/* ============================================================
   硕研官网 AIWEB —— 统一样式
   说明：全站仅使用此一份 CSS（+assets/js/app.js），
        零第三方依赖，样式集中、通用、体积小，便于部署 OSS。
   ============================================================ */

/* ---------- 主题变量 ---------- */
:root{
  --c-primary:#1b6bff;          /* 主色 科技蓝 */
  --c-cyan:#18d3ff;             /* 青 渐变 */
  --c-violet:#7b5bff;           /* 紫 点缀 */
  --c-dark:#0b1220;             /* 深底 */
  --c-dark-2:#101a30;
  --c-line:rgba(255,255,255,.10);
  --c-text:#e9f0ff;
  --c-muted:#93a4c4;
  --radius:14px;
  --shadow:0 20px 60px -30px rgba(0,0,0,.55);
  --grad:linear-gradient(135deg,#1b6bff 0%,#18d3ff 100%);
  --grad-dark:linear-gradient(135deg,rgba(27,107,255,.15),rgba(123,91,255,.12));
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",Roboto,Helvetica,Arial,sans-serif;
  background:var(--c-dark);
  color:var(--c-text);
  line-height:1.75;
  font-size:15px;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
ul{list-style:none}
::selection{background:rgba(27,107,255,.5);color:#fff}

.wrapper{max-width:1200px;margin:0 auto;padding:0 20px}

/* ---------- 分层渐变背景（无网格，纯色彩层次） ---------- */
.bg-grid{position:fixed;inset:0;z-index:-2;pointer-events:none;
  background:
    radial-gradient(80% 55% at 15% 0%,  rgba(27,107,255,.22), transparent 60%),
    radial-gradient(65% 50% at 88% 22%, rgba(24,211,255,.12), transparent 62%),
    radial-gradient(70% 60% at 75% 105%, rgba(123,91,255,.16), transparent 60%),
    linear-gradient(180deg, var(--c-dark) 0%, #0c1526 45%, #0a101d 100%);
  animation:breathe 16s ease-in-out infinite alternate;
}
@keyframes breathe{
  0%{opacity:.85}
  100%{opacity:1}
}
.bg-glow{position:fixed;inset:0;z-index:-1;pointer-events:none;
  background:radial-gradient(45% 38% at 50% -4%, rgba(27,107,255,.30), transparent 60%),
             radial-gradient(32% 28% at 8% 78%, rgba(24,211,255,.14), transparent 62%),
             radial-gradient(36% 30% at 96% 82%, rgba(123,91,255,.14), transparent 62%);
  filter:blur(6px);
  animation:glowDrift 18s ease-in-out infinite alternate;
}
@keyframes glowDrift{
  0%{transform:translateY(0)}
  100%{transform:translateY(-16px)}
}

/* ---------- 顶部导航 ---------- */
.nav{position:fixed;top:0;left:0;right:0;z-index:100;
  backdrop-filter:blur(12px);
  background:rgba(8,13,26,.72);
  border-bottom:1px solid var(--c-line);
  transition:.3s;
}
.nav-in{max-width:1200px;margin:0 auto;padding:0 20px;height:64px;display:flex;align-items:center;justify-content:space-between}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;letter-spacing:1px}
.brand .logo{height:34px;width:auto;filter:drop-shadow(0 4px 12px rgba(24,211,255,.4))}
.brand .dot{color:var(--c-cyan)}
.menu{display:flex;align-items:center;gap:6px}
.nav-link{position:relative;padding:8px 16px;border-radius:10px;color:var(--c-muted);font-size:15px;transition:.25s}
.nav-link:hover{color:#fff}
.nav-link.active{color:#fff}
.nav-link.active::after{content:"";position:absolute;left:16px;right:16px;bottom:2px;height:2px;
  background:var(--grad);border-radius:2px;box-shadow:0 0 12px rgba(24,211,255,.7)}
.nav-toggle{display:none;background:none;border:1px solid var(--c-line);color:#fff;font-size:20px;width:38px;height:38px;border-radius:10px;cursor:pointer}
@media(max-width:820px){
  .nav-toggle{display:block}
  .menu{position:absolute;top:64px;left:0;right:0;flex-direction:column;align-items:stretch;
    background:rgba(8,13,26,.98);padding:12px;border-bottom:1px solid var(--c-line);
    display:none}
  .menu.open{display:flex}
}

/* ---------- 通用 Section ---------- */
.section{padding:78px 0}
.section-tight{padding:44px 0}
.sec-head{text-align:center;max-width:760px;margin:0 auto 46px}
.sec-eyebrow{display:inline-block;padding:4px 14px;border-radius:30px;font-size:13px;letter-spacing:2px;
  color:var(--c-cyan);border:1px solid rgba(24,211,255,.35);background:rgba(24,211,255,.08);margin-bottom:14px}
.sec-title{font-size:34px;line-height:1.3;font-weight:800;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.sec-sub{color:var(--c-muted);margin-top:12px}

