/* ============================================================
   上海联控达自动化技术有限公司
   设计系统 V2.0 — 专业企业官网
   ============================================================ */

/* --- 设计令牌 --- */
:root {
  --c-navy: #0a1628;
  --c-blue: #1a3a5c;
  --c-steel: #2c5f8a;
  --c-slate: #4a637a;
  --c-accent: #c8963e;
  --c-accent-dark: #a67c2e;
  --c-white: #ffffff;
  --c-warm: #f8f6f3;
  --c-gray-50: #f5f6f8;
  --c-gray-100: #eaecf0;
  --c-gray-200: #d5d9df;
  --c-gray-300: #b0b8c1;
  --c-gray-400: #8a94a1;
  --c-gray-500: #5f6b7a;
  --c-gray-600: #3e4854;
  --c-gray-700: #2a323d;
  --c-text: #1e2732;
  --c-text-soft: #556270;

  --ff: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', -apple-system, sans-serif;
  --ff-en: 'Inter', 'SF Pro Display', -apple-system, sans-serif;

  --w-max: 1200px;
  --h-nav: 68px;

  --radius-sm: 3px;
  --radius: 6px;

  --shadow-xs: 0 1px 2px rgba(10,22,40,.06);
  --shadow-sm: 0 2px 8px rgba(10,22,40,.07);
  --shadow-md: 0 6px 20px rgba(10,22,40,.10);
  --shadow-lg: 0 12px 40px rgba(10,22,40,.12);

  --ease: cubic-bezier(.4,0,.2,1);
  --ease-spring: cubic-bezier(.34,1.56,.64,1);
}

/* --- Reset --- */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;-webkit-font-smoothing:antialiased}
body{font-family:var(--ff);font-size:15px;color:var(--c-text);line-height:1.7;background:var(--c-white);min-width:320px;overflow-x:hidden}
a{color:inherit;text-decoration:none;transition:color .25s var(--ease)}
ul,ol{list-style:none}
img{max-width:100%;height:auto;display:block}
button{font-family:inherit;cursor:pointer}
input,select,textarea{font-family:inherit}

.container{width:100%;max-width:var(--w-max);margin:0 auto;padding:0 32px}

/* --- 排版 --- */
.section{padding:88px 0}
.section--sm{padding:60px 0}
.section--gray{background:var(--c-gray-50)}
.section--dark{background:var(--c-navy);color:rgba(255,255,255,.85)}

.section-label{
  display:inline-block;font-size:12px;font-weight:600;letter-spacing:.16em;
  color:var(--c-accent);text-transform:uppercase;margin-bottom:16px
}
.section-title{
  font-size:32px;font-weight:700;color:var(--c-navy);line-height:1.25;margin-bottom:16px;
  letter-spacing:-.01em
}
.section-title--light{color:var(--c-white)}
.section-desc{
  font-size:16px;color:var(--c-text-soft);line-height:1.7;max-width:580px
}
.section-desc--light{color:rgba(255,255,255,.7)}
.section-head{text-align:center;margin-bottom:56px}
.section-head .section-desc{margin:0 auto}

/* --- 按钮 --- */
.btn{
  display:inline-flex;align-items:center;gap:8px;padding:13px 32px;font-size:14px;
  font-weight:600;border-radius:var(--radius-sm);border:none;transition:all .25s var(--ease);
  letter-spacing:.02em;white-space:nowrap
}
.btn--primary{background:var(--c-blue);color:#fff}
.btn--primary:hover{background:var(--c-steel);transform:translateY(-1px);box-shadow:var(--shadow-md)}
.btn--accent{background:var(--c-accent);color:#fff}
.btn--accent:hover{background:var(--c-accent-dark);transform:translateY(-1px);box-shadow:var(--shadow-md)}
.btn--outline{background:transparent;color:var(--c-blue);border:1.5px solid var(--c-gray-200)}
.btn--outline:hover{border-color:var(--c-blue);background:rgba(26,58,92,.03)}
.btn--white{background:transparent;color:#fff;border:1.5px solid rgba(255,255,255,.35)}
.btn--white:hover{border-color:#fff;background:rgba(255,255,255,.08)}
.btn--sm{padding:9px 20px;font-size:13px}

