/* ===== Reset & Base ===== */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
:root{
  --primary:#6366f1;
  --primary-dark:#4f46e5;
  --primary-light:#818cf8;
  --accent:#a855f7;
  --bg:#f8fafc;
  --bg-alt:#eef2f7;
  --surface:rgba(255,255,255,.72);
  --surface-solid:#fff;
  --text:#1e293b;
  --text-light:#64748b;
  --text-muted:#94a3b8;
  --border:rgba(148,163,184,.2);
  --shadow:0 4px 24px rgba(99,102,241,.08);
  --shadow-lg:0 12px 40px rgba(99,102,241,.15);
  --radius:14px;
  --radius-sm:8px;
  --max-w:1140px;
}
html{scroll-behavior:smooth;font-size:16px}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue","PingFang SC","Microsoft YaHei",sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.65;
  overflow-x:hidden;
}
a{color:var(--primary-dark);text-decoration:none;transition:color .2s}
a:hover{color:var(--accent)}
img{max-width:100%;display:block}
ul{list-style:none}

/* ===== Layout ===== */
.container{max-width:var(--max-w);margin:0 auto;padding:0 20px}
.section{padding:48px 0}
.section-sm{padding:32px 0}
.section-title{text-align:center;margin-bottom:32px}
.section-title h2{font-size:1.75rem;font-weight:700;letter-spacing:-.5px}
.section-title p{color:var(--text-light);margin-top:6px;font-size:.95rem}
.bg-alt{background:var(--bg-alt)}

/* ===== Header ===== */
.site-header{
  position:sticky;top:0;z-index:100;
  background:rgba(255,255,255,.82);
  backdrop-filter:blur(16px) saturate(1.8);
  -webkit-backdrop-filter:blur(16px) saturate(1.8);
  border-bottom:1px solid var(--border);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:60px}
.logo{display:flex;align-items:center;gap:8px;font-weight:700;font-size:1.15rem;color:var(--text)}
.logo img{width:28px;height:28px;border-radius:6px}
.logo span{background:linear-gradient(135deg,var(--primary),var(--accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.nav-links{display:flex;gap:6px;align-items:center}
.nav-links a{
  padding:7px 14px;border-radius:var(--radius-sm);font-size:.9rem;font-weight:500;color:var(--text-light);
  transition:all .2s;
}
.nav-links a:hover,.nav-links a.active{color:var(--primary-dark);background:rgba(99,102,241,.08)}
.nav-cta{
  background:linear-gradient(135deg,var(--primary),var(--primary-dark));
  color:#fff!important;padding:7px 18px;border-radius:var(--radius-sm);font-weight:600;font-size:.88rem;
}
.nav-cta:hover{box-shadow:0 4px 16px rgba(99,102,241,.4);transform:translateY(-1px);color:#fff}
.menu-toggle{display:none;font-size:1.5rem;background:none;border:none;cursor:pointer;color:var(--text)}

/* ===== Hero ===== */
.hero{
  position:relative;padding:56px 0 48px;text-align:center;
  background:linear-gradient(180deg,#eef2ff 0%,#f8fafc 100%);
  overflow:hidden;
}
.hero::before{
  content:'';position:absolute;top:-100px;left:50%;transform:translateX(-50%);
  width:600px;height:600px;background:radial-gradient(circle,rgba(99,102,241,.12) 0%,transparent 70%);
  pointer-events:none;
}
.hero h1{
  font-size:2.4rem;font-weight:800;letter-spacing:-1px;margin-bottom:12px;position:relative;
  background:linear-gradient(135deg,#4f46e5 0%,#7c3aed 50%,#a855f7 100%);
  -webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;
}
.hero .tagline{font-size:1.08rem;color:var(--text-light);max-width:640px;margin:0 auto 24px;position:relative}
.hero-badges{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;margin-bottom:28px;position:relative}
.badge{
  display:inline-flex;align-items:center;gap:4px;padding:4px 12px;border-radius:20px;
  font-size:.78rem;font-weight:500;background:rgba(99,102,241,.08);color:var(--primary-dark);
  border:1px solid rgba(99,102,241,.15);
}
.hero-cta{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;position:relative}

