/* 全局样式设置，确保页面元素的统一性和响应性 */
body {
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif; /* 使用现代无衬线字体，提升可读性 */
    color: #ffffff; /* 文字颜色设为白色，保证与多彩背景的对比 */
    background: linear-gradient(135deg, #1e3c72, #2a5298, #1e3c72, #2a5298);
    background-size: 400% 400%;
    animation: backgroundAnimation 20s ease infinite; /* 背景渐变动画 */
}

@keyframes backgroundAnimation {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(30, 60, 114, 0.8); /* 半透明背景，增强未来感 */
    display: flex;
    justify-content: space-between;
    padding: 15px 30px;
    z-index: 1000;
}

.navbar .logo {
    font-size: 24px;
    font-weight: bold;
}

.navbar ul {
    list-style: none;
    display: flex;
    gap: 20px;
}

.navbar ul li {
    position: relative;
}

.navbar ul li a {
    text-decoration: none;
    color: #ffffff;
    font-size: 16px;
    transition: color 0.3s ease;
}

.navbar ul li a:hover {
    color: #ffcc00; /* 点缀色，提升互动性 */
}

.navbar ul li ul {
    display: none;
    position: absolute;
    top: 35px;
    left: 0;
    background-color: rgba(46, 84, 160, 0.9);
    list-style: none;
    padding: 10px 0;
    border-radius: 4px;
}

.navbar ul li:hover ul {
    display: block;
}

.navbar ul li ul li {
    padding: 8px 20px;
}

.navbar ul li ul li a:hover {
    color: #ffffff;
    background-color: rgba(255, 204, 0, 0.2);
    border-radius: 4px;
}

/* 主内容区样式 */
.container {
    padding: 100px 50px 50px 50px; /* 顶部留出导航栏空间 */
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.section-title {
    font-size: 28px;
    color: #ffcc00; /* 点缀色，突出标题 */
    border-bottom: 2px solid #ffffff;
    display: inline-block;
    padding-bottom: 10px;
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.card {
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: 20px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.card img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    margin-bottom: 15px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card img:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 8px rgba(255, 204, 0, 0.5);
}

/* 文章样式 */
article {
    background-color: rgba(255, 255, 255, 0.05);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

article h2 {
    font-family: 'Montserrat', sans-serif;
    font-size: 24px;
    color: #ffffff;
    margin-bottom: 20px;
}

article h3 {
    font-family: 'Montserrat', sans-serif;
    font-size: 20px;
    color: #ffcc00;
    margin-top: 20px;
    margin-bottom: 10px;
}

article p {
    font-size: 16px;
    line-height: 1.6;
    color: #dddddd;
}

article pre {
    background-color: rgba(0, 0, 0, 0.7);
    padding: 15px;
    border-radius: 5px;
    overflow-x: auto;
}

article code {
    font-family: 'Courier New', Courier, monospace;
    color: #ffcc00;
}

/* 按钮样式 */
.button {
    background-color: #2a5298;
    color: #ffffff;
    padding: 12px 24px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

.button:hover {
    background-color: #1e3c72;
    transform: scale(1.05);
}

/* 表格样式 */
.table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.table thead {
    background-color: #2a5298;
    color: #ffffff;
}

.table th, .table td {
    padding: 12px 15px;
    border: 1px solid #dddddd;
    text-align: left;
}

.table tbody tr:nth-child(even) {
    background-color: rgba(42, 82, 152, 0.1);
}

.table tbody tr:hover {
    background-color: rgba(42, 82, 152, 0.2);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar ul {
        flex-direction: column;
        background-color: rgba(30, 60, 114, 0.9);
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        display: none;
    }
    
    .navbar ul.active {
        display: flex;
    }
    
    .navbar .menu-toggle {
        display: block;
        cursor: pointer;
        font-size: 24px;
    }
    
    .container {
        padding: 100px 20px 20px 20px;
    }
}

/* 动画与过渡效果 */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 1s forwards;
}

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

/* 折叠区域样式 */
.collapsible {
    background-color: rgba(42, 82, 152, 0.8);
    color: #ffffff;
    cursor: pointer;
    padding: 10px 20px;
    width: 100%;
    border: none;
    text-align: left;
    outline: none;
    font-size: 16px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

.collapsible:hover {
    background-color: #2a5298;
}

.content {
    padding: 0 20px;
    display: none;
    background-color: rgba(30, 60, 114, 0.7);
    overflow: hidden;
    border-radius: 5px;
}