/* Quickq q9 - Convertio.co style - 简约现代 */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #eff6ff;
  --accent: #f59e0b;
  --bg: #ffffff;
  --bg-secondary: #f8fafc;
  --text: #1e293b;
  --text-light: #64748b;
  --border: #e2e8f0;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.05);
  --shadow-lg: 0 4px 16px rgba(0,0,0,0.1);
  --max-w: 1200px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; color: var(--text); background: var(--bg); line-height: 1.6; font-size: 16px; }

/* Header */
header { position: sticky; top: 0; z-index: 100; background: rgba(255,255,255,0.92); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); }
.header-inner { max-width: var(--max-w); margin: 0 auto; padding: 0 24px; display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { font-size: 22px; font-weight: 700; color: var(--primary); text-decoration: none; letter-spacing: -0.5px; }
.logo span { color: var(--text); }
nav { display: flex; gap: 4px; align-items: center; }
nav a { padding: 8px 16px; color: var(--text-light); text-decoration: none; font-size: 15px; border-radius: 8px; transition: all 0.2s; }
nav a:hover, nav a.active { color: var(--primary); background: var(--primary-light); }
.btn-primary { background: var(--primary); color: #fff !important; padding: 8px 20px !important; border-radius: 8px !important; font-weight: 600 !important; }
.btn-primary:hover { background: var(--primary-dark) !important; }

/* Hero */
.hero { text-align: center; padding: 80px 24px 64px; background: linear-gradient(180deg, #eff6ff 0%, var(--bg) 100%); }
.hero h1 { font-size: 44px; font-weight: 800; color: var(--text); margin-bottom: 16px; letter-spacing: -1px; line-height: 1.15; }
.hero p { font-size: 18px; color: var(--text-light); max-width: 560px; margin: 0 auto 36px; }
.hero-tags { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.tag { background: #fff; border: 1px solid var(--border); padding: 6px 16px; border-radius: 20px; font-size: 14px; color: var(--text-light); }

/* Sections */
.section { padding: 64px 24px; max-width: var(--max-w); margin: 0 auto; }
.section-title { text-align: center; font-size: 32px; font-weight: 700; color: var(--text); margin-bottom: 8px; }
.section-sub { text-align: center; color: var(--text-light); font-size: 16px; margin-bottom: 48px; }

/* Feature Grid */
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; }
.feature-card { background: #fff; border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; transition: all 0.2s; }
.feature-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-2px); border-color: var(--primary); }
.feature-icon { width: 48px; height: 48px; background: var(--primary-light); border-radius: 10px; display: flex; align-items: center; justify-content: center; margin-bottom: 16px; font-size: 22px; }
.feature-card h3 { font-size: 18px; font-weight: 600; margin-bottom: 8px; color: var(--text); }
.feature-card p { color: var(--text-light); font-size: 14px; }

/* Download Section */
.download-section { background: linear-gradient(135deg, var(--primary) 0%, #3b82f6 100%); color: #fff; text-align: center; padding: 72px 24px; border-radius: 24px; margin: 0 24px 64px; }
.download-section h2 { font-size: 36px; font-weight: 700; margin-bottom: 12px; }
.download-section p { opacity: 0.85; font-size: 17px; margin-bottom: 36px; }
.platform-btns { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.platform-btn { background: #fff; color: var(--primary); padding: 14px 32px; border-radius: 10px; font-weight: 700; font-size: 16px; text-decoration: none; display: inline-flex; align-items: center; gap: 8px; transition: transform 0.15s; box-shadow: 0 4px 12px rgba(0,0,0,0.15); }
.platform-btn:hover { transform: scale(1.05); }
.platform-btn .icon { font-size: 20px; }

/* Steps */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 32px; margin-top: 48px; }
.step { text-align: center; }
.step-num { width: 48px; height: 48px; background: var(--primary); color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 20px; font-weight: 700; margin: 0 auto 12px; }
.step h3 { font-size: 17px; font-weight: 600; margin-bottom: 6px; }
.step p { color: var(--text-light); font-size: 14px; }

/* Compare Table */
.compare-table { width: 100%; border-collapse: collapse; background: #fff; border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.compare-table th { background: var(--primary-light); padding: 16px; text-align: left; font-weight: 600; font-size: 15px; color: var(--text); }
.compare-table td { padding: 14px 16px; border-top: 1px solid var(--border); font-size: 14px; color: var(--text-light); }
.compare-table tr:hover td { background: #f8fafc; }
.compare-table .check { color: #22c55e; font-weight: 700; }

/* FAQ */
.faq-list { max-width: 680px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid var(--border); }
.faq-q { width: 100%; background: none; border: none; padding: 20px 0; font-size: 16px; font-weight: 600; color: var(--text); text-align: left; cursor: pointer; display: flex; justify-content: space-between; align-items: center; }
.faq-q::after { content: '+'; font-size: 22px; color: var(--primary); transition: transform 0.2s; }
.faq-item.open .faq-q::after { transform: rotate(45deg); }
.faq-a { max-height: 0; overflow: hidden; transition: max-height 0.3s ease; color: var(--text-light); font-size: 15px; line-height: 1.7; padding-bottom: 20px; }
.faq-item.open .faq-a { max-height: 300px; }

