/* ===== page-about 专属样式 ===== */
.page-about {
  position: relative;
  overflow: clip;
  background:
    radial-gradient(1200px 600px at 80% -100px, rgba(0, 230, 138, 0.08), transparent 60%),
    var(--navy-900);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.6;
}

.page-about__watermark {
  position: absolute;
  top: 48px;
  right: -20px;
  z-index: 0;
  font-family: var(--font-sans);
  font-weight: 900;
  font-size: clamp(120px, 30vw, 360px);
  line-height: 0.8;
  letter-spacing: -0.08em;
  color: rgba(245, 247, 250, 0.04);
  pointer-events: none;
  user-select: none;
  white-space: nowrap;
}

.page-about .breadcrumb {
  position: relative;
  z-index: 1;
  padding-top: 20px;
}

/* ===== 页首 ===== */
.page-about__hero {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
  padding-top: 16px;
  padding-bottom: 0;
}

.page-about__hero-main .page-heading__idx {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--accent);
  border: 1px solid var(--line-accent);
  background: rgba(0, 230, 138, 0.08);
  padding: 5px 12px;
  margin-bottom: 20px;
}

.page-about__hero h1 {
  margin: 0 0 18px;
  font-size: clamp(28px, 5.2vw, 58px);
  line-height: 1.14;
  font-weight: 900;
  letter-spacing: -0.03em;
  max-width: 18em;
}

.page-about__accent-text {
  color: var(--accent);
}

.page-about__hero .page-intro {
  max-width: 56ch;
  margin: 0 0 24px;
  color: var(--text-muted);
  font-size: 15px;
}

.page-about__hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 8px;
}

.page-about__hero-stats {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  margin: 0;
  align-self: start;
  border: 1px solid var(--line-strong);
  background: linear-gradient(160deg, rgba(11, 27, 58, 0.8), rgba(5, 13, 26, 0.9));
  box-shadow: 0 18px 40px rgba(5, 13, 26, 0.35);
}

.page-about__hero-stats .stat {
  margin: 0;
  padding: 18px 16px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.page-about__hero-stats .stat:nth-child(2n) {
  border-right: 0;
}

.page-about__hero-stats .stat:nth-last-child(-n+2) {
  border-bottom: 0;
}

.page-about__hero-stats .stat__label {
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

.page-about__hero-stats .data-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(28px, 4.5vw, 40px);
  line-height: 1.15;
  color: var(--accent);
  margin: 6px 0 0;
  margin-inline-start: 0;
}

.page-about__hero-stats .data-num span {
  font-size: 0.5em;
  font-weight: 500;
  color: var(--text-muted);
}

.page-about__bridge {
  grid-column: 1 / -1;
  position: relative;
  height: 130px;
  margin-top: 8px;
  overflow: hidden;
}

.page-about__bridge::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 16px;
  background: linear-gradient(90deg, var(--accent) 0 38%, var(--line-strong) 38% 100%);
  clip-path: polygon(0 22%, 100% 0, 100% 100%, 0 100%);
  opacity: 0.9;
}

.page-about__bridge svg {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* ===== 章节标题通用 ===== */
.page-about .section {
  margin: 0;
}

.page-about__story,
.page-about__milestones,
.page-about__credentials,
.page-about__next {
  position: relative;
  z-index: 1;
  padding-top: 56px;
  padding-bottom: 56px;
}

.page-about__section-head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 28px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.page-about__section-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 13px;
  color: var(--accent);
  border: 1px solid var(--line-accent);
  background: rgba(0, 230, 138, 0.07);
  padding: 5px 10px;
  line-height: 1.2;
  white-space: nowrap;
}

.page-about__section-head .eyebrow {
  margin: 0 0 4px;
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--text-faint);
}

.page-about__section-head h2 {
  margin: 0;
  font-size: clamp(24px, 4vw, 34px);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

/* ===== 品牌故事 ===== */
.page-about__story {
  background: linear-gradient(180deg, rgba(11, 27, 58, 0.25), transparent 100%);
}

.page-about__story-lead {
  margin: 0 0 16px;
  font-size: clamp(18px, 2.4vw, 24px);
  font-weight: 700;
  line-height: 1.4;
}

.page-about__story .grid__item p {
  color: var(--text-muted);
  font-size: 15px;
  line-height: 1.75;
}

