* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: "Microsoft YaHei", Arial, sans-serif; background: #ffffff; min-height: 100vh; color: #333; line-height: 1.6; }

/* 头部导航 */
header { background: #fff; box-shadow: 0 1px 8px rgba(0,0,0,0.06); position: sticky; top: 0; z-index: 1000; }
.nav-container { max-width: 1200px; margin: 0 auto; padding: 12px 20px; display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 22px; font-weight: bold; color: #e53e3e; text-decoration: none; }
.logo span { color: #333; }
nav ul { display: flex; list-style: none; gap: 28px; }
nav a { text-decoration: none; color: #555; font-weight: 500; transition: color 0.3s; font-size: 15px; }
nav a:hover { color: #e53e3e; }
.nav-cta { background: #e53e3e; color: white; padding: 8px 20px; border-radius: 6px; text-decoration: none; font-weight: 600; font-size: 14px; transition: opacity 0.3s; }
.nav-cta:hover { opacity: 0.9; }

/* Hero 首屏 - 带底色 */
.hero { text-align: center; padding: 60px 20px 50px; color: #fff; background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%); }
.hero-text { max-width: 800px; margin: 0 auto; }
.hero h1 { font-size: 2.2em; margin-bottom: 16px; line-height: 1.3; }
.hero-subtitle { font-size: 1.1em; opacity: 0.9; margin-bottom: 8px; }
.hero-highlight { font-size: 1.2em; font-weight: bold; margin: 12px 0 20px; color: #fbbf24; }
.hero-tags { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 24px; justify-content: center; }
.hero-tags .tag { background: rgba(255,255,255,0.1); padding: 6px 14px; border-radius: 6px; font-size: 0.9em; border: 1px solid rgba(255,255,255,0.15); }
.hero-cta { display: inline-block; background: #e53e3e; color: #fff; padding: 12px 36px; border-radius: 8px; font-size: 1em; font-weight: bold; text-decoration: none; transition: transform 0.3s, box-shadow 0.3s; box-shadow: 0 4px 15px rgba(229,62,62,0.4); }
.hero-cta:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(229,62,62,0.5); }
.hero-image { flex: 1; min-width: 280px; text-align: center; }
.hero-image img { max-width: 100%; border-radius: 12px; }

/* 信任背书 */
.trust-bar { background: #f8f9fa; padding: 20px 0; border-bottom: 1px solid #eee; }
.trust-items { display: flex; justify-content: center; gap: 50px; flex-wrap: wrap; max-width: 1200px; margin: 0 auto; }
.trust-item { text-align: center; color: #333; }
.trust-num { display: block; font-size: 1.6em; font-weight: bold; color: #e53e3e; }
.trust-item span:last-child { font-size: 0.9em; color: #666; }

/* 产品介绍 */
.intro-section { padding: 0 20px; margin-top: 30px; }
.intro-box { max-width: 800px; margin: 0 auto; background: #f8f9fa; border-radius: 12px; padding: 28px 36px; text-align: center; border: 1px solid #eee; }
.intro-box h2 { color: #e53e3e; margin-bottom: 12px; font-size: 1.4em; }
.intro-box p { color: #555; font-size: 1.05em; line-height: 1.8; }
.intro-box strong { color: #333; }

.container { max-width: 1200px; margin: 0 auto; padding: 40px 20px; }

/* 区块标题 */
.section-title { text-align: center; font-size: 1.6em; color: #333; margin-bottom: 12px; }
.section-desc { text-align: center; color: #888; font-size: 0.95em; margin-bottom: 36px; }

