:root {
    --primary-color: #1a73e8;
    --secondary-color: #34a853;
    --accent-color: #fbbc05;
    --dark-color: #202124;
    --light-color: #f8f9fa;
    --gray-color: #5f6368;
    --border-radius: 8px;
    --box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

body {
    background-color: #f5f7fa;
    color: var(--dark-color);
    line-height: 1.6;
}

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

/* 导航栏样式 */
header {
    background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo {
    display: flex;
    align-items: center;
}

.logo-icon {
    font-size: 28px;
    margin-right: 10px;
    color: var(--primary-color);
}

.logo-text {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

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

.nav-links li {
    margin-left: 30px;
}

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

.nav-links a:after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

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

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

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

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

.download-btn {
    background-color: var(--primary-color);
    color: white;
    padding: 8px 20px;
    border-radius: var(--border-radius);
    font-weight: 500;
    transition: var(--transition);
}

.download-btn:hover {
    background-color: #0d5bb7;
    transform: translateY(-2px);
}

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

/* 页面标题 */
.page-header {
    background: linear-gradient(135deg, #1a73e8 0%, #6c8ef5 100%);
    color: white;
    padding: 60px 0;
    text-align: center;
}

.page-header h1 {
    font-size: 42px;
    margin-bottom: 15px;
}

.page-header p {
    font-size: 18px;
    max-width: 700px;
    margin: 0 auto;
}

/* 通用部分标题 */
.section-title {
    text-align: center;
    margin-bottom: 60px;
}

.section-title h2 {
    font-size: 36px;
    color: var(--dark-color);
    margin-bottom: 15px;
}

.section-title p {
    color: var(--gray-color);
    max-width: 700px;
    margin: 0 auto;
}

/* 按钮样式 */
.btn {
    padding: 12px 30px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    display: inline-block;
    cursor: pointer;
    border: none;
    text-align: center;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

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

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.btn-primary:hover {
    background-color: #0d5bb7;
}

.btn-secondary:hover {
    background-color: rgba(26, 115, 232, 0.1);
}

/* 页脚样式 */
footer {
    background-color: var(--dark-color);
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column h3 {
    margin-bottom: 20px;
    font-size: 18px;
}

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

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

.footer-links a {
    color: #bdc1c6;
    text-decoration: none;
    transition: var(--transition);
}

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

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    text-decoration: none;
    transition: var(--transition);
}

.social-links a:hover {
    background-color: var(--primary-color);
    transform: translateY(-3px);
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #3c4043;
    color: #9aa0a6;
    font-size: 14px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .nav-links {
        display: none;
        flex-direction: column;
        width: 100%;
        margin-top: 20px;
    }
    
    .nav-links.active {
        display: flex;
    }
    
    .nav-links li {
        margin: 10px 0;
    }
    
    .mobile-menu-btn {
        display: block;
        position: absolute;
        right: 20px;
        top: 20px;
    }
    
    .page-header h1 {
        font-size: 32px;
    }
    
    .page-header p {
        font-size: 16px;
    }
    
    .section-title h2 {
        font-size: 28px;
    }
}