:root {
    --primary-blue: #1a73e8;
    --light-blue: #e8f0fe;
    --dark-blue: #0d47a1;
    --accent: #34a853;
    --text-dark: #202124;
    --text-light: #5f6368;
    --white: #ffffff;
    --light-gray: #f8f9fa;
    --border-radius: 12px;
    --box-shadow: 0 4px 12px 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: var(--white);
    color: var(--text-dark);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

main {
    flex: 1;
}

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

.section-padding {
    padding: 80px 0;
}

/* 导航栏样式 */
header {
    background-color: var(--white);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

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

.logo img {
    height: 40px;
}

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

.nav-item {
    margin-left: 30px;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
    padding: 6px 0;
}

.nav-link:hover {
    color: var(--primary-blue);
}

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

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

.nav-link.active {
    color: var(--primary-blue);
}

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

.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    background-color: var(--text-dark);
    transition: var(--transition);
}

/* 按钮样式 */
.btn {
    padding: 14px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    display: inline-block;
    text-align: center;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background-color: var(--primary-blue);
    color: var(--white);
    box-shadow: 0 4px 14px rgba(26, 115, 232, 0.4);
}

.btn-primary:hover {
    background-color: var(--dark-blue);
    transform: translateY(-3px);
    box-shadow: 0 6px 18px rgba(26, 115, 232, 0.5);
}

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

.btn-outline:hover {
    background-color: var(--primary-blue);
    color: var(--white);
    transform: translateY(-3px);
}

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

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--white);
}

.footer-desc {
    margin-bottom: 20px;
    color: #bdc1c6;
}

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

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--white);
    transition: var(--transition);
}

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

.footer-heading {
    font-size: 1.2rem;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-heading::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background-color: var(--primary-blue);
}

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

.footer-links li {
    margin-bottom: 12px;
}

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

.footer-links a:hover {
    color: var(--primary-blue);
    padding-left: 5px;
}

/* 备案信息样式 */
.footer-legal {
    background-color: rgba(0, 0, 0, 0.2);
    padding: 20px 0;
    text-align: center;
}

.legal-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 15px;
}

.legal-links a {
    color: #bdc1c6;
    text-decoration: none;
    font-size: 0.9rem;
    transition: var(--transition);
}

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

.copyright {
    color: #bdc1c6;
    font-size: 0.9rem;
}

.footer-bottom {
    padding: 30px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* 响应式设计 */
@media (max-width: 968px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }

    .hero-text {
        padding-right: 0;
        margin-bottom: 40px;
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-title {
        font-size: 2.5rem;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-heading::after {
        left: 50%;
        transform: translateX(-50%);
    }
    
    .legal-links {
        flex-direction: column;
        gap: 10px;
    }
}

@media (max-width: 768px) {
    .hamburger {
        display: block;
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 80px;
        gap: 0;
        flex-direction: column;
        background-color: var(--white);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 20px 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-item {
        margin: 20px 0;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-desc {
        font-size: 1rem;
    }

    .section-title h2 {
        font-size: 2rem;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-heading::after {
        left: 50%;
        transform: translateX(-50%);
    }
    
    .legal-links {
        flex-direction: column;
        gap: 10px;
    }
}