/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
}

body {
    color: #fff;
    line-height: 1.6;
    overflow-x: hidden;
}

/* 背景样式 */
.background-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
}

.background-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: url('https://img0.baidu.com/it/u=3367595999,2703416052&fm=253&fmt=auto&app=138&f=JPEG?w=750&h=500');
    background-size: cover;
    background-position: center;
    filter: brightness(0.7);
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(10, 50, 80, 0.7) 0%, rgba(20, 100, 120, 0.6) 100%);
}

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

/* 头部样式 */
header {
    padding: 30px 0;
    text-align: center;
    animation: fadeInDown 1s ease-out;
}

.logo {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.5);
    background: linear-gradient(90deg, #4facfe 0%, #00f2fe 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tagline {
    font-size: 1.4rem;
    font-weight: 300;
    margin-bottom: 20px;
    color: #e0f7fa;
}

.subtitle {
    font-size: 1.1rem;
    max-width: 800px;
    margin: 0 auto 30px;
    color: #b2ebf2;
}

/* 导航卡片区域 */
.nav-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    margin: 40px 0;
}

.nav-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 15px;
    padding: 25px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

.nav-card:hover {
    transform: translateY(-10px);
    background: rgba(255, 255, 255, 0.15);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 15px;
    color: #4facfe;
}

.card-title {
    font-size: 1.4rem;
    margin-bottom: 15px;
    font-weight: 600;
}

.card-desc {
    font-size: 0.95rem;
    color: #e0f7fa;
    margin-bottom: 20px;
}

.card-btn {
    display: inline-block;
    padding: 10px 20px;
    background: rgba(79, 172, 254, 0.8);
    color: white;
    text-decoration: none;
    border-radius: 30px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.card-btn:hover {
    background: rgba(79, 172, 254, 1);
    transform: scale(1.05);
}

/* 快速事实区域 */
.quick-facts {
    background: rgba(0, 40, 70, 0.6);
    border-radius: 15px;
    padding: 30px;
    margin: 50px 0;
    text-align: center;
    backdrop-filter: blur(5px);
}

.section-title {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: #80deea;
}

.facts-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.fact-item {
    padding: 20px;
}

.fact-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: #4facfe;
    margin-bottom: 10px;
}

.fact-text {
    font-size: 1rem;
    color: #e0f7fa;
}

/* 页脚 */
footer {
    text-align: center;
    padding: 30px 0;
    margin-top: 50px;
    font-size: 0.9rem;
    color: #b2ebf2;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

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

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

.fade-in {
    animation: fadeInUp 1s ease-out;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .logo {
        font-size: 2.2rem;
    }
    
    .tagline {
        font-size: 1.2rem;
    }
    
    .nav-cards {
        grid-template-columns: 1fr;
    }
    
    .facts-container {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.8rem;
    }
    
    .facts-container {
        grid-template-columns: 1fr;
    }
}