:root{
  --primary:#ff6a2b;
  --primary-deep:#ef5719;
  --dark:#161a26;
  --bg:#f5f6f8;
  --card:#ffffff;
  --border:#e6e8ee;
  --text:#242832;
  --muted:#59606e;
  --radius:14px;
  --shadow:0 10px 30px rgba(22,26,38,.08);
  --nav-h:64px;
  --icon-bg:#fff1e8;
  --star:#ffa41c;
  --text-soft:#aab0bd;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:"PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.7;padding-top:var(--nav-h);-webkit-font-smoothing:antialiased}
a{text-decoration:none;color:inherit}
img{display:block;width:100%;height:auto}
button{font-family:inherit;cursor:pointer}

/* nav */
.nav{position:fixed;top:0;left:0;right:0;height:var(--nav-h);background:var(--card);border-bottom:1px solid var(--border);z-index:100}
.nav-inner{max-width:1200px;height:100%;margin:0 auto;padding:0 24px;display:flex;align-items:center;gap:20px}
.logo{font-size:26px;font-weight:800;color:var(--primary);flex-shrink:0;letter-spacing:.5px}
.menu{display:flex;align-items:center;gap:16px;margin:0 auto;font-size:14px}
.menu a{padding:4px 2px;transition:color .2s}
.menu a:hover{color:var(--primary)}
.nav-btn{font-size:13px;font-weight:600;color:#fff;background:var(--primary);padding:7px 13px;border-radius:999px;flex-shrink:0;transition:background .2s,transform .2s}
.nav-btn:hover{background:var(--primary-deep);transform:translateY(-1px)}

/* hero */
.hero{background:linear-gradient(180deg,#fff3ea 0%,var(--bg) 100%)}
.hero-inner{max-width:1200px;margin:0 auto;padding:76px 24px;display:flex;align-items:center;gap:56px}
.hero-text{flex:1;min-width:0}
.bubble{display:inline-flex;align-items:center;background:var(--card);border:1px solid var(--border);color:var(--primary);font-size:13px;font-weight:600;padding:6px 14px;border-radius:999px;position:relative;box-shadow:0 4px 12px rgba(255,106,43,.12)}
.bubble::after{content:"";position:absolute;left:26px;bottom:-6px;width:10px;height:10px;background:var(--card);border-right:1px solid var(--border);border-bottom:1px solid var(--border);transform:rotate(45deg)}
.hero-text h1{font-size:44px;line-height:1.3;font-weight:800;margin-top:18px;letter-spacing:1px}
.hero-text p{margin:20px 0 30px;font-size:16px;color:var(--muted);max-width:560px}
.hero-btns{display:flex;gap:16px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:13px 28px;border-radius:999px;font-size:15px;font-weight:600;color:#fff;background:var(--primary);box-shadow:0 8px 20px rgba(255,106,43,.28);transition:background .2s,transform .2s,box-shadow .2s;white-space:nowrap}
.btn:hover{background:var(--primary-deep);transform:translateY(-2px);box-shadow:0 10px 24px rgba(255,106,43,.35)}
.btn-ghost{background:var(--card);color:var(--primary);border:1px solid var(--primary);box-shadow:none}
.btn-ghost:hover{background:#fff7f2;box-shadow:0 8px 20px rgba(255,106,43,.15)}
.hero-img{width:340px;flex-shrink:0}
.hero-img img{border-radius:18px;box-shadow:0 16px 40px rgba(22,26,38,.14)}

/* section common */
.section{padding:80px 0}
.wrap{max-width:1200px;margin:0 auto;padding:0 24px}
.sec-head{text-align:center;margin-bottom:48px}
.sec-head h2{font-size:32px;font-weight:800;letter-spacing:.5px}
.sec-head p{color:var(--muted);margin-top:10px;font-size:15px}
.sec-head.light h2{color:#fff}
.sec-head.light p{color:var(--text-soft)}

/* works */
.works-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:24px}
.work-card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;box-shadow:0 2px 10px rgba(22,26,38,.04);transition:transform .25s,box-shadow .25s}
.work-card:hover{transform:translateY(-6px);box-shadow:var(--shadow)}

