:root { --primary: #0066cc; --primary-dark: #0052a3; --primary-light: #e6f0ff; --secondary: #00a0e9; --accent: #ff6600; --text-dark: #333; --text-light: #666; --text-lightest: #999; --bg-light: #f5f7fa; --bg-white: #fff; --border-color: #e5e7eb; --shadow: 0 2px 8px rgba(0,0,0,0.1); --shadow-lg: 0 8px 30px rgba(0,0,0,0.12); --radius: 8px; --transition: all 0.3s ease; }
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: 'Microsoft YaHei', 'PingFang SC', -apple-system, BlinkMacSystemFont, sans-serif; color: var(--text-dark); line-height: 1.6; overflow-x: hidden; background: var(--bg-white); }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.btn { display: inline-block; padding: 12px 30px; border-radius: 4px; font-size: 16px; cursor: pointer; transition: var(--transition); border: none; text-align: center; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: var(--shadow); }
.section-header { text-align: center; margin-bottom: 60px; }
.section-title { font-size: 36px; color: var(--text-dark); margin-bottom: 15px; font-weight: 600; }
.section-subtitle { font-size: 18px; color: var(--text-light); }

.header { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; background: rgba(255,255,255,0.98); backdrop-filter: blur(10px); box-shadow: 0 1px 3px rgba(0,0,0,0.1); transition: var(--transition); }
.header.scrolled { background: rgba(255,255,255,0.95); }
.header-inner { display: flex; justify-content: space-between; align-items: center; height: 80px; }
.logo img { height: 40px; }
.nav-list { display: flex; gap: 40px; }
.nav-list a { font-size: 16px; color: var(--text-dark); font-weight: 500; position: relative; padding: 5px 0; }
.nav-list a::after { content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px; background: var(--primary); transition: var(--transition); }
.nav-list a:hover::after, .nav-list a.active::after { width: 100%; }
.nav-list a:hover { color: var(--primary); }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 10px; }
.nav-toggle span { width: 25px; height: 3px; background: var(--text-dark); border-radius: 2px; transition: var(--transition); }

.hero { position: relative; height: 100vh; min-height: 600px; display: flex; align-items: center; justify-content: center; overflow: hidden; }
.hero-slider { position: absolute; top: 0; left: 0; right: 0; bottom: 0; }
.hero-slide { position: absolute; top: 0; left: 0; right: 0; bottom: 0; background-size: cover; background-position: center; opacity: 0; transition: opacity 1s ease; }
.hero-slide.active { opacity: 1; }
.hero-slide::before { content: ''; position: absolute; top: 0; left: 0; right: 0; bottom: 0; background: linear-gradient(135deg, rgba(0,102,204,0.85) 0%, rgba(0,160,233,0.75) 100%); }
.hero-content { position: relative; z-index: 10; text-align: center; color: #fff; padding: 0 20px; }
.hero-content h1 { font-size: 56px; font-weight: 700; margin-bottom: 20px; text-shadow: 0 2px 10px rgba(0,0,0,0.3); animation: fadeInUp 0.8s ease; }
.hero-content p { font-size: 24px; margin-bottom: 40px; opacity: 0.95; animation: fadeInUp 0.8s ease 0.2s both; }
.hero-content .btn { animation: fadeInUp 0.8s ease 0.4s both; }
.hero-indicator { position: absolute; bottom: 40px; left: 50%; transform: translateX(-50%); display: flex; gap: 10px; z-index: 10; }
.indicator { width: 12px; height: 12px; border-radius: 50%; background: rgba(255,255,255,0.5); cursor: pointer; transition: var(--transition); }
.indicator.active { background: #fff; transform: scale(1.2); }

.industries { padding: 100px 0; background: var(--bg-white); }
.industry-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 30px; }
.industry-card { background: var(--bg-white); border-radius: var(--radius); padding: 40px 25px; text-align: center; box-shadow: var(--shadow); transition: var(--transition); cursor: pointer; position: relative; overflow: hidden; }
.industry-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: var(--primary); transform: scaleX(0); transition: var(--transition); }
.industry-card:hover { transform: translateY(-10px); box-shadow: var(--shadow-lg); }
.industry-card:hover::before { transform: scaleX(1); }
.industry-icon { width: 80px; height: 80px; margin: 0 auto 25px; background: var(--primary-light); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 36px; transition: var(--transition); }
.industry-card:hover .industry-icon { background: var(--primary); transform: scale(1.1); }
.industry-card:hover .industry-icon::before { filter: brightness(10); }
.industry-card h3 { font-size: 20px; color: var(--text-dark); margin-bottom: 15px; font-weight: 600; }
.industry-card p { font-size: 14px; color: var(--text-light); line-height: 1.8; }
.industry-card .card-detail { max-height: 0; overflow: hidden; transition: max-height 0.5s ease; }
.industry-card:hover .card-detail { max-height: 200px; margin-top: 15px; }

