.page-about {
  overflow-x: hidden;
}

/* ===== 首屏 ===== */
.page-about__hero {
  position: relative;
  padding-top: var(--space-md);
  padding-bottom: var(--space-xl);
}

.page-about__hero-inner {
  display: grid;
  gap: var(--space-lg);
  margin-top: var(--space-lg);
}

.page-about__hero-copy {
  display: grid;
  gap: var(--space-md);
  align-content: start;
}

.page-about__kicker {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.page-about__title {
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: clamp(2rem, 5vw, 3.4rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  margin: 0;
  color: var(--clr-ink);
}

.page-about__lead {
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--clr-gray);
  max-width: 36em;
  margin: 0;
}

.page-about__hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.page-about__hero-stat {
  display: grid;
  gap: 2px;
  min-width: 120px;
  padding: var(--space-sm) var(--space-md);
  background: var(--clr-deep);
  border-radius: var(--radius-md);
}

.page-about__hero-stat .stat-card__value {
  font-family: var(--font-number);
  font-weight: 700;
  font-size: 1.5rem;
  line-height: 1.2;
  color: #FFFFFF;
}

.page-about__hero-stat .stat-card__label {
  font-family: var(--font-body);
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.7);
}

.page-about__hero-img {
  margin: 0;
}

.page-about__hero-img img,
.page-about__milestone-img img,
.page-about__stats-grid img {
  width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
}

.page-about__scroll-hint {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  margin-top: var(--space-xl);
  text-decoration: none;
  color: var(--clr-gray);
}

.page-about__scroll-line {
  position: relative;
  width: 48px;
  height: 3px;
  background: var(--clr-accent);
  overflow: hidden;
}

.page-about__scroll-line::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--clr-cream);
  transform-origin: left center;
  animation: aboutScroll 2s var(--ease-out) infinite;
}

@keyframes aboutScroll {
  0% {
    transform: scaleX(0);
    transform-origin: left center;
  }
  50% {
    transform: scaleX(1);
    transform-origin: left center;
  }
  51% {
    transform-origin: right center;
  }
  100% {
    transform: scaleX(0);
    transform-origin: right center;
  }
}

/* ===== 使命 ===== */
.page-about__mission {
  background: var(--clr-deep);
  color: var(--clr-cream);
}

.page-about__mission .mono-label {
  color: var(--clr-accent);
}

.page-about__mission .section-title {
  color: #FFFFFF;
}

.page-about__mission-body {
  display: grid;
  gap: var(--space-md);
  align-content: start;
}

.page-about__mission-body p {
  margin: 0;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.8);
}

.page-about__mission-lead {
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 1.25rem;
  line-height: 1.5;
  color: #FFFFFF;
}

/* ===== 里程碑 ===== */
.page-about__milestone {
  background-color: var(--clr-cream);
  background-image: repeating-linear-gradient(
    -35deg,
    rgba(15, 59, 59, 0.04) 0,
    rgba(15, 59, 59, 0.04) 1px,
    transparent 1px,
    transparent 16px
  );
}

.page-about__timeline {
  list-style: none;
  position: relative;
  display: grid;
  gap: var(--space-lg);
  margin: 0;
  padding: 0;
}

.page-about__timeline::before {
  content: "";
  position: absolute;
  left: 10px;
  top: 16px;
  bottom: 16px;
  width: 2px;
  background: linear-gradient(to bottom, var(--clr-accent) 0%, var(--clr-deep) 55%, var(--clr-green) 100%);
}

.page-about__timeline-item {
  position: relative;
  padding-left: 44px;
}

.page-about__timeline-node {
  position: absolute;
  left: 4px;
  top: 10px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--clr-accent);
  border: 3px solid var(--clr-cream);
  box-shadow: 0 0 0 2px var(--clr-accent);
}

.page-about__timeline-node::after {
  content: "";
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  border: 2px solid var(--clr-accent);
  opacity: 0;
  animation: aboutPulse 2.6s var(--ease-out) infinite;
}

@keyframes aboutPulse {
  0% {
    transform: scale(0.6);
    opacity: 0.7;
  }
  70% {
    transform: scale(1.5);
    opacity: 0;
  }
  100% {
    transform: scale(1.5);
    opacity: 0;
  }
}

.page-about__timeline-year {
  font-family: var(--font-number);
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  color: var(--clr-deep);
  text-transform: uppercase;
  margin-bottom: var(--space-xs);
}

