/* =========================================================
   北京芊语科技有限公司 官网样式
   浅色清爽版 · 参考硅谷SaaS简约风 · 响应式
   ========================================================= */

:root{
  --deep:#0d1530;
  --navy:#12204a;
  --blue:#2f6bff;
  --blue2:#00a8ff;
  --grad:linear-gradient(135deg,#2f6bff 0%,#00a8ff 55%,#00d0ff 100%);
  --text:#1f2a45;
  --muted:#5c6b84;
  --bg:#f7f9fd;
  --card:#ffffff;
  --border:rgba(47,107,255,.12);
}

*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
  color:var(--text);
  line-height:1.7;
  background:
    radial-gradient(900px 400px at 10% 0%,rgba(47,107,255,.06) 0%,transparent 60%),
    radial-gradient(1000px 500px at 90% 20%,rgba(0,208,255,.05) 0%,transparent 60%),
    linear-gradient(180deg,#f7f9fd 0%,#ffffff 30%);
  background-attachment:fixed;
  overflow-x:hidden;
}
a{text-decoration:none;color:inherit;}
img{max-width:100%;display:block;}
.container{width:min(1180px,92%);margin:0 auto;}
section{position:relative;}

/* ---------- 导航 ---------- */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:1000;
  background:linear-gradient(180deg,rgba(255,255,255,.95),rgba(255,255,255,.82));
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid rgba(47,107,255,.12);
  box-shadow:0 1px 0 rgba(47,107,255,.04);
  transition:.3s;
}
.navbar{display:flex;align-items:center;justify-content:space-between;height:70px;}
.brand{display:flex;align-items:center;gap:10px;}
.brand-logo{height:64px;width:auto;}
.nav-menu{display:flex;list-style:none;gap:34px;}
.nav-menu a{color:#3d4a6b;font-size:1.08rem;transition:.2s;position:relative;font-weight:500;}
.nav-menu a::after{content:"";position:absolute;left:0;bottom:-6px;width:0;height:2px;background:var(--grad);transition:.3s;border-radius:2px;}
.nav-menu a:hover,.nav-menu a.active{color:#2f6bff;}
.nav-menu a.active::after{width:100%;}
.nav-cta{
  padding:9px 22px;border-radius:30px;color:#fff;font-size:1rem;font-weight:600;
  background:var(--grad);box-shadow:0 6px 20px rgba(47,107,255,.28);transition:.3s;
}
.nav-cta:hover{transform:translateY(-2px);box-shadow:0 10px 26px rgba(47,107,255,.4);}

/* 移动端导航 */
.nav-toggle{display:none;flex-direction:column;gap:5px;background:none;border:none;cursor:pointer;padding:6px;}
.nav-toggle span{width:26px;height:2.5px;background:#12204a;border-radius:2px;transition:.3s;}
.nav-toggle.open span:nth-child(1){transform:translateY(7.5px) rotate(45deg);}
.nav-toggle.open span:nth-child(2){opacity:0;}
.nav-toggle.open span:nth-child(3){transform:translateY(-7.5px) rotate(-45deg);}