/* 下载卡片 - 白底卡片网格 */
.download-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-bottom: 50px; }
.download-card { background: #fff; border-radius: 12px; padding: 24px; border: 1px solid #eee; transition: transform 0.3s, box-shadow 0.3s; }
.download-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(0,0,0,0.08); }
.card-header { display: flex; align-items: center; margin-bottom: 14px; }
.card-icon { min-width: 48px; height: 48px; border-radius: 10px; display: flex; align-items: center; justify-content: center; margin-right: 12px; font-size: 24px; color: white; overflow: visible; gap: 4px; }
.card-icon img { width: 42px; height: 42px; object-fit: contain; flex-shrink: 0; }
.card-icon img:only-child { width: 48px; height: 48px; }
.card-icon:not(:has(img)) { background: linear-gradient(135deg, #e53e3e, #c53030); width: 48px; }
.card-title h2 { font-size: 1.05em; color: #333; }
.card-desc { color: #666; margin-bottom: 14px; font-size: 0.9em; line-height: 1.7; }
.card-features { margin-bottom: 18px; }
.card-features li { list-style: none; padding: 5px 0; border-bottom: 1px dashed #f0f0f0; font-size: 0.85em; color: #555; }
.card-features li:before { content: "✓"; color: #e53e3e; margin-right: 8px; font-weight: bold; }
.download-btn { display: block; width: 100%; padding: 11px; background: #e53e3e; color: white; text-align: center; text-decoration: none; border-radius: 8px; font-weight: 600; font-size: 14px; transition: opacity 0.3s, transform 0.2s; border: none; cursor: pointer; }
.download-btn:hover { opacity: 0.9; transform: scale(1.02); }

/* 教程 */
.tutorial-section { margin-bottom: 50px; }
.tutorial-container { background: #fff; border-radius: 16px; padding: 40px; border: 1px solid #eee; max-width: 1000px; margin: 0 auto; }
.tutorial-tabs { display: flex; justify-content: center; gap: 12px; margin-bottom: 36px; flex-wrap: wrap; }
.tutorial-tab { padding: 10px 24px; background: #f5f5f5; border: 1px solid #eee; border-radius: 8px; cursor: pointer; font-size: 0.95em; font-weight: 500; color: #666; transition: all 0.3s; }
.tutorial-tab:hover { background: #eee; }
.tutorial-tab.active { background: #e53e3e; color: white; border-color: #e53e3e; }
.tutorial-content { display: none; }
.tutorial-content.active { display: block; animation: fadeIn 0.4s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
.tutorial-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: center; }
.tutorial-step { display: flex; align-items: flex-start; margin-bottom: 20px; padding: 16px; background: #f9f9f9; border-radius: 10px; transition: all 0.3s; }
.tutorial-step:hover { background: #f0f0f0; transform: translateX(4px); }
.step-number { width: 36px; height: 36px; background: #e53e3e; color: white; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 14px; flex-shrink: 0; font-size: 14px; }
.step-content h4 { color: #333; margin-bottom: 4px; font-size: 0.95em; }
.step-content p { color: #666; font-size: 0.85em; }
.tutorial-image { background: #f8f9fa; border-radius: 12px; padding: 36px; text-align: center; border: 1px solid #eee; }
.tutorial-image .icon { font-size: 80px; margin-bottom: 16px; }
.tutorial-image h3 { color: #e53e3e; font-size: 1.3em; margin-bottom: 8px; }
.tutorial-image p { color: #666; }
.tutorial-tips { margin-top: 30px; padding: 20px; background: #fffbeb; border-radius: 10px; border-left: 4px solid #f59e0b; }
.tutorial-tips h4 { color: #92400e; margin-bottom: 8px; }
.tutorial-tips ul { list-style: none; color: #92400e; }
.tutorial-tips li { padding: 4px 0; }
.tutorial-tips li:before { content: "💡"; margin-right: 8px; }

/* FAQ */
.faq-section { margin-bottom: 50px; }
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { background: #fff; border-radius: 10px; margin-bottom: 12px; border: 1px solid #eee; overflow: hidden; }
.faq-item summary { padding: 18px 20px; cursor: pointer; font-weight: bold; color: #333; font-size: 0.95em; }
.faq-item summary:hover { background: #f9f9f9; }
.faq-item p { padding: 0 20px 18px; color: #666; line-height: 1.8; font-size: 0.9em; }