.page-about__story .btn {
  margin-top: 16px;
}

.page-about__story-figure {
  margin: 0;
}

.page-about__caption-mono {
  margin: 10px 0 0;
  font-size: 12px;
  color: var(--text-faint);
  letter-spacing: 0.06em;
}

/* ===== 数据理念 ===== */
.page-about__philosophy {
  padding-top: 56px;
  padding-bottom: 56px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background:
    radial-gradient(600px 300px at 85% 0%, rgba(0, 230, 138, 0.1), transparent 70%),
    linear-gradient(120deg, rgba(11, 27, 58, 0.5), rgba(5, 13, 26, 0.3) 70%);
}

.page-about__lead {
  margin: 0 0 6px;
  font-size: clamp(24px, 5vw, 44px);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.page-about__lead-sub {
  margin: 0 0 28px;
  color: var(--text-muted);
  font-size: 15px;
}

.page-about__values {
  display: grid;
  gap: 16px;
}

.page-about__value {
  display: flex;
  flex-direction: column;
  min-height: 170px;
  margin: 0;
  padding: 24px;
  background: linear-gradient(165deg, rgba(11, 27, 58, 0.9), rgba(5, 13, 26, 0.92));
  border: 1px solid var(--line);
  transition: transform var(--ease) 0.25s, border-color var(--ease) 0.25s;
}

.page-about__value:hover {
  transform: translateY(-3px);
  border-color: var(--line-accent);
}

.page-about__value--primary {
  border: none;
  background: linear-gradient(135deg, var(--accent) 0%, rgba(0, 230, 138, 0.72) 100%);
  box-shadow: 0 14px 34px rgba(0, 230, 138, 0.16);
}

.page-about__value--primary:hover {
  transform: translateY(-3px) rotate(-0.5deg);
}

.page-about__value .mono {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
}

.page-about__value--primary .mono,
.page-about__value--primary h3,
.page-about__value--primary p {
  color: var(--navy-900);
}

.page-about__value--primary .mono {
  opacity: 0.75;
}

.page-about__value h3 {
  margin: 12px 0 8px;
  font-size: 17px;
  line-height: 1.35;
  font-weight: 900;
}

.page-about__value p {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-muted);
}

.page-about__philosophy-note {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 32px;
  padding: 18px 22px;
  border-left: 2px solid var(--accent);
  background: rgba(0, 230, 138, 0.06);
}

.page-about__philosophy-note p {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ===== 发展历程 ===== */
.page-about__timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  position: relative;
}

.page-about__timeline::before {
  content: "";
  position: absolute;
  left: 76px;
  top: 14px;
  bottom: 28px;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent), rgba(0, 230, 138, 0.08));
}

.page-about__timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: 64px 24px 1fr;
  padding-bottom: 44px;
}

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

.page-about__timeline-year {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 14px;
  color: var(--accent);
  text-align: right;
  padding-top: 6px;
  line-height: 1;
}

.page-about__timeline-item::after {
  content: "";
  grid-column: 2;
  grid-row: 1 / 3;
  justify-self: center;
  margin-top: 6px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px rgba(0, 230, 138, 0.14);
  z-index: 1;
}

.page-about__timeline-body {
  padding-left: 18px;
  margin-top: -4px;
}

.page-about__timeline-body h3 {
  margin: 0 0 8px;
  font-size: 20px;
  line-height: 1.3;
  font-weight: 900;
}

.page-about__timeline-body p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-muted);
  max-width: 48ch;
}

.page-about__timeline-figure {
  margin: 0;
  position: sticky;
  top: calc(var(--header-h) + 24px);
}

.page-about__timeline-note {
  margin: 12px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-faint);
}

/* ===== 团队与资质 ===== */
.page-about__credentials {
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(11, 27, 58, 0.25), transparent 100%);
}

.page-about__cred-intro {
  row-gap: 24px;
}

.page-about__cred {
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
}

.page-about__cred .mono {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 0.04em;
}

.page-about__cred h3 {
  margin: 8px 0 6px;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 900;
  line-height: 1.15;
}

.page-about__cred p {
  margin: 0;
  font-size: 14px;
  color: var(--text-muted);
  max-width: 48ch;
}

.page-about__cred-intro .img-frame {
  margin: 8px 0 0;
}

.page-about__cred-list {
  list-style: none;
  margin: 48px 0 0;
  padding: 0;
  display: grid;
  gap: 18px;
  grid-template-columns: 1fr;
}

