/* ===== 和立 HeLi 主页样式 — 明亮科技蓝 + 青色 + AI 感 ===== */
:root{
  --blue:#2563eb; --blue-d:#1d4ed8; --blue-l:#3b82f6;
  --cyan:#06b6d4; --cyan-l:#22d3ee;
  --ink:#0f172a; --ink-2:#334155; --muted:#64748b;
  --bg:#f3f7ff; --card:#ffffff; --line:#e3ebf9;
  --grad:linear-gradient(120deg,#2563eb 0%,#3b82f6 45%,#22d3ee 100%);
  --grad-soft:linear-gradient(120deg,#eff5ff,#e8f6ff);
  --shadow:0 18px 50px -18px rgba(37,99,235,.30);
  --radius:20px;
  --maxw:1180px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0; color:var(--ink);
  background:
    radial-gradient(58% 46% at 86% 2%, rgba(34,211,238,.16), transparent 62%),
    radial-gradient(64% 56% at 8% 16%, rgba(59,130,246,.13), transparent 60%),
    radial-gradient(50% 50% at 50% 110%, rgba(99,179,237,.12), transparent 60%),
    linear-gradient(180deg,#edf4ff 0%,#f4f8ff 48%,#eaf3ff 100%);
  background-attachment:fixed;
  font-family:"PingFang SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  line-height:1.65; overflow-x:hidden; position:relative;
}
a{color:inherit;text-decoration:none}
img{display:block;max-width:100%}

/* 背景动态层 */
#bg-particles{position:fixed;inset:0;z-index:0;pointer-events:none;opacity:.4}
.bg-grid{position:fixed;inset:0;z-index:0;pointer-events:none;opacity:.55;
  background:url(mesh.svg) center top/cover no-repeat;
  -webkit-mask-image:radial-gradient(ellipse 95% 80% at 50% 6%,#000 22%,transparent 84%);
  mask-image:radial-gradient(ellipse 95% 80% at 50% 6%,#000 22%,transparent 84%)}
.ai-graphic{position:fixed;z-index:0;pointer-events:none}
.ai-left{width:480px;left:-140px;top:15%;opacity:.78;animation:floatY 14s ease-in-out infinite}
.ai-br{width:340px;right:-78px;bottom:-66px;opacity:.55;animation:floatY 18s ease-in-out infinite reverse}
@keyframes floatY{50%{transform:translateY(-22px)}}
.bg-deco{position:fixed;z-index:0;pointer-events:none;width:700px;height:700px;top:-140px;right:-170px;opacity:.55;animation:spin 70s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.bg-glow{position:fixed;border-radius:50%;filter:blur(85px);z-index:0;pointer-events:none;opacity:.5}
.bg-glow-1{width:540px;height:540px;background:radial-gradient(circle,#6aa6ff,transparent 70%);top:-170px;right:-120px;animation:float1 16s ease-in-out infinite}
.bg-glow-2{width:470px;height:470px;background:radial-gradient(circle,#5ee7f7,transparent 70%);bottom:-180px;left:-130px;animation:float2 19s ease-in-out infinite}
.bg-glow-3{width:400px;height:400px;background:radial-gradient(circle,#9cc4ff,transparent 70%);top:42%;right:6%;opacity:.4;animation:float1 24s ease-in-out infinite}
@keyframes float1{50%{transform:translate(-40px,50px)}}
@keyframes float2{50%{transform:translate(50px,-40px)}}

/* 容器与通用 */
.section{position:relative;z-index:1;max-width:var(--maxw);margin:0 auto;padding:96px 24px}
.kicker{display:inline-block;font-size:13px;font-weight:700;letter-spacing:2px;color:var(--cyan);background:rgba(6,182,212,.10);padding:5px 12px;border-radius:999px;margin-bottom:14px}
.section-head{text-align:center;max-width:680px;margin:0 auto 56px}
.section-head h2{font-size:clamp(26px,3.4vw,40px);margin:.2em 0 .35em;letter-spacing:-.5px}
.section-head p{color:var(--muted);font-size:17px;margin:0}
.grad{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}

