*{margin:0;padding:0;box-sizing:border-box}
:root{--primary:#10a37f;--primary-dark:#0d8a6a;--accent:#19c37d;--dark:#0d0d0d;--card:#1a1a1a;--text:#ececf1;--muted:#9b9ba5;--white:#fff;--line:rgba(255,255,255,.08);--r:14px}
html{scroll-behavior:smooth}
body{font-family:"PingFang SC","Microsoft YaHei",-apple-system,BlinkMacSystemFont,sans-serif;background:var(--dark);color:var(--text);line-height:1.65}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.wrap{width:min(1100px,92%);margin:0 auto}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:13px 26px;border-radius:10px;font-weight:600;font-size:15px;border:none;cursor:pointer;transition:.2s}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-dark)}
.btn-outline{background:transparent;border:1.5px solid var(--primary);color:var(--primary)}
.btn-outline:hover{background:var(--primary);color:#fff}
.btn-sm{padding:8px 16px;font-size:13px}

header{position:fixed;top:0;left:0;right:0;z-index:100;background:rgba(13,13,13,.92);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:64px}
.logo{display:flex;align-items:center;gap:8px;font-weight:700;font-size:18px}
.logo-mark{width:32px;height:32px;border-radius:8px;background:linear-gradient(135deg,var(--primary),var(--accent));display:flex;align-items:center;justify-content:center;font-weight:800;color:#fff;font-size:16px}
.menu{display:flex;align-items:center;gap:4px;list-style:none}
.menu a{padding:8px 12px;font-size:14px;color:var(--muted);border-radius:8px}
.menu a:hover,.menu a.on{color:#fff}
.ham{display:none;background:0;border:0;color:#fff;font-size:22px;cursor:pointer}

.hero{padding:120px 0 70px;background:radial-gradient(ellipse at 20% 0%,rgba(16,163,127,.15),transparent 50%)}
.hero-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:40px;align-items:center}
.hero h1{font-size:clamp(2rem,4.5vw,2.8rem);font-weight:800;line-height:1.15;margin-bottom:16px}
.hero h1 span{color:var(--accent)}
.hero .lead{color:var(--muted);font-size:1.05rem;margin-bottom:24px;max-width:480px}
.hero-btns{display:flex;gap:12px;flex-wrap:wrap}
.chat-demo{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:20px;min-height:280px}
.chat-header{font-size:13px;color:var(--muted);margin-bottom:14px;display:flex;align-items:center;gap:8px}
.chat-header .dot{width:8px;height:8px;border-radius:50%;background:var(--accent)}
.msg{margin-bottom:12px;max-width:85%;padding:10px 14px;border-radius:12px;font-size:14px;line-height:1.5}
.msg.user{background:var(--primary);color:#fff;margin-left:auto;border-bottom-right-radius:4px}
.msg.ai{background:#2a2a2a;border-bottom-left-radius:4px}
.chat-input{margin-top:16px;display:flex;gap:8px}
.chat-input input{flex:1;background:#111;border:1px solid var(--line);border-radius:8px;padding:10px 12px;color:#fff;font-size:13px}
.chat-input button{background:var(--primary);color:#fff;border:0;border-radius:8px;padding:0 14px;cursor:pointer}

.sec{padding:70px 0}
.sec-title{text-align:center;margin-bottom:36px}
.sec-title h2{font-size:clamp(1.5rem,3vw,2rem);font-weight:800;margin-bottom:8px}
.sec-title p{color:var(--muted)}
.alt{background:rgba(255,255,255,.02)}

.features{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:16px}
.feat{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:22px}
.feat h3{font-size:1rem;margin:10px 0 8px}
.feat p{font-size:13px;color:var(--muted)}
.feat-ico{font-size:24px}

.scenarios{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.scen{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:20px}
.scen h3{font-size:1rem;margin-bottom:8px}
.scen p{font-size:13px;color:var(--muted)}

.faq{max-width:700px;margin:0 auto}
.faq-item{border:1px solid var(--line);border-radius:10px;margin-bottom:10px;background:var(--card);overflow:hidden}
.faq-q{width:100%;text-align:left;padding:14px 16px;background:0;border:0;color:#fff;font-weight:600;cursor:pointer;font-size:14px}
.faq-a{max-height:0;overflow:hidden;transition:.3s}
.faq-item.open .faq-a{max-height:200px}
.faq-a div{padding:0 16px 14px;font-size:13px;color:var(--muted)}

.cta{padding:60px 0;text-align:center;background:linear-gradient(135deg,rgba(16,163,127,.2),transparent)}
.cta h2{font-size:1.6rem;margin-bottom:10px}
.cta p{color:var(--muted);margin-bottom:20px}

footer{padding:40px 0 24px;border-top:1px solid var(--line);font-size:13px;color:var(--muted)}
.foot-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:24px;margin-bottom:24px}
.foot-grid h4{color:#fff;margin-bottom:10px;font-size:14px}
.foot-grid ul{list-style:none}
.foot-grid li{margin-bottom:6px}
.foot-bot{padding-top:16px;border-top:1px solid var(--line);display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px}

@media(max-width:900px){
.ham{display:block}
.menu{position:fixed;top:64px;left:0;right:0;background:var(--dark);flex-direction:column;padding:16px;transform:translateY(-120%);opacity:0;visibility:hidden;transition:.3s;border-bottom:1px solid var(--line)}
.menu.open{transform:none;opacity:1;visibility:visible}
.hero-grid,.scenarios{grid-template-columns:1fr}
.foot-grid{grid-template-columns:1fr}
}