/* ===== Reset & Base ===== */
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:70px}
body{
  font-family:"Microsoft YaHei","PingFang SC","Helvetica Neue",sans-serif;
  font-size:15px;line-height:1.8;color:#444;background:#fff;
  -webkit-font-smoothing:antialiased;
}
a{text-decoration:none;color:inherit}
img{max-width:100%;display:block}
.container{max-width:1200px;margin:0 auto;padding:0 24px}

:root{
  --blue:#0d2b4a;
  --gold:#b8860b;
  --gold2:#d4a017;
  --gray1:#f6f6f6;
  --gray2:#e5e5e5;
  --gray3:#999;
  --white:#fff;
  --shadow:0 2px 12px rgba(0,0,0,.06);
  --shadow2:0 8px 24px rgba(0,0,0,.1);
  --radius:6px;
}

/* ===== Header ===== */
.header{
  position:fixed;top:0;left:0;right:0;z-index:1000;
  background:rgba(13,43,74,.96);backdrop-filter:blur(6px);
  border-bottom:1px solid rgba(255,255,255,.08);
}
.nav-bar{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo-link{display:flex;align-items:center;gap:10px}
.logo-img{height:44px;width:auto;object-fit:contain}
.logo-title{font-size:18px;font-weight:700;color:var(--white);letter-spacing:2px}
.logo-sub{font-size:10px;color:rgba(255,255,255,.5);letter-spacing:1px;display:block}

.nav{display:flex;gap:2px}
.nav-link{
  color:rgba(255,255,255,.78);padding:8px 14px;font-size:13px;border-radius:3px;
  transition:.2s;white-space:nowrap;
}
.nav-link:hover,.nav-link.active{color:var(--white);background:rgba(255,255,255,.08)}
.nav-link.active{color:var(--gold2)}

.nav-toggle{display:none;background:none;border:none;color:var(--white);font-size:24px;cursor:pointer}

/* ===== Banner ===== */
.banner{
  margin-top:68px;position:relative;min-height:520px;
  display:flex;align-items:center;justify-content:center;
  background:url(../images/hero_bg.jpg) center/cover no-repeat;
}
.banner::before{
  content:'';position:absolute;inset:0;
  background:linear-gradient(135deg,rgba(13,43,74,.88) 0%,rgba(13,43,74,.72) 100%);
}
.banner-content{position:relative;z-index:1;max-width:800px;padding:80px 24px;text-align:center}
.banner-content h1{font-size:42px;font-weight:700;color:var(--white);letter-spacing:5px;margin-bottom:10px}
.banner-en{font-size:12px;color:rgba(255,255,255,.45);letter-spacing:3px;margin-bottom:24px}
.banner-divider{width:50px;height:2px;background:var(--gold2);margin:0 auto 24px}
.banner-slogan{font-size:16px;color:rgba(255,255,255,.7);letter-spacing:3px;margin-bottom:40px}
.banner-btns{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}

.btn{display:inline-block;padding:13px 36px;font-size:14px;font-weight:600;border-radius:3px;letter-spacing:1px;transition:.3s;cursor:pointer;border:1px solid transparent}
.btn-primary{background:var(--gold2);color:var(--white);border-color:var(--gold2)}
.btn-primary:hover{background:transparent;color:var(--gold2)}
.btn-outline{background:transparent;color:var(--white);border-color:rgba(255,255,255,.3)}
.btn-outline:hover{border-color:var(--white);background:rgba(255,255,255,.06)}

/* ===== Quick Nav ===== */
.quick-nav{background:var(--white);border-bottom:1px solid var(--gray2)}
.quick-grid{display:grid;grid-template-columns:repeat(4,1fr)}
.quick-item{
  display:flex;align-items:center;gap:18px;padding:28px 30px;
  transition:.3s;position:relative;
}
.quick-item::after{content:'';position:absolute;right:0;top:15%;height:70%;width:1px;background:var(--gray2)}
.quick-item:last-child::after{display:none}
.quick-item:hover{background:var(--gray1)}
.quick-num{font-size:28px;font-weight:800;color:var(--gray2);min-width:40px;transition:.3s}
.quick-title{font-size:15px;font-weight:700;color:var(--blue);display:block}
.quick-desc{font-size:12px;color:var(--gray3);display:block;margin-top:2px}
.quick-item:hover .quick-num{color:var(--gold2)}
.quick-item:hover .quick-title{color:var(--gold2)}

