/* === Reset & Base === */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    color: #333; background: #fff; line-height: 1.6;
}
a { text-decoration: none; color: inherit; transition: color .2s; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

/* === Container === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* === Navigation === */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: rgba(255,255,255,.97); border-bottom: 1px solid #e8ecf1;
    backdrop-filter: blur(10px); height: 64px;
}
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 100%; }
.nav-logo { font-size: 1.5rem; font-weight: 700; color: #1a73e8; letter-spacing: -0.5px; }
.nav-logo span { color: #0d47a1; }
.nav-links { display: flex; gap: 32px; }
.nav-links a {
    font-size: .95rem; color: #555; font-weight: 500; padding: 6px 0;
    border-bottom: 2px solid transparent; transition: all .2s;
}
.nav-links a:hover, .nav-links a.active { color: #1a73e8; border-bottom-color: #1a73e8; }
.nav-cta {
    display: inline-block; padding: 8px 22px; background: #1a73e8; color: #fff;
    border-radius: 6px; font-size: .9rem; font-weight: 500; transition: background .2s;
}
.nav-cta:hover { background: #1557b0; color: #fff; }

/* === Hero === */
.hero {
    padding: 160px 0 100px; text-align: center;
    background: linear-gradient(135deg, #0d1b3e 0%, #1a3a6b 40%, #1a73e8 100%);
    color: #fff; position: relative; overflow: hidden;
}
.hero::before {
    content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
    background: radial-gradient(circle at 30% 50%, rgba(79,195,247,.12) 0%, transparent 50%),
                radial-gradient(circle at 70% 80%, rgba(26,115,232,.1) 0%, transparent 40%);
    animation: heroGlow 8s ease-in-out infinite alternate;
}
@keyframes heroGlow { 0%{transform:translate(0,0)} 100%{transform:translate(-2%,2%)} }
.hero-content { position: relative; z-index: 1; }
.hero h1 { font-size: 3.2rem; font-weight: 800; margin-bottom: 20px; letter-spacing: -1px; }
.hero .subtitle { font-size: 1.25rem; color: rgba(255,255,255,.85); margin-bottom: 40px; max-width: 600px; margin-left: auto; margin-right: auto; }
.hero-buttons { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.btn-primary {
    display: inline-block; padding: 14px 40px; background: #4fc3f7; color: #0d1b3e;
    border-radius: 8px; font-size: 1.1rem; font-weight: 700; transition: all .25s;
    box-shadow: 0 4px 20px rgba(79,195,247,.35);
}
.btn-primary:hover { background: #fff; color: #0d1b3e; transform: translateY(-2px); box-shadow: 0 6px 24px rgba(79,195,247,.45); }
.btn-secondary {
    display: inline-block; padding: 14px 40px; border: 2px solid rgba(255,255,255,.5);
    color: #fff; border-radius: 8px; font-size: 1.1rem; font-weight: 600; transition: all .25s;
}
.btn-secondary:hover { border-color: #fff; background: rgba(255,255,255,.1); color: #fff; }

/* === Section Common === */
.section { padding: 80px 0; }
.section-alt { background: #f5f7fa; }
.section-title { text-align: center; margin-bottom: 56px; }
.section-title h2 { font-size: 2.2rem; font-weight: 700; color: #1a1a2e; margin-bottom: 12px; }
.section-title p { font-size: 1.05rem; color: #666; max-width: 560px; margin: 0 auto; }

/* === Features Grid === */
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.feature-card {
    background: #fff; border-radius: 12px; padding: 36px 28px; text-align: center;
    border: 1px solid #e8ecf1; transition: all .3s;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 12px 36px rgba(0,0,0,.08); border-color: #1a73e8; }
.feature-icon {
    width: 64px; height: 64px; margin: 0 auto 20px; border-radius: 16px;
    background: linear-gradient(135deg, #e3f2fd, #bbdefb); display: flex; align-items: center; justify-content: center;
    font-size: 1.8rem;
}
.feature-card h3 { font-size: 1.15rem; font-weight: 600; margin-bottom: 10px; color: #1a1a2e; }
.feature-card p { font-size: .92rem; color: #666; line-height: 1.6; }

