/* style.css - 3377体育(中国)官方网站 完整样式 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: 'Segoe UI', system-ui, -apple-system, sans-serif; line-height: 1.6; color: #1a1a2e; background: #f8f9fa; transition: background 0.3s, color 0.3s; }
body.dark-mode { background: #0f0f1a; color: #e0e0e0; }
a { text-decoration: none; color: inherit; }
img, svg { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
/* Header & Nav */
header { position: fixed; top: 0; left: 0; width: 100%; z-index: 1000; background: rgba(255,255,255,0.85); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-bottom: 1px solid rgba(0,0,0,0.05); transition: background 0.3s, box-shadow 0.3s; }
body.dark-mode header { background: rgba(15,15,26,0.85); border-bottom: 1px solid rgba(255,255,255,0.05); }
header.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.08); }
nav { display: flex; align-items: center; justify-content: space-between; padding: 12px 0; flex-wrap: wrap; }
.logo { display: flex; align-items: center; gap: 10px; font-size: 1.5rem; font-weight: 700; color: #1a1a2e; }
body.dark-mode .logo { color: #e0e0e0; }
.logo svg { width: 40px; height: 40px; }
.nav-links { display: flex; gap: 24px; align-items: center; flex-wrap: wrap; }
.nav-links a { font-size: 0.95rem; font-weight: 500; padding: 6px 0; border-bottom: 2px solid transparent; transition: border-color 0.2s, color 0.2s; }
.nav-links a:hover, .nav-links a.active { border-bottom-color: #e94560; color: #e94560; }
.dark-toggle { background: none; border: 1px solid #ccc; border-radius: 20px; padding: 4px 12px; cursor: pointer; font-size: 0.9rem; transition: 0.2s; }
.dark-toggle:hover { background: #e94560; color: #fff; border-color: #e94560; }
.menu-toggle { display: none; background: none; border: none; font-size: 1.5rem; cursor: pointer; }
@media (max-width: 768px) {
    .nav-links { display: none; flex-direction: column; width: 100%; gap: 12px; padding: 16px 0; }
    .nav-links.open { display: flex; }
    .menu-toggle { display: block; }
}
/* Hero Banner */
.hero { padding: 120px 0 80px; background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%); color: #fff; text-align: center; position: relative; overflow: hidden; }
body.dark-mode .hero { background: linear-gradient(135deg, #0a0a1a 0%, #0f1a30 50%, #0a2540 100%); }
.hero::after { content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%; background: radial-gradient(circle at 30% 40%, rgba(233,69,96,0.15) 0%, transparent 60%); pointer-events: none; }
.hero-content { position: relative; z-index: 1; }
.hero h1 { font-size: 3rem; font-weight: 800; margin-bottom: 16px; line-height: 1.2; }
.hero p { font-size: 1.2rem; max-width: 700px; margin: 0 auto 32px; opacity: 0.9; }
.hero .btn-group { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero .btn { padding: 14px 36px; border-radius: 40px; font-weight: 600; font-size: 1rem; transition: 0.3s; cursor: pointer; border: none; }
.hero .btn-primary { background: #e94560; color: #fff; box-shadow: 0 8px 24px rgba(233,69,96,0.3); }
.hero .btn-primary:hover { transform: translateY(-3px); box-shadow: 0 12px 32px rgba(233,69,96,0.4); }
.hero .btn-secondary { background: rgba(255,255,255,0.15); backdrop-filter: blur(8px); color: #fff; border: 1px solid rgba(255,255,255,0.2); }
.hero .btn-secondary:hover { background: rgba(255,255,255,0.25); }
.hero-banner { margin-top: 40px; border-radius: 20px; overflow: hidden; box-shadow: 0 20px 60px rgba(0,0,0,0.3); }
.hero-banner svg { width: 100%; height: auto; display: block; }
/* Section common */
section { padding: 80px 0; }
.section-title { text-align: center; font-size: 2.2rem; font-weight: 700; margin-bottom: 12px; }
.section-subtitle { text-align: center; font-size: 1.1rem; opacity: 0.7; margin-bottom: 48px; max-width: 700px; margin-left: auto; margin-right: auto; }
/* Brand / About */
.brand-grid, .features-grid, .cases-grid, .team-grid, .news-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 32px; }
.brand-card, .feature-card, .case-card, .team-card, .news-card { background: #fff; border-radius: 20px; padding: 32px; box-shadow: 0 8px 30px rgba(0,0,0,0.05); transition: transform 0.3s, box-shadow 0.3s; backdrop-filter: blur(8px); border: 1px solid rgba(255,255,255,0.3); }
body.dark-mode .brand-card, body.dark-mode .feature-card, body.dark-mode .case-card, body.dark-mode .team-card, body.dark-mode .news-card { background: rgba(30,30,50,0.7); border-color: rgba(255,255,255,0.05); }
.brand-card:hover, .feature-card:hover, .case-card:hover, .team-card:hover, .news-card:hover { transform: translateY(-8px); box-shadow: 0 16px 40px rgba(0,0,0,0.1); }
