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

/* CSS变量 */
:root {
    --bg-color: rgba(0, 0, 0, 0.95);
    --container-bg: rgba(255, 255, 255, 0.85);
    --card-bg: rgba(255, 255, 255, 0.7);
    --text-primary: #333333;
    --text-secondary: #666666;
    --accent-color: #4a9eff;
    --hover-color: #5cb3ff;
    --border-radius: 20px;
    --transition: all 0.3s ease;
}

/* 页面背景 */
.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('bg.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    z-index: -1;
    overflow: hidden;
}

/* 背景遮罩层 */
.background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: -1;
}



/* 主容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    color: #ffffff;
}

/* 头部样式 */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 60px;
    background: rgba(30, 30, 30, 0.7);
    backdrop-filter: blur(20px);
    border-radius: 0 0 20px 20px;
    padding: 15px 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.logo h1 {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(45deg, var(--text-primary), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo span {
    font-weight: 300;
}

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

.nav-link {
    color: #b0b0b0;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
    text-shadow: 0 1px 2px rgba(255, 255, 255, 0.5);
}

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

.nav-link:hover {
    color: #ffffff;
}

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

/* 主要内容 */
.main-content {
    text-align: center;
}

/* 欢迎区域 */
.welcome-section {
    margin-bottom: 80px;
}

.welcome-section h2 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 20px;
    background: linear-gradient(45deg, var(--text-primary), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.welcome-section p {
    font-size: 1.2rem;
    color: #b0b0b0;
    max-width: 600px;
    margin: 0 auto;
}

/* 导航区域 */
.nav-section {
    margin-bottom: 80px;
}

.nav-section h3 {
    font-size: 2rem;
    margin-bottom: 40px;
    color: #ffffff;
}

/* 导航网格 */
.nav-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
    max-width: 1000px;
    margin: 0 auto;
}

/* 导航卡片 */
.nav-card {
    background: rgba(45, 45, 45, 0.7);
    border-radius: var(--border-radius);
    padding: 30px 20px;
    text-decoration: none;
    color: #ffffff;
    transition: var(--transition);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.nav-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(74, 158, 255, 0.1) 0%, transparent 100%);
    opacity: 0;
    transition: var(--transition);
}

.nav-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
    background: rgba(50, 50, 50, 0.85);
    border-color: rgba(74, 158, 255, 0.3);
}

.nav-card:hover::before {
    opacity: 1;
}

.nav-icon {
    font-size: 3rem;
    margin-bottom: 20px;
    transition: var(--transition);
}

.nav-card:hover .nav-icon {
    transform: scale(1.1);
}

.nav-card h4 {
    font-size: 1.2rem;
    font-weight: 600;
}

/* 特性区域 */
.features-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.feature {
    background: rgba(45, 45, 45, 0.7);
    padding: 30px;
    border-radius: var(--border-radius);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: var(--transition);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.feature:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.feature h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: #ffffff;
}

.feature p {
    color: #b0b0b0;
    line-height: 1.6;
}

/* 关于页面样式 */
.about-section {
    margin-bottom: 60px;
}

.about-content {
    background: rgba(45, 45, 45, 0.7);
    padding: 40px;
    border-radius: var(--border-radius);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 30px;
    text-align: left;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.about-content h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: #ffffff;
}

.about-content p {
    color: #b0b0b0;
    line-height: 1.8;
    margin-bottom: 15px;
}

/* 团队成员 */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px;
    margin-top: 30px;
}

.team-member {
    background: rgba(45, 45, 45, 0.6);
    padding: 30px;
    border-radius: var(--border-radius);
    text-align: center;
    transition: var(--transition);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.team-member:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
    background: rgba(55, 55, 55, 0.8);
}

.team-avatar {
    font-size: 4rem;
    margin-bottom: 15px;
}

.team-member h4 {
    font-size: 1.3rem;
    margin-bottom: 10px;
    color: #ffffff;
}

.team-member p {
    color: #b0b0b0;
    font-size: 1rem;
}

/* 联系页面样式 */
.contact-section {
    margin-bottom: 60px;
}

.contact-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    max-width: 1000px;
    margin: 0 auto;
}

.contact-form {
    background: rgba(45, 45, 45, 0.7);
    padding: 40px;
    border-radius: var(--border-radius);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    text-align: left;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.contact-form h3 {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: #ffffff;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #ffffff;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 15px;
    background: rgba(60, 60, 60, 0.9);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    color: #ffffff;
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    background: rgba(55, 55, 55, 0.8);
    box-shadow: 0 0 0 3px rgba(74, 158, 255, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: rgba(255, 255, 255, 0.5);
}

.submit-btn {
    width: 100%;
    padding: 15px;
    background: rgba(60, 60, 60, 0.9);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    color: #fff;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(74, 158, 255, 0.3);
}

.contact-info {
    background: rgba(45, 45, 45, 0.7);
    padding: 40px;
    border-radius: var(--border-radius);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    text-align: left;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.contact-info h3 {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: #ffffff;
}

.contact-details {
    margin-bottom: 30px;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 25px;
    padding-bottom: 25px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.contact-item:last-child {
    margin-bottom: 0;
    padding-bottom: 0;
    border-bottom: none;
}

.contact-icon {
    font-size: 2rem;
    margin-right: 20px;
    margin-top: 5px;
}

.contact-text h4 {
    font-size: 1.2rem;
    margin-bottom: 5px;
    color: #ffffff;
}

.contact-text p {
    color: #b0b0b0;
    line-height: 1.6;
}

.contact-note {
    background: rgba(74, 158, 255, 0.1);
    padding: 25px;
    border-radius: 8px;
    border-left: 4px solid var(--accent-color);
}

.contact-note h4 {
    font-size: 1.1rem;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.contact-note p {
    color: #b0b0b0;
    line-height: 1.6;
}

/* 页脚 */
.footer {
    text-align: center;
    padding: 30px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: #b0b0b0;
    font-size: 0.9rem;
    background: rgba(30, 30, 30, 0.6);
    backdrop-filter: blur(20px);
    box-shadow: 0 -4px 6px rgba(0, 0, 0, 0.3);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .header {
        flex-direction: column;
        gap: 20px;
        margin-bottom: 40px;
    }
    
    .nav {
        gap: 20px;
    }
    
    .welcome-section h2 {
        font-size: 2rem;
    }
    
    .welcome-section p {
        font-size: 1rem;
    }
    
    .nav-section h3 {
        font-size: 1.5rem;
    }
    
    .nav-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 20px;
    }
    
    .nav-card {
        padding: 20px 15px;
    }
    
    .nav-icon {
        font-size: 2.5rem;
        margin-bottom: 15px;
    }
    
    .features-section {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    /* 关于页面响应式 */
    .about-content {
        padding: 30px 20px;
    }
    
    .about-content h3 {
        font-size: 1.5rem;
    }
    
    .team-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 20px;
    }
    
    .team-member {
        padding: 20px;
    }
    
    .team-avatar {
        font-size: 3rem;
    }
    
    /* 联系页面响应式 */
    .contact-container {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .contact-form,
    .contact-info {
        padding: 30px 20px;
    }
    
    .contact-form h3,
    .contact-info h3 {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .welcome-section h2 {
        font-size: 1.8rem;
    }
    
    .nav-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .nav-card h4 {
        font-size: 1rem;
    }
}