/* ===== Buttons ===== */
.btn{
  display:inline-flex;align-items:center;gap:8px;padding:11px 28px;border-radius:var(--radius-sm);
  font-weight:600;font-size:.92rem;transition:all .25s;cursor:pointer;border:none;
}
.btn-primary{background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff;box-shadow:0 4px 16px rgba(99,102,241,.3)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 28px rgba(99,102,241,.4);color:#fff}
.btn-outline{background:rgba(255,255,255,.8);color:var(--text);border:1.5px solid var(--border)}
.btn-outline:hover{border-color:var(--primary);color:var(--primary-dark);background:#fff}

/* ===== Cards & Grid ===== */
.grid{display:grid;gap:20px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}
.card{
  background:var(--surface-solid);border-radius:var(--radius);padding:24px;
  border:1px solid var(--border);box-shadow:var(--shadow);transition:all .3s;
}
.card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg);border-color:rgba(99,102,241,.3)}
.card-icon{
  width:44px;height:44px;border-radius:10px;display:flex;align-items:center;justify-content:center;
  font-size:1.3rem;margin-bottom:14px;
  background:linear-gradient(135deg,rgba(99,102,241,.12),rgba(168,85,247,.12));
}
.card h3{font-size:1.05rem;font-weight:700;margin-bottom:6px}
.card p{font-size:.88rem;color:var(--text-light);line-height:1.55}

/* ===== Feature List ===== */
.feature-list{display:flex;flex-direction:column;gap:0}
.feature-item{
  display:flex;gap:14px;padding:14px 0;border-bottom:1px solid var(--border);
}
.feature-item:last-child{border-bottom:none}
.feature-item .icon{
  flex-shrink:0;width:36px;height:36px;border-radius:8px;display:flex;align-items:center;justify-content:center;
  background:rgba(99,102,241,.08);color:var(--primary-dark);font-size:1rem;
}
.feature-item h4{font-size:.95rem;font-weight:600;margin-bottom:2px}
.feature-item p{font-size:.84rem;color:var(--text-light)}

/* ===== Preview / Mockup ===== */
.preview-box{
  border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow-lg);
  border:1px solid var(--border);background:#fff;
}
.taskbar-mock{
  position:relative;height:280px;
  background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);
  display:flex;align-items:center;justify-content:center;overflow:hidden;
}
.taskbar-mock .wallpaper-text{
  color:rgba(255,255,255,.7);font-size:1rem;font-weight:500;z-index:1;
}
.taskbar-bar{
  position:absolute;bottom:0;left:0;right:0;height:44px;
  display:flex;align-items:center;justify-content:center;gap:24px;
  backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);
  background:rgba(255,255,255,.15);
  border-top:1px solid rgba(255,255,255,.2);
}
.taskbar-bar .tb-icon{
  width:24px;height:24px;border-radius:4px;background:rgba(255,255,255,.3);
  display:flex;align-items:center;justify-content:center;font-size:.7rem;color:rgba(255,255,255,.9);
}
.taskbar-bar .tb-icon.active{background:rgba(255,255,255,.35);box-shadow:0 0 0 2px rgba(255,255,255,.3)}
.preview-label{
  position:absolute;top:12px;left:12px;
  background:rgba(0,0,0,.4);color:#fff;padding:4px 12px;border-radius:6px;font-size:.75rem;
  backdrop-filter:blur(10px);
}

/* ===== Comparison ===== */
.compare-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px}
.compare-item{
  border-radius:var(--radius);overflow:hidden;border:1px solid var(--border);box-shadow:var(--shadow);
}
.compare-item .compare-label{
  padding:8px 16px;font-size:.85rem;font-weight:600;text-align:center;
}
.compare-item .compare-label.before{background:#f1f5f9;color:var(--text-light)}
.compare-item .compare-label.after{background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff}
.compare-item .compare-img{
  height:200px;display:flex;align-items:flex-end;justify-content:center;position:relative;
}
.compare-item .compare-img .bar{
  width:100%;height:44px;display:flex;align-items:center;justify-content:center;gap:20px;
}
.compare-item .compare-img.opaque .bar{background:#0a0a1a}
.compare-item .compare-img.translucent .bar{
  background:rgba(255,255,255,.15);backdrop-filter:blur(20px);border-top:1px solid rgba(255,255,255,.2);
}
.compare-item .compare-img.opaque{background:linear-gradient(135deg,#3a3a5c 0%,#2a2a4c 100%)}
.compare-item .compare-img.translucent{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%)}
.compare-item .compare-img .bar .bi{width:22px;height:22px;border-radius:4px;background:rgba(255,255,255,.25)}