/* ---------- Hero ---------- */
.hero{
  min-height:100vh;display:flex;align-items:center;
  color:var(--text);padding:140px 0 60px;
  background:
    radial-gradient(1100px 620px at 88% -10%,rgba(47,107,255,.14) 0%,transparent 55%),
    radial-gradient(1000px 560px at -5% 115%,rgba(0,208,255,.12) 0%,transparent 55%),
    radial-gradient(700px 400px at 60% 60%,rgba(100,120,255,.05) 0%,transparent 60%),
    linear-gradient(180deg,#ffffff 0%,#e8effc 100%);
  overflow:hidden;
}
.hero-bg{position:absolute;inset:0;opacity:1;pointer-events:none;
  background:
    linear-gradient(rgba(47,107,255,.045) 1px,transparent 1px),
    linear-gradient(90deg,rgba(47,107,255,.045) 1px,transparent 1px);
  background-size:56px 56px;
  -webkit-mask-image:radial-gradient(ellipse 90% 70% at 60% 40%,#000 0%,transparent 100%);
  mask-image:radial-gradient(ellipse 90% 70% at 60% 40%,#000 0%,transparent 100%);
}
.hero-content{position:relative;z-index:2;animation:fadeUp .8s ease;max-width:760px;text-align:left;}
.hero-eyebrow{
  display:inline-block;padding:7px 18px;border-radius:30px;margin-bottom:22px;
  font-size:1.1rem;letter-spacing:2px;color:#2f6bff;
  border:1px solid rgba(47,107,255,.25);background:rgba(47,107,255,.06);
}
.hero-title{font-size:clamp(2.2rem,5vw,3.8rem);font-weight:800;line-height:1.25;letter-spacing:1px;color:#0d1530;}
.hero-title span{background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;padding:0 6px;}
.hero-sub{max-width:640px;margin:24px 0 34px;color:var(--muted);font-size:1.18rem;}
.hero-actions{display:flex;gap:16px;flex-wrap:wrap;}
.btn{padding:13px 32px;border-radius:30px;font-size:1rem;font-weight:600;transition:.3s;display:inline-block;}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 8px 24px rgba(47,107,255,.35);}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 12px 30px rgba(47,107,255,.5);}
.btn-ghost{border:1.5px solid rgba(47,107,255,.4);color:#2f6bff;background:#fff;}
.btn-ghost:hover{background:rgba(47,107,255,.06);}
.hero-stats{display:flex;gap:54px;margin-top:60px;flex-wrap:wrap;}
.stat{display:flex;flex-direction:column;}
.stat .num{font-size:2.4rem;font-weight:800;background:linear-gradient(135deg,#2f6bff 0%,#00a8ff 70%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;}
.stat .label{color:var(--muted);font-size:1.05rem;letter-spacing:1px;}

/* ---------- 通用 section ---------- */
.section{padding:100px 0;}
.alt{background:linear-gradient(180deg,#f4f8ff 0%,#eef3fc 100%);}
.section-head{text-align:center;margin-bottom:56px;position:relative;}
.section-eyebrow{color:#2f6bff;font-weight:800;letter-spacing:1px;font-size:clamp(1.8rem,3.2vw,2.6rem);margin-bottom:10px;line-height:1.3;}
.section-eyebrow::after{content:"";display:block;width:52px;height:4px;border-radius:4px;margin:14px auto 0;background:var(--grad);}
.section-title{font-size:2rem;font-weight:600;color:#333;line-height:1.6;letter-spacing:.5px;}
.section-desc{color:var(--muted);margin-top:14px;font-size:1.12rem;}

/* ---------- 关于 ---------- */
.about-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:48px;align-items:center;}
.about-text p{margin-bottom:16px;color:#394a6b;font-size:1.12rem;}
.about-text strong{color:#2f6bff;}
.about-features{display:flex;flex-direction:column;gap:20px;}
.feature{padding:24px;border-radius:16px;border:1px solid var(--border);
  background:#fff;box-shadow:0 8px 26px rgba(47,107,255,.07);transition:.3s;}
.feature:hover{transform:translateY(-4px);}
.feature h3{color:#12204a;font-size:1.1rem;margin-bottom:8px;display:flex;align-items:center;gap:8px;}
.feature h3::before{content:"";width:8px;height:24px;background:var(--grad);border-radius:4px;}
.feature p{color:var(--muted);font-size:1.08rem;}

