.page-about {
  --about-clip: 16px;
  --about-green-dim: rgba(0, 200, 83, 0.08);
  --about-orange-dim: rgba(255, 109, 0, 0.08);
  background: var(--night-bg);
  color: var(--white-off);
  overflow: hidden;
}

.page-about__breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 20px 20px 0;
  font-family: var(--font-num);
  font-size: 13px;
  color: var(--muted-slate);
}

.page-about__crumb-link {
  color: var(--data-blue);
  text-decoration: none;
  transition: color var(--transition);
}

.page-about__crumb-link:hover {
  color: var(--pitch-green);
}

.page-about__crumb-sep {
  color: var(--line-stroke);
}

.page-about__crumb-current {
  color: var(--highlight);
}

/* ---------- 01 品牌宣言 ---------- */
.page-about__manifesto {
  position: relative;
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 48px 20px 64px;
}

.page-about__manifesto::before {
  content: "";
  position: absolute;
  top: 24px;
  right: -5%;
  width: 45%;
  height: 2px;
  background: repeating-linear-gradient(to left, var(--pitch-green) 0 8px, transparent 8px 14px);
  transform: rotate(-12deg);
  opacity: 0.5;
}

.page-about__manifesto-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
}

.page-about__manifesto-copy {
  position: relative;
  padding-left: 20px;
  border-left: 4px solid var(--pitch-green);
}

.page-about__manifesto-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(2.6rem, 8vw, 5rem);
  line-height: 1.04;
  letter-spacing: -0.03em;
  margin: 16px 0 24px;
}

.page-about__manifesto-lead {
  font-family: var(--font-body);
  font-size: clamp(1.05rem, 2vw, 1.35rem);
  line-height: 1.75;
  color: var(--highlight);
  margin-bottom: 20px;
  max-width: 600px;
}

.page-about__manifesto-text {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted-slate);
  max-width: 580px;
}

.page-about__quote {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.2rem, 3vw, 1.5rem);
  line-height: 1.5;
  color: var(--pitch-green);
  border: 0;
  padding: 20px 0 10px;
  margin: 24px 0 0;
  position: relative;
}

.page-about__quote::before {
  content: "“";
  font-family: var(--font-head);
  font-size: 3rem;
  color: var(--energy-orange);
  margin-right: 8px;
  line-height: 0;
  vertical-align: middle;
}

.page-about__manifesto-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}

.page-about__manifesto-visual {
  position: relative;
}

.page-about__manifesto-img {
  width: 100%;
  height: auto;
  max-height: 500px;
  object-fit: cover;
  clip-path: polygon(0 0, calc(100% - 28px) 0, 100% 28px, 100% 100%, 28px 100%, 0 calc(100% - 28px));
  display: block;
}

.page-about__pitch-line {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(90deg, transparent 48%, rgba(255, 255, 255, 0.18) 48%, rgba(255, 255, 255, 0.18) 52%, transparent 52%),
    linear-gradient(0deg, transparent 48%, rgba(255, 255, 255, 0.12) 48%, rgba(255, 255, 255, 0.12) 52%, transparent 52%);
  background-size: 96px 96px;
  mix-blend-mode: screen;
}

/* ---------- 通用章节 ---------- */
.page-about__section {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 72px 20px;
  position: relative;
}

.page-about__section--data {
  background:
    linear-gradient(135deg, transparent 0%, rgba(0, 200, 83, 0.05) 100%);
  border-top: 1px solid var(--line-stroke);
  border-bottom: 1px solid var(--line-stroke);
}

.page-about__section--community {
  background:
    repeating-linear-gradient(-45deg, transparent 0 12px, rgba(255, 255, 255, 0.015) 12px 13px);
}

.page-about__rail-copy {
  margin-bottom: 48px;
  padding-left: 14px;
  border-left: 2px solid var(--energy-orange);
}

.page-about__section-marker {
  font-family: var(--font-num);
  font-size: 12px;
  letter-spacing: 0.35em;
  color: var(--energy-orange);
  margin-bottom: 12px;
  writing-mode: vertical-rl;
  display: inline-block;
  position: absolute;
  transform: translateX(-38px) rotate(180deg);
}

