/* 关于我们 V1 · 品牌叙事打磨：对齐首页 Quiet Intelligence，去卡片堆砌感 */
:root {
  --brand: #1e4d91;
  --brand-600: #1769aa;
  --brand-deep: #163a73;
  --brand-deeper: #0f2f5c;
  --brand-ink: #071a2c;
  --cyan: #55b9e8;
  --mist: #f5f8fc;
  --soft: #eef3f9;
  --gray: #5b6b7c;
  --ink-soft: #3d4757;
  --r-lg: 22px;
  --shadow-soft: 0 1px 2px rgba(15, 39, 64, .03), 0 18px 48px rgba(15, 39, 64, .07);
  --ease-out: cubic-bezier(.22, 1, .36, 1);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
::selection { background: #dbeafe; color: #10446f; }
:focus-visible {
  outline: 2px solid var(--brand-600);
  outline-offset: 3px;
}

.about-main { padding-top: 72px; }

/* 眉标：与首页 .kicker 同构 */
.sec-label {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  margin: 0 0 20px;
  font-size: .72rem;
  font-weight: 800;
  letter-spacing: .14em;
  text-transform: uppercase;
  line-height: 1;
  color: var(--brand-600);
}
.sec-label::after {
  content: "";
  flex: 0 0 auto;
  width: 88px;
  height: 2px;
  background: linear-gradient(
    90deg,
    currentColor 0%,
    color-mix(in srgb, currentColor 45%, transparent) 52%,
    transparent 100%
  );
  clip-path: polygon(0 0, 100% 40%, 100% 60%, 0 100%);
}

.sec-h {
  margin: 0 0 28px;
  font-size: clamp(1.65rem, 3.4vw, 2.55rem);
  font-weight: 800;
  letter-spacing: -.028em;
  line-height: 1.22;
  text-wrap: pretty;
}
html[lang="zh-CN"] .sec-h {
  letter-spacing: -.018em;
  line-height: 1.3;
  line-break: strict;
}

.sec-body {
  margin: 0 0 1.05em;
  font-size: 1.05rem;
  line-height: 1.9;
  max-width: 42rem;
  color: var(--ink-soft);
  text-wrap: pretty;
}
html[lang="zh-CN"] .sec-body {
  line-break: strict;
}
.sec-body:last-child { margin-bottom: 0; }

.sec-pull {
  margin: 32px 0 0;
  font-size: clamp(1.12rem, 2.1vw, 1.32rem);
  font-weight: 700;
  line-height: 1.55;
  letter-spacing: -.012em;
  max-width: 40rem;
  color: var(--brand);
  text-wrap: pretty;
}
html[lang="zh-CN"] .sec-pull {
  line-break: strict;
}

.sec-subh {
  margin: 56px 0 28px;
  font-size: clamp(1.2rem, 2.1vw, 1.45rem);
  font-weight: 800;
  letter-spacing: -.02em;
  line-height: 1.35;
  color: var(--brand-900);
}

.prose-stack .sec-body + .sec-body { margin-top: -.15em; }

.reveal {
  opacity: 0;
  transform: translateY(16px);
  filter: blur(2px);
  transition:
    opacity .85s var(--ease-out),
    transform .85s var(--ease-out),
    filter .85s var(--ease-out);
}
.reveal.is-in {
  opacity: 1;
  transform: none;
  filter: none;
}
.reveal-delay-1 { transition-delay: .08s; }
.reveal-delay-2 { transition-delay: .16s; }
.reveal-delay-3 { transition-delay: .24s; }
.reveal-delay-4 { transition-delay: .32s; }