/* --- 顶部导航 --- */
.navbar{
  position:fixed;top:0;left:0;right:0;z-index:1000;height:var(--h-nav);
  background:rgba(255,255,255,.97);backdrop-filter:blur(12px);
  border-bottom:1px solid transparent;transition:all .3s var(--ease)
}
.navbar--scrolled{border-bottom-color:var(--c-gray-100);box-shadow:var(--shadow-xs)}
.navbar__inner{display:flex;align-items:center;justify-content:space-between;height:100%}

.navbar__brand{display:flex;align-items:center;gap:12px;font-size:18px;font-weight:700;color:var(--c-navy);white-space:nowrap}
.navbar__brand-mark{
  width:38px;height:38px;background:var(--c-blue);border-radius:6px;
  display:flex;align-items:center;justify-content:center;
  color:#fff;font-size:15px;font-weight:700;flex-shrink:0;letter-spacing:-.02em
}

.navbar__links{display:flex;align-items:center;gap:2px}
.navbar__link{
  padding:8px 18px;font-size:13.5px;font-weight:500;
  color:var(--c-gray-600);border-radius:var(--radius-sm);
  transition:all .2s var(--ease);position:relative
}
.navbar__link:hover{color:var(--c-blue);background:rgba(26,58,92,.04)}
.navbar__link--active{color:var(--c-blue);font-weight:600}
.navbar__link--active::after{
  content:'';position:absolute;bottom:2px;left:50%;transform:translateX(-50%);
  width:18px;height:2px;background:var(--c-blue);border-radius:1px
}

.navbar__toggle{
  display:none;flex-direction:column;gap:5px;background:none;border:none;padding:8px
}
.navbar__toggle span{display:block;width:22px;height:1.5px;background:var(--c-gray-600);border-radius:1px;transition:all .25s var(--ease)}

/* --- 内页横幅 --- */
.page-hero{
  margin-top:var(--h-nav);height:300px;position:relative;overflow:hidden;
  background:var(--c-navy);display:flex;align-items:center;justify-content:center;text-align:center
}
.page-hero__bg{position:absolute;inset:0;object-fit:cover;opacity:.35}
.page-hero__body{position:relative;z-index:1;color:#fff}
.page-hero__title{font-size:34px;font-weight:700;letter-spacing:-.01em;margin-bottom:8px}
.page-hero__sub{font-size:15px;opacity:.75;font-weight:400}

/* --- 首页 Hero --- */
.hero{
  margin-top:var(--h-nav);position:relative;height:560px;overflow:hidden;background:var(--c-navy)
}
.hero__slide{position:absolute;inset:0;opacity:0;transition:opacity .8s var(--ease);display:flex;align-items:center}
.hero__slide--active{opacity:1}
.hero__slide img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;filter:brightness(.38)}
.hero__text{position:relative;z-index:1;color:#fff;max-width:620px}
.hero__text h2{font-size:40px;font-weight:700;line-height:1.2;margin-bottom:18px;letter-spacing:-.02em}
.hero__text p{font-size:17px;opacity:.85;line-height:1.7;margin-bottom:32px}
.hero__controls{position:absolute;bottom:32px;left:50%;transform:translateX(-50%);display:flex;gap:8px;z-index:2}
.hero__dot{width:8px;height:8px;border-radius:50%;background:rgba(255,255,255,.4);border:none;cursor:pointer;transition:all .3s var(--ease)}
.hero__dot--active{background:var(--c-accent);width:24px;border-radius:4px}
.hero__arrow{
  position:absolute;top:50%;transform:translateY(-50%);z-index:2;
  width:46px;height:46px;border-radius:50%;background:rgba(255,255,255,.1);
  border:1px solid rgba(255,255,255,.2);color:#fff;font-size:18px;
  display:flex;align-items:center;justify-content:center;
  transition:all .25s var(--ease);backdrop-filter:blur(8px)
}
.hero__arrow:hover{background:rgba(255,255,255,.2)}
.hero__arrow--prev{left:28px}.hero__arrow--next{right:28px}