.page-about__cred-card {
  position: relative;
  height: 270px;
  perspective: 1100px;
  cursor: pointer;
  outline: none;
}

.page-about__cred-card .page-about__cred-inner {
  position: absolute;
  inset: 0;
  transform-style: preserve-3d;
  transition: transform 0.65s var(--ease);
}

.page-about__cred-card:hover .page-about__cred-inner,
.page-about__cred-card:focus-visible .page-about__cred-inner,
.page-about__cred-card:active .page-about__cred-inner {
  transform: rotateY(180deg);
}

.page-about__cred-card:focus-visible .page-about__cred-inner {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}

.page-about__cred-face {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  text-align: center;
  padding: 24px 20px;
  border: 1px solid var(--line-strong);
  background: linear-gradient(160deg, rgba(11, 27, 58, 0.92), rgba(5, 13, 26, 0.96));
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.page-about__cred-face h3 {
  margin: 4px 0 0;
  font-size: 20px;
  font-weight: 900;
  line-height: 1.3;
}

.page-about__cred-face p {
  margin: 0;
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.6;
}

.page-about__cred-icon {
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 900;
  line-height: 1;
  color: var(--accent);
}

.page-about__cred-hint {
  position: absolute;
  bottom: 14px;
  left: 0;
  right: 0;
  font-size: 11px;
  color: var(--text-faint);
  letter-spacing: 0.06em;
}

.page-about__cred-back {
  transform: rotateY(180deg);
  border-color: rgba(0, 230, 138, 0.5);
}

.page-about__cred-back p {
  max-width: 32ch;
}

/* ===== 底部行动区 ===== */
.page-about__next {
  padding-top: 48px;
  padding-bottom: 64px;
}

.page-about__next-inner {
  display: grid;
  gap: 24px;
  padding: 28px 24px;
  border: 1px solid var(--line-strong);
  background:
    linear-gradient(120deg, rgba(0, 230, 138, 0.14), rgba(11, 27, 58, 0.4) 55%, rgba(5, 13, 26, 0.6));
  clip-path: polygon(0 0, calc(100% - 28px) 0, 100% 28px, 100% 100%, 0 100%);
}

.page-about__next-inner .eyebrow {
  margin-bottom: 8px;
}

.page-about__next-inner h2 {
  margin: 0 0 12px;
  font-size: clamp(24px, 4vw, 36px);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.page-about__next-inner p {
  margin: 0;
  font-size: 15px;
  color: var(--text-muted);
  max-width: 58ch;
}

.page-about__next-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-self: center;
}

/* ===== 响应式栅格覆盖与桌面布局 ===== */
.page-about .grid__item--span-4,
.page-about .grid__item--span-5,
.page-about .grid__item--span-6,
.page-about .grid__item--span-7 {
  grid-column: 1 / -1;
}

@media (min-width: 640px) {
  .page-about__philosophy-note {
    flex-direction: row;
    align-items: center;
  }
}

@media (min-width: 768px) {
  .page-about__hero {
    grid-template-columns: 7fr 5fr;
    align-items: start;
    padding-top: 24px;
  }

  .page-about__hero-main {
    grid-column: 1;
  }

  .page-about__hero-stats {
    grid-column: 2;
    grid-row: 1;
  }

  .page-about .grid__item--span-4 {
    grid-column: span 4 / span 4;
  }

  .page-about .grid__item--span-5 {
    grid-column: span 5 / span 5;
  }

  .page-about .grid__item--span-6 {
    grid-column: span 6 / span 6;
  }

  .page-about .grid__item--span-7 {
    grid-column: span 7 / span 7;
  }

  .page-about__bridge {
    height: 200px;
  }
}

@media (min-width: 900px) {
  .page-about__cred-list {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ===== 移动端时间线 ===== */
@media (max-width: 767px) {
  .page-about__timeline::before {
    left: 7px;
    top: 8px;
    bottom: 8px;
  }

  .page-about__timeline-item {
    grid-template-columns: 1fr;
    padding-left: 28px;
    border-left: 2px solid var(--line-accent);
    padding-bottom: 36px;
  }

  .page-about__timeline-item::after {
    position: absolute;
    left: -6px;
    top: 8px;
    margin-top: 0;
  }

  .page-about__timeline-year {
    text-align: left;
    margin-bottom: 6px;
  }

  .page-about__timeline-body {
    padding-left: 0;
  }
}