/* ——— 1 · 首屏：左文案；右侧网络作背景图 ——— */
.about-hero {
  position: relative;
  min-height: min(72vh, 700px);
  display: flex;
  align-items: center;
  padding: 104px 0 72px;
  color: #fff;
  background:
    radial-gradient(ellipse 70% 55% at 78% 18%, rgba(85, 185, 232, .22), transparent 58%),
    radial-gradient(ellipse 45% 40% at 12% 88%, rgba(23, 105, 170, .45), transparent 52%),
    linear-gradient(160deg, #061525 0%, #0d2a4f 38%, #1e4d91 72%, #163a73 100%);
  overflow: hidden;
}
.about-hero::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 96px;
  background: linear-gradient(to bottom, transparent, #fff);
  pointer-events: none;
  z-index: 2;
}
/* 网络图：贴右作背景，不占文案格子 */
.about-hero__bg {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(62%, 760px);
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}
.about-hero__bg picture,
.about-hero__bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 70% center;
  display: block;
}
.about-hero__bg::after {
  content: "";
  position: absolute;
  inset: 0;
  /* 仅左侧柔接到文案区，避免把网络图盖死 */
  background: linear-gradient(90deg, rgba(13, 42, 79, .88) 0%, rgba(13, 42, 79, .35) 18%, transparent 42%);
  pointer-events: none;
}
.about-hero__grain {
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  mix-blend-mode: overlay;
  z-index: 0;
}
.about-hero > .wrap {
  position: relative;
  z-index: 1;
}
.about-hero__copy {
  position: relative;
  z-index: 1;
  max-width: 34rem;
  margin-inline: 0;
  padding-bottom: 12px;
  text-align: left;
}
.about-hero .sec-label {
  color: rgba(210, 228, 255, .9);
  margin-bottom: 22px;
}
.about-hero .sec-h {
  color: #fff;
  margin-bottom: 22px;
  font-size: clamp(1.75rem, 3.4vw, 2.55rem);
  text-wrap: balance;
}
html[lang="zh-CN"] .about-hero .sec-h {
  font-size: clamp(1.7rem, 3.2vw, 2.4rem);
  line-height: 1.28;
}
.about-hero .sec-body {
  color: rgba(255, 255, 255, .86);
  font-size: 1.02rem;
  max-width: none; /* 行长跟 .about-hero__copy 34rem */
  line-height: 1.85;
}
.about-hero__en {
  margin: 26px 0 0;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, .14);
  font-size: .9rem;
  font-weight: 500;
  letter-spacing: .01em;
  color: rgba(210, 228, 255, .72);
  line-height: 1.65;
  font-style: italic;
}
/* 跟在文案块末：这是内容底缘，不是 90vh 视口底（否则中间会空一大截） */
.about-explore {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  margin-top: 40px;
  color: rgba(255, 255, 255, .88);
  font-size: .98rem;
  font-weight: 600;
  letter-spacing: 0;
  text-decoration: none;
  transition: color .25s var(--ease-out);
}
.about-explore:hover { color: #fff; }
.about-explore__arrow {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, .38);
  display: grid;
  place-items: center;
  background: rgba(255, 255, 255, .08);
  animation: about-explore-fade 3.2s var(--ease-out) infinite;
}
.about-explore:hover .about-explore__arrow { animation: none; opacity: 1; }
.about-explore__arrow svg { width: 12px; height: 12px; }

@keyframes about-explore-fade {
  0%, 100% { opacity: .55; }
  50% { opacity: 1; }
}

/* ——— 2 · 为什么 ——— */
.about-reason {
  padding: 72px 0 100px;
  background: var(--white);
  position: relative;
}
.about-reason .sec-h { color: var(--brand-900); max-width: none; }
.about-reason .sec-pull { margin-top: 36px; }

/* 拼图定总高：宽随 wrap，高用比例，避免左竖图把整组撑得过高 */
.about-scenes {
  display: grid;
  grid-template-columns: 1.35fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 14px;
  margin-top: 56px;
  aspect-ratio: 2.15 / 1;
  max-height: 440px;
  min-height: 0;
}
.about-scenes figure {
  position: relative;
  margin: 0;
  border-radius: var(--r-lg);
  overflow: hidden;
  background: var(--soft);
  min-height: 0;
  height: 100%;
}
.about-scenes figure:first-child {
  grid-row: 1 / span 2;
}
.about-scenes figure::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(160deg, rgba(7, 26, 44, .08), transparent 45%, rgba(30, 77, 145, .12));
  pointer-events: none;
}
.about-scenes img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.88) contrast(1.02);
  transition: transform 1.4s var(--ease-out), filter .6s;
}
.about-scenes figure:hover img {
  transform: scale(1.03);
  filter: saturate(.95) contrast(1.04);
}
.about-scenes figcaption {
  position: absolute;
  width: 1px; height: 1px;
  overflow: hidden; clip: rect(0,0,0,0);
}

/* ——— 3 · 建设什么 ——— */
.about-build {
  padding: 100px 0;
  background: var(--mist);
}
.about-build .sec-h { color: var(--brand-900); max-width: none; }

/* 角色四列：对齐首页 Why 区圆框线标体系 */
.about-roles {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  margin: 8px 0 48px;
  border-top: 1px solid #d7e2ef;
  border-bottom: 1px solid #d7e2ef;
}
.about-role {
  position: relative;
  text-align: center;
  padding: 36px 20px 32px;
}
.about-role + .about-role::before {
  content: "";
  position: absolute;
  left: 0;
  top: 22%;
  bottom: 22%;
  width: 1px;
  background: #d7e2ef;
}
.about-role__icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 18px;
  border: 1.5px solid var(--brand-600);
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: var(--brand-600);
  background: transparent;
}
.about-role__icon svg {
  width: 26px;
  height: 26px;
  display: block;
  stroke: currentColor;
  fill: none;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.about-role h3 {
  margin: 0 0 10px;
  font-size: 1.12rem;
  font-weight: 800;
  color: var(--brand-900);
  letter-spacing: -.015em;
}
.about-role p {
  margin: 0 auto;
  font-size: .92rem;
  color: var(--gray);
  line-height: 1.7;
  max-width: 15.5rem; /* 对齐首页 .why-card p */
}