/* --- 信息行（图文混排）--- */
.split{display:grid;grid-template-columns:1fr 1fr;gap:64px;align-items:center}
.split__img{border-radius:var(--radius);overflow:hidden;aspect-ratio:4/3}
.split__img img{width:100%;height:100%;object-fit:cover}
.split__text h3{font-size:26px;font-weight:700;color:var(--c-navy);margin-bottom:18px;letter-spacing:-.01em}
.split__text p{font-size:15px;color:var(--c-text-soft);line-height:1.85;margin-bottom:14px}
.split__text p:last-child{margin-bottom:0}

/* --- 服务网格 --- */
.service-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--c-gray-100);border-radius:var(--radius);overflow:hidden}
.service-item{background:var(--c-white);padding:40px 32px;transition:all .25s var(--ease);position:relative}
.service-item:hover{background:var(--c-gray-50)}
.service-item__icon{width:44px;height:44px;margin-bottom:20px;color:var(--c-blue);font-size:28px;display:flex;align-items:center}
.service-item h4{font-size:17px;font-weight:600;margin-bottom:10px;color:var(--c-navy)}
.service-item p{font-size:14px;color:var(--c-text-soft);line-height:1.75}

/* --- 产品卡片 --- */
.product-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
@media (max-width:900px){.product-grid{grid-template-columns:repeat(2,1fr)}}
@media (max-width:560px){.product-grid{grid-template-columns:1fr}}

.product-card{border:1px solid var(--c-gray-100);border-radius:var(--radius);overflow:hidden;transition:all .3s var(--ease);background:#fff}
.product-card:hover{border-color:var(--c-gray-200);box-shadow:var(--shadow-md);transform:translateY(-2px)}
.product-card__img{height:200px;overflow:hidden;background:var(--c-gray-50)}
.product-card__img img{width:100%;height:100%;object-fit:cover;transition:transform .5s var(--ease)}
.product-card:hover .product-card__img img{transform:scale(1.04)}
.product-card__body{padding:22px}
.product-card .tag{display:inline-block;font-size:11px;font-weight:600;letter-spacing:.08em;color:var(--c-accent);text-transform:uppercase;margin-bottom:8px}
.product-card h4{font-size:17px;font-weight:600;color:var(--c-navy);margin-bottom:8px}
.product-card p{font-size:13.5px;color:var(--c-text-soft);line-height:1.7}

/* --- 案例条目 --- */
.case-row{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
@media (max-width:700px){.case-row{grid-template-columns:1fr}}

.case-item{display:flex;gap:18px;padding:22px;border:1px solid var(--c-gray-100);border-radius:var(--radius);transition:all .25s var(--ease)}
.case-item:hover{border-color:var(--c-gray-200);box-shadow:var(--shadow-sm)}
.case-item__thumb{width:120px;height:90px;border-radius:var(--radius-sm);overflow:hidden;flex-shrink:0;background:var(--c-gray-50)}
.case-item__thumb img{width:100%;height:100%;object-fit:cover}
.case-item__info{flex:1;min-width:0}
.case-item__info h4{font-size:15px;font-weight:600;color:var(--c-navy);margin-bottom:4px}
.case-item__info .meta{font-size:12px;color:var(--c-gray-400);margin-bottom:4px}
.case-item__info .desc{font-size:13px;color:var(--c-text-soft);line-height:1.6}
@media (max-width:560px){.case-item{flex-direction:column}.case-item__thumb{width:100%;height:140px}}