/* ---------- Hero ---------- */
.hero{position:relative;min-height:78vh;display:flex;align-items:center;padding:120px 0 70px;overflow:hidden}
.hero::before{content:"";position:absolute;inset:auto -10% -40% -10%;height:60%;z-index:-1;
  background:radial-gradient(50% 60% at 50% 100%,rgba(27,107,255,.35),transparent 70%);
  filter:blur(30px)}
.hero-badge{display:inline-flex;align-items:center;gap:8px;padding:6px 14px;border-radius:30px;font-size:13px;
  border:1px solid var(--c-line);color:var(--c-muted);background:rgba(255,255,255,.03);margin-bottom:20px}
.hero-badge i{width:8px;height:8px;border-radius:50%;background:var(--c-cyan);box-shadow:0 0 10px var(--c-cyan);animation:pulse 1.6s infinite}
@keyframes pulse{50%{opacity:.35}}
.hero-title{font-size:52px;line-height:1.18;font-weight:800;letter-spacing:1px;max-width:720px}
.hero-title .hl{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero-title .cursor{color:var(--c-cyan);animation:blink 1s steps(1) infinite}
@keyframes blink{50%{opacity:0}}
.hero-sub{color:var(--c-muted);font-size:17px;max-width:620px;margin:22px 0 34px}
.btn-row{display:flex;flex-wrap:wrap;gap:16px}
.btn{display:inline-flex;align-items:center;gap:8px;padding:13px 28px;border-radius:40px;font-size:15px;font-weight:600;
  transition:.3s;cursor:pointer;border:1px solid transparent}
.btn-primary{background:var(--grad);color:#fff;box-shadow:0 12px 30px -12px rgba(27,107,255,.8)}
.btn-primary:hover{transform:translateY(-3px);box-shadow:0 18px 40px -14px rgba(24,211,255,.9)}
.btn-ghost{color:#fff;border-color:var(--c-line);background:rgba(255,255,255,.03)}
.btn-ghost:hover{border-color:var(--c-cyan);color:var(--c-cyan)}
.hero-stats{display:flex;flex-wrap:wrap;gap:38px;margin-top:54px}
.stat b{font-size:30px;font-weight:800;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.stat span{display:block;color:var(--c-muted);font-size:13px;margin-top:2px}

/* 浮动粒子 */
.particles{position:absolute;inset:0;z-index:-1;overflow:hidden}
.particles i{position:absolute;bottom:-40px;width:8px;height:8px;border-radius:50%;
  background:var(--c-cyan);opacity:.5;animation:rise linear infinite}
@keyframes rise{
  0%{transform:translateY(0);opacity:0}
  10%{opacity:.6}
  100%{transform:translateY(-90vh);opacity:0}
}

/* ---------- 卡片 ---------- */
.grid{display:grid;gap:24px}
.g-2{grid-template-columns:repeat(2,1fr)}
.g-3{grid-template-columns:repeat(3,1fr)}
.g-4{grid-template-columns:repeat(4,1fr)}
@media(max-width:960px){.g-4{grid-template-columns:repeat(2,1fr)}.g-3{grid-template-columns:repeat(2,1fr)}}
@media(max-width:600px){.g-3,.g-2,.g-4{grid-template-columns:1fr}}

.card{position:relative;border:1px solid var(--c-line);border-radius:var(--radius);
  background:linear-gradient(160deg,rgba(255,255,255,.05),rgba(255,255,255,.015));
  padding:22px;transition:.35s;overflow:hidden}
.card::before{content:"";position:absolute;inset:0;background:var(--grad-dark);opacity:0;transition:.35s}
.card:hover{transform:translateY(-6px);border-color:rgba(24,211,255,.45);box-shadow:var(--shadow)}
.card:hover::before{opacity:1}
.card>*{position:relative}
.card .thumb{border-radius:10px;overflow:hidden;aspect-ratio:3/2;background:var(--grad-dark)}
.card .thumb img{width:100%;height:100%;object-fit:cover;transition:.5s}
.card:hover .thumb img{transform:scale(1.06)}
.card h4{font-size:17px;margin:14px 0 8px}
.card p{color:var(--c-muted);font-size:14px}
.card .tag{display:inline-block;font-size:12px;color:var(--c-cyan);border:1px solid rgba(24,211,255,.3);
  padding:2px 10px;border-radius:30px;margin-bottom:10px;background:rgba(24,211,255,.06)}
.more{display:inline-flex;align-items:center;gap:6px;margin-top:12px;color:var(--c-cyan);font-size:14px}
.more span{transition:.3s}
.more:hover span{transform:translateX(5px)}