/* ---------- 服务 ---------- */
.service-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:26px;}
.service-card{padding:34px 28px;border-radius:18px;background:linear-gradient(180deg,#ffffff 0%,#f6faff 100%);border:1px solid var(--border);
  box-shadow:0 12px 32px rgba(47,107,255,.08),0 2px 8px rgba(47,107,255,.05);transition:.35s;position:relative;overflow:hidden;}
.service-card::before{content:"";position:absolute;top:0;left:0;right:0;height:4px;background:var(--grad);opacity:0;transition:.3s;}
.service-card::after{content:"";position:absolute;right:-60px;bottom:-60px;width:140px;height:140px;border-radius:50%;
  background:radial-gradient(circle,rgba(47,107,255,.08) 0%,transparent 70%);z-index:0;}
.service-card:hover{transform:translateY(-6px);box-shadow:0 18px 40px rgba(47,107,255,.14);}
.service-card:hover::before{opacity:1;}
.sc-top{display:flex;justify-content:space-between;align-items:flex-start;margin-bottom:16px;position:relative;z-index:1;}
.sc-num{font-size:1.02rem;font-weight:700;letter-spacing:2px;color:#2f6bff;background:rgba(47,107,255,.10);
  padding:5px 12px;border-radius:8px;}
.sc-ico{width:54px;height:54px;border-radius:14px;display:flex;align-items:center;justify-content:center;font-size:1.7rem;color:#2f6bff;
  background:linear-gradient(135deg,rgba(47,107,255,.14),rgba(0,208,255,.10));box-shadow:inset 0 0 0 1px rgba(47,107,255,.18),0 6px 16px rgba(47,107,255,.10);}
.service-card:hover .sc-ico{background:var(--grad);}
.service-card h3{font-size:1.32rem;color:#12204a;margin-bottom:6px;position:relative;z-index:1;}
.service-card .tagline{color:#2f6bff;font-weight:600;font-size:1.02rem;margin-bottom:12px;position:relative;z-index:1;}
.service-card ul{list-style:none;margin-top:4px;position:relative;z-index:1;}
.service-card li{color:#5c6b84;font-size:1.02rem;padding-left:18px;position:relative;margin-bottom:6px;}
.service-card li::before{content:"";position:absolute;left:0;top:10px;width:7px;height:7px;border-radius:50%;background:var(--grad);}