/* === Product Showcase === */
.showcase { display: flex; align-items: center; gap: 60px; }
.showcase-text { flex: 1; }
.showcase-text h3 { font-size: 1.8rem; font-weight: 700; margin-bottom: 16px; color: #1a1a2e; }
.showcase-text p { font-size: 1rem; color: #555; margin-bottom: 20px; line-height: 1.8; }
.showcase-steps { display: flex; flex-direction: column; gap: 16px; }
.showcase-step {
    display: flex; align-items: center; gap: 14px; padding: 14px 18px;
    background: #f5f7fa; border-radius: 10px; transition: background .2s;
}
.showcase-step:hover { background: #e3f2fd; }
.step-num {
    width: 32px; height: 32px; border-radius: 50%; background: #1a73e8; color: #fff;
    display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: .9rem; flex-shrink: 0;
}
.showcase-visual {
    flex: 1; background: linear-gradient(135deg, #e3f2fd, #bbdefb);
    border-radius: 16px; padding: 40px; text-align: center; min-height: 320px;
    display: flex; align-items: center; justify-content: center;
}
.showcase-visual .phone-mock {
    width: 200px; height: 360px; background: #fff; border-radius: 28px;
    box-shadow: 0 20px 60px rgba(0,0,0,.12); padding: 12px; position: relative;
}
.phone-screen {
    width: 100%; height: 100%; background: linear-gradient(180deg, #1a73e8, #0d47a1);
    border-radius: 20px; display: flex; flex-direction: column; align-items: center;
    justify-content: center; color: #fff;
}
.phone-screen .connect-btn {
    width: 80px; height: 80px; border-radius: 50%; background: rgba(255,255,255,.2);
    border: 3px solid #4fc3f7; display: flex; align-items: center; justify-content: center;
    font-size: 2rem; margin-bottom: 16px;
}
.phone-screen .status { font-size: .85rem; opacity: .9; }

/* === Platforms === */
.platforms-grid { display: flex; justify-content: center; gap: 40px; flex-wrap: wrap; }
.platform-item {
    text-align: center; padding: 28px 36px; background: #fff; border-radius: 12px;
    border: 1px solid #e8ecf1; transition: all .3s; min-width: 160px;
}
.platform-item:hover { transform: translateY(-4px); box-shadow: 0 8px 28px rgba(0,0,0,.08); border-color: #1a73e8; }
.platform-icon { font-size: 2.8rem; margin-bottom: 12px; }
.platform-item h4 { font-size: 1rem; font-weight: 600; color: #1a1a2e; margin-bottom: 4px; }
.platform-item p { font-size: .82rem; color: #999; }
.platform-note { text-align: center; margin-top: 32px; font-size: 1rem; color: #666; }
.platform-note strong { color: #1a73e8; }

/* === Trust === */
.trust-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.trust-card {
    text-align: center; padding: 40px 28px; background: #fff; border-radius: 12px;
    border: 1px solid #e8ecf1;
}
.trust-num { font-size: 2.8rem; font-weight: 800; color: #1a73e8; margin-bottom: 8px; }
.trust-card h4 { font-size: 1.05rem; font-weight: 600; color: #1a1a2e; margin-bottom: 8px; }
.trust-card p { font-size: .9rem; color: #666; }

/* === CTA Section === */
.cta-section {
    padding: 80px 0; text-align: center;
    background: linear-gradient(135deg, #0d1b3e, #1a3a6b);
    color: #fff;
}
.cta-section h2 { font-size: 2.2rem; font-weight: 700; margin-bottom: 16px; }
.cta-section p { font-size: 1.1rem; color: rgba(255,255,255,.8); margin-bottom: 36px; }

/* === FAQ === */
.faq-list { max-width: 800px; margin: 0 auto; display: flex; flex-direction: column; gap: 20px; }
.faq-item { background: #fff; border-radius: 12px; border: 1px solid #e8ecf1; overflow: hidden; }
.faq-question {
    padding: 20px 24px; font-size: 1.05rem; font-weight: 600; color: #1a1a2e;
    border-bottom: 1px solid #e8ecf1; background: #fafbfc;
}
.faq-answer { padding: 20px 24px; }
.faq-step {
    display: flex; gap: 12px; margin-bottom: 12px; align-items: flex-start;
}
.faq-step:last-child { margin-bottom: 0; }
.faq-step-num {
    width: 24px; height: 24px; border-radius: 50%; background: #e3f2fd; color: #1a73e8;
    display: flex; align-items: center; justify-content: center; font-size: .75rem;
    font-weight: 700; flex-shrink: 0; margin-top: 2px;
}
.faq-step p { font-size: .92rem; color: #555; line-height: 1.7; }

/* === Footer === */
.footer {
    background: #0d1b3e; color: rgba(255,255,255,.7); padding: 48px 0 24px;
}
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand h3 { font-size: 1.3rem; color: #fff; margin-bottom: 12px; }
.footer-brand p { font-size: .88rem; line-height: 1.7; }
.footer-col h4 { font-size: .95rem; color: #fff; margin-bottom: 16px; font-weight: 600; }
.footer-col a { display: block; font-size: .88rem; color: rgba(255,255,255,.6); margin-bottom: 10px; transition: color .2s; }
.footer-col a:hover { color: #4fc3f7; }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.1); padding-top: 20px;
    display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px;
    font-size: .82rem;
}
.footer-official { color: #4fc3f7; font-weight: 500; }

