:root { --primary: #ff5722; --dark-bg: #2d3035; --text-dark: #333; --text-light: #666; --bg-light: #f8f9fa; --white: #fff; }
* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Microsoft YaHei', sans-serif; }
body { color: var(--text-dark); line-height: 1.8; padding-bottom: 60px; word-wrap: break-word; }
a { text-decoration: none; color: inherit; transition: 0.3s; }
ul { list-style: none; }
img { max-width: 100%; height: auto; }

/* 导航栏 */
header { background: var(--dark-bg); position: sticky; top: 0; z-index: 1000; color: var(--white); }
.header-container { max-width: 1200px; margin: 0 auto; display: flex; justify-content: space-between; align-items: center; padding: 15px 20px; }
/* 修改这里：Logo颜色改为橙色 */
.logo { font-size: 24px; font-weight: bold; color: var(--primary); }
.main-nav ul { display: flex; gap: 30px; }
.main-nav li { position: relative; cursor: pointer; }
.main-nav li > a { color: #fff; padding: 10px 0; display: block; }
.main-nav li:hover > a { color: var(--primary); }

/* 下拉菜单 */
.dropdown { 
    display: none !important; 
    position: absolute; 
    top: 100%; 
    left: 0; 
    background: var(--dark-bg); 
    padding: 10px 0; 
    min-width: 150px; 
    box-shadow: 0 5px 15px rgba(0,0,0,0.3); 
}
.main-nav li:hover .dropdown { 
    display: block !important; 
}
.dropdown li a { display: block; padding: 10px 20px; color: #ccc !important; }
.dropdown li a:hover { background: var(--primary); color: var(--white) !important; }

.header-btns { display: flex; gap: 15px; }
.btn { padding: 10px 25px; border-radius: 25px; font-size: 14px; cursor: pointer; transition: 0.3s; border: none; font-weight: bold; display:inline-block; text-align:center;}
.btn-primary { background: var(--primary); color: var(--white); }
.btn-primary:hover { background: #e64a19; }
.btn-outline { background: transparent; color: var(--white); border: 1px solid var(--white); }
.btn-outline:hover { background: var(--white); color: var(--dark-bg); }

/* 内容区通用 */
main { min-height: 60vh; }
.section { padding: 60px 10%; }
.section-title { text-align: center; font-size: 32px; margin-bottom: 40px; font-weight: bold; }
.section-title span { color: var(--primary); }
.content-box { max-width: 1000px; margin: 0 auto; font-size: 16px; color: var(--text-light); }
.content-box p { margin-bottom: 20px; text-indent: 2em; }
.content-box h3 { color: var(--text-dark); margin: 30px 0 15px; font-size: 22px; }

/* Hero */
.hero { background: linear-gradient(rgba(0,0,0,0.6), rgba(0,0,0,0.6)), url('https://images.unsplash.com/photo-1486406146926-c627a92ad1ab?q=80&w=1920&auto=format&fit=crop') center/cover; color: var(--white); text-align: center; padding: 120px 20px; }
.hero h1 { font-size: 48px; margin-bottom: 20px; }
.hero p { font-size: 20px; margin-bottom: 40px; }

/* 数据栏 */
.stats-bar { background: #1a1c20; color: #fff; display: flex; justify-content: space-around; padding: 40px 10%; flex-wrap: wrap; text-align: center; }
.stats-bar h4 { color: var(--primary); font-size: 24px; margin-bottom: 5px; }
.stats-bar p { color: #aaa; font-size: 14px; }

/* 卡片排版 (关于我们) */
.features-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; max-width: 1000px; margin: 40px auto 0; }
.feature-item { display: flex; gap: 20px; background: var(--bg-light); padding: 30px; border-radius: 10px; border: 1px solid #eee; }
.feature-icon { width: 60px; height: 60px; background: var(--white); border: 1px solid var(--primary); border-radius: 10px; display: flex; justify-content: center; align-items: center; color: var(--primary); font-size: 24px; flex-shrink: 0; }
.feature-text h3 { font-size: 20px; color: var(--primary); margin-bottom: 10px; }
.feature-text p { color: var(--text-light); font-size: 14px; margin: 0; text-indent: 0; }

/* 交易产品卡片 */
.products-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; max-width: 1200px; margin: 0 auto; }
.product-card { background: var(--white); padding: 40px 30px; text-align: center; border-radius: 10px; box-shadow: 0 5px 15px rgba(0,0,0,0.05); border: 1px solid #f0f0f0;}
.product-card h3 { font-size: 22px; margin-bottom: 15px; }
.product-card p { color: var(--text-light); margin-bottom: 25px; font-size: 14px; }

/* 底部 */
footer { background: #1a1c20; color: #aaa; padding: 60px 10% 20px; font-size: 14px; }
.footer-top { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; border-bottom: 1px solid #333; padding-bottom: 40px; margin-bottom: 20px; }
.footer-top h4 { color: var(--white); margin-bottom: 20px; font-size: 18px; }
.footer-links li { margin-bottom: 12px; }
.footer-links li a:hover { color: var(--primary); }
.footer-bottom { text-align: center; font-size: 13px; color: #666; }

/* 手机端底部固定栏 */
.mobile-bottom-bar { display: none; position: fixed; bottom: 0; left: 0; width: 100%; background: var(--white); box-shadow: 0 -2px 10px rgba(0,0,0,0.1); z-index: 999; padding: 10px; justify-content: space-around; }
.mobile-bottom-bar .btn { width: 45%; padding: 12px 0; }
.mobile-bottom-bar .btn-outline { color: var(--primary); border-color: var(--primary); }

/* 表单 */
.form-group { margin-bottom: 20px; }
.form-group label { display: block; margin-bottom: 8px; font-weight: bold; }
.form-group input, .form-group textarea { width: 100%; padding: 10px; border: 1px solid #ccc; border-radius: 4px; }

@media (max-width: 768px) {
    .main-nav, .header-btns { display: none; }
    .hero h1 { font-size: 32px; }
    .hero p { font-size: 16px; }
    .features-grid, .products-grid { grid-template-columns: 1fr; }
    .footer-top { grid-template-columns: 1fr; }
    .mobile-bottom-bar { display: flex; }
}