/* ---------- AI算力 ---------- */
.ai{background:linear-gradient(180deg,#f0f5ff 0%,#e7f0fd 100%);}
.ai .section-desc{color:var(--muted);}
.product-card{ text-align:center; padding:44px 40px;margin-bottom:34px;border-radius:24px;position:relative;overflow:hidden;
  background:linear-gradient(180deg,#ffffff 0%,#f4f9ff 100%);border:1px solid var(--border);
  box-shadow:0 24px 60px rgba(47,107,255,.10),0 4px 14px rgba(47,107,255,.05);
}
.product-card::before{content:"";position:absolute;top:-120px;right:-120px;width:340px;height:340px;border-radius:50%;
  background:radial-gradient(circle,rgba(0,208,255,.10) 0%,transparent 65%);pointer-events:none;}
.product-card::after{content:"";position:absolute;bottom:-140px;left:-120px;width:320px;height:320px;border-radius:50%;
  background:radial-gradient(circle,rgba(47,107,255,.10) 0%,transparent 65%);pointer-events:none;}
.product-badge{display:inline-block;padding:7px 20px;border-radius:30px;font-size:1.05rem;letter-spacing:1px;color:#fff;
  background:var(--grad);font-weight:700;margin-bottom:22px;}
.product-head{display:flex;flex-direction:column;align-items:center;gap:14px;margin-bottom:18px;position:relative;z-index:1;text-align:center;}
.ph-logo{width:58px;height:58px;border-radius:16px;display:flex;align-items:center;justify-content:center;flex-shrink:0;
  background:linear-gradient(135deg,#2f6bff,#00a8ff);box-shadow:0 8px 22px rgba(47,107,255,.28);font-weight:800;font-size:1.3rem;letter-spacing:1px;color:#fff;}
.ph-logo.gpu{background:linear-gradient(135deg,#0b2a5c,#2f6bff);box-shadow:0 8px 22px rgba(47,107,255,.28);}
.ph-text h3{font-size:clamp(1.3rem,2.5vw,1.8rem);font-weight:800;color:#12204a;background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;}
.ph-text p{color:#4a5a7d;margin-top:2px;font-size:1.05rem;font-weight:500;}
.product-desc{color:#394a6b;line-height:1.9;margin:0 auto 28px;font-size:1.12rem;position:relative;z-index:1;max-width:820px;text-align:center;}
.ai-grid{display:grid;gap:20px;position:relative;z-index:1;text-align:left;}
.ai-grid.cols4{grid-template-columns:repeat(4,1fr);}
.ai-grid.cols3{grid-template-columns:repeat(3,1fr);}
.ai-item{padding:26px 24px;border-radius:16px;border:1px solid var(--border);
  background:linear-gradient(180deg,#fff 0%,#f7fbff 100%);transition:.35s;position:relative;overflow:hidden;box-shadow:0 8px 22px rgba(47,107,255,.06);}
.ai-item::before{content:"";position:absolute;top:0;left:0;right:0;height:3px;background:var(--grad);opacity:0;transition:.3s;}
.ai-item:hover{box-shadow:0 14px 30px rgba(47,107,255,.12);transform:translateY(-5px);}
.ai-item:hover::before{opacity:1;}
.ai-item h4{color:#12204a;font-size:1.18rem;margin-bottom:8px;}
.ai-item p{color:var(--muted);font-size:1.04rem;line-height:1.8;}
.ai-ico{width:42px;height:42px;border-radius:11px;display:flex;align-items:center;justify-content:center;font-size:1.3rem;margin-bottom:14px;
  background:linear-gradient(135deg,rgba(47,107,255,.16),rgba(0,208,255,.12));box-shadow:0 5px 14px rgba(47,107,255,.10);}
.ai-adv{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:28px;position:relative;z-index:1;}
.adv-item{text-align:center;padding:26px 16px;border-radius:16px;border:1px solid rgba(47,107,255,.15);background:#fff;transition:.3s;box-shadow:0 6px 18px rgba(47,107,255,.05);}
.adv-item:hover{transform:translateY(-4px);box-shadow:0 14px 30px rgba(47,107,255,.12);}
.adv-ico{font-size:1.5rem;margin-bottom:10px;}
.adv-item span{display:block;font-size:1.1rem;font-weight:700;color:#2f6bff;margin-bottom:6px;}
.adv-item p{color:var(--muted);font-size:1.02rem;}
.ai-scene{margin-top:26px;position:relative;z-index:1;font-size:1.05rem;}
.ai-scene strong{color:#12204a;margin-right:4px;display:block;margin-bottom:10px;}
.ai-scene span{display:inline-block;margin:4px 8px 0 0;padding:7px 18px;border-radius:20px;color:#2f6bff;font-size:1rem;
  border:1px solid rgba(47,107,255,.2);background:rgba(47,107,255,.05);}
.gpu-feature{position:relative;z-index:1;margin-top:30px;padding:34px 30px;border-radius:18px;
  background:linear-gradient(135deg,rgba(47,107,255,.06),rgba(0,208,255,.05));border:1px solid var(--border);text-align:center;}
.gpu-tags{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;margin-bottom:18px;}
.gpu-tags span{padding:9px 22px;border-radius:30px;background:var(--grad);color:#fff;font-weight:600;font-size:1.05rem;}
.gpu-text p{color:#394a6b;font-size:1.08rem;}

/* ---------- 联系 ---------- */
.contact-grid{display:grid;grid-template-columns:1fr 1.05fr;gap:48px;}
.contact-info{display:flex;flex-direction:column;gap:20px;}
.c-item{display:flex;gap:16px;align-items:flex-start;padding:22px;border-radius:14px;background:linear-gradient(180deg,#fff,#f6faff);border:1px solid var(--border);box-shadow:0 8px 22px rgba(47,107,255,.07);}
.c-icon{font-size:1.6rem;background:linear-gradient(135deg,#eef4ff,#dfecff);width:52px;height:52px;flex-shrink:0;display:flex;align-items:center;justify-content:center;border-radius:12px;}
.c-item h4{color:#12204a;margin-bottom:4px;}
.c-item p{color:var(--muted);}
.contact-form{display:flex;flex-direction:column;gap:16px;padding:34px;background:linear-gradient(180deg,#fff,#f7fbff);border-radius:20px;border:1px solid var(--border);box-shadow:0 20px 48px rgba(47,107,255,.12),0 4px 14px rgba(47,107,255,.05);}
.contact-form input,.contact-form select,.contact-form textarea{
  width:100%;padding:14px 16px;border:1.5px solid #e3e9f5;border-radius:10px;font-size:.98rem;font-family:inherit;color:var(--text);transition:.2s;background:#fbfcff;
}
.contact-form input:focus,.contact-form select:focus,.contact-form textarea:focus{outline:none;border-color:#2f6bff;background:#fff;box-shadow:0 0 0 3px rgba(47,107,255,.12);}
.contact-form button{align-self:flex-start;border:none;cursor:pointer;}
.contact-form .form-privacy{font-size:12px;color:#8b96b5;line-height:1.6;margin:0;}