/* ===== Section Common ===== */
.section{padding:80px 0}
.bg-gray{background:var(--gray1)}
.section-head{text-align:center;margin-bottom:50px}
.section-tag{font-size:11px;color:var(--gold2);letter-spacing:3px;font-weight:600;text-transform:uppercase}
.section-head h2{font-size:30px;font-weight:700;color:var(--blue);margin:10px 0;letter-spacing:2px}
.section-head p{font-size:14px;color:var(--gray3);max-width:500px;margin:0 auto}

/* ===== About ===== */
.about-layout{max-width:860px;margin:0 auto}
.about-content p{text-indent:2em;margin-bottom:14px;color:#555;font-size:14px;line-height:2}
.about-numbers{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:40px}
.number-card{
  text-align:center;padding:28px 16px;background:var(--white);
  border:1px solid var(--gray2);border-radius:var(--radius);transition:.3s;
}
.number-card:hover{border-color:var(--gold2);box-shadow:var(--shadow);transform:translateY(-2px)}
.number-val{display:block;font-size:34px;font-weight:700;color:var(--blue)}
.number-lbl{font-size:13px;color:var(--gray3);margin-top:4px}

/* ===== Qualifications ===== */
.qual-list{max-width:720px;margin:0 auto}
.qual-row{
  display:flex;align-items:center;gap:20px;
  padding:18px 24px;background:var(--white);margin-bottom:10px;
  border-left:3px solid transparent;border-radius:var(--radius);
  box-shadow:var(--shadow);transition:.3s;
}
.qual-row:hover{border-left-color:var(--gold2);transform:translateX(4px)}
.qual-badge{
  display:inline-block;padding:5px 16px;background:var(--blue);color:var(--white);
  font-size:12px;font-weight:700;border-radius:2px;flex-shrink:0;min-width:50px;text-align:center;
}
.qual-row span:last-child{font-size:14px;color:#333;font-weight:500}

/* ===== Business Tags ===== */
.biz-tags{display:flex;flex-wrap:wrap;gap:12px;justify-content:center;max-width:820px;margin:0 auto}
.biz-tags span{
  padding:10px 22px;background:var(--white);border:1px solid var(--gray2);
  border-radius:2px;font-size:14px;color:#555;transition:.3s;
}
.biz-tags span:hover{border-color:var(--blue);color:var(--white);background:var(--blue)}

/* ===== Cases ===== */
.cases-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.case-card{
  background:var(--white);border-radius:var(--radius);overflow:hidden;
  box-shadow:var(--shadow);transition:.3s;
}
.case-card:hover{transform:translateY(-5px);box-shadow:var(--shadow2)}
.case-img-wrap{overflow:hidden;height:240px}
.case-img-wrap img{width:100%;height:100%;object-fit:cover;object-position:center;transition:.5s}
.case-card:hover .case-img-wrap img{transform:scale(1.06)}
.case-label{display:block;text-align:center;padding:16px;font-size:14px;font-weight:600;color:var(--blue);letter-spacing:1px}

/* ===== Milestone Timeline ===== */
.milestone-track{
  position:relative;max-width:900px;margin:0 auto;padding:10px 0;
}
.milestone-track::before{
  content:'';position:absolute;left:50%;top:0;bottom:0;width:2px;
  background:var(--gray2);transform:translateX(-50%);
}

/* Year marker */
.ms-year-marker{
  text-align:center;margin:30px 0 40px;position:relative;z-index:2;
}
.ms-year-marker:first-child{margin-top:0}
.ms-year-marker span{
  display:inline-block;background:var(--blue);color:var(--white);
  font-size:22px;font-weight:800;padding:8px 28px;border-radius:4px;
  letter-spacing:4px;
}

