/* Reset & Base */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif; background: #0a0f1a; color: #e0e6ed; line-height: 1.6; min-height: 100vh; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

/* Sound Wave Theme Variables */
:root {
    --sw-cyan: #00e5ff;
    --sw-blue: #2979ff;
    --sw-purple: #d500f9;
    --sw-dark: #050810;
    --sw-card: rgba(15, 22, 38, 0.8);
}

/* Navigation */
.navbar { display: flex; justify-content: space-between; align-items: center; padding: 20px 5%; background: rgba(5, 8, 16, 0.95); border-bottom: 1px solid rgba(0, 229, 255, 0.2); position: sticky; top: 0; z-index: 100; backdrop-filter: blur(2px); }
.nav-logo { font-size: 24px; font-weight: bold; color: var(--sw-cyan); display: flex; align-items: center; gap: 10px; text-shadow: 0 0 10px rgba(0, 229, 255, 0.5); }
.nav-links { display: flex; gap: 30px; align-items: center; font-weight: 500; }
.nav-links a { font-size: 16px; transition: all 0.3s; color: #a0aec0; }
.nav-links a:hover { color: var(--sw-cyan); text-shadow: 0 0 8px var(--sw-cyan); }
.btn-download-nav { padding: 8px 25px; background: linear-gradient(90deg, var(--sw-blue), var(--sw-cyan)); border-radius: 25px; color: #fff !important; font-weight: bold; box-shadow: 0 4px 15px rgba(0, 229, 255, 0.3); transition: transform 0.3s, box-shadow 0.3s; }
.btn-download-nav:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(0, 229, 255, 0.5); }

/* Hero Section */
.hero { position: relative; padding: 100px 5% 80px; text-align: center; overflow: hidden; min-height: 85vh; display: flex; flex-direction: column; justify-content: center; align-items: center; background: radial-gradient(circle at center, #111a2e 0%, var(--sw-dark) 100%); }
.hero-content { z-index: 2; max-width: 900px; margin: 0 auto; position: relative; }
.hero h1 { font-size: 48px; margin-bottom: 20px; color: #fff; text-shadow: 0 2px 10px rgba(0,0,0,0.5); }
.hero h1 span { background: linear-gradient(90deg, var(--sw-cyan), var(--sw-purple)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.hero p { font-size: 20px; margin-bottom: 30px; color: #a0aec0; }

/* Sound Wave Animation */
.equalizer { display: flex; gap: 6px; justify-content: center; align-items: flex-end; height: 80px; margin: 0 auto 40px; }
.bar { width: 10px; background: linear-gradient(to top, var(--sw-blue), var(--sw-cyan)); border-radius: 5px; animation: bounce 1s infinite ease-in-out alternate; box-shadow: 0 0 10px var(--sw-cyan); }
.bar:nth-child(1) { animation-delay: 0.1s; height: 30px; }
.bar:nth-child(2) { animation-delay: 0.4s; height: 60px; }
.bar:nth-child(3) { animation-delay: 0.2s; height: 45px; }
.bar:nth-child(4) { animation-delay: 0.6s; height: 80px; }
.bar:nth-child(5) { animation-delay: 0.3s; height: 50px; }
.bar:nth-child(6) { animation-delay: 0.5s; height: 70px; }
.bar:nth-child(7) { animation-delay: 0.1s; height: 40px; }
@keyframes bounce { 0% { transform: scaleY(0.3); opacity: 0.5; } 100% { transform: scaleY(1); opacity: 1; } }

.hero-buttons { display: flex; gap: 20px; justify-content: center; margin-bottom: 50px; flex-wrap: wrap; }
.btn-sw { padding: 15px 40px; font-size: 18px; font-weight: bold; border-radius: 30px; color: #fff; background: rgba(41, 121, 255, 0.1); border: 1px solid var(--sw-blue); box-shadow: 0 0 15px rgba(41, 121, 255, 0.2); transition: all 0.3s; }
.btn-sw:hover { background: rgba(41, 121, 255, 0.3); box-shadow: 0 0 25px rgba(41, 121, 255, 0.5); transform: translateY(-2px); }
.btn-pc { background: linear-gradient(90deg, var(--sw-blue), var(--sw-purple)); border: none; box-shadow: 0 5px 20px rgba(213, 0, 249, 0.4); }
.btn-pc:hover { background: linear-gradient(90deg, var(--sw-cyan), var(--sw-blue)); box-shadow: 0 5px 25px rgba(0, 229, 255, 0.5); }

.hero-images { display: flex; justify-content: center; gap: 20px; margin-top: 20px; z-index: 1; align-items: flex-end; }
.hero-images img { max-width: 30%; border-radius: 12px; box-shadow: 0 20px 40px rgba(0,0,0,0.6); border: 1px solid rgba(0, 229, 255, 0.2); transition: transform 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275); }
.hero-images img:hover { transform: translateY(-15px) scale(1.02); border-color: var(--sw-cyan); box-shadow: 0 20px 50px rgba(0, 229, 255, 0.3); }