/* intro */
.intro-box{max-width:860px;margin:0 auto;background:var(--card);border:1px solid var(--border);border-radius:20px;padding:44px 48px;box-shadow:0 2px 10px rgba(22,26,38,.04)}
.intro-box p{font-size:16px;color:var(--text);margin-bottom:16px}
.intro-box p:last-of-type{margin-bottom:24px}
.intro-points{list-style:none;display:flex;gap:16px;flex-wrap:wrap}
.intro-points li{display:inline-flex;align-items:center;gap:8px;background:var(--bg);border:1px solid var(--border);color:var(--text);font-size:14px;font-weight:600;padding:9px 18px;border-radius:999px}
.intro-points li::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--primary);flex-shrink:0}

/* features */
.features-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.feature-card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:30px 26px;transition:transform .25s,box-shadow .25s}
.feature-card:hover{transform:translateY(-6px);box-shadow:var(--shadow)}
.f-icon{width:52px;height:52px;border-radius:14px;background:var(--icon-bg);color:var(--primary);display:flex;align-items:center;justify-content:center;margin-bottom:18px}
.f-icon svg{width:26px;height:26px}
.feature-card h3{font-size:18px;font-weight:700;margin-bottom:10px}
.feature-card p{font-size:14px;color:var(--muted)}

/* compare */
.cmp-box{max-width:900px;margin:0 auto;background:var(--card);border:1px solid var(--border);border-radius:20px;overflow:hidden;box-shadow:0 2px 10px rgba(22,26,38,.04)}
.cmp{width:100%;border-collapse:collapse;text-align:center;font-size:15px}
.cmp th{background:var(--dark);color:#fff;font-weight:600;padding:16px 20px}
.cmp th:first-child{text-align:left}
.cmp td{padding:15px 20px;border-top:1px solid var(--border);color:var(--muted)}
.cmp td:first-child{text-align:left;font-weight:600;color:var(--text)}
.cmp tbody tr:nth-child(even){background:#fafbfc}
.cmp td:nth-child(2){color:var(--primary);font-weight:600}

/* data */
.data{background:var(--dark)}
.data-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:32px;text-align:center}
.data-item b{display:block;font-size:42px;font-weight:800;color:var(--primary);line-height:1.2}
.data-item span{display:block;margin-top:8px;font-size:14px;color:var(--text-soft)}

/* reviews */
.review-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}
.review-card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:24px;transition:transform .25s,box-shadow .25s}
.review-card:hover{transform:translateY(-6px);box-shadow:var(--shadow)}
.review-top{display:flex;align-items:center;gap:12px;margin-bottom:14px}
.avatar{width:44px;height:44px;border-radius:50%;background:var(--primary);color:#fff;font-size:18px;font-weight:700;display:flex;align-items:center;justify-content:center;flex-shrink:0}
.review-user .name{font-size:15px;font-weight:700}
.stars{font-size:13px;color:var(--star);letter-spacing:2px;margin-top:2px}
.review-text{font-size:14px;color:var(--muted);line-height:1.8}

/* update */
.update-wrap{display:flex;gap:32px;max-width:1000px;margin:0 auto}
.update-info{width:300px;flex-shrink:0;background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:36px 24px;text-align:center;display:flex;flex-direction:column;justify-content:center;box-shadow:0 2px 10px rgba(22,26,38,.04)}
.update-ver{font-size:40px;font-weight:800;color:var(--primary);line-height:1.2}
.update-date{color:var(--muted);font-size:14px;margin-top:12px}
.update-list{flex:1;background:var(--card);border:1px solid var(--border);border-radius:var(--radius);padding:30px 32px;list-style:none;box-shadow:0 2px 10px rgba(22,26,38,.04)}
.update-list li{position:relative;padding:11px 0 11px 24px;font-size:15px;border-bottom:1px dashed var(--border)}
.update-list li:last-child{border-bottom:none}
.update-list li::before{content:"";position:absolute;left:4px;top:22px;width:7px;height:7px;border-radius:50%;background:var(--primary)}