/* 导航 */
.nav{position:sticky;top:0;z-index:50;display:flex;align-items:center;justify-content:space-between;
  max-width:var(--maxw);margin:0 auto;padding:14px 24px;
  backdrop-filter:saturate(160%) blur(14px);background:rgba(243,247,255,.72);border-bottom:1px solid transparent;transition:.3s}
.nav.scrolled{background:rgba(255,255,255,.82);border-bottom:1px solid var(--line);box-shadow:0 6px 24px -16px rgba(37,99,235,.4)}
.brand{display:flex;align-items:center;gap:11px}
.brand-logo{width:42px;height:42px;filter:drop-shadow(0 5px 11px rgba(37,99,235,.4))}
.brand-text{font-weight:800;font-size:20px;letter-spacing:.5px}
.brand-text b{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent;margin-left:3px}
.brand-text i{font-style:normal;font-size:12px;font-weight:700;color:#fff;background:var(--grad);padding:2px 6px;border-radius:6px;margin-left:6px;vertical-align:middle}
.nav-links{display:flex;align-items:center;gap:30px;font-weight:600;font-size:15px}
.nav-links a{color:var(--ink-2);transition:.2s}
.nav-links a:hover{color:var(--blue)}
.nav-cta{color:#fff!important;background:var(--grad);padding:9px 20px;border-radius:999px;box-shadow:0 10px 22px -10px rgba(37,99,235,.7)}
.nav-cta:hover{filter:brightness(1.05);transform:translateY(-1px)}
.nav-burger{display:none;flex-direction:column;gap:5px;background:none;border:0;cursor:pointer;padding:8px}
.nav-burger span{width:24px;height:2.5px;background:var(--ink);border-radius:2px;transition:.3s}

/* HERO */
.hero{position:relative;z-index:1;max-width:var(--maxw);margin:0 auto;padding:90px 24px 70px;text-align:center}
.badge{display:inline-flex;align-items:center;gap:8px;font-size:13px;font-weight:700;color:var(--blue-d);
  background:#fff;border:1px solid var(--line);padding:7px 16px;border-radius:999px;box-shadow:var(--shadow)}
.badge .dot{width:8px;height:8px;border-radius:50%;background:var(--cyan);box-shadow:0 0 0 4px rgba(34,211,238,.25);animation:pulse 1.8s infinite}
@keyframes pulse{50%{box-shadow:0 0 0 8px rgba(34,211,238,0)}}
.hero-title{font-size:clamp(34px,6vw,68px);line-height:1.08;letter-spacing:-1.5px;margin:26px 0 18px;font-weight:800}
.hero-sub{color:var(--muted);font-size:clamp(15px,1.7vw,19px);max-width:760px;margin:0 auto 34px;text-wrap:pretty}
.hero-actions{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;gap:9px;font-weight:700;font-size:16px;padding:14px 30px;border-radius:999px;cursor:pointer;transition:.25s;border:1px solid transparent}
.btn svg{transition:.25s}
.btn-primary{color:#fff;background:var(--grad);box-shadow:0 16px 34px -12px rgba(37,99,235,.75)}
.btn-primary:hover{transform:translateY(-2px);filter:brightness(1.05)}
.btn-primary:hover svg{transform:translateX(4px)}
.btn-ghost{color:var(--blue-d);background:#fff;border-color:var(--line);box-shadow:var(--shadow)}
.btn-ghost:hover{transform:translateY(-2px);border-color:#bcd3ff}
.hero-stats{display:inline-flex;align-items:center;gap:26px;margin-top:48px;padding:18px 30px;background:rgba(255,255,255,.7);border:1px solid var(--line);border-radius:18px;backdrop-filter:blur(8px);box-shadow:var(--shadow)}
.hero-stats div{display:flex;flex-direction:column;line-height:1.2}
.hero-stats b{font-size:24px;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero-stats span{font-size:13px;color:var(--muted)}
.hero-stats .sep{width:1px;height:30px;background:var(--line)}

