/* 基础样式定义 */
:root {
    --main-color: #0074D9; /* 深蓝色 */
    --accent-color: #FFA500; /* 橙色 */
    --secondary-color: #8A2BE2; /* 紫色 */
    --background-color: #F5F5F5; /* 浅灰色背景 */
    --font-title: 'Roboto', sans-serif;
    --font-body: 'Open Sans', sans-serif;
}

body {
    margin: 0;
    font-family: var(--font-body);
    background: linear-gradient(135deg, #E6F7FF, #FFFFFF);
    color: #333;
    line-height: 1.6;
    padding: 20px;
    overflow-x: hidden;
}

h1, h2, h3, h4 {
    font-family: var(--font-title);
    color: var(--main-color);
    text-align: center;
    margin-bottom: 20px;
}

h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, var(--main-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    padding: 20px;
}

.card {
    background: #FFF;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    overflow: hidden;
    position: relative;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 8px 12px rgba(0, 0, 0, 0.2);
}

.card img {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
}

.card-content {
    padding: 15px;
    text-align: center;
}

.card-title {
    font-size: 1.2rem;
    font-weight: bold;
    margin-bottom: 10px;
    color: var(--main-color);
}

.card-description {
    font-size: 0.9rem;
    color: #555;
    margin-bottom: 10px;
}

.card-tags {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.card-tag {
    background: var(--accent-color);
    color: #FFF;
    font-size: 0.8rem;
    padding: 5px 10px;
    border-radius: 20px;
}

.article-container {
    background: #FFF;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    padding: 20px;
    margin-top: 40px;
}

.article-container h2 {
    font-size: 2rem;
    margin-bottom: 20px;
}

.article-container pre {
    background: #F5F5F5;
    padding: 15px;
    border-radius: 8px;
    overflow-x: auto;
    font-size: 0.9rem;
    color: #333;
}

.article-container table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
}

.article-container th, .article-container td {
    border: 1px solid #DDD;
    padding: 10px;
    text-align: left;
}

.article-container th {
    background: var(--main-color);
    color: #FFF;
}

@media (max-width: 768px) {
    h1 {
        font-size: 2rem;
    }

    .container {
        grid-template-columns: 1fr;
    }

    .card {
        margin-bottom: 20px;
    }
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

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