/* faq */
.faq{max-width:820px;margin:0 auto}
.faq-item{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);margin-bottom:14px;transition:box-shadow .25s}
.faq-item.open{box-shadow:var(--shadow)}
.faq-item h3{font-size:16px;font-weight:600;padding:18px 24px;cursor:pointer;display:flex;justify-content:space-between;align-items:center;gap:16px;user-select:none;transition:color .2s}
.faq-item h3:hover{color:var(--primary)}
.faq-item h3::after{content:"+";font-size:22px;font-weight:400;color:var(--primary);flex-shrink:0;transition:transform .3s;line-height:1}
.faq-item.open h3::after{transform:rotate(45deg)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .35s ease}
.faq-item.open .faq-answer{max-height:300px}
.faq-answer p{padding:0 24px 20px;color:var(--muted);font-size:14px}

/* download */
.download{background:linear-gradient(180deg,var(--bg) 0%,#fff1e6 100%)}
.download-box{max-width:860px;margin:0 auto;background:var(--card);border:1px solid var(--border);border-radius:22px;padding:52px 40px;text-align:center;box-shadow:var(--shadow)}
.download-box h1{font-size:36px;font-weight:800;letter-spacing:1px}
.meta{margin-top:14px;font-size:14px;color:var(--muted)}
.download-btns{display:flex;justify-content:center;gap:16px;margin-top:32px}
.tip{margin-top:24px;font-size:14px;color:var(--muted)}

/* footer */
.footer{background:var(--dark);color:var(--text-soft);text-align:center;padding:28px 20px;font-size:13px}
.footer a{color:#fff;transition:color .2s}
.footer a:hover{color:var(--primary)}

/* back top */
.back-top{position:fixed;right:24px;bottom:32px;width:46px;height:46px;border-radius:50%;border:none;background:var(--primary);color:#fff;font-size:20px;display:flex;align-items:center;justify-content:center;box-shadow:0 8px 20px rgba(255,106,43,.35);opacity:0;visibility:hidden;transform:translateY(10px);transition:opacity .3s,transform .3s,visibility .3s;z-index:99}
.back-top.show{opacity:1;visibility:visible;transform:translateY(0)}
.back-top:hover{background:var(--primary-deep)}

/* responsive */
@media(max-width:1024px){
  .works-grid,.review-grid{grid-template-columns:repeat(2,1fr)}
  .features-grid{grid-template-columns:repeat(2,1fr)}
  .data-grid{grid-template-columns:repeat(2,1fr)}
  .menu{gap:10px;font-size:13px}
}
@media(max-width:768px){
  :root{--nav-h:56px}
  .menu{display:none}
  .nav-inner{padding:0 20px;gap:12px}
  .logo{font-size:22px}
  .nav-btn{font-size:12px;padding:6px 12px;margin-left:auto}
  .hero-inner{flex-direction:column;padding:48px 20px 56px;gap:36px;text-align:center}
  .hero-text h1{font-size:30px;margin-top:14px}
  .hero-text p{margin:16px auto 26px;font-size:15px}
  .hero-btns{flex-direction:column;width:100%;gap:12px}
  .hero-btns .btn{width:100%}
  .bubble{margin:0 auto}
  .hero-img{width:100%;max-width:360px;margin:0 auto}
  .section{padding:56px 0}
  .wrap{padding:0 20px}
  .sec-head{margin-bottom:36px}
  .sec-head h2{font-size:26px}
  .works-grid,.features-grid,.review-grid{grid-template-columns:1fr}
  .data-grid{grid-template-columns:1fr 1fr;gap:28px}
  .data-item b{font-size:32px}
  .intro-box{padding:30px 24px}
  .intro-points{flex-direction:column;align-items:center;gap:10px}
  .update-wrap{flex-direction:column}
  .update-info{width:100%;padding:28px 24px}
  .update-list{padding:22px 24px}
  .cmp{font-size:12px}
  .cmp th,.cmp td{padding:12px 8px}
  .download-box{padding:40px 20px}
  .download-box h1{font-size:26px}
  .meta{font-size:12px;white-space:nowrap}
  .download-btns{flex-direction:column;gap:12px}
  .download-btns .btn{width:100%}
  .back-top{right:16px;bottom:24px;width:42px;height:42px}
}