/* Timeline item */
.ms-item{
  position:relative;width:50%;margin-bottom:36px;cursor:pointer;
}
.ms-item.left{left:0;padding-right:60px;text-align:right}
.ms-item.right{left:50%;padding-left:60px;text-align:left}

/* Dot */
.ms-dot{
  position:absolute;top:20px;width:14px;height:14px;
  background:var(--gold2);border:3px solid var(--white);
  border-radius:50%;z-index:2;
  box-shadow:0 0 0 3px var(--gold2);
}
.ms-item.left .ms-dot{right:-10px}
.ms-item.right .ms-dot{left:-10px}

/* Card */
.ms-card{
  background:var(--white);padding:20px 24px;border-radius:var(--radius);
  box-shadow:var(--shadow);transition:.3s;
  border-bottom:3px solid transparent;display:inline-block;
}
.ms-item.left .ms-card{border-bottom-color:var(--gray2)}
.ms-item.right .ms-card{border-bottom-color:var(--gray2)}
.ms-item:hover .ms-card{
  transform:translateY(-3px);box-shadow:var(--shadow2);
  border-bottom-color:var(--gold2);
}
.ms-date{
  font-size:12px;color:var(--gold2);font-weight:700;letter-spacing:1px;
  display:block;margin-bottom:6px;
}
.ms-card h4{font-size:15px;color:var(--blue);margin-bottom:6px;line-height:1.4}
.ms-card p{font-size:12px;color:var(--gray3);line-height:1.7;margin:0}

/* ===== Modal ===== */
.modal-overlay{
  position:fixed;inset:0;z-index:2000;background:rgba(0,0,0,.55);
  display:flex;align-items:center;justify-content:center;opacity:0;pointer-events:none;
  transition:opacity .3s;
}
.modal-overlay.open{opacity:1;pointer-events:auto}
.modal-box{
  background:var(--white);border-radius:8px;max-width:700px;width:92%;
  max-height:85vh;overflow-y:auto;position:relative;box-shadow:0 20px 60px rgba(0,0,0,.25);
  transform:translateY(20px);transition:transform .3s;
}
.modal-overlay.open .modal-box{transform:translateY(0)}
.modal-close{
  position:absolute;top:12px;right:16px;background:none;border:none;
  font-size:28px;color:var(--gray3);cursor:pointer;z-index:3;line-height:1;transition:.2s;
}
.modal-close:hover{color:var(--blue)}
.modal-body{padding:40px 36px}
.modal-body h2{font-size:24px;color:var(--blue);margin-bottom:6px}
.modal-body .modal-date{font-size:13px;color:var(--gray3);margin-bottom:24px;display:block}
.modal-body .modal-text{font-size:14px;color:#555;line-height:2;margin-bottom:24px}
.modal-body .modal-text p{margin-bottom:14px;text-indent:2em}
.modal-body .modal-img{border-radius:var(--radius);margin-bottom:20px;box-shadow:var(--shadow);width:100%}
.modal-body .modal-gallery{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-bottom:20px}
.modal-body .modal-gallery img{border-radius:var(--radius);width:100%;aspect-ratio:4/3;object-fit:cover}
.modal-body .modal-highlight{background:var(--gray1);padding:20px 24px;border-radius:var(--radius);margin-bottom:20px}
.modal-body .modal-highlight h4{font-size:14px;color:var(--blue);margin-bottom:8px}
.modal-body .modal-highlight ul{padding-left:20px}
.modal-body .modal-highlight li{font-size:13px;color:var(--gray4);line-height:2}

/* ===== Team Departments ===== */
.dept-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px;max-width:920px;margin:0 auto}
.dept-card{
  text-align:center;padding:40px 24px;background:var(--white);
  border:1px solid var(--gray2);border-radius:var(--radius);transition:.3s;
}
.dept-card:hover{border-color:var(--gold2);box-shadow:var(--shadow2);transform:translateY(-3px)}
.dept-icon{font-size:40px;margin-bottom:16px}
.dept-card h4{font-size:16px;color:var(--blue);margin-bottom:10px}
.dept-card p{font-size:12px;color:var(--gray3);line-height:1.7}