/* 产品卡片 */
.cards{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.card{position:relative;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:30px 26px;
  box-shadow:0 10px 40px -22px rgba(37,99,235,.4);transition:.3s;overflow:hidden}
.card::before{content:"";position:absolute;inset:0;background:var(--grad-soft);opacity:0;transition:.3s;z-index:0}
.card:hover{transform:translateY(-7px);border-color:#c8dbff;box-shadow:0 28px 56px -24px rgba(37,99,235,.55)}
.card:hover::before{opacity:.6}
.card>*{position:relative;z-index:1}
.card-ico{width:56px;height:56px;border-radius:15px;display:grid;place-items:center;color:#fff;margin-bottom:18px;box-shadow:0 12px 24px -10px rgba(37,99,235,.6)}
.ico-blue{background:linear-gradient(135deg,#2563eb,#3b82f6)}
.ico-cyan{background:linear-gradient(135deg,#0891b2,#22d3ee)}
.ico-grad{background:var(--grad)}
.card-logo{width:64px;height:64px;margin-bottom:18px;filter:drop-shadow(0 10px 18px rgba(37,99,235,.38))}
.card h3{font-size:23px;margin:0 0 4px}
.card-tag{color:var(--cyan);font-weight:700;font-size:14px;margin:0 0 16px}
.feat{list-style:none;padding:0;margin:0 0 22px}
.feat li{position:relative;padding-left:26px;margin:11px 0;color:var(--ink-2);font-size:15px}
.feat li::before{content:"";position:absolute;left:0;top:8px;width:14px;height:14px;border-radius:50%;
  background:var(--grad);box-shadow:0 0 0 3px rgba(37,99,235,.12)}
.feat li::after{content:"";position:absolute;left:4px;top:11px;width:5px;height:8px;border:solid #fff;border-width:0 2px 2px 0;transform:rotate(40deg)}
.card-link{font-weight:700;color:var(--blue);font-size:15px;transition:.2s}
.card-link:hover{letter-spacing:.5px}

/* 能力条 */
.strip{position:relative;z-index:1;max-width:var(--maxw);margin:0 auto;display:grid;grid-template-columns:repeat(4,1fr);gap:18px;padding:0 24px}
.strip-item{background:var(--grad);border-radius:16px;padding:22px 24px;color:#fff;box-shadow:0 18px 40px -18px rgba(37,99,235,.6)}
.strip-item b{display:block;font-size:18px}
.strip-item span{font-size:13.5px;opacity:.9}

/* AI 引擎流程 */
.flow-row{display:flex;align-items:center;justify-content:center;flex-wrap:wrap;max-width:1000px;margin:0 auto}
.flow-node{flex:0 0 210px;text-align:center;background:var(--card);border:1px solid var(--line);border-radius:18px;padding:26px 18px;box-shadow:0 14px 40px -22px rgba(37,99,235,.45)}
.flow-ic{width:58px;height:58px;margin:0 auto 12px;border-radius:15px;display:grid;place-items:center;color:#fff;background:var(--grad);box-shadow:0 12px 24px -10px rgba(37,99,235,.6)}
.flow-node b{display:block;font-size:18px;margin-bottom:4px}
.flow-node span{font-size:13px;color:var(--muted)}
.flow-line{flex:1 1 50px;min-width:46px;height:3px;position:relative;border-radius:3px;margin:0 8px;
  background:linear-gradient(90deg,#bcd7ff,#22d3ee)}
.flow-line i{position:absolute;top:50%;left:0;width:10px;height:10px;border-radius:50%;background:#22d3ee;
  box-shadow:0 0 0 5px rgba(34,211,238,.22);transform:translate(-50%,-50%);animation:flowdot 2.6s linear infinite}
@keyframes flowdot{from{left:0}to{left:100%}}
.flow-core{flex:0 0 200px;text-align:center}
.flow-core img{width:168px;margin:0 auto -6px;display:block}
.flow-core span{display:block;font-weight:800;font-size:16px;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}