.page-about__timeline-card {
  background: #FFFFFF;
  border: 1px solid rgba(15, 59, 59, 0.1);
  border-left: 4px solid var(--clr-accent);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  box-shadow: var(--shadow-sm);
  transition: transform var(--speed-fast) var(--ease-out), box-shadow var(--speed-fast) var(--ease-out);
}

.page-about__timeline-item:nth-child(even) .page-about__timeline-card {
  border-left-color: var(--clr-green);
}

.page-about__timeline-item:hover .page-about__timeline-card {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.page-about__timeline-card h3 {
  margin: 0 0 6px;
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 1.05rem;
  color: var(--clr-ink);
}

.page-about__timeline-card p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--clr-gray);
}

.page-about__milestone-img {
  width: min(760px, 100%);
  margin: var(--space-xl) auto 0;
}

/* ===== 数据与覆盖 ===== */
.page-about__stats-section {
  background: var(--clr-deep);
}

.page-about__stats-section .mono-label {
  color: var(--clr-accent);
}

.page-about__stats-section .section-title {
  color: #FFFFFF;
}

.page-about__stats-section .section-subtitle {
  color: rgba(255, 255, 255, 0.75);
}

.page-about__stats-section .stat-grid {
  gap: var(--space-sm);
}

.page-about__stats-section .stat-card {
  padding: var(--space-md);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
}

.page-about__stats-section .stat-card__value {
  font-family: var(--font-number);
  font-weight: 700;
  font-size: 2rem;
  color: var(--clr-accent);
}

.page-about__stats-section .stat-card__label {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.7);
}

.page-about__stats-grid {
  margin-top: var(--space-lg);
  align-items: center;
}

.page-about__ticker-wrap {
  display: grid;
  gap: var(--space-sm);
  align-content: center;
}

.page-about__ticker-wrap h3 {
  margin: 0;
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 1.1rem;
  color: #FFFFFF;
}

.page-about__ticker {
  overflow: hidden;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 90, 54, 0.35);
  border-radius: var(--radius-md);
  cursor: pointer;
}

.page-about__ticker-inner {
  display: flex;
  width: max-content;
  padding: var(--space-sm) 0;
}

.page-about__ticker-inner span {
  white-space: nowrap;
  margin-right: 2rem;
  font-family: var(--font-number);
  font-size: 0.92rem;
  color: var(--clr-cream);
  animation: aboutTicker 28s linear infinite;
}

.page-about__ticker.is-paused .page-about__ticker-inner span {
  animation-play-state: paused;
}

@keyframes aboutTicker {
  from {
    transform: translateX(0);
  }
  to {
    transform: translateX(-50%);
  }
}

.page-about__ticker-note {
  margin: 0;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.55);
}

/* ===== 技术能力 ===== */
.page-about__tech {
  background: var(--clr-cream);
}

.page-about__tech-grid {
  display: grid;
  gap: var(--space-xl);
  margin-top: var(--space-lg);
}

.page-about__tech-list {
  list-style: none;
  display: grid;
  gap: var(--space-lg);
  align-content: start;
  margin: 0;
  padding: 0;
}

.page-about__tech-item {
  display: grid;
  gap: var(--space-xs);
}

.page-about__tech-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: var(--space-sm);
}

.page-about__tech-head .text-mono {
  font-weight: 700;
  color: var(--clr-accent);
}

.page-about__tech-name {
  font-family: var(--font-headline);
  font-weight: 900;
  color: var(--clr-ink);
}

.page-about__tech-desc {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--clr-gray);
}

.page-about__tech-bars {
  display: grid;
  gap: var(--space-sm);
  margin-top: var(--space-sm);
}

.page-about__tech-bar-row {
  display: grid;
  grid-template-columns: 56px 1fr 40px;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.85rem;
}

.page-about__tech-bar-row .text-mono {
  color: var(--clr-ink);
}

.page-about__tech-bar {
  height: 8px;
  border-radius: 4px;
  background: rgba(15, 59, 59, 0.12);
  overflow: hidden;
}

.page-about__tech-bar span {
  display: block;
  height: 100%;
  border-radius: 4px;
  background: linear-gradient(90deg, var(--clr-deep), var(--clr-accent));
}

