:root {
            --bg-color: #000000;
            --text-primary: #f5f5f7;
            --text-secondary: #a1a1a6;
            --accent-color: #0071e3;
            --accent-hover: #0077ed;
            --card-bg: #111111;
            --border-color: rgba(255, 255, 255, 0.15);
            --font-family: 'Inter', 'SF Pro Display', 'Helvetica Neue', 'Helvetica', 'Arial', sans-serif;
        }
        * { margin: 0; padding: 0; box-sizing: border-box; }
        html { scroll-behavior: smooth; }
        body { font-family: var(--font-family); background-color: var(--bg-color); color: var(--text-primary); -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
        .background-container { position: fixed; top: 0; left: 0; width: 100vw; height: 100vh; z-index: -1; background-color: var(--bg-color); }
        .background-image { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background-size: cover; background-position: center; opacity: 0; filter: blur(8px) brightness(0.7); transform: scale(1.05); transition: opacity 1.5s cubic-bezier(0.4, 0, 0.2, 1), transform 1.5s cubic-bezier(0.4, 0, 0.2, 1); }
        .background-image.active { opacity: 0.5; transform: scale(1); }
        .main-header { position: sticky; top: 0; z-index: 100; background-color: rgba(0, 0, 0, 0.7); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px); border-bottom: 1px solid var(--border-color); }
        .nav-container { display: flex; justify-content: space-between; align-items: center; max-width: 1100px; margin: 0 auto; padding: 1rem 2rem; }
        .nav-title { font-size: 1.2rem; font-weight: 600; text-decoration: none; color: inherit; display: flex; align-items: center; }
        .nav-logo { height: 28px; margin-right: 12px; }
        .nav-title span { font-weight: 400; opacity: 0.7; }
        .nav-links a { color: var(--text-secondary); text-decoration: none; margin-left: 2rem; font-weight: 500; transition: color 0.3s ease; }
        .nav-links a:hover { color: var(--text-primary); }
        .nav-links a.active { color: var(--accent-color); font-weight: 600; }
        main { display: flex; flex-direction: column; align-items: center; }
        section { width: 100%; max-width: 1000px; padding: 6rem 2rem; text-align: center; }
        .fade-in-section { opacity: 0; transform: translateY(30px); transition: opacity 1s ease-out, transform 1s ease-out; }
        .fade-in-section.is-visible { opacity: 1; transform: translateY(0); }
        #hero { padding-top: 10rem; padding-bottom: 10rem; }
        .hero-title { font-size: 4.5rem; font-weight: 800; letter-spacing: -2px; line-height: 1.1; max-width: 800px; margin: 0 auto 1.5rem auto; background: -webkit-linear-gradient(45deg, #ffffff, #b0b0b0); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
        .hero-description { font-size: 1.3rem; color: var(--text-secondary); max-width: 650px; margin: 0 auto 2.5rem auto; line-height: 1.5; }
        .cta-button { display: inline-block; padding: 1rem 2.5rem; background: var(--accent-color); color: white; text-decoration: none; border-radius: 980px; font-size: 1.1rem; font-weight: 600; transition: background-color 0.3s, transform 0.2s; }
        .cta-button:hover { background-color: var(--accent-hover); transform: scale(1.05); }
        .features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.5rem; text-align: left; margin-top: 4rem; }
        .feature-card { background: var(--card-bg); border-radius: 20px; padding: 2rem; border: 1px solid var(--border-color); }
        .feature-card .icon { font-size: 1.8rem; color: var(--accent-color); margin-bottom: 1rem; }
        .feature-card h3 { font-size: 1.3rem; font-weight: 600; margin-bottom: 0.5rem; }
        .feature-card p { color: var(--text-secondary); font-size: 1rem; }
        footer { padding: 4rem 2rem; text-align: center; color: var(--text-secondary); font-size: 0.9rem; }
        @media (max-width: 768px) {
            .nav-container { padding: 1rem; }
            .nav-links { display: none; }
            section { padding: 4rem 1rem; }
            #hero { padding: 5rem 1rem; }
            .hero-title { font-size: 2.8rem; }
            .hero-description { font-size: 1.1rem; }
        }