/* ============================================================
   关于我们（About）— 顶级编辑设计
   深墨 + 暖金 · 留白 · 排版 · 滚动渐显
   ============================================================ */
:root{
  --ab-ink:#15233B;
  --ab-ink-2:#27374F;
  --ab-body:#4C5767;
  --ab-muted:#8A93A2;
  --ab-gold:#B0894F;
  --ab-gold-soft:#C9A86A;
  --ab-bg:#FFFFFF;
  --ab-bg-alt:#F7F4EF;
  --ab-line:#EAE3D8;
  --ab-orange:#FF5B00;
  --ab-orange-dark:#E54F00;
  --ab-serif:Georgia,"Times New Roman","Songti SC","STSong",serif;
  --ab-sans:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei","Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}

/* ---------- 通用 ---------- */
/* 所有区块上下留白严格一致（白/灰同值）；色块因底色差在视觉上会显空，
   因此整体取值比白底页偏紧，观感均衡 */
.ab-section{padding:clamp(56px,7vw,92px) 0}
.bg-alt{background:var(--ab-bg-alt)}
.ab-eyebrow{
  display:inline-flex;align-items:center;
  font-family:var(--ab-sans);
  font-size:.78rem;font-weight:600;letter-spacing:.22em;text-transform:uppercase;
  color:var(--ab-gold);margin:0 0 16px;
}
.ab-eyebrow::before{
  content:"";width:30px;height:1px;background:var(--ab-gold);
  margin-right:14px;display:inline-block;vertical-align:middle;opacity:.8;
}
.ab-eyebrow--light{color:var(--ab-gold-soft)}
.ab-eyebrow--light::before{background:var(--ab-gold-soft)}
.ab-h2{
  font-family:var(--ab-sans);
  font-size:clamp(1.7rem,3.2vw,2.5rem);font-weight:700;line-height:1.2;
  color:var(--ab-ink);margin:0;letter-spacing:-.01em;
}
.ab-sec-head{max-width:760px;margin:0 auto clamp(36px,5vw,60px);text-align:center}
.ab-sec-head .ab-eyebrow{justify-content:center}
.ab-sec-head .ab-eyebrow::before{margin-right:14px}

/* ---------- HERO ---------- */
.ab-hero{
  position:relative;display:flex;align-items:center;justify-content:center;
  min-height:84vh;padding:140px 0 90px;
  color:#fff;text-align:center;
  background:
    radial-gradient(120% 120% at 50% 0%, #1E3050 0%, #15233B 55%, #0E1828 100%);
  background-size:cover;background-position:center;
  overflow:hidden;
}
.ab-hero::after{
  /* 底部柔和过渡，避免与下一区块硬切 */
  content:"";position:absolute;left:0;right:0;bottom:0;height:120px;
  background:linear-gradient(to bottom,transparent,var(--ab-bg));
}
.ab-hero__inner{position:relative;z-index:2;max-width:900px}
.ab-hero__title{
  font-family:var(--ab-serif);
  font-size:clamp(2.3rem,5.4vw,4.2rem);font-weight:500;line-height:1.18;
  margin:0 auto 22px;max-width:14em;white-space:pre-line;
  color:#fff;text-shadow:0 2px 24px rgba(0,0,0,.45);
}
.ab-hero__sub{
  font-family:var(--ab-sans);
  font-size:clamp(1rem,1.6vw,1.18rem);line-height:1.9;color:rgba(255,255,255,.82);
  max-width:620px;margin:0 auto;
}
.ab-hero__cue{
  margin-top:54px;font-size:.74rem;letter-spacing:.2em;color:rgba(255,255,255,.6);
  text-transform:uppercase;
}
.ab-hero__cue i{
  display:block;width:1px;height:38px;margin:14px auto 0;
  background:linear-gradient(to bottom,var(--ab-gold-soft),transparent);
  animation:ab-cue 2.2s ease-in-out infinite;
}
@keyframes ab-cue{0%,100%{transform:scaleY(.6);opacity:.4}50%{transform:scaleY(1);opacity:1}}

