left: 3px solid var(--color-accent);
}

.page-about__credential-card p {
  font-family: var(--font-body);
  font-size: 0.95rem;
  color: var(--color-muted);
  line-height: 1.7;
  margin: 0;
}

@media(min-width: 700px) {
  .page-about__credential-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* 数据链全景 */
.page-about__network {
  background: var(--color-night);
  color: var(--color-paper);
}

.page-about__network-lead {
  font-family: var(--font-body);
  color: var(--about-text-dim);
  line-height: 1.8;
  max-width: 76ch;
  margin-top: 1rem;
}

.page-about__network-svg {
  width: 100%;
  height: auto;
  margin: 2.5rem 0;
  display: block;
}

.page-about__network-vertical {
  display: none;
  list-style: none;
  margin: 2rem 0;
  padding: 0;
  gap: 1rem;
}

.page-about__network-vertical li {
  background: var(--color-night-deep);
  border: 1px solid rgba(198, 208, 216, 0.2);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius);
  padding: 1rem;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.75rem;
}

.page-about__network-vertical-num {
  font-family: var(--font-data);
  color: var(--color-accent);
  font-weight: 700;
}

.page-about__network-vertical h3 {
  font-family: var(--font-headline);
  color: var(--color-paper);
  margin: 0 0 0.25rem;
  font-size: 1rem;
}

.page-about__network-vertical p {
  font-family: var(--font-body);
  color: rgba(234, 240, 244, 0.78);
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.6;
}

.page-about__network-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

@media(max-width: 700px) {
  .page-about__network-svg {
    display: none;
  }

  .page-about__network-vertical {
    display: grid;
  }
}

/* 收尾联系 */
.page-about__closing {
  background: var(--color-paper);
  border-top: 1px solid var(--color-silver);
}

.page-about__closing-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
}

.page-about__closing p:last-child {
  font-family: var(--font-body);
  color: var(--color-muted);
  line-height: 1.7;
  margin: 0;
  max-width: 64ch;
}