/* ===== Download Section ===== */
.download-cards{display:grid;grid-template-columns:1fr 1fr;gap:20px}
.dl-card{
  background:var(--surface-solid);border-radius:var(--radius);padding:28px;text-align:center;
  border:1px solid var(--border);box-shadow:var(--shadow);transition:all .3s;
}
.dl-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-lg)}
.dl-card .dl-icon{
  width:56px;height:56px;border-radius:14px;margin:0 auto 14px;
  display:flex;align-items:center;justify-content:center;font-size:1.5rem;color:#fff;
}
.dl-card.quark .dl-icon{background:linear-gradient(135deg,#3b82f6,#1d4ed8)}
.dl-card.baidu .dl-icon{background:linear-gradient(135deg,#06b6d4,#0891b2)}
.dl-card h3{font-size:1.1rem;font-weight:700;margin-bottom:4px}
.dl-card .dl-sub{font-size:.82rem;color:var(--text-muted);margin-bottom:16px}
.dl-card .btn{width:100%;justify-content:center}

/* ===== Steps ===== */
.steps{display:flex;flex-direction:column;gap:0;counter-reset:step}
.step{
  display:flex;gap:18px;padding:18px 0;border-bottom:1px solid var(--border);position:relative;
}
.step:last-child{border-bottom:none}
.step-num{
  flex-shrink:0;width:36px;height:36px;border-radius:50%;
  background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff;
  display:flex;align-items:center;justify-content:center;font-weight:700;font-size:.9rem;
}
.step-body h4{font-size:1rem;font-weight:600;margin-bottom:4px}
.step-body p{font-size:.88rem;color:var(--text-light)}
.step-body code{
  background:rgba(99,102,241,.08);padding:2px 8px;border-radius:4px;font-size:.85rem;
  color:var(--primary-dark);font-family:"Fira Code",Consolas,monospace;
}

/* ===== FAQ ===== */
.faq-item{
  border-bottom:1px solid var(--border);padding:0;
}
.faq-item summary{
  padding:16px 0;font-weight:600;font-size:.95rem;cursor:pointer;list-style:none;
  display:flex;align-items:center;justify-content:space-between;
}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{
  content:'\276F';font-size:.7rem;color:var(--text-muted);transition:transform .2s;
}
.faq-item[open] summary::after{transform:rotate(90deg)}
.faq-item .faq-a{padding:0 0 16px;font-size:.88rem;color:var(--text-light);line-height:1.7}

/* ===== Info Box ===== */
.info-box{
  background:rgba(99,102,241,.06);border-left:3px solid var(--primary);border-radius:0 var(--radius-sm) var(--radius-sm) 0;
  padding:14px 18px;font-size:.88rem;color:var(--text-light);margin:16px 0;
}
.info-box strong{color:var(--text)}
.info-box.warn{background:rgba(245,158,11,.08);border-left-color:#f59e0b}
.info-box.success{background:rgba(34,197,94,.08);border-left-color:#22c55e}

/* ===== Stats ===== */
.stats-row{display:flex;gap:32px;justify-content:center;flex-wrap:wrap}
.stat{text-align:center}
.stat .num{font-size:1.8rem;font-weight:800;background:linear-gradient(135deg,var(--primary),var(--accent));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.stat .label{font-size:.8rem;color:var(--text-muted);margin-top:2px}

/* ===== Page Header (inner pages) ===== */
.page-header{
  padding:40px 0 28px;text-align:center;
  background:linear-gradient(180deg,#eef2ff 0%,#f8fafc 100%);
}
.page-header h1{font-size:1.9rem;font-weight:800;margin-bottom:8px;color:var(--text)}
.page-header p{color:var(--text-light);font-size:.95rem}
.breadcrumb{font-size:.82rem;color:var(--text-muted);margin-top:10px}
.breadcrumb a{color:var(--text-muted)}
.breadcrumb a:hover{color:var(--primary-dark)}