/* Footer */
footer { background: #0f172a; color: #94a3b8; padding: 48px 24px 32px; margin-top: 80px; }
.footer-inner { max-width: var(--max-w); margin: 0 auto; display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 40px; }
.footer-col h4 { color: #fff; font-size: 15px; margin-bottom: 16px; }
.footer-col a { display: block; color: #64748b; text-decoration: none; font-size: 14px; margin-bottom: 10px; transition: color 0.2s; }
.footer-col a:hover { color: #fff; }
.footer-bottom { max-width: var(--max-w); margin: 40px auto 0; padding-top: 24px; border-top: 1px solid #1e293b; text-align: center; font-size: 13px; }


/* Friend Links */
.friend-links { background: var(--bg-secondary); border-top: 1px solid var(--border); padding: 32px 24px; margin-top: 64px; }
.friend-links-inner { max-width: var(--max-w); margin: 0 auto; }
.friend-links-title { font-size: 14px; font-weight: 600; color: var(--text-light); margin-bottom: 12px; }
.friend-links-list { display: flex; flex-wrap: wrap; gap: 12px 20px; }
.friend-links-list a { color: var(--text-light); text-decoration: none; font-size: 14px; transition: color 0.2s; }
.friend-links-list a:hover { color: var(--primary); }
/* Mobile */
@media (max-width: 768px) {
  nav { display: none; }
  .header-inner { position: relative; }
  .mobile-menu-btn { display: block; background: none; border: none; font-size: 24px; cursor: pointer; color: var(--text); }
  .hero h1 { font-size: 30px; }
  .download-section { margin: 0 0 40px; }
  .platform-btns { flex-direction: column; align-items: center; }
}

/* Utility */
.text-center { text-align: center; }
.mt-4 { margin-top: 16px; }
.mt-8 { margin-top: 32px; }
/* --- q3q9 外置语义类 (整改生成) --- */
.text-muted-sm { color:var(--text-light);font-size:14px;margin-bottom:12px; }
.platform-btn.download-btn { background:var(--primary);color:#fff; }
.bg-secondary { background:var(--bg-secondary); }
.text-muted-mb32 { color:var(--text-light);margin-bottom:32px; }
.container-720-center { margin:0 auto;max-width:720px;text-align:center; }
.icon-box { font-size:36px;height:80px;margin:0 auto 24px;width:80px; }
.title-md { font-size:28px;font-weight:700;margin-bottom:8px; }
.platform-btn.download-btn-lg { background:var(--primary);color:#fff;font-size:18px;padding:16px 40px; }
.text-muted-xs-mt16 { color:var(--text-light);font-size:13px;margin-top:16px; }
.center-mb16 { margin:0 auto 16px; }
.mb-16 { margin-bottom:16px; }
.text-muted { color:var(--text-light); }
.title-sm { font-size:20px;margin-bottom:12px; }
.mb-32 { margin-bottom:32px; }
.text-primary-mb12 { color:var(--primary);margin-bottom:12px; }
.text-muted-mb24-lh { color:var(--text-light);line-height:1.8;margin-bottom:24px; }
.text-primary { color:var(--primary); }
.title-md-sm { font-size:28px;font-weight:700;margin-bottom:4px; }
.text-muted-xs-mb24 { color:var(--text-light);font-size:13px;margin-bottom:24px; }
.mt-24-left { margin-top:24px;text-align:left; }
.text-muted-mb8 { color:var(--text-light);margin-bottom:8px; }
.container-720-left { margin:0 auto;max-width:720px;text-align:left; }
.container-600-center { margin:0 auto;max-width:600px;text-align:center; }
.box-bordered { border:2px solid var(--border);text-align:center; }
.text-muted-14-mb8 { color:var(--text-light);font-size:14px;margin-bottom:8px; }
.link-card { background:var(--primary-light);border-radius:8px;color:var(--primary);display:block;font-weight:600;padding:12px;text-decoration:none; }
.text-slate-mb12 { color:#94a3b8;font-size:14px;margin-bottom:12px; }
.fw-normal-14 { font-size:14px;font-weight:400; }
.text-muted-16-lh-mb32 { color:var(--text-light);font-size:16px;line-height:1.8;margin-bottom:32px; }
.text-muted-mb16 { color:var(--text-light);margin-bottom:16px; }
.grid-cards-900 { display:grid;gap:24px;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));margin:0 auto;max-width:900px; }
.box-primary { border:2px solid var(--primary);text-align:center; }
.text-primary-14-mb8 { color:var(--primary);font-size:14px;margin-bottom:8px; }
.link-card-primary { background:var(--primary);border-radius:8px;color:#fff;display:block;font-weight:600;padding:12px;text-decoration:none; }
.grid-cards-300 { display:grid;gap:24px;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));margin-top:32px; }
.bg-secondary-pad { background:var(--bg-secondary);padding:64px 24px; }
.grid-gap24 { display:grid;gap:24px; }
.mt-40 { margin-top:40px; }
.container-800-left { margin:0 auto;max-width:800px;text-align:left; }
.text-muted-mb24 { color:var(--text-light);margin-bottom:24px; }
.text-muted-lh { color:var(--text-light);line-height:1.8; }
.container-600 { margin:0 auto;max-width:600px; }