.page-about__section .tqb-title {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.8rem, 5vw, 3rem);
  line-height: 1.16;
  margin: 12px 0 16px;
}

.page-about__section .tqb-lede {
  color: var(--muted-slate);
  font-size: 15px;
  line-height: 1.8;
  max-width: 640px;
}

/* ---------- 02 发展轨迹时间轴 ---------- */
.page-about__timeline {
  margin-top: 48px;
}

.page-about__timeline-item {
  display: grid;
  grid-template-columns: 84px 1fr;
  gap: 16px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line-stroke);
}

.page-about__timeline-meta {
  text-align: right;
}

.page-about__timeline-num {
  font-family: var(--font-num);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 700;
  color: var(--pitch-green);
  display: block;
  letter-spacing: -0.04em;
}

.page-about__timeline-label {
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--muted-slate);
  display: block;
  margin-top: 4px;
}

.page-about__timeline-content {
  min-width: 0;
}

.page-about__timeline-toggle {
  background: transparent;
  border: 0;
  padding: 8px 0 4px;
  width: 100%;
  text-align: left;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.page-about__timeline-title {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: clamp(1.1rem, 3vw, 1.4rem);
  color: var(--highlight);
  transition: color var(--transition);
}

.page-about__timeline-toggle:hover .page-about__timeline-title {
  color: var(--pitch-green);
}

.page-about__timeline-icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  position: relative;
  border: 2px solid var(--energy-orange);
  clip-path: polygon(8px 0, 100% 0, 100% 100%, 8px 100%, 0 50%);
  transition: background-color var(--transition);
}

.page-about__timeline-toggle[aria-expanded="true"] .page-about__timeline-icon {
  background-color: var(--energy-orange);
}

.page-about__timeline-panel {
  padding: 12px 0 4px;
}

.page-about__timeline-panel p {
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.8;
  color: var(--muted-slate);
  margin: 0;
  border-left: 2px solid var(--data-blue);
  padding-left: 16px;
}

.page-about__timeline-panel[hidden] {
  display: none;
}

/* ---------- 03 数据底座 ---------- */
.page-about__data-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 32px;
  margin-top: 48px;
}

.page-about__data-visual {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}

.page-about__data-visual::before {
  content: "";
  position: absolute;
  inset: 8%;
  background: var(--about-green-dim);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 28px), calc(100% - 28px) 100%, 0 100%);
  z-index: 0;
}

.page-about__data-img {
  position: relative;
  z-index: 1;
  width: 100%;
  height: auto;
  max-height: 500px;
  object-fit: contain;
}

.page-about__data-panels {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.page-about__data-panel {
  background: rgba(17, 24, 39, 0.82);
  backdrop-filter: blur(4px);
  border: 1px solid var(--line-stroke);
  /* background already uses tqb-panel, adding page accent */
  box-shadow: -3px 0 0 var(--energy-orange);
}

.page-about__data-panel-title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 15px;
  color: var(--highlight);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin: 0 0 20px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--line-stroke);
}

.page-about__data-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin: 0;
}

.page-about__data-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.page-about__data-item dt {
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--muted-slate);
}

.page-about__data-item dd {
  margin: 0;
}

.page-about__data-unit {
  font-size: 0.55em;
  color: var(--white-off);
  margin-left: 2px;
}

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

.page-about__data-list-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 12px 0;
  border-bottom: 1px dashed var(--line-stroke);
  font-family: var(--font-body);
  font-size: 14px;
}

.page-about__data-list-item:last-child {
  border-bottom: 0;
}

.page-about__data-list-label {
  color: var(--muted-slate);
}

.page-about__data-list-detail {
  font-family: var(--font-num);
  color: var(--highlight);
  font-weight: 500;
  flex-shrink: 0;
}

.page-about__data-footnote {
  margin-top: 40px;
  padding: 18px 20px;
  background: var(--about-orange-dim);
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
}