/* Features Section */
.features { padding: 100px 5%; background: var(--sw-dark); position: relative; }
.section-title { text-align: center; font-size: 36px; margin-bottom: 60px; color: #fff; }
.section-title span { color: var(--sw-cyan); }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; max-width: 1200px; margin: 0 auto; }
.feature-card { background: var(--sw-card); padding: 40px 30px; border-radius: 16px; border: 1px solid rgba(255,255,255,0.05); transition: all 0.3s; text-align: center; }
.feature-card:hover { transform: translateY(-10px); background: rgba(20, 30, 50, 0.9); border-color: rgba(0, 229, 255, 0.3); box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5), 0 0 20px rgba(0, 229, 255, 0.1) inset; }
.feature-card h3 { font-size: 22px; margin-bottom: 15px; color: #fff; }
.feature-card p { color: #8f9ba8; font-size: 15px; line-height: 1.7; }

/* Blog Section */
.blog { padding: 100px 5%; background: #f8fafc; color: #1a202c; }
.blog .section-title { color: #1a202c; }
.blog .section-title span { color: var(--sw-blue); }
.blog-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 40px; max-width: 1200px; margin: 0 auto; }
.blog-card { background: #fff; border-radius: 16px; overflow: hidden; box-shadow: 0 10px 30px rgba(0,0,0,0.05); transition: transform 0.3s, box-shadow 0.3s; }
.blog-card:hover { transform: translateY(-8px); box-shadow: 0 15px 40px rgba(0, 229, 255, 0.15); }
.blog-card img { width: 100%; height: 260px; object-fit: cover; }
.blog-content { padding: 30px; }
.blog-date { display: inline-block; color: var(--sw-blue); font-weight: bold; font-size: 14px; margin-bottom: 10px; }
.blog-content h3 { font-size: 22px; margin-bottom: 15px; color: #2d3748; }
.blog-content p { color: #718096; margin-bottom: 0; }
.btn-more { display: block; width: 200px; margin: 50px auto 0; text-align: center; padding: 12px; border-radius: 25px; background: #fff; color: var(--sw-blue); font-weight: bold; border: 2px solid var(--sw-blue); transition: all 0.3s; }
.btn-more:hover { background: var(--sw-blue); color: #fff; box-shadow: 0 5px 15px rgba(41, 121, 255, 0.3); }

/* FAQ Section */
.faq { padding: 100px 5%; max-width: 900px; margin: 0 auto; background: var(--sw-dark); }
.faq-item { background: var(--sw-card); margin-bottom: 20px; border-radius: 12px; border: 1px solid rgba(255,255,255,0.05); padding: 25px 30px; transition: all 0.3s; }
.faq-item:hover { border-color: rgba(0, 229, 255, 0.3); background: rgba(20, 30, 50, 0.9); }
.faq-question { font-size: 18px; font-weight: bold; color: #fff; margin-bottom: 12px; display: flex; align-items: center; gap: 10px; }
.faq-question::before { content: 'Q.'; color: var(--sw-cyan); font-size: 22px; }
.faq-answer { color: #8f9ba8; line-height: 1.8; font-size: 15px; padding-left: 32px; }

/* Footer */
.footer { background: #03050a; padding: 80px 5% 30px; border-top: 1px solid rgba(255,255,255,0.05); }
.footer-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 40px; max-width: 1200px; margin: 0 auto 50px; }
.footer-col h4 { font-size: 18px; color: #fff; margin-bottom: 25px; font-weight: bold; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { color: #718096; transition: color 0.3s; }
.footer-col ul li a:hover { color: var(--sw-cyan); }
.footer-bottom { text-align: center; padding-top: 30px; border-top: 1px solid rgba(255,255,255,0.05); color: #4a5568; font-size: 14px; }

/* Page specific headers */
.page-header { padding: 120px 5% 80px; text-align: center; background: radial-gradient(circle at top, #111a2e 0%, var(--sw-dark) 100%); border-bottom: 1px solid rgba(0, 229, 255, 0.1); }
.page-header h1 { font-size: 42px; color: #fff; margin-bottom: 20px; }
.page-header h1 span { color: var(--sw-cyan); }
.page-header p { color: #a0aec0; font-size: 18px; max-width: 600px; margin: 0 auto; }

/* Download Page Grid */
.download-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 30px; max-width: 1100px; margin: 60px auto; padding: 0 5%; }
.download-card { background: var(--sw-card); border: 1px solid rgba(255,255,255,0.05); border-radius: 16px; padding: 40px 30px; text-align: center; transition: all 0.3s; }
.download-card:hover { transform: translateY(-10px); border-color: var(--sw-cyan); box-shadow: 0 15px 30px rgba(0,0,0,0.5); background: rgba(20, 30, 50, 0.9); }
.download-card h3 { color: #fff; font-size: 24px; margin-bottom: 15px; }
.download-card p { color: #8f9ba8; margin-bottom: 30px; font-size: 15px; }
.download-card .btn-sw { display: inline-block; padding: 10px 30px; font-size: 16px; }

/* === perf: reduce motion & lower GPU cost === */
.feature-card,
.blog-card,
.hero-content,
.glass-panel,
.pearl-card {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
}
.navbar {
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
}
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation: none !important;
        transition: none !important;
        scroll-behavior: auto !important;
    }
}

/* perf: limit decorative infinite layers on mid/low-end devices */
@media (max-width: 768px) {
    .bubble:nth-child(n+3),
    .tiny-plane:nth-child(n+3),
    .bg-shard:nth-child(n+4),
    .orb:nth-child(n+2) {
        display: none !important;
    }
}