/* common.css - 极简基础样式 */
:root {
    --primary: #4CAF50;
    --primary-dark: #388E3C;
    --primary-light: #C8E6C9;
    --accent: #8BC34A;
    --text: #333333;
    --text-light: #666666;
    --bg: #f5f5f5;
    --white: #ffffff;
    --shadow: 0 2px 8px rgba(0,0,0,0.1);
    --radius: 8px;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
}

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

/* 导航栏 */
header {
    background: var(--white);
    box-shadow: var(--shadow);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    padding: 15px 0;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-dark);
    text-decoration: none;
}

.logo span {
    color: var(--accent);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--primary);
}

.mobile-menu {
    display: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--text);
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 12px 24px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius);
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: background 0.3s;
}

.btn:hover {
    background: var(--primary-dark);
}

.btn-secondary {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

.btn-secondary:hover {
    background: var(--primary-light);
}

/* 页脚 */
footer {
    background: var(--text);
    color: white;
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
    margin-bottom: 30px;
}

.footer-column h3 {
    color: white;
    margin-bottom: 20px;
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: white;
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: #ccc;
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        position: fixed;
        top: 60px;
        left: 0;
        width: 100%;
        background: var(--white);
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow);
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .mobile-menu {
        display: block;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
}