.page-about__data-footnote p {
  margin: 0;
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.7;
  color: var(--muted-slate);
}

/* ---------- 04 服务本地 ---------- */
.page-about__community-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  margin-top: 40px;
}

.page-about__community-copy {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
}

.page-about__community-block {
  padding: 24px 20px;
  background: rgba(17, 24, 39, 0.7);
  border-left: 4px solid var(--pitch-green);
  clip-path: polygon(0 0, calc(100% - 18px) 0, 100% 18px, 100% 100%, 0 100%);
}

.page-about__community-num {
  font-family: var(--font-num);
  font-size: clamp(2rem, 6vw, 3rem);
  font-weight: 800;
  color: var(--pitch-green);
  display: block;
  letter-spacing: -0.04em;
  margin-bottom: 8px;
}

.page-about__community-text {
  font-family: var(--font-body);
  font-size: 14px;
  line-height: 1.75;
  color: var(--muted-slate);
  margin: 0;
}

.page-about__community-visual {
  position: relative;
}

.page-about__community-img {
  width: 100%;
  height: auto;
  max-height: 400px;
  object-fit: cover;
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 22px), calc(100% - 22px) 100%, 0 100%);
  display: block;
}

.page-about__community-cta {
  margin-top: 48px;
  padding: 28px 24px;
  background: linear-gradient(100deg, rgba(0, 200, 83, 0.1), rgba(0, 176, 255, 0.05));
  border-top: 2px solid var(--energy-orange);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.page-about__community-cta-text {
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 600;
  color: var(--highlight);
  margin: 0;
}

.page-about__community-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

.page-about__text-link {
  font-family: var(--font-body);
  font-size: 14px;
  color: var(--data-blue);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), color var(--transition);
}

.page-about__text-link:hover {
  color: var(--pitch-green);
  border-bottom-color: var(--pitch-green);
}

/* ---------- 响应式：桌面 ---------- */
@media (min-width: 900px) {
  .page-about__breadcrumbs {
    padding-left: 32px;
    padding-right: 32px;
  }

  .page-about__manifesto {
    padding: 72px 48px 96px;
  }

  .page-about__manifesto-layout {
    grid-template-columns: 1.2fr 0.8fr;
    gap: 64px;
    align-items: center;
  }

  .page-about__manifesto-copy {
    padding-left: 30px;
  }

  .page-about__manifesto-visual {
    transform: translateY(8px);
  }

  .page-about__section {
    padding: 96px 48px;
  }

  .page-about__rail-copy {
    padding-left: 22px;
    margin-bottom: 56px;
  }

  .page-about__section-marker {
    transform: translateX(-58px) rotate(180deg);
    font-size: 14px;
  }

  .page-about__timeline {
    margin-top: 0;
    padding-left: 40px;
  }

  .page-about__timeline-item {
    grid-template-columns: 140px 1fr;
    gap: 32px;
    padding: 30px 0;
  }

  .page-about__timeline-num {
    font-size: 2.6rem;
  }

  .page-about__data-layout {
    grid-template-columns: 0.85fr 1.15fr;
    gap: 48px;
    align-items: center;
  }

  .page-about__data-panels {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .page-about__data-panel {
    padding: 28px;
  }

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

  .page-about__community-copy {
    grid-template-columns: 1fr;
  }

  .page-about__community-block {
    padding-left: 32px;
    padding-right: 28px;
  }

  .page-about__community-cta {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
    padding: 32px 36px;
  }
}

@media (max-width: 460px) {
  .page-about__manifesto {
    padding-left: 16px;
    padding-right: 16px;
  }

  .page-about__manifesto-title {
    font-size: 2.2rem;
    word-break: break-word;
  }

  .page-about__data-grid {
    grid-template-columns: 1fr;
  }

  .page-about__timeline-item {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .page-about__timeline-meta {
    text-align: left;
    display: flex;
    gap: 12px;
    align-items: baseline;
  }

  .page-about__timeline-num {
    font-size: 1.6rem;
    display: inline;
  }

  .page-about__timeline-label {
    display: inline;
    margin: 0;
  }
}