/* 欧易钱包官网样式 - SEO优化版 */

/* CSS重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.header {
    background: linear-gradient(135deg, #1652f0 0%, #0f3cc9 100%);
    color: white;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo h1 {
    font-size: 24px;
    font-weight: 700;
}

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

.nav-menu a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #e0e7ff;
}

/* 主要内容区域 */
main {
    margin-top: 70px;
}

/* 首页横幅 */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 100px 0 80px;
    text-align: center;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.hero-content h2 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-content p {
    font-size: 18px;
    margin-bottom: 30px;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
}

.btn {
    display: inline-block;
    padding: 15px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    text-align: center;
}

.btn-primary {
    background: #ff6b35;
    color: white;
    box-shadow: 0 4px 15px rgba(255, 107, 53, 0.3);
}

.btn-primary:hover {
    background: #e55a2b;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 107, 53, 0.4);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #667eea;
}

.hero-image img {
    max-width: 50%;
    height: auto;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.2);
}

/* 功能特色 */
.features {
    padding: 80px 0;
    background: #f8fafc;
}

.features h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 60px;
    color: #1a202c;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.feature-card {
    background: white;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 24px;
    margin-bottom: 15px;
    color: #1a202c;
}

.feature-card p {
    color: #718096;
    line-height: 1.6;
}

/* 下载区域 */
.download {
    padding: 80px 0;
    background: white;
}

.download h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 20px;
    color: #1a202c;
}

.download p {
    text-align: center;
    font-size: 18px;
    color: #718096;
    margin-bottom: 60px;
}

.download-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.download-card {
    background: #f8fafc;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: transform 0.3s;
}

.download-card:hover {
    transform: translateY(-5px);
}

.platform-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.download-card h3 {
    font-size: 24px;
    margin-bottom: 10px;
    color: #1a202c;
}

.download-card p {
    color: #718096;
    margin-bottom: 20px;
}

.btn-download {
    background: #1652f0;
    color: white;
    box-shadow: 0 4px 15px rgba(22, 82, 240, 0.3);
}

.btn-download:hover {
    background: #0f3cc9;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(22, 82, 240, 0.4);
}

/* 使用教程 */
.tutorial {
    padding: 80px 0;
    background: #f8fafc;
}

.tutorial h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 60px;
    color: #1a202c;
}

.tutorial-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.tutorial-step {
    background: white;
    padding: 30px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
}

.step-number {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #1652f0 0%, #0f3cc9 100%);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: 700;
    margin: 0 auto 20px;
}

.tutorial-step h3 {
    font-size: 20px;
    margin-bottom: 15px;
    color: #1a202c;
}

.tutorial-step p {
    color: #718096;
    line-height: 1.6;
}

/* 最新资讯 */
.news {
    padding: 80px 0;
    background: white;
}

.news h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 60px;
    color: #1a202c;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.news-card {
    background: white;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.news-card:hover {
    transform: translateY(-5px);
}

.news-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.news-card h3 {
    padding: 20px 20px 10px;
    font-size: 20px;
    color: #1a202c;
}

.news-card p {
    padding: 0 20px;
    color: #718096;
    line-height: 1.6;
}

.news-card a {
    display: block;
    padding: 10px 20px 20px;
    color: #1652f0;
    text-decoration: none;
    font-weight: 600;
}

.news-card a:hover {
    color: #0f3cc9;
}

/* 帮助中心 */
.support {
    padding: 80px 0;
    background: #f8fafc;
}

.support h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 60px;
    color: #1a202c;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.faq-item {
    background: white;
    padding: 30px;
    border-radius: 20px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
}

.faq-item h3 {
    font-size: 18px;
    margin-bottom: 15px;
    color: #1a202c;
}

.faq-item p {
    color: #718096;
    line-height: 1.6;
}

/* 页脚 */
.footer {
    background: #1a202c;
    color: white;
    padding: 60px 0 20px;
}

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

.footer-section h4 {
    font-size: 18px;
    margin-bottom: 20px;
    color: #e2e8f0;
}

.footer-section p {
    color: #a0aec0;
    line-height: 1.6;
    margin-bottom: 20px;
}

.footer-section ul {
    list-style: none;
}

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

.footer-section ul li a {
    color: #a0aec0;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section ul li a:hover {
    color: #e2e8f0;
}

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

.social-links a {
    font-size: 24px;
    transition: transform 0.3s;
}

.social-links a:hover {
    transform: scale(1.2);
}

.footer-bottom {
    border-top: 1px solid #2d3748;
    padding-top: 20px;
    text-align: center;
}

.footer-bottom p {
    color: #a0aec0;
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: #1652f0;
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 20px;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    z-index: 1000;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none; /* 移动端可以添加汉堡菜单 */
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 30px;
    }

    .hero-content h2 {
        font-size: 32px;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .features-grid,
    .download-options,
    .tutorial-grid,
    .news-grid,
    .faq-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .social-links {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero {
        padding: 60px 0 40px;
    }

    .hero-content h2 {
        font-size: 28px;
    }

    .hero-content p {
        font-size: 16px;
    }

    .features,
    .download,
    .tutorial,
    .news,
    .support {
        padding: 40px 0;
    }

    .features h2,
    .download h2,
    .tutorial h2,
    .news h2,
    .support h2 {
        font-size: 28px;
    }
}

/* 加载动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* 图片懒加载占位符 */
.lazy-loading {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
}

@keyframes loading {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}