.brand-card svg, .feature-card svg, .case-card svg, .team-card svg { width: 60px; height: 60px; margin-bottom: 16px; }
.brand-card h3, .feature-card h3, .case-card h3, .team-card h3, .news-card h3 { font-size: 1.3rem; margin-bottom: 8px; }
.brand-card p, .feature-card p, .case-card p, .team-card p, .news-card p { opacity: 0.8; line-height: 1.7; }
/* Timeline */
.timeline { position: relative; padding-left: 40px; border-left: 3px solid #e94560; }
.timeline-item { margin-bottom: 32px; position: relative; }
.timeline-item::before { content: ''; position: absolute; left: -46px; top: 6px; width: 14px; height: 14px; background: #e94560; border-radius: 50%; border: 3px solid #fff; }
body.dark-mode .timeline-item::before { border-color: #0f0f1a; }
.timeline-item h4 { font-size: 1.1rem; font-weight: 600; }
.timeline-item span { display: block; font-size: 0.85rem; opacity: 0.6; margin-bottom: 4px; }
/* FAQ */
.faq-item { background: #fff; border-radius: 16px; margin-bottom: 12px; box-shadow: 0 2px 10px rgba(0,0,0,0.04); overflow: hidden; transition: 0.3s; }
body.dark-mode .faq-item { background: rgba(30,30,50,0.7); }
.faq-question { padding: 20px 24px; font-weight: 600; cursor: pointer; display: flex; justify-content: space-between; align-items: center; }
.faq-question::after { content: '+'; font-size: 1.5rem; transition: transform 0.3s; }
.faq-item.active .faq-question::after { transform: rotate(45deg); }
.faq-answer { padding: 0 24px 20px; display: none; line-height: 1.7; }
.faq-item.active .faq-answer { display: block; }
/* HowTo */
.howto-steps { counter-reset: step; }
.howto-step { background: #fff; border-radius: 16px; padding: 24px; margin-bottom: 16px; box-shadow: 0 2px 10px rgba(0,0,0,0.04); display: flex; gap: 20px; align-items: flex-start; }
body.dark-mode .howto-step { background: rgba(30,30,50,0.7); }
.howto-step::before { counter-increment: step; content: counter(step); background: #e94560; color: #fff; width: 36px; height: 36px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: 700; flex-shrink: 0; }
.howto-step h4 { font-size: 1.1rem; margin-bottom: 4px; }
.howto-step p { opacity: 0.8; }
/* Footer */
footer { background: #1a1a2e; color: #ccc; padding: 60px 0 30px; }
body.dark-mode footer { background: #0a0a1a; }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 32px; margin-bottom: 32px; }
.footer-grid h4 { color: #fff; margin-bottom: 16px; font-size: 1.1rem; }
.footer-grid a { display: block; margin-bottom: 8px; opacity: 0.7; transition: opacity 0.2s; }
.footer-grid a:hover { opacity: 1; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); padding-top: 24px; text-align: center; font-size: 0.9rem; }
.footer-bottom a { color: #e94560; }
/* Back to top */
.back-to-top { position: fixed; bottom: 30px; right: 30px; width: 48px; height: 48px; border-radius: 50%; background: #e94560; color: #fff; display: flex; align-items: center; justify-content: center; font-size: 1.5rem; cursor: pointer; border: none; box-shadow: 0 4px 16px rgba(233,69,96,0.3); opacity: 0; visibility: hidden; transition: 0.3s; z-index: 999; }
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { transform: scale(1.1); }
/* Numbers */
.numbers-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 24px; text-align: center; }
.number-item h2 { font-size: 2.5rem; color: #e94560; font-weight: 800; }
.number-item p { opacity: 0.7; margin-top: 4px; }
/* Breadcrumb */
.breadcrumb { padding: 16px 0; font-size: 0.9rem; opacity: 0.7; }
.breadcrumb span { margin: 0 6px; }
/* Glass cards */
.glass-card { background: rgba(255,255,255,0.6); backdrop-filter: blur(12px); border: 1px solid rgba(255,255,255,0.3); border-radius: 24px; padding: 32px; box-shadow: 0 8px 32px rgba(0,0,0,0.06); }
body.dark-mode .glass-card { background: rgba(30,30,50,0.4); border-color: rgba(255,255,255,0.05); }
/* Animations */
.fade-up { opacity: 0; transform: translateY(30px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-up.visible { opacity: 1; transform: translateY(0); }
/* Partner logos */
.partner-logos { display: flex; flex-wrap: wrap; gap: 24px; justify-content: center; align-items: center; }
.partner-logos svg { width: 100px; height: 60px; opacity: 0.5; transition: opacity 0.3s; }
.partner-logos svg:hover { opacity: 1; }
/* Responsive */
@media (max-width: 768px) {
    .hero h1 { font-size: 2rem; }
    .hero p { font-size: 1rem; }
    .section-title { font-size: 1.8rem; }
    .brand-grid, .features-grid, .cases-grid, .team-grid, .news-grid { grid-template-columns: 1fr; }
    .timeline { padding-left: 24px; }
    .timeline-item::before { left: -30px; }
}