/* 下载 */
.dl-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;align-items:stretch}
.dl-badge{position:absolute;top:14px;right:14px;font-size:12px;font-weight:800;letter-spacing:.5px;padding:3px 11px;border-radius:999px}
.dl-badge.pro{color:#fff;background:var(--grad)}
.dl-badge.lite{color:var(--blue-d);background:#eaf2ff;border:1px solid #d4e4ff}
.dl-card{position:relative;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:28px 20px;text-align:center;box-shadow:0 10px 40px -24px rgba(37,99,235,.4);transition:.3s}
.dl-card:hover{transform:translateY(-5px);box-shadow:0 24px 50px -24px rgba(37,99,235,.5)}
.dl-ico{width:66px;height:66px;margin:0 auto 14px;filter:drop-shadow(0 8px 16px rgba(37,99,235,.4))}
.dl-card h4{margin:0 0 4px;font-size:20px}
.dl-desc{color:var(--muted);margin:0 0 18px;font-size:14px}
.dl-btn{width:100%;justify-content:center;font-size:15px;padding:12px}
.dl-btn[data-disabled]{opacity:.55;pointer-events:none;filter:grayscale(.2)}
.dl-code{margin:14px 0 0;font-size:14px;color:var(--ink-2)}
.dl-code code{background:#eef4ff;color:var(--blue-d);padding:3px 10px;border-radius:7px;font-weight:700;letter-spacing:1px}
.dl-note{text-align:center;color:var(--muted);font-size:14px;margin-top:30px}

/* 关于 + 免责 */
.about-grid{display:grid;grid-template-columns:1.1fr 1fr;gap:48px;align-items:start}
.about p{color:var(--ink-2);font-size:16px}
.disclaimer{background:var(--card);border:1px solid var(--line);border-left:4px solid var(--cyan);border-radius:16px;padding:28px 30px;box-shadow:var(--shadow)}
.disclaimer h3{margin:0 0 14px;font-size:19px}
.disclaimer ul{margin:0;padding-left:18px;color:var(--muted);font-size:14.5px}
.disclaimer li{margin:10px 0}

/* 页脚 */
.footer{position:relative;z-index:1;background:#0d1b3a;color:#cdd8f0;margin-top:60px}
.footer-inner{max-width:var(--maxw);margin:0 auto;padding:40px 24px;display:flex;justify-content:space-between;align-items:center;gap:24px;flex-wrap:wrap}
.footer-brand{display:flex;align-items:center;gap:14px}
.footer-brand img{width:48px;height:48px;filter:drop-shadow(0 4px 10px rgba(0,0,0,.35))}
.footer-brand b{display:block;font-size:18px;color:#fff}
.footer-brand span{font-size:13px;color:#8ea3cf}
.footer-meta{display:flex;flex-direction:column;gap:6px;text-align:right;font-size:13.5px;color:#8ea3cf}
.footer-meta i{font-style:normal;color:#cdd8f0}

/* 滚动揭示动画 */
.reveal{opacity:0;transform:translateY(26px);transition:.7s cubic-bezier(.2,.7,.2,1)}
.reveal.in{opacity:1;transform:none}

/* 响应式 */
@media(max-width:900px){
  .cards{grid-template-columns:1fr}
  .dl-grid{grid-template-columns:repeat(2,1fr)}
  .strip{grid-template-columns:repeat(2,1fr)}
  .about-grid{grid-template-columns:1fr;gap:28px}
  .nav-links{position:fixed;inset:64px 0 auto 0;flex-direction:column;background:rgba(255,255,255,.97);
    padding:18px 24px;gap:18px;border-bottom:1px solid var(--line);transform:translateY(-130%);transition:.35s;box-shadow:0 20px 40px -20px rgba(0,0,0,.2)}
  .nav-links.open{transform:none}
  .nav-burger{display:flex}
  .footer-inner{flex-direction:column;text-align:center}
  .footer-meta{text-align:center}
  .ai-left{width:300px;left:-120px;top:7%;opacity:.42}
  .ai-br{width:220px;opacity:.4}
  .flow-node,.flow-core{flex:0 0 100%}
  .flow-line{flex-basis:100%;height:2px;margin:8px 0}
  .flow-line i{animation:none;left:50%}
}
@media(max-width:520px){
  .hero-stats{gap:16px;padding:14px 18px}
  .section{padding:64px 18px}
  .hero{padding:60px 18px 40px}
  .dl-grid{grid-template-columns:1fr}
}