/* 底部CTA */
.bottom-cta { background: linear-gradient(135deg, #1a1a2e, #16213e); padding: 50px 20px; color: white; }
.bottom-cta h2 { font-size: 1.6em; margin-bottom: 10px; }
.bottom-cta p { opacity: 0.85; margin-bottom: 24px; font-size: 1em; }
.cta-btn { display: inline-block; padding: 12px 32px; border-radius: 8px; font-weight: bold; font-size: 0.95em; text-decoration: none; margin: 0 6px; transition: all 0.3s; background: #e53e3e; color: #fff; }
.cta-btn:hover { transform: translateY(-2px); box-shadow: 0 4px 15px rgba(229,62,62,0.4); }
.cta-outline { background: transparent; color: white; border: 2px solid rgba(255,255,255,0.5); }
.cta-outline:hover { border-color: white; background: rgba(255,255,255,0.1); box-shadow: none; }

/* 页脚 */
footer { background: #1a1a2e; padding: 28px 20px; }
.footer-content { max-width: 1200px; margin: 0 auto; }
.footer-bottom { text-align: center; color: rgba(255,255,255,0.5); font-size: 13px; }
.footer-bottom p { margin: 3px 0; }

/* 悬浮客服 */
.customer-service { position: fixed; right: 20px; bottom: 100px; z-index: 999; }
.cs-btn { display: flex; align-items: center; gap: 8px; padding: 12px 20px; background: #e53e3e; color: white; text-decoration: none; border-radius: 30px; box-shadow: 0 4px 15px rgba(229,62,62,0.3); font-weight: 500; transition: all 0.3s; animation: pulse 2s infinite; }
.cs-btn:hover { transform: translateY(-3px); animation: none; }
@keyframes pulse { 0%, 100% { box-shadow: 0 4px 15px rgba(229,62,62,0.3); } 50% { box-shadow: 0 4px 25px rgba(229,62,62,0.5); } }
.cs-btn .icon { font-size: 20px; }

/* 返回顶部 */
.back-to-top { position: fixed; bottom: 30px; right: 30px; width: 46px; height: 46px; background: #e53e3e; color: white; border: none; border-radius: 50%; cursor: pointer; font-size: 18px; box-shadow: 0 4px 12px rgba(0,0,0,0.15); opacity: 0; visibility: hidden; transition: all 0.3s; }
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { transform: scale(1.1); }

.mobile-bottom-bar { display: none; }

/* 响应式 */
@media (max-width: 900px) {
    .tutorial-layout { grid-template-columns: 1fr; }
    .tutorial-image { order: -1; }
    .tutorial-container { padding: 24px 16px; }
    .download-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    .nav-container { flex-direction: column; gap: 10px; }
    nav ul { flex-wrap: wrap; justify-content: center; gap: 12px; }
    .nav-cta { display: none; }
    .hero { padding: 40px 20px 36px; margin: 16px; border-radius: 12px; flex-direction: column; text-align: center; }
    .hero-text { min-width: auto; padding: 0; }
    .hero h1 { font-size: 1.6em; }
    .hero-highlight { font-size: 1.1em; }
    .hero-tags { justify-content: center; }
    .hero-cta { padding: 11px 28px; font-size: 0.95em; }
    .hero-image { min-width: auto; }
    .trust-items { gap: 20px; }
    .trust-num { font-size: 1.3em; }
    .download-grid { grid-template-columns: 1fr; }
    .section-title { font-size: 1.3em; }
    .bottom-cta h2 { font-size: 1.2em; }
    .cta-btn { display: block; margin: 8px auto; max-width: 250px; text-align: center; }
    .customer-service { right: 15px; bottom: 80px; }
    .cs-btn { padding: 14px; border-radius: 50%; width: 50px; height: 50px; justify-content: center; }
    .cs-btn span:not(.icon) { display: none; }
    .back-to-top { right: 15px; bottom: 70px; width: 42px; height: 42px; }
    .intro-box { padding: 18px; }
    .mobile-bottom-bar { display: flex; position: fixed; bottom: 0; left: 0; right: 0; z-index: 1000; background: white; box-shadow: 0 -2px 10px rgba(0,0,0,0.1); padding: 10px 15px; gap: 10px; }
    .mobile-bar-btn { flex: 1; text-align: center; padding: 12px; border-radius: 8px; text-decoration: none; font-weight: bold; font-size: 15px; background: #f0f0f0; color: #333; }
    .mobile-bar-btn.primary { background: #e53e3e; color: white; }
    footer { padding-bottom: 80px; }
    .customer-service { bottom: 70px; }
}