.about { padding: 100px 0; background: var(--bg-light); }
.about-content { max-width: 800px; margin: 0 auto; text-align: center; }
.about-content h2 { font-size: 36px; color: var(--text-dark); margin-bottom: 30px; }
.about-content p { font-size: 18px; color: var(--text-light); line-height: 1.8; margin-bottom: 50px; }
.about-stats { display: flex; justify-content: center; gap: 80px; }
.stat-item { text-align: center; }
.stat-number { display: block; font-size: 48px; font-weight: 700; color: var(--primary); }
.stat-label { font-size: 16px; color: var(--text-light); }

.products { padding: 100px 0; background: var(--bg-white); }
.products-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; }
.product-card { background: var(--bg-white); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 40px 30px; text-align: center; transition: var(--transition); }
.product-card:hover { border-color: var(--primary); box-shadow: var(--shadow); transform: translateY(-5px); }
.product-icon { font-size: 48px; margin-bottom: 20px; }
.product-card h3 { font-size: 20px; color: var(--text-dark); margin-bottom: 15px; font-weight: 600; }
.product-card p { font-size: 14px; color: var(--text-light); line-height: 1.6; }

.contact { padding: 100px 0; background: var(--bg-light); }
.contact-wrapper { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: start; }
.contact-info { display: flex; flex-direction: column; gap: 30px; }
.contact-item { display: flex; gap: 20px; align-items: flex-start; }
.contact-icon { width: 50px; height: 50px; background: var(--primary); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 24px; flex-shrink: 0; }
.contact-item h4 { font-size: 18px; color: var(--text-dark); margin-bottom: 5px; }
.contact-item p { font-size: 16px; color: var(--text-light); }
.contact-form { background: var(--bg-white); padding: 40px; border-radius: var(--radius); box-shadow: var(--shadow); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-bottom: 20px; }
.contact-form input, .contact-form textarea { width: 100%; padding: 15px; border: 1px solid var(--border-color); border-radius: 4px; font-size: 16px; font-family: inherit; transition: var(--transition); }
.contact-form input:focus, .contact-form textarea:focus { outline: none; border-color: var(--primary); }
.contact-form textarea { margin-bottom: 20px; resize: vertical; }
.contact-form .btn { width: 100%; }

.footer { background: #1a252f; color: #ecf0f1; padding: 60px 0 0; }
.footer-content { display: grid; grid-template-columns: 1fr 2fr; gap: 60px; margin-bottom: 50px; }
.footer-logo { height: 40px; margin-bottom: 20px; filter: brightness(10); }
.footer-brand p { color: #95a5a6; }
.footer-links { display: grid; grid-template-columns: repeat(3, 1fr); gap: 40px; }
.footer-col h4 { font-size: 18px; margin-bottom: 25px; color: #fff; }
.footer-col ul li { margin-bottom: 12px; }
.footer-col ul li a { color: #95a5a6; font-size: 14px; }
.footer-col ul li a:hover { color: var(--primary); }
.footer-bottom { border-top: 1px solid #34495e; padding: 25px 0; text-align: center; color: #7f8c8d; font-size: 14px; }

.back-to-top { position: fixed; bottom: 30px; right: 30px; width: 50px; height: 50px; background: var(--primary); color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 24px; cursor: pointer; opacity: 0; visibility: hidden; transition: var(--transition); z-index: 999; }
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { background: var(--primary-dark); transform: translateY(-3px); }

@keyframes fadeInUp { from { opacity: 0; transform: translateY(30px); } to { opacity: 1; transform: translateY(0); } }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.animate-on-scroll { opacity: 0; transform: translateY(30px); transition: all 0.6s ease; }
.animate-on-scroll.animated { opacity: 1; transform: translateY(0); }

@media (max-width: 1024px) {
    .industry-grid { grid-template-columns: repeat(3, 1fr); }
    .products-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-content { grid-template-columns: 1fr; }
    .footer-links { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .nav-toggle { display: flex; }
    .nav { position: fixed; top: 80px; left: 0; right: 0; background: var(--bg-white); padding: 20px; box-shadow: var(--shadow); transform: translateY(-100%); opacity: 0; visibility: hidden; transition: var(--transition); }
    .nav.active { transform: translateY(0); opacity: 1; visibility: visible; }
    .nav-list { flex-direction: column; gap: 15px; }
    .hero-content h1 { font-size: 36px; }
    .hero-content p { font-size: 18px; }
    .industry-grid { grid-template-columns: repeat(2, 1fr); gap: 20px; }
    .industry-card { padding: 30px 20px; }
    .about-stats { flex-direction: column; gap: 30px; }
    .products-grid { grid-template-columns: 1fr; }
    .contact-wrapper { grid-template-columns: 1fr; }
    .footer-links { grid-template-columns: 1fr; gap: 30px; }
    .section-title { font-size: 28px; }
}

@media (max-width: 480px) {
    .header-inner { height: 60px; }
    .logo img { height: 30px; }
    .hero { min-height: 500px; }
    .hero-content h1 { font-size: 28px; }
    .hero-content p { font-size: 16px; }
    .industry-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
    .contact-form { padding: 25px; }
}