/* --- 数据条 --- */
.stat-bar{display:grid;grid-template-columns:repeat(4,1fr);text-align:center;gap:0;position:relative}
.stat-bar::after{content:'';position:absolute;left:25%;top:10%;bottom:10%;width:1px;background:var(--c-gray-100)}
.stat-bar::before{content:'';position:absolute;left:50%;top:10%;bottom:10%;width:1px;background:var(--c-gray-100)}
.stat-bar__line2{position:absolute;left:75%;top:10%;bottom:10%;width:1px;background:var(--c-gray-100)}
.stat-bar__num{font-size:40px;font-weight:700;color:var(--c-blue);letter-spacing:-.02em}
.stat-bar__label{font-size:13px;color:var(--c-text-soft);margin-top:4px}
@media (max-width:600px){.stat-bar{grid-template-columns:repeat(2,1fr);gap:24px}
  .stat-bar::after,.stat-bar::before,.stat-bar__line2{display:none}}

/* --- Tab 切换 --- */
.tabs{display:flex;justify-content:center;gap:0;border-bottom:1.5px solid var(--c-gray-100);margin-bottom:44px}
.tab-btn{padding:14px 36px;background:none;border:none;font-size:15px;font-weight:500;color:var(--c-gray-500);position:relative;transition:color .2s var(--ease)}
.tab-btn:hover{color:var(--c-blue)}
.tab-btn--active{color:var(--c-navy);font-weight:600}
.tab-btn--active::after{content:'';position:absolute;bottom:-1.5px;left:0;right:0;height:2.5px;background:var(--c-blue);border-radius:2px 2px 0 0}
.tab-panel{display:none;animation:fadeUp .4s var(--ease)}
.tab-panel--active{display:block}
@keyframes fadeUp{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}

/* --- 品牌条 --- */
.brand-strip{display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:44px;padding:20px 0}
.brand-strip img{height:38px;opacity:.45;filter:grayscale(100%);transition:all .3s var(--ease)}
.brand-strip img:hover{opacity:.8;filter:grayscale(0%)}
.brand-pill{
  display:inline-flex;align-items:center;justify-content:center;min-width:136px;height:46px;
  padding:0 20px;border:1px solid var(--c-gray-100);border-radius:999px;background:#fff;
  color:var(--c-gray-600);font-size:13px;font-weight:600;letter-spacing:.04em;
  box-shadow:var(--shadow-xs);transition:all .25s var(--ease)
}
.brand-pill:hover{color:var(--c-blue);border-color:var(--c-gray-200);box-shadow:var(--shadow-sm);transform:translateY(-1px)}

/* --- 流程步骤 --- */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:0;position:relative}
.steps::after{content:'';position:absolute;top:36px;left:12.5%;right:12.5%;height:1px;background:var(--c-gray-100);z-index:0}
.step{text-align:center;position:relative;z-index:1;padding:0 16px}
.step__num{width:72px;height:72px;border-radius:50%;background:var(--c-gray-50);border:2px solid var(--c-gray-100);display:flex;align-items:center;justify-content:center;margin:0 auto 16px;font-size:22px;font-weight:700;color:var(--c-gray-400);transition:all .3s var(--ease)}
.step:hover .step__num{background:var(--c-blue);border-color:var(--c-blue);color:#fff}
.step h5{font-size:15px;font-weight:600;color:var(--c-navy);margin-bottom:6px}
.step p{font-size:13px;color:var(--c-text-soft);line-height:1.6}
@media (max-width:700px){.steps{grid-template-columns:repeat(2,1fr);gap:28px}.steps::after{display:none}}

