.page-about {
  --about-border-line: rgba(230, 230, 230, 0.14);
  --about-grid-line: rgba(176, 212, 255, 0.05);
  --about-green-glow: rgba(57, 255, 20, 0.12);
  background: var(--deep-blue);
  color: var(--white);
  overflow-x: hidden;
}

/* ===== Hero / 首屏档案区 ===== */
.page-about .about-hero {
  position: relative;
  padding: clamp(32px, 5vw, 56px) 0 clamp(48px, 7vw, 88px);
}

.page-about .about-hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: min(46vw, 620px);
  height: 100%;
  background:
    linear-gradient(135deg, transparent 78%, rgba(57, 255, 20, 0.08) 78%, rgba(57, 255, 20, 0.08) 81%, transparent 81%),
    repeating-linear-gradient(0deg, var(--about-grid-line) 0, var(--about-grid-line) 1px, transparent 1px, transparent 24px),
    radial-gradient(ellipse at 80% 20%, rgba(57, 255, 20, 0.1) 0%, transparent 60%);
  pointer-events: none;
}

.page-about .about-hero-inner {
  position: relative;
  z-index: 1;
}

.page-about .about-hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
  position: relative;
  z-index: 1;
}

.page-about .about-hero-main {
  max-width: 860px;
}

.page-about .about-hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-headline);
  font-size: 13px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--orange-red);
  margin: 0 0 18px;
}

.page-about .about-hero-kicker::before {
  content: "";
  width: 26px;
  height: 2px;
  background: var(--fluorescent-green);
}

.page-about .about-hero-title {
  font-family: var(--font-headline);
  font-style: italic;
  font-weight: 400;
  font-size: clamp(48px, 8vw, 96px);
  line-height: 0.95;
  text-transform: uppercase;
  letter-spacing: 0.01em;
  margin: 0 0 24px;
}

.page-about .about-hero-title span {
  color: var(--fluorescent-green);
}

.page-about .about-hero-lead {
  max-width: 560px;
  font-size: 16px;
  line-height: 1.9;
  color: var(--light-gray);
  margin: 0 0 20px;
}

.page-about .about-hero-lead strong {
  color: var(--fluorescent-green);
  font-weight: 600;
}

.page-about .about-hero-update {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  letter-spacing: 0.05em;
  color: var(--mid-gray);
  margin: 0;
}

.page-about .about-hero-update-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--fluorescent-green);
  box-shadow: 0 0 12px var(--fluorescent-green);
}

.page-about .about-hero-facts {
  position: relative;
  padding: 12px 0 8px 24px;
  border-left: 3px solid var(--fluorescent-green);
  background: linear-gradient(180deg, rgba(57, 255, 20, 0.07) 0%, transparent 100%);
}

.page-about .about-hero-facts-label {
  font-family: var(--font-headline);
  font-size: 13px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mid-gray);
  margin: 0 0 16px;
}

.page-about .about-hero-facts-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px 20px;
  margin: 0;
}

.page-about .about-hero-facts-list div {
  display: flex;
  flex-direction: column;
}

.page-about .about-hero-facts-list div:nth-child(5) {
  grid-column: 1 / -1;
}

.page-about .about-hero-facts-list dt {
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--mid-gray);
}

.page-about .about-hero-facts-list dd {
  margin: 4px 0 0;
  font-family: var(--font-headline);
  font-size: 28px;
  line-height: 1;
  color: var(--fluorescent-green);
}

.page-about .about-hero-note {
  margin: 20px 0 0;
  padding-top: 14px;
  border-top: 1px solid var(--about-border-line);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--mid-gray);
}

/* ===== 通用章节 ===== */
.page-about .about-section {
  padding: clamp(56px, 8vw, 108px) 0;
  position: relative;
}

.page-about .about-section-dark {
  background: var(--navy-black);
  border-top: 1px solid var(--about-border-line);
  border-bottom: 1px solid var(--about-border-line);
}

.page-about .section-head {
  display: flex;
  align-items: baseline;
  gap: 14px;
  margin-bottom: 36px;
}

.page-about .section-index {
  font-family: var(--font-headline);
  font-size: 28px;
  color: var(--orange-red);
  letter-spacing: 0.05em;
}

.page-about .section-title {
  font-family: var(--font-headline);
  font-size: clamp(28px, 4vw, 46px);
  font-weight: 400;
  font-style: italic;
  text-transform: uppercase;
  margin: 0;
}

.page-about .section-line {
  flex: 1;
  height: 1px;
  background: var(--about-border-line);
  align-self: center;
  min-width: 24px;
}