/* === Page Header (for inner pages) === */
.page-header {
    padding: 120px 0 60px; text-align: center;
    background: linear-gradient(135deg, #0d1b3e 0%, #1a3a6b 60%, #1a73e8 100%);
    color: #fff;
}
.page-header h1 { font-size: 2.6rem; font-weight: 800; margin-bottom: 12px; }
.page-header p { font-size: 1.1rem; color: rgba(255,255,255,.8); max-width: 560px; margin: 0 auto; }

/* === Download Page === */
.download-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; max-width: 800px; margin: 0 auto; }
.download-card {
    display: flex; align-items: center; gap: 20px; padding: 28px; background: #fff;
    border-radius: 12px; border: 1px solid #e8ecf1; transition: all .3s;
}
.download-card:hover { transform: translateY(-4px); box-shadow: 0 8px 28px rgba(0,0,0,.08); border-color: #1a73e8; }
.download-card-icon { font-size: 2.4rem; flex-shrink: 0; }
.download-card-info h3 { font-size: 1.1rem; font-weight: 600; color: #1a1a2e; margin-bottom: 4px; }
.download-card-info p { font-size: .85rem; color: #999; margin-bottom: 10px; }
.download-btn {
    display: inline-block; padding: 8px 24px; background: #1a73e8; color: #fff;
    border-radius: 6px; font-size: .88rem; font-weight: 500; transition: background .2s;
}
.download-btn:hover { background: #1557b0; color: #fff; }

/* === Product Page === */
.product-features { display: flex; flex-direction: column; gap: 60px; }
.product-feature {
    display: flex; align-items: center; gap: 48px;
}
.product-feature:nth-child(even) { flex-direction: row-reverse; }
.product-feature-text { flex: 1; }
.product-feature-text h3 { font-size: 1.6rem; font-weight: 700; color: #1a1a2e; margin-bottom: 12px; }
.product-feature-text p { font-size: .95rem; color: #555; line-height: 1.8; }
.product-feature-visual {
    flex: 1; background: linear-gradient(135deg, #e3f2fd, #bbdefb);
    border-radius: 16px; padding: 40px; text-align: center; min-height: 240px;
    display: flex; align-items: center; justify-content: center; font-size: 3rem;
}
.version-table { width: 100%; border-collapse: collapse; margin-top: 20px; }
.version-table th, .version-table td {
    padding: 14px 20px; text-align: left; border-bottom: 1px solid #e8ecf1;
}
.version-table th { background: #f5f7fa; font-weight: 600; color: #1a1a2e; font-size: .92rem; }
.version-table td { font-size: .9rem; color: #555; }
.version-table tr:hover td { background: #fafbfc; }
.check { color: #1a73e8; font-weight: 700; }
.cross { color: #ccc; }

/* === Help Page === */
.help-categories { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: 60px; }
.help-cat-card {
    padding: 28px; background: #fff; border-radius: 12px; border: 1px solid #e8ecf1;
    text-align: center; transition: all .3s;
}
.help-cat-card:hover { transform: translateY(-4px); box-shadow: 0 8px 28px rgba(0,0,0,.08); border-color: #1a73e8; }
.help-cat-icon { font-size: 2rem; margin-bottom: 12px; }
.help-cat-card h3 { font-size: 1.05rem; font-weight: 600; color: #1a1a2e; margin-bottom: 6px; }
.help-cat-card p { font-size: .85rem; color: #999; }

/* === About Page === */
.about-content { max-width: 800px; margin: 0 auto; }
.about-block { margin-bottom: 48px; }
.about-block h3 { font-size: 1.5rem; font-weight: 700; color: #1a1a2e; margin-bottom: 16px; }
.about-block p { font-size: .95rem; color: #555; line-height: 1.8; margin-bottom: 12px; }
.about-values { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 24px; }
.about-value {
    padding: 24px; background: #f5f7fa; border-radius: 10px; text-align: center;
}
.about-value h4 { font-size: 1rem; font-weight: 600; color: #1a73e8; margin-bottom: 8px; }
.about-value p { font-size: .88rem; color: #666; }

/* === Responsive === */
@media (max-width: 1024px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
    .trust-grid { grid-template-columns: repeat(3, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .showcase { flex-direction: column; }
    .product-feature, .product-feature:nth-child(even) { flex-direction: column; }
}
@media (max-width: 768px) {
    .hero h1 { font-size: 2.2rem; }
    .hero .subtitle { font-size: 1.05rem; }
    .section { padding: 56px 0; }
    .section-title h2 { font-size: 1.7rem; }
    .features-grid { grid-template-columns: 1fr; }
    .trust-grid { grid-template-columns: 1fr; }
    .download-grid { grid-template-columns: 1fr; }
    .help-categories { grid-template-columns: 1fr; }
    .about-values { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .nav-links { display: none; }
    .platforms-grid { gap: 16px; }
    .platform-item { min-width: 140px; padding: 20px 24px; }
    .page-header h1 { font-size: 2rem; }
}