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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all 0.3s ease;
}

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

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-img {
    width: 48px;
    height: 48px;
}

.logo-text {
    font-size: 24px;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    gap: 30px;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-link:hover {
    color: #667eea;
}

/* 语言切换器 */
.language-switcher {
    display: flex;
    gap: 5px;
    background: #f5f5f5;
    border-radius: 25px;
    padding: 3px;
}

.lang-btn {
    background: none;
    border: none;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
    color: #666;
    cursor: pointer;
    transition: all 0.3s ease;
}

.lang-btn:hover {
    color: #333;
}

.lang-btn.active {
    background: #667eea;
    color: white;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.3);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* 英雄区域 */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content {
    animation: fadeInUp 1s ease;
}

.hero-title {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 20px;
    opacity: 0.9;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 40px;
    opacity: 0.8;
    line-height: 1.8;
    max-width: 500px;
    text-align: left;
    text-align: center;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 15px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

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

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

.btn-download {
    background: #667eea;
    color: white;
    margin: 5px;
}

.btn-download:hover {
    background: #5a6fd8;
    transform: translateY(-2px);
}

.btn-store {
    background: #000;
    color: white;
    margin: 5px;
}

.btn-store:hover {
    background: #333;
    transform: translateY(-2px);
}

/* 手机模拟器 */
.phone-mockup {
    width: 300px;
    height: 600px;
    background: #1a1a1a;
    border-radius: 30px;
    padding: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
    animation: fadeInRight 1s ease;
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: white;
    border-radius: 20px;
    overflow: hidden;
}

.chat-interface {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.chat-header {
    background: #667eea;
    color: white;
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.avatar {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.3);
    border-radius: 50%;
}

.chat-info h4 {
    margin: 0;
    font-size: 16px;
}

.chat-info p {
    margin: 0;
    font-size: 12px;
    opacity: 0.8;
}

.chat-messages {
    flex: 1;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.message {
    max-width: 80%;
    padding: 12px 16px;
    border-radius: 18px;
    position: relative;
}

.message.received {
    background: #f0f0f0;
    align-self: flex-start;
}

.message.sent {
    background: #667eea;
    color: white;
    align-self: flex-end;
}

.message p {
    margin: 0;
    font-size: 14px;
}

.message .time {
    font-size: 10px;
    opacity: 0.7;
    position: absolute;
    bottom: -20px;
    right: 0;
}

/* 功能特色 */
.features {
    padding: 100px 0;
    background: #f8f9fa;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: #333;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.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 ease;
}

.feature-card:hover {
    transform: translateY(-10px);
}

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

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #333;
}

.feature-card p {
    color: #666;
    line-height: 1.6;
}

/* 下载区域 */
.download {
    padding: 100px 0;
    background: white;
}

.download-subtitle {
    text-align: center;
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 60px;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 60px;
}

.download-card {
    background: #f8f9fa;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: transform 0.3s ease;
    border: 2px solid transparent;
}

.download-card:hover {
    transform: translateY(-5px);
    border-color: #667eea;
}

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

.download-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: #333;
}

.download-card p {
    color: #666;
    margin-bottom: 20px;
}

.download-buttons {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

/* 关于我们 */
.about {
    padding: 100px 0;
    background: #f8f9fa;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-text h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 30px;
    color: #333;
}

.about-text p {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 20px;
    line-height: 1.8;
}

.stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 40px;
}

.stat {
    text-align: center;
}

.stat h3 {
    font-size: 2rem;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 10px;
}

.stat p {
    color: #666;
    font-weight: 500;
}

.about-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.image-placeholder {
    width: 300px;
    height: 300px;
    background: white;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

/* 联系我们 */
.contact {
    padding: 100px 0;
    background: white;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    margin-top: 60px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.contact-item h4 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: #333;
}

.contact-item p {
    color: #666;
    font-size: 1.1rem;
}

.contact-form {
    background: #f8f9fa;
    padding: 40px;
    border-radius: 20px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    margin-bottom: 20px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.contact-form input:focus,
.contact-form textarea:focus {
    outline: none;
    border-color: #667eea;
}

.contact-form textarea {
    resize: vertical;
    min-height: 120px;
}

/* 页脚 */
.footer {
    background: #1a1a1a;
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

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

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

.footer-social {
    display: flex;
    gap: 20px;
}

.social-link {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-legal {
    display: flex;
    gap: 20px;
    margin-top: 10px;
}

.legal-link {
    color: #999;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
}

.legal-link:hover {
    color: #667eea;
}

.social-link:hover {
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #333;
    color: #999;
}

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

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .language-switcher {
        order: -1;
        margin-right: 10px;
    }
    
    .lang-btn {
        padding: 6px 12px;
        font-size: 12px;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .phone-mockup {
        width: 250px;
        height: 500px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .download-grid {
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    }
    
    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .stats {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 0.9rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
}