/* ===== 档案夹标签 ===== */
.page-about .about-folder-label {
  border-top: 2px solid var(--fluorescent-green);
  padding-top: 16px;
  max-width: 280px;
}

.page-about .about-folder-label-text {
  font-family: var(--font-headline);
  font-size: 18px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fluorescent-green);
  margin: 0 0 8px;
}

.page-about .about-folder-label p {
  font-size: 13px;
  line-height: 1.75;
  color: var(--mid-gray);
  margin: 0;
}

/* ===== 布局网格 ===== */
.page-about .about-origin-layout,
.page-about .about-system-layout,
.page-about .about-milestone-layout,
.page-about .about-culture-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 36px;
  margin-top: 40px;
}

.page-about .about-origin-content,
.page-about .about-system-content,
.page-about .about-culture-content {
  font-size: 15px;
  line-height: 1.9;
  color: var(--light-gray);
}

.page-about .about-origin-content > p,
.page-about .about-system-content > p,
.page-about .about-culture-content > p {
  margin: 0 0 18px;
}

.page-about .about-origin-lead,
.page-about .about-system-lead,
.page-about .about-culture-lead {
  font-size: 18px;
  line-height: 1.85;
  font-weight: 500;
  color: var(--white);
}

.page-about .about-system-content strong {
  color: var(--fluorescent-green);
  font-weight: 600;
}

/* ===== 图片 ===== */
.page-about .media-frame {
  margin: 28px 0;
}

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

.page-about .about-origin-media {
  max-width: 820px;
}

.page-about .about-system-media {
  margin: 44px 0 0;
}

.page-about .about-culture-media {
  margin: 38px 0 0;
  max-width: 900px;
}

/* ===== 数据统计条 ===== */
.page-about .about-stat-strip {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px 20px;
  border-top: 1px solid var(--about-border-line);
  border-bottom: 1px solid var(--about-border-line);
  padding: 24px 0;
  margin-top: 32px;
}

@media (min-width: 640px) {
  .page-about .about-stat-strip {
    grid-template-columns: repeat(4, 1fr);
  }
}

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

.page-about .about-stat-value {
  font-family: var(--font-headline);
  font-size: 34px;
  line-height: 1;
  color: var(--fluorescent-green);
}

.page-about .about-stat-label {
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--mid-gray);
}

/* ===== 数据流程卡 ===== */
.page-about .about-flow-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  margin: 48px 0 4px;
}

@media (min-width: 720px) {
  .page-about .about-flow-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.page-about .about-flow-card {
  background: rgba(10, 25, 47, 0.85);
  border-left: 4px solid var(--fluorescent-green);
  padding: 22px 24px 22px 26px;
  transform: translateZ(0);
  transition: transform var(--transition), background var(--transition);
}

.page-about .about-flow-card:hover,
.page-about .about-flow-card:focus-visible {
  transform: translateY(-4px);
  background: rgba(57, 255, 20, 0.07);
}

.page-about .about-flow-num {
  font-family: var(--font-headline);
  font-size: 30px;
  line-height: 1;
  color: rgba(57, 255, 20, 0.55);
}

.page-about .about-flow-card h3 {
  margin: 8px 0 6px;
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}

.page-about .about-flow-card p {
  margin: 0;
  font-size: 13px;
  line-height: 1.65;
  color: var(--mid-gray);
}

/* ===== 里程碑时间轴 ===== */
.page-about .about-timeline {
  position: relative;
  display: grid;
  gap: 24px;
  padding-left: 32px;
}

.page-about .about-timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(180deg, var(--fluorescent-green), rgba(57, 255, 20, 0.2));
}

.page-about .timeline-item {
  position: relative;
  outline: none;
}

.page-about .timeline-item::before {
  content: "";
  position: absolute;
  left: -32px;
  top: 10px;
  width: 14px;
  height: 14px;
  border: 2px solid var(--fluorescent-green);
  background: var(--navy-black);
  border-radius: 50%;
  transform: translateX(-3px);
  transition: background var(--transition), box-shadow var(--transition);
}

.page-about .timeline-item:hover::before,
.page-about .timeline-item:focus-visible::before {
  background: var(--fluorescent-green);
  box-shadow: 0 0 14px rgba(57, 255, 20, 0.5);
}

.page-about .timeline-year {
  font-family: var(--font-headline);
  font-size: 28px;
  line-height: 1;
  color: var(--fluorescent-green);
  margin-bottom: 8px;
}

.page-about .timeline-card {
  background: rgba(230, 230, 230, 0.05);
  border: 1px solid var(--about-border-line);
  padding: 18px 20px;
  transition: border-color var(--transition), background var(--transition);
}