.page-about__tech-item--coverage .page-about__tech-bar-row:first-child .page-about__tech-bar span {
  background: linear-gradient(90deg, var(--clr-deep), var(--clr-accent));
}

.page-about__tech-item--coverage .page-about__tech-bar-row:last-child .page-about__tech-bar span {
  background: linear-gradient(90deg, var(--clr-green), var(--clr-wine));
}

.page-about__tech-aside {
  min-width: 0;
}

.page-about__tech-card {
  position: relative;
  display: grid;
  gap: var(--space-sm);
  align-content: start;
  overflow: hidden;
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  background: var(--clr-indigo);
  color: #FFFFFF;
}

.page-about__tech-card::after {
  content: "";
  position: absolute;
  right: -40px;
  bottom: -40px;
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: rgba(255, 90, 54, 0.28);
}

.page-about__tech-card h3 {
  margin: 0;
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 1.25rem;
  color: #FFFFFF;
}

.page-about__tech-card p {
  position: relative;
  z-index: 1;
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.85);
}

.page-about__tech-card .btn {
  position: relative;
  z-index: 1;
  justify-self: start;
}

/* ===== 资质与认证 ===== */
.page-about__cert {
  background: var(--clr-cream);
  border-top: 1px solid rgba(15, 59, 59, 0.08);
}

.page-about__cert-grid {
  display: grid;
  gap: var(--space-md);
  margin-top: var(--space-lg);
}

.page-about__cert-item {
  display: grid;
  gap: var(--space-xs);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  background: #FFFFFF;
  border-top: 4px solid var(--clr-accent);
  box-shadow: var(--shadow-sm);
  transition: transform var(--speed-fast) var(--ease-out), box-shadow var(--speed-fast) var(--ease-out);
}

.page-about__cert-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.page-about__cert-item:nth-child(2) {
  border-top-color: var(--clr-green);
}

.page-about__cert-item:nth-child(3) {
  border-top-color: var(--clr-wine);
}

.page-about__cert-item .mono-label {
  color: var(--clr-accent);
}

.page-about__cert-item h3 {
  margin: 0;
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 1.05rem;
  color: var(--clr-ink);
}

.page-about__cert-item p {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--clr-gray);
}

/* ===== 延伸入口 ===== */
.page-about__connect-card {
  display: grid;
  gap: var(--space-lg);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  background: var(--clr-deep);
  color: #FFFFFF;
}

.page-about__connect-card .mono-label {
  color: var(--clr-accent);
}

.page-about__connect-card h2 {
  margin: 4px 0 0;
  font-family: var(--font-headline);
  font-weight: 900;
  font-size: 1.5rem;
  color: #FFFFFF;
}

.page-about__connect-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.page-about__connect-card .btn--ghost {
  border-color: rgba(255, 255, 255, 0.45);
  color: #FFFFFF;
}

.page-about__connect-card .btn--ghost:hover {
  border-color: #FFFFFF;
  background: rgba(255, 255, 255, 0.08);
}

/* ===== 桌面增强 ===== */
@media (min-width: 860px) {
  .page-about__timeline {
    gap: var(--space-xl);
  }

  .page-about__timeline::before {
    left: 50%;
    transform: translateX(-50%);
  }

  .page-about__timeline-item {
    width: 50%;
    padding-left: 0;
    padding-right: 48px;
  }

  .page-about__timeline-item:nth-child(even) {
    margin-left: 50%;
    padding-right: 0;
    padding-left: 48px;
  }

  .page-about__timeline-node {
    left: auto;
    right: -7px;
  }

  .page-about__timeline-item:nth-child(even) .page-about__timeline-node {
    right: auto;
    left: -7px;
  }

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

  .page-about__timeline-item:nth-child(even) .page-about__timeline-year {
    text-align: left;
  }
}

@media (min-width: 900px) {
  .page-about__hero {
    padding-top: var(--space-xl);
  }

  .page-about__hero-inner {
    grid-template-columns: 58% 42%;
    align-items: center;
  }

  .page-about__hero-stats {
    gap: var(--space-md);
  }

  .page-about__scroll-hint {
    margin-top: var(--space-2xl);
  }

  .page-about__tech-grid {
    grid-template-columns: 1.2fr 0.8fr;
    align-items: start;
  }

  .page-about__cert-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .page-about__connect-card {
    grid-template-columns: 1fr auto;
    align-items: center;
    padding: var(--space-xl);
  }
}