/* ===== Contact ===== */
.contact-cards{display:grid;grid-template-columns:repeat(2,1fr);gap:20px;max-width:720px;margin:0 auto}
.contact-card{
  display:flex;align-items:flex-start;gap:16px;
  padding:24px;background:var(--white);border:1px solid var(--gray2);
  border-radius:var(--radius);transition:.3s;
}
.contact-card:hover{border-color:var(--gold2);box-shadow:var(--shadow)}
.contact-ico{
  font-size:26px;width:52px;height:52px;display:flex;align-items:center;
  justify-content:center;background:var(--blue);color:var(--white);
  border-radius:50%;flex-shrink:0;
}
.contact-card h4{font-size:13px;color:var(--gray3);margin-bottom:4px}
.contact-val{font-size:16px;font-weight:600;color:var(--blue)}

/* ===== Footer ===== */
.footer{background:var(--blue);color:rgba(255,255,255,.6);padding:50px 0 0}
.footer-main{display:flex;justify-content:space-between;gap:40px;flex-wrap:wrap;margin-bottom:40px}
.footer-info h3{font-size:18px;color:var(--white);letter-spacing:2px;margin-bottom:8px}
.footer-info p{font-size:12px;line-height:2}
.footer-slogan{color:rgba(255,255,255,.35);margin-top:10px}
.footer-links h4{font-size:14px;color:var(--white);margin-bottom:14px}
.footer-links a{display:block;font-size:12px;padding:4px 0;transition:.2s}
.footer-links a:hover{color:var(--gold2)}
.footer-copy{border-top:1px solid rgba(255,255,255,.06);padding:18px 0;text-align:center;font-size:12px;color:rgba(255,255,255,.3)}

/* ===== Back to Top ===== */
.back-top{
  position:fixed;bottom:30px;right:30px;width:44px;height:44px;
  background:var(--blue);color:var(--white);border:1px solid rgba(255,255,255,.1);
  border-radius:50%;font-size:22px;cursor:pointer;display:none;z-index:999;
  transition:.3s;text-align:center;line-height:42px;
}
.back-top:hover{background:var(--gold2);border-color:var(--gold2)}

/* ===== Responsive ===== */
@media(max-width:900px){
  .nav{display:none}
  .nav.open{
    display:flex;flex-direction:column;position:absolute;top:68px;left:0;right:0;
    background:rgba(13,43,74,.98);padding:8px 0;box-shadow:0 4px 12px rgba(0,0,0,.2);
  }
  .nav.open .nav-link{padding:14px 24px;border-bottom:1px solid rgba(255,255,255,.06);border-radius:0}
  .nav-toggle{display:block}
  .banner{min-height:400px}
  .banner-content h1{font-size:28px;letter-spacing:2px}
  .banner-slogan{font-size:13px;letter-spacing:1px}
  .quick-grid{grid-template-columns:repeat(2,1fr)}
  .about-numbers{grid-template-columns:repeat(2,1fr)}
  .cases-grid{grid-template-columns:repeat(2,1fr)}
  .dept-grid{grid-template-columns:repeat(2,1fr)}
  .contact-cards{grid-template-columns:1fr}
  .milestone-track::before{left:20px;transform:none}
  .ms-item{width:100%;left:0!important;padding-left:50px!important;padding-right:0!important;text-align:left!important}
  .ms-year-marker{text-align:left;padding-left:12px;margin:24px 0 28px}
  .ms-dot{left:14px!important;right:auto!important}
  .ms-card{display:block}
  .section{padding:60px 0}
  .section-head h2{font-size:24px}
  .modal-body{padding:28px 20px}
  .modal-body .modal-gallery{grid-template-columns:1fr}
}

@media(max-width:500px){
  .banner{min-height:340px}
  .banner-content h1{font-size:22px}
  .cases-grid,.dept-grid,.contact-cards{grid-template-columns:1fr}
  .footer-main{flex-direction:column;gap:30px}
}