.page-about .timeline-card:hover,
.page-about .timeline-item:focus-visible .timeline-card {
  border-color: var(--fluorescent-green);
  background: rgba(57, 255, 20, 0.04);
}

.page-about .timeline-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 3px 8px;
  background: var(--fluorescent-green);
  color: var(--navy-black);
  margin-bottom: 10px;
}

.page-about .timeline-card h3 {
  margin: 0 0 6px;
  font-size: 17px;
  line-height: 1.4;
}

.page-about .timeline-desc {
  color: var(--mid-gray);
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
  max-height: 3em;
  overflow: hidden;
  transition: max-height var(--transition);
}

.page-about .timeline-item:hover .timeline-desc,
.page-about .timeline-item:focus-visible .timeline-desc {
  max-height: 12em;
}

/* ===== 团队角色卡 ===== */
.page-about .about-culture-roles {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin: 36px 0 8px;
}

@media (min-width: 720px) {
  .page-about .about-culture-roles {
    grid-template-columns: repeat(3, 1fr);
  }
}

.page-about .about-role-card {
  position: relative;
  background: var(--deep-blue);
  border: 1px solid var(--about-border-line);
  padding: 22px 20px;
  transition: border-color var(--transition), transform var(--transition), background var(--transition);
}

.page-about .about-role-card::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 34px;
  height: 3px;
  background: var(--orange-red);
  transition: width var(--transition);
}

.page-about .about-role-card:hover,
.page-about .about-role-card:focus-within {
  border-color: var(--fluorescent-green);
  transform: translateY(-4px);
  background: rgba(57, 255, 20, 0.05);
}

.page-about .about-role-card:hover::after,
.page-about .about-role-card:focus-within::after {
  width: 60px;
}

.page-about .about-role-code {
  font-family: var(--font-headline);
  font-size: 13px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--orange-red);
}

.page-about .about-role-card h3 {
  margin: 12px 0 8px;
  font-size: 17px;
  font-weight: 700;
}

.page-about .about-role-card p {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--mid-gray);
}

/* ===== CTA 收束区 ===== */
.page-about .about-cta {
  position: relative;
  overflow: hidden;
  padding: clamp(64px, 8vw, 110px) 0;
  border-top: 1px solid var(--about-border-line);
  background:
    linear-gradient(135deg, transparent 72%, rgba(57, 255, 20, 0.08) 72%, rgba(57, 255, 20, 0.08) 75%, transparent 75%),
    radial-gradient(ellipse at 80% 20%, rgba(57, 255, 20, 0.12) 0%, transparent 55%),
    var(--deep-blue);
}

.page-about .about-cta-inner {
  position: relative;
  z-index: 1;
  text-align: center;
  max-width: 680px;
}

.page-about .about-cta-kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-headline);
  font-size: 14px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--orange-red);
  margin: 0 0 16px;
}

.page-about .about-cta-kicker::before,
.page-about .about-cta-kicker::after {
  content: "";
  width: 22px;
  height: 2px;
  background: var(--fluorescent-green);
}

.page-about .about-cta-title {
  font-family: var(--font-headline);
  font-size: clamp(30px, 4.5vw, 52px);
  font-weight: 400;
  font-style: italic;
  text-transform: uppercase;
  margin: 0 0 18px;
}

.page-about .about-cta-text {
  color: var(--mid-gray);
  font-size: 15px;
  line-height: 1.8;
  margin: 0 auto 32px;
  max-width: 520px;
}

.page-about .about-cta-links {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

/* ===== 桌面端布局扩展 ===== */
@media (min-width: 860px) {
  .page-about .about-hero-grid {
    grid-template-columns: 1.15fr 0.85fr;
    gap: 48px;
    align-items: start;
  }

  .page-about .about-origin-layout,
  .page-about .about-system-layout,
  .page-about .about-milestone-layout,
  .page-about .about-culture-layout {
    grid-template-columns: 240px 1fr;
    gap: 64px;
  }

  .page-about .about-folder-label {
    position: sticky;
    top: 24px;
  }

  .page-about .about-milestone-layout .about-folder-label {
    top: 40px;
  }
}

@media (min-width: 640px) {
  .page-about .about-cta-links {
    flex-direction: row;
    justify-content: center;
    gap: 16px;
  }
}

/* ===== 窄屏修正 ===== */
@media (max-width: 480px) {
  .page-about .about-hero-facts-list {
    grid-template-columns: 1fr;
  }

  .page-about .about-hero-facts-list div:nth-child(5) {
    grid-column: auto;
  }

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

  .page-about .about-flow-card {
    padding: 18px 16px;
  }

  .page-about .about-timeline {
    padding-left: 26px;
  }

  .page-about .timeline-item::before {
    left: -26px;
  }
}