* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.6;
    color: #333;
    background: #fff;
    overflow-x: hidden;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 响应式断点 */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }
}

/* 头部导航 - 移动端优化 */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.header.scrolled {
    padding: 5px 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

.header .logo {
    font-size: 24px;
    font-weight: bold;
    color: #FF6B00;
}

.header .nav {
    display: flex;
    gap: 30px;
}

.header .nav a {
    color: #333;
    text-decoration: none;
    font-size: 16px;
    position: relative;
    padding: 5px 0;
}

.header .nav a:after {
    content: '';
    position: absolute;
    bottom: 8px;
    left: 0;
    width: 0;
    height: 2px;
    background: #FF6B00;
    transition: width 0.3s ease;
}

.header .nav a:hover:after {
    width: 100%;
}

.header .nav a.active:after {
    width: 100%;
}

.contact-btn {
    background: #FF6B00;
    color: white;
    padding: 8px 20px;
    border-radius: 4px;
    text-decoration: none;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.contact-btn:hover {
    background: #e55a00;
    transform: translateY(-2px);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    z-index: 1001;
}

@media (max-width: 768px) {
    .nav {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: white;
        flex-direction: column;
        padding: 80px 20px 20px;
        box-shadow: 0 5px 15px rgba(0,0,0,0.1);
        z-index: 999;
        overflow-y: auto;
    }

    .nav.active {
        display: flex;
    }

    .nav a {
        padding: 15px 0;
        font-size: 18px;
        border-bottom: 1px solid #f0f0f0;
    }

    .mobile-menu-btn {
        display: block;
    }

    .header .container {
        padding: 12px 15px;
    }

    .logo {
        font-size: 20px;
    }

    .contact-btn {
        padding: 6px 15px;
        font-size: 14px;
    }
}