/* --- 联系我们 --- */
.contact-layout{display:grid;grid-template-columns:1fr 1.3fr;gap:56px}
.contact-info h3{font-size:26px;font-weight:700;color:var(--c-navy);margin-bottom:24px;letter-spacing:-.01em}
.contact-info__row{display:flex;gap:14px;margin-bottom:22px}
.contact-info__icon{width:44px;height:44px;border-radius:50%;background:var(--c-gray-50);display:flex;align-items:center;justify-content:center;color:var(--c-blue);font-size:18px;flex-shrink:0}
.contact-info__label{font-size:12px;color:var(--c-gray-400);margin-bottom:2px;text-transform:uppercase;letter-spacing:.06em}
.contact-info__val{font-size:15px;font-weight:600;color:var(--c-navy)}

.form-card{background:var(--c-gray-50);padding:40px;border-radius:var(--radius)}
.form-card h3{font-size:22px;font-weight:700;color:var(--c-navy);margin-bottom:26px}
.form-row{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:16px}
.form-group{margin-bottom:16px}
.form-group label{display:block;font-size:13px;font-weight:500;color:var(--c-gray-700);margin-bottom:6px}
.form-group label .req{color:#c0392b}
.form-input,.form-textarea{width:100%;padding:12px 14px;border:1.5px solid var(--c-gray-200);border-radius:var(--radius-sm);font-size:14px;background:#fff;color:var(--c-text);transition:border-color .2s}
.form-input:focus,.form-textarea:focus{outline:none;border-color:var(--c-blue)}
.form-textarea{resize:vertical;min-height:130px}
.form-input::placeholder,.form-textarea::placeholder{color:var(--c-gray-300)}

/* --- 资质卡片 --- */
.cert-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
@media (max-width:900px){.cert-grid{grid-template-columns:repeat(2,1fr)}}
.cert-card{cursor:pointer;border:1px solid var(--c-gray-100);border-radius:var(--radius);overflow:hidden;transition:all .25s var(--ease)}
.cert-card:hover{border-color:var(--c-gray-200);box-shadow:var(--shadow-sm)}
.cert-card__img{width:100%;aspect-ratio:3/4;background:var(--c-gray-50);display:flex;align-items:center;justify-content:center;color:var(--c-gray-300);font-size:13px;text-align:center;padding:16px}
.cert-card__label{padding:12px;text-align:center;font-size:13px;font-weight:500;color:var(--c-gray-500)}
.cert-card img{width:100%;height:100%;object-fit:contain}
.cert-card .placeholder-text{font-size:13px;color:var(--c-gray-300);text-align:center}

/* --- 模态弹窗 --- */
.modal-overlay{position:fixed;inset:0;z-index:9999;background:rgba(10,22,40,.8);display:flex;align-items:center;justify-content:center;opacity:0;visibility:hidden;transition:all .3s var(--ease);backdrop-filter:blur(4px)}
.modal-overlay--open{opacity:1;visibility:visible}
.modal-body{max-width:90vw;max-height:90vh;position:relative}
.modal-body img{max-height:85vh;border-radius:4px}
.modal-close{position:absolute;top:-40px;right:0;background:none;border:none;color:#fff;font-size:28px;cursor:pointer;transition:opacity .2s}
.modal-close:hover{opacity:.7}

/* --- 页脚 --- */
.footer{background:var(--c-navy);color:rgba(255,255,255,.6);padding:64px 0 24px}
.footer__grid{display:grid;grid-template-columns:2.5fr 1fr 1fr 1.3fr;gap:40px;margin-bottom:40px}
@media (max-width:900px){.footer__grid{grid-template-columns:1fr 1fr}}
@media (max-width:540px){.footer__grid{grid-template-columns:1fr}}
.footer h5{color:#fff;font-size:15px;font-weight:600;margin-bottom:16px}
.footer p,.footer a,.footer span{font-size:13.5px;line-height:2.1;display:block}
.footer a:hover{color:var(--c-accent)}
.footer__bottom{border-top:1px solid rgba(255,255,255,.08);padding-top:20px;text-align:center;font-size:12.5px}
.footer__bottom a{display:inline;color:inherit;font-size:inherit;line-height:inherit}
.footer__brand{font-size:17px;font-weight:700;color:#fff;margin-bottom:12px}