/* ---------- 服务特性 ---------- */
.feat{text-align:center;padding:30px 18px}
.feat .ic{width:60px;height:60px;margin:0 auto 16px;border-radius:16px;display:flex;align-items:center;justify-content:center;
  font-size:26px;background:var(--grad-dark);border:1px solid var(--c-line)}
.feat h4{margin-bottom:8px}

/* ---------- 公告/新闻列表 ---------- */
.news-list li{display:flex;gap:12px;align-items:baseline;padding:12px 0;border-bottom:1px dashed var(--c-line)}
.news-list li:last-child{border-bottom:none}
.news-list .bdot{width:8px;height:8px;border-radius:50%;background:var(--grad);flex:none;margin-top:10px}
.news-list a{color:var(--c-muted);transition:.2s}
.news-list a:hover{color:#fff}
.news-list .date{color:var(--c-cyan);font-size:13px;flex:none}

/* ---------- 客户 logo ---------- */
.logo-wall{display:flex;flex-wrap:wrap;gap:18px;justify-content:center}
.logo-cell{width:160px;height:76px;display:flex;align-items:center;justify-content:center;
  border:1px solid var(--c-line);border-radius:12px;background:rgba(255,255,255,.03);padding:10px;transition:.3s}
.logo-cell:hover{border-color:rgba(24,211,255,.4);transform:translateY(-3px)}
.logo-cell img{max-height:52px;max-width:120px;object-fit:contain}

/* ---------- 详情面板 ---------- */
.panel{border:1px solid var(--c-line);border-radius:var(--radius);padding:30px;margin-bottom:26px;
  background:linear-gradient(160deg,rgba(255,255,255,.045),rgba(255,255,255,.012))}
.panel h2{font-size:22px;display:flex;align-items:center;gap:10px;flex-wrap:wrap}
.panel h2 .no{width:34px;height:34px;flex:none;border-radius:10px;background:var(--grad);color:#fff;display:flex;align-items:center;justify-content:center;font-size:16px}
.panel h3{font-size:17px;color:var(--c-cyan);margin:20px 0 8px}
.panel p{color:var(--c-muted);margin-bottom:8px}
.panel .imgs{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:14px;margin-top:10px}
.panel .imgs img{width:100%;border-radius:10px;border:1px solid var(--c-line);background:var(--grad-dark)}
.panel .feat-li li{padding:7px 0 7px 22px;position:relative;color:var(--c-muted)}
.panel .feat-li li::before{content:"▸";position:absolute;left:4px;color:var(--c-cyan)}

/* ---------- 页脚 ---------- */
.footer{border-top:1px solid var(--c-line);background:rgba(6,10,20,.6);padding:52px 0 0;margin-top:20px}
.f-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:34px;padding-bottom:30px}
.f-title{font-size:16px;margin-bottom:16px;letter-spacing:1px}
.f-links li{padding:5px 0}
.f-links a{color:var(--c-muted);transition:.2s}
.f-links a:hover{color:#fff}
.qr{width:96px;border-radius:10px;border:1px solid var(--c-line);background:#fff;padding:6px}
.field{width:100%;padding:11px 14px;border-radius:10px;border:1px solid var(--c-line);
  background:rgba(255,255,255,.03);color:#fff;margin-bottom:12px;outline:none;transition:.2s;font-family:inherit}
.field:focus{border-color:var(--c-cyan)}
textarea.field{resize:vertical;min-height:90px}
.f-copy{border-top:1px solid var(--c-line);padding:18px 0;display:flex;flex-wrap:wrap;gap:12px;justify-content:space-between;align-items:center;font-size:13px;color:var(--c-muted)}
.f-copy a{color:var(--c-muted)}
.f-copy a:hover{color:#fff}

/* ---------- 滚动显现 ---------- */
.rv{opacity:0;transform:translateY(24px);transition:opacity .7s ease,transform .7s ease}
.rv.in{opacity:1;transform:none}
.rv-d1{transition-delay:.08s}.rv-d2{transition-delay:.16s}.rv-d3{transition-delay:.24s}

/* ---------- 返回顶部 ---------- */
.to-top{position:fixed;right:22px;bottom:22px;z-index:99;width:44px;height:44px;border-radius:50%;
  background:var(--grad);color:#fff;display:flex;align-items:center;justify-content:center;font-size:18px;
  box-shadow:0 10px 24px -8px rgba(27,107,255,.8);opacity:0;pointer-events:none;transition:.3s}
.to-top.show{opacity:1;pointer-events:auto}
.to-top:hover{transform:translateY(-4px)}

/* ---------- 消息提示 ---------- */
.toast{position:fixed;top:84px;left:50%;transform:translateX(-50%) translateY(-16px);
  background:#0f1b33;border:1px solid var(--c-cyan);color:#fff;padding:12px 22px;border-radius:12px;
  opacity:0;pointer-events:none;transition:.3s;z-index:200;box-shadow:var(--shadow)}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}