/* ---------- 页脚 ---------- */
.site-footer{background:#0d1530;color:#8fa0c4;padding:60px 0 28px;}
.footer-top{display:flex;justify-content:space-between;align-items:center;gap:24px;padding-bottom:34px;border-bottom:1px solid rgba(255,255,255,.08);}
.footer-brand img{height:64px;margin-bottom:10px;}
.footer-brand p{color:#cdd6ea;font-size:.98rem;letter-spacing:1px;}
.footer-links{display:flex;gap:28px;}
.footer-links a{color:#8fa0c4;transition:.2s;}
.footer-links a:hover{color:#fff;}
.footer-bottom{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;padding-top:26px;font-size:.9rem;}
.footer-bottom a{color:#8fa0c4;transition:.2s;}
.footer-bottom a:hover{color:#fff;}
.footer-beians{display:flex;align-items:center;gap:18px;flex-wrap:wrap;white-space:nowrap;}
.footer-beians a{display:inline-flex;align-items:center;gap:5px;text-decoration:none;}
.footer-beians a:hover{color:#fff;}
.footer-beians img{height:15px;width:auto;margin:0;}
.beian-sep{display:inline-block;width:1px;height:14px;background:rgba(143,160,196,.35);}

/* 返回顶部 */
.back-top{position:fixed;right:26px;bottom:30px;width:46px;height:46px;border-radius:50%;
  background:var(--grad);color:#fff;display:flex;align-items:center;justify-content:center;font-size:1.4rem;
  box-shadow:0 8px 20px rgba(47,107,255,.35);opacity:0;visibility:hidden;transition:.3s;z-index:900;}
.back-top.show{opacity:1;visibility:visible;}
.back-top:hover{transform:translateY(-4px);}

/* ---------- 动画 ---------- */
@keyframes fadeUp{from{opacity:0;transform:translateY(30px);}to{opacity:1;transform:none;}}

/* ---------- 响应式 ---------- */
@media(max-width:960px){
  .service-grid,.ai-grid.cols4,.ai-grid.cols3,.ai-adv{grid-template-columns:repeat(2,1fr);}
  .about-grid,.contact-grid{grid-template-columns:1fr;}
  .gpu-feature{padding:30px 22px;}
}
@media(max-width:640px){
  .nav-toggle{display:flex;}
  .nav-menu{
    position:fixed;top:70px;right:-100%;width:72%;max-width:300px;height:calc(100vh-70px);
    background:#ffffff;flex-direction:column;padding:30px;gap:26px;
    transition:.35s;align-items:flex-start;box-shadow:-6px 0 30px rgba(47,107,255,.12);border-left:1px solid var(--border);
  }
  .nav-menu.open{right:0;}
  .nav-cta{display:none;}
  .hero{padding:120px 0 50px;}
  .hero-content{text-align:center;margin:0 auto;}
  .hero-actions{justify-content:center;}
  .hero-stats{gap:22px;justify-content:space-between;}
  .stat .num{font-size:1.5rem;}
  .service-grid,.ai-grid.cols4,.ai-grid.cols3,.ai-adv{grid-template-columns:1fr;}
  .section{padding:70px 0;}
  .footer-top{flex-direction:column;align-items:flex-start;}
  .footer-bottom{flex-direction:column;}
}