/* --- 面包屑 --- */
.breadcrumb{padding:14px 0;font-size:13px;color:var(--c-gray-400)}
.breadcrumb a{color:var(--c-gray-500)}.breadcrumb a:hover{color:var(--c-blue)}
.breadcrumb span{margin:0 6px;color:var(--c-gray-300)}

/* --- 返回顶部 --- */
#backToTop{position:fixed;bottom:28px;right:28px;z-index:998;width:42px;height:42px;border-radius:50%;background:var(--c-blue);color:#fff;border:none;font-size:16px;cursor:pointer;box-shadow:var(--shadow-sm);opacity:0;visibility:hidden;transition:all .3s var(--ease);display:flex;align-items:center;justify-content:center}
#backToTop--visible{opacity:1;visibility:visible}
#backToTop:hover{background:var(--c-steel);transform:translateY(-2px);box-shadow:var(--shadow-md)}

/* --- 占位图片 --- */
.img-placeholder{background:var(--c-gray-50);display:flex;align-items:center;justify-content:center;color:var(--c-gray-300);font-size:13px;text-align:center;overflow:hidden}

/* --- 突出卡片 --- */
.feature-card{background:var(--c-gray-50);border-radius:var(--radius);padding:36px 32px;text-align:center;transition:all .25s var(--ease)}
.feature-card:hover{background:var(--c-white);box-shadow:var(--shadow-md);transform:translateY(-2px)}
.feature-card__icon{font-size:32px;color:var(--c-blue);margin-bottom:18px}
.feature-card h4{font-size:16px;font-weight:600;color:var(--c-navy);margin-bottom:8px}
.feature-card p{font-size:13.5px;color:var(--c-text-soft);line-height:1.7}

/* --- 高亮数字区块 --- */
.highlight-box{border-left:3px solid var(--c-accent);padding:14px 20px;margin-top:20px;background:rgba(200,150,62,.04)}
.highlight-box p{font-size:14px;color:var(--c-gray-600);line-height:1.8;margin:0}

/* --- 响应式 --- */
@media (max-width:1024px){
  .split{grid-template-columns:1fr;gap:32px}
  .service-grid{grid-template-columns:repeat(2,1fr)}
  .contact-layout{grid-template-columns:1fr}
}

@media (max-width:768px){
  :root{--h-nav:60px}
  .container{padding:0 20px}
  .section{padding:60px 0}
  .section-title{font-size:26px}
  .hero{height:380px}
  .hero__text h2{font-size:28px}
  .hero__text p{font-size:15px}
  .hero__arrow{display:none}
  .page-hero{height:200px}
  .page-hero__title{font-size:26px}
  .navbar__links{
    position:fixed;top:var(--h-nav);left:0;right:0;background:#fff;
    flex-direction:column;padding:12px 0;border-bottom:1px solid var(--c-gray-100);
    box-shadow:var(--shadow-sm);transform:translateY(-8px);opacity:0;
    visibility:hidden;transition:all .25s var(--ease)
  }
  .navbar__links--open{transform:translateY(0);opacity:1;visibility:visible}
  .navbar__toggle{display:flex}
  .service-grid{grid-template-columns:1fr}
  .product-grid{grid-template-columns:repeat(2,1fr)}
  .form-row{grid-template-columns:1fr}
  .cert-grid{grid-template-columns:repeat(2,1fr)}
  .stat-bar{grid-template-columns:repeat(2,1fr);gap:20px}
  .steps{grid-template-columns:repeat(2,1fr);gap:24px}.steps::after{display:none}
}

@media (max-width:480px){
  .product-grid{grid-template-columns:1fr}
  .tabs{flex-wrap:wrap}.tab-btn{padding:10px 18px;font-size:13px}
  .case-row{grid-template-columns:1fr}
  .split__img{aspect-ratio:3/2}
}