.about-chain {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 4px;
  margin: 0 0 18px;
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--brand-900);
  letter-spacing: -.015em;
}
.about-chain span { white-space: nowrap; padding: 0 8px 0 0; }
.about-chain__dot {
  width: 22px;
  height: 1px;
  background: linear-gradient(90deg, var(--brand-600), var(--cyan));
  flex: none;
  opacity: .7;
  border-radius: 0;
}
.about-chain-note {
  margin: 0 0 44px;
  max-width: 34rem;
  font-size: 1rem;
  color: var(--gray);
  line-height: 1.75;
}

.about-graph {
  position: relative;
  margin-top: 8px;
  border-radius: 28px;
  background:
    radial-gradient(ellipse 50% 60% at 50% 50%, rgba(85, 185, 232, .1), transparent 70%),
    #fff;
  border: 1px solid rgba(201, 215, 239, .85);
  padding: 36px 24px 28px;
  overflow: hidden;
  box-shadow: var(--shadow-soft);
}
.about-graph svg { width: 100%; height: auto; display: block; }
.graph-line {
  stroke-dasharray: 5 10;
  animation: graph-dash 22s linear infinite;
}
@keyframes graph-dash {
  to { stroke-dashoffset: -320; }
}
/* 节点光环轻闪；主节点用场景圆图，次节点用线标，不再用裸点 */
.graph-ring {
  fill: none;
  stroke: #55B9E8;
  stroke-width: 1.5;
  opacity: .35;
  transform-box: fill-box;
  transform-origin: center;
}
.graph-ring--pulse { animation: graph-ring 4.2s ease-in-out infinite; }
.graph-ring--pulse2 { animation: graph-ring 4.2s ease-in-out 1.3s infinite; }
.graph-ring--pulse3 { animation: graph-ring 4.2s ease-in-out 2.5s infinite; }
@keyframes graph-ring {
  0%, 100% { opacity: .22; }
  50% { opacity: .75; }
}
.graph-icon {
  fill: none;
  stroke: #1769AA;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.graph-icon--muted { stroke: #8A94A6; }

/* ——— 4 · 相信什么 ——— */
.about-believe {
  padding: 100px 0;
  background: var(--white);
}
.about-believe .sec-h {
  color: var(--brand-900);
  max-width: none;
  margin-bottom: 52px;
}

.believe-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border-top: 1px solid var(--line);
}
.believe-item {
  padding: 36px 36px 36px 0;
  border-bottom: 1px solid var(--line);
}
.believe-item:nth-child(even) {
  padding-left: 36px;
  padding-right: 0;
  border-left: 1px solid var(--line);
}
.believe-item h3 {
  margin: 0 0 12px;
  font-size: 1.14rem;
  font-weight: 800;
  color: var(--brand-900);
  letter-spacing: -.015em;
  line-height: 1.35;
}
.believe-item p {
  margin: 0;
  font-size: .98rem;
  color: var(--ink-soft);
  line-height: 1.85;
}

/* ——— 5 · 共建 ——— */
.about-join {
  position: relative;
  padding: 108px 0 112px;
  background:
    radial-gradient(ellipse 55% 45% at 88% 75%, rgba(85, 185, 232, .14), transparent 55%),
    radial-gradient(ellipse 40% 50% at 10% 20%, rgba(30, 77, 145, .35), transparent 50%),
    linear-gradient(155deg, #061525 0%, #0f2f5c 48%, #1e4d91 100%);
  color: #fff;
  overflow: hidden;
}
.about-join .wrap {
  position: relative;
  z-index: 1;
  /* 比旧 640 略宽：标题按逗号断两行，「真实」不被挤断 */
  max-width: 44rem;
}
.about-join .sec-label { color: rgba(210, 228, 255, .85); }
.about-join .sec-h {
  color: #fff;
  max-width: none;
  word-break: keep-all;
  overflow-wrap: normal;
}
.about-join .sec-body {
  color: rgba(255, 255, 255, .86);
  max-width: 38rem;
}
.about-join__row {
  display: flex;
  align-items: center;
  gap: 22px;
  margin-top: 36px;
  flex-wrap: wrap;
}
.about-join__cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 15px 28px;
  border-radius: 999px;
  background: #fff;
  color: var(--brand-deep);
  font-weight: 800;
  font-size: 1rem;
  line-height: 1.35;
  text-align: center;
  max-width: 100%;
  white-space: normal;
  box-shadow: 0 16px 40px rgba(0, 0, 0, .22);
  transition: transform .3s var(--ease-out), background .2s, box-shadow .3s;
}
.about-join__cta:hover {
  transform: translateY(-2px);
  background: #f7fafc;
  box-shadow: 0 20px 48px rgba(0, 0, 0, .28);
}
.about-join__mascot {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: rgba(255, 255, 255, .95);
  object-fit: cover;
  object-position: center 18%;
  flex: none;
  box-shadow: 0 10px 28px rgba(0, 0, 0, .22);
  border: 2px solid rgba(255, 255, 255, .55);
}