/* ===== Footer ===== */
.site-footer{background:#1e293b;color:#cbd5e1;padding:40px 0 20px;margin-top:20px}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:32px;margin-bottom:28px}
.footer-brand .logo{color:#fff;margin-bottom:10px}
.footer-brand p{font-size:.84rem;color:#94a3b8;line-height:1.6}
.footer-col h4{font-size:.9rem;font-weight:600;margin-bottom:12px;color:#fff}
.footer-col a{display:block;font-size:.84rem;color:#94a3b8;padding:4px 0;transition:color .2s}
.footer-col a:hover{color:#fff}
.footer-bottom{
  border-top:1px solid rgba(148,163,184,.15);padding-top:16px;text-align:center;
  font-size:.8rem;color:#64748b;
}

/* ===== QR Code Breathing Effect ===== */
@keyframes qrBreath{
  0%,100%{box-shadow:0 0 0 0 rgba(99,102,241,.25),0 4px 16px rgba(99,102,241,.15);transform:scale(1)}
  50%{box-shadow:0 0 0 8px rgba(99,102,241,0),0 4px 24px rgba(99,102,241,.25);transform:scale(1.03)}
}
.qr-breath{
  animation:qrBreath 3s ease-in-out infinite;
  border-radius:12px;
  padding:6px;
  background:#fff;
}

/* ===== Modal ===== */
.modal-overlay{
  display:none;position:fixed;inset:0;z-index:9999;
  background:rgba(15,23,42,.55);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);
  align-items:center;justify-content:center;padding:20px;
}
.modal-overlay.show{display:flex}
.modal{
  background:#fff;border-radius:20px;max-width:520px;width:100%;padding:36px 32px 28px;
  box-shadow:0 24px 64px rgba(0,0,0,.18);position:relative;
  animation:modalIn .3s ease;
}
@keyframes modalIn{from{opacity:0;transform:translateY(20px) scale(.96)}to{opacity:1;transform:translateY(0) scale(1)}}
.modal-close{
  position:absolute;top:14px;right:18px;width:32px;height:32px;border-radius:50%;border:none;
  background:#f1f5f9;font-size:1.1rem;cursor:pointer;display:flex;align-items:center;justify-content:center;
  color:var(--text-light);transition:all .2s;
}
.modal-close:hover{background:#e2e8f0;color:var(--text)}
.modal-title{font-size:1.25rem;font-weight:700;text-align:center;margin-bottom:6px;color:var(--text)}
.modal-subtitle{font-size:.88rem;color:var(--text-light);text-align:center;margin-bottom:24px}
.modal-qr-wrap{display:flex;justify-content:center;margin-bottom:18px}
.modal-qr-wrap img{width:150px;height:150px;border-radius:10px}
.modal-features{margin-bottom:20px}
.modal-features li{
  display:flex;align-items:flex-start;gap:10px;padding:7px 0;font-size:.88rem;color:var(--text);
}
.modal-features li .ck{
  flex-shrink:0;width:20px;height:20px;border-radius:50%;
  background:linear-gradient(135deg,#22c55e,#16a34a);color:#fff;
  display:flex;align-items:center;justify-content:center;font-size:.7rem;margin-top:1px;
}
.modal-tip{
  background:linear-gradient(135deg,rgba(99,102,241,.06),rgba(168,85,247,.06));
  border:1px solid rgba(99,102,241,.12);border-radius:var(--radius-sm);
  padding:12px 16px;font-size:.84rem;color:var(--text-light);text-align:center;
}
.modal-tip strong{color:var(--primary-dark)}

/* ===== Responsive ===== */
@media(max-width:900px){
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .grid-3{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:700px){
  .nav-links{display:none;position:absolute;top:60px;left:0;right:0;flex-direction:column;background:#fff;padding:12px;box-shadow:var(--shadow-lg);gap:2px}
  .nav-links.show{display:flex}
  .nav-links a{width:100%;padding:10px 14px}
  .menu-toggle{display:block}
  .hero h1{font-size:1.7rem}
  .hero .tagline{font-size:.95rem}
  .grid-2,.grid-3,.grid-4{grid-template-columns:1fr}
  .compare-grid{grid-template-columns:1fr}
  .download-cards{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr}
  .section{padding:32px 0}
  .section-title h2{font-size:1.4rem}
}