/* ---------- 我们是谁 ---------- */
.ab-story__grid{
  display:grid;grid-template-columns:.85fr 1.15fr;gap:clamp(32px,6vw,72px);
  align-items:start;
}
.ab-story__aside{position:sticky;top:110px}
.ab-story__aside .ab-h2{
  font-family:var(--ab-serif);font-weight:500;font-size:clamp(1.8rem,3.4vw,2.7rem);
  line-height:1.3;color:var(--ab-ink);
}
.ab-para{
  font-family:var(--ab-sans);font-size:1.06rem;line-height:1.95;color:var(--ab-body);
  margin:0 0 20px;
}
.ab-para:first-child{font-size:1.16rem;color:var(--ab-ink-2)}

/* ---------- 理念 ---------- */
.ab-philo__grid{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}
.ab-philo__card{
  position:relative;padding:38px 30px 34px;background:#fff;
  border:1px solid var(--ab-line);border-radius:18px;overflow:hidden;
  transition:transform .35s ease,box-shadow .35s ease,border-color .35s ease;
}
.ab-philo__card:hover{transform:translateY(-6px);box-shadow:0 20px 44px rgba(21,35,59,.10);border-color:var(--ab-gold-soft)}
.ab-philo__no{
  font-family:var(--ab-serif);font-size:2.6rem;line-height:1;color:var(--ab-gold);
  opacity:.85;display:block;margin-bottom:18px;
}
.ab-philo__title{font-family:var(--ab-sans);font-size:1.22rem;font-weight:700;color:var(--ab-ink);margin:0 0 10px}
.ab-philo__desc{font-family:var(--ab-sans);font-size:.98rem;line-height:1.8;color:var(--ab-body);margin:0}

/* ---------- 承诺 ---------- */
.ab-values__grid{display:grid;grid-template-columns:repeat(4,1fr);gap:30px}
.ab-value{padding:6px 4px}
.ab-value__icon{
  display:flex;align-items:center;justify-content:center;
  width:60px;height:60px;border-radius:50%;
  background:rgba(176,137,79,.10);color:var(--ab-gold);
  margin-bottom:20px;
}
.ab-value__icon svg{width:30px;height:30px}
.ab-value__title{font-family:var(--ab-sans);font-size:1.18rem;font-weight:700;color:var(--ab-ink);margin:0 0 10px}
.ab-value__desc{font-family:var(--ab-sans);font-size:.96rem;line-height:1.8;color:var(--ab-body);margin:0}

/* ---------- 历程时间线 ---------- */
.ab-timeline{list-style:none;margin:0 auto;padding:0;max-width:820px;border-left:1px solid var(--ab-line)}
.ab-tl__item{position:relative;padding:0 0 40px 42px}
.ab-tl__item:last-child{padding-bottom:0}
.ab-tl__item::before{
  content:"";position:absolute;left:-7px;top:4px;width:13px;height:13px;border-radius:50%;
  background:var(--ab-gold);box-shadow:0 0 0 5px rgba(176,137,79,.16);
}
.ab-tl__tag{
  display:inline-block;font-family:var(--ab-sans);font-size:.74rem;font-weight:700;letter-spacing:.12em;
  color:var(--ab-gold);background:rgba(176,137,79,.12);
  padding:4px 12px;border-radius:999px;margin-bottom:12px;
}
.ab-tl__title{font-family:var(--ab-sans);font-size:1.2rem;font-weight:700;color:var(--ab-ink);margin:0 0 8px}
.ab-tl__desc{font-family:var(--ab-sans);font-size:1rem;line-height:1.85;color:var(--ab-body);margin:0}

/* ---------- 数据亮点 ---------- */
.ab-stats__grid{display:grid;grid-template-columns:repeat(4,1fr);gap:34px;max-width:960px;margin:0 auto;text-align:center}
.ab-stat{
  padding:30px 12px;border:1px solid var(--ab-line);border-radius:14px;
  background:#fff;transition:transform .35s ease,box-shadow .35s ease,border-color .35s ease;
}
.ab-stat:hover{transform:translateY(-6px);border-color:var(--ab-gold-soft);box-shadow:0 18px 40px rgba(21,35,59,.10)}
.ab-stat__num{font-family:var(--ab-serif);font-size:clamp(2rem,3.4vw,2.7rem);line-height:1;color:var(--ab-gold);margin:0 0 12px}
.ab-stat__label{font-family:var(--ab-sans);font-size:.95rem;letter-spacing:.06em;color:var(--ab-body);margin:0}