@media (max-width: 980px) {
  .about-hero {
    min-height: auto;
    padding: 88px 0 72px;
  }
  .about-hero__bg {
    width: min(70%, 640px);
    opacity: .85;
  }
  .about-roles {
    grid-template-columns: 1fr 1fr;
  }
  .about-role:nth-child(3),
  .about-role:nth-child(4) {
    border-top: 1px solid #d7e2ef;
  }
  .about-role:nth-child(3)::before { display: none; }
}
@media (max-width: 720px) {
  .about-hero {
    min-height: auto;
    padding: 56px 0 96px;
  }
  .about-hero::after { height: 64px; }
  .about-hero__bg {
    width: 100%;
    opacity: .45;
  }
  .about-hero__bg::after {
    background: linear-gradient(180deg, rgba(13, 42, 79, .75) 0%, rgba(13, 42, 79, .35) 55%, transparent 100%);
  }
  .about-hero__copy { max-width: none; }
  .about-explore { font-size: .92rem; margin-top: 32px; }
  .about-explore__arrow { width: 32px; height: 32px; }
  .about-reason { padding: 48px 0 72px; }
  .about-build,
  .about-believe,
  .about-join { padding: 72px 0; }
  .about-scenes {
    display: flex;
    gap: 10px;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    padding-bottom: 4px;
    margin-top: 40px;
    aspect-ratio: auto;
    max-height: none;
    min-height: 0;
    grid-template-columns: none;
    grid-template-rows: none;
  }
  .about-scenes figure {
    flex: 0 0 78%;
    scroll-snap-align: start;
    aspect-ratio: 4 / 3;
    height: auto;
    min-height: 0;
  }
  .about-scenes figure:first-child {
    grid-row: auto;
  }
  .about-roles {
    grid-template-columns: 1fr 1fr;
    gap: 0;
  }
  .about-role {
    padding: 28px 14px;
  }
  .about-role:nth-child(n+3) { border-top: 1px solid #d7e2ef; }
  .about-role:nth-child(3)::before { display: none; }
  .about-role__icon {
    width: 48px;
    height: 48px;
  }
  .about-role__icon svg {
    width: 22px;
    height: 22px;
  }
  .believe-grid { grid-template-columns: 1fr; }
  .believe-item,
  .believe-item:nth-child(even) {
    padding: 28px 0;
    border-left: 0;
  }
  .about-join__row { gap: 18px; }
  .sec-label::after { width: 56px; }
}
@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    filter: none;
    transition: none;
  }
  .about-explore__arrow,
  .graph-line,
  .graph-ring--pulse,
  .graph-ring--pulse2,
  .graph-ring--pulse3 { animation: none; }
}

/* ——— 阿语 RTL ——— */
[dir="rtl"] .sec-label::after {
  background: linear-gradient(
    270deg,
    currentColor 0%,
    color-mix(in srgb, currentColor 45%, transparent) 52%,
    transparent 100%
  );
  clip-path: polygon(100% 0, 0 40%, 0 60%, 100% 100%);
}
[dir="rtl"] .about-hero__bg {
  right: auto;
  left: 0;
}
[dir="rtl"] .about-hero__bg::after {
  background: linear-gradient(270deg, rgba(13, 42, 79, .88) 0%, rgba(13, 42, 79, .35) 18%, transparent 42%);
}
[dir="rtl"] .about-hero__bg img {
  object-position: 30% center;
}
[dir="rtl"] .about-hero__copy {
  text-align: right;
}
[dir="rtl"] .believe-item {
  padding: 36px 0 36px 36px;
}
[dir="rtl"] .believe-item:nth-child(even) {
  padding-left: 0;
  padding-right: 36px;
  border-left: 0;
  border-right: 1px solid var(--line);
}
@media (max-width: 900px) {
  [dir="rtl"] .believe-item,
  [dir="rtl"] .believe-item:nth-child(even) {
    padding: 28px 0;
    border-right: 0;
  }
}