/* ---------- 资质证书 ---------- */
.ab-certs__grid{display:grid;grid-template-columns:repeat(4,1fr);gap:26px}
.ab-cert{margin:0;text-align:center}
.ab-cert__pic{
  aspect-ratio:3/4;background:#fff;border:1px solid var(--ab-line);border-radius:12px;
  padding:16px;display:flex;align-items:center;justify-content:center;overflow:hidden;
  box-shadow:0 10px 26px rgba(21,35,59,.06);
  transition:transform .35s ease,box-shadow .35s ease,border-color .35s ease;
}
.ab-cert:hover .ab-cert__pic{
  transform:translateY(-6px);border-color:var(--ab-gold-soft);
  box-shadow:0 18px 40px rgba(21,35,59,.12);
}
.ab-cert__pic img{max-width:100%;max-height:100%;object-fit:contain;display:block}
.ab-cert__name{font-family:var(--ab-sans);font-size:1rem;font-weight:600;color:var(--ab-ink);margin:18px 0 0}
.ab-cert__desc{font-family:var(--ab-sans);font-size:.88rem;line-height:1.7;color:var(--ab-body);margin:6px 0 0}

/* ---------- CTA ---------- */
.ab-cta{
  background:radial-gradient(120% 140% at 50% 0%,#1E3050 0%,#15233B 60%,#0E1828 100%);
  color:#fff;padding:clamp(64px,8vw,104px) 0;text-align:center;
}
.ab-cta__inner{max-width:720px}
.ab-cta .ab-eyebrow{justify-content:center}
.ab-cta .ab-eyebrow::before{background:var(--ab-gold-soft)}
.ab-cta__title{
  font-family:var(--ab-serif);font-weight:500;font-size:clamp(1.9rem,4vw,3rem);
  line-height:1.25;margin:0 0 18px;color:#fff;
}
.ab-cta__desc{font-family:var(--ab-sans);font-size:1.06rem;line-height:1.9;color:rgba(255,255,255,.78);margin:0 auto 34px;max-width:560px}
.ab-cta__btn{
  display:inline-block;font-family:var(--ab-sans);font-size:1.02rem;font-weight:700;
  color:#fff;background:var(--ab-orange);padding:16px 42px;border-radius:999px;
  text-decoration:none;transition:background .25s ease,transform .25s ease,box-shadow .25s ease;
  box-shadow:0 12px 30px rgba(255,91,0,.32);
}
.ab-cta__btn:hover{background:var(--ab-orange-dark);transform:translateY(-2px);box-shadow:0 16px 38px rgba(255,91,0,.40)}

/* ---------- 滚动渐显 ---------- */
.js .reveal{opacity:0;transform:translateY(30px);transition:opacity .8s cubic-bezier(.2,.7,.2,1),transform .8s cubic-bezier(.2,.7,.2,1)}
.js .reveal.in{opacity:1;transform:none}

/* ---------- 响应式 ---------- */
@media (max-width:960px){
  .ab-philo__grid{grid-template-columns:1fr 1fr}
  .ab-values__grid{grid-template-columns:1fr 1fr;gap:36px 30px}
  .ab-stats__grid{grid-template-columns:1fr 1fr}
  .ab-certs__grid{grid-template-columns:1fr 1fr}
  .ab-story__grid{grid-template-columns:1fr;gap:28px}
  .ab-story__aside{position:static}
}
@media (max-width:600px){
  .ab-hero{min-height:78vh;padding:120px 0 70px}
  .ab-philo__grid,.ab-values__grid,.ab-stats__grid,.ab-certs__grid{grid-template-columns:1fr}
  .ab-sec-head{text-align:left}
  .ab-sec-head .ab-eyebrow{justify-content:flex-start}
}