:root {
    --primary-color: #333;
    --secondary-color: #0056b3;
    --background-color: #f4f4f4;
    --text-color: #333;
    --header-bg: #fff;
    --footer-bg: #333;
    --footer-text: #fff;
    --link-color: #0056b3;
    --link-hover-color: #003d82;
    --border-color: #ddd;
    --container-width: 960px;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
    font-size: 16px;
    line-height: 1.6;
}

body {
    margin: 0;
    color: var(--text-color);
    background-color: var(--background-color);
}

.container {
    max-width: var(--container-width);
    margin: auto;
    overflow: auto;
    padding: 0 20px;
}

/* Header */
.site-header {
    background: var(--header-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    text-decoration: none;
    color: var(--primary-color);
    font-size: 1.8rem;
    font-weight: bold;
}

.main-nav ul {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
}

.main-nav li {
    margin-left: 20px;
}

.main-nav a {
    text-decoration: none;
    color: var(--primary-color);
    font-weight: 500;
}

.main-nav a:hover, .main-nav a.active {
    color: var(--secondary-color);
}

/* Main Content */
main {
    padding: 2rem 0;
}

h1, h2, h3 {
    line-height: 1.3;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }

a {
    color: var(--link-color);
}

a:hover {
    color: var(--link-hover-color);
    text-decoration: underline;
}

img {
    max-width: 100%;
    height: auto;
    border-radius: 5px;
}

/* Article Grid */
.article-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.article-card {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.article-card img {
    width: 100%;
    height: 180px;
    object-fit: cover;
}

.article-card-content {
    padding: 15px;
    flex-grow: 1;
}

.article-card-content h3 {
    margin-top: 0;
}

.article-card-content h3 a {
    text-decoration: none;
    color: var(--primary-color);
}

.article-card-content p {
    font-size: 0.9rem;
    color: #666;
}

/* Article Page */
.article-header .meta-info {
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 1rem;
}

.article-body {
    font-size: 1.1rem;
}

.article-body p {
    margin-bottom: 1.5em;
}

/* Breadcrumbs */
.breadcrumbs ol {
    list-style: none;
    padding: 0;
    margin: 0 0 1rem 0;
}

.breadcrumbs li {
    display: inline;
    font-size: 0.9rem;
}

.breadcrumbs li+li:before {
    content: '>';
    padding: 0 8px;
    color: #666;
}

.breadcrumbs a {
    text-decoration: none;
}

/* Tags */
.tags {
    margin-top: 2rem;
}

.tags a {
    display: inline-block;
    background-color: #e9e9e9;
    color: #333;
    padding: 5px 10px;
    margin-right: 5px;
    border-radius: 3px;
    text-decoration: none;
    font-size: 0.85rem;
}

/* Related Articles */
.related-articles {
    margin-top: 3rem;
    border-top: 1px solid var(--border-color);
    padding-top: 2rem;
}

/* Footer */
.site-footer {
    background: var(--footer-bg);
    color: var(--footer-text);
    padding: 2rem 0;
    margin-top: 2rem;
    font-size: 0.9rem;
}

.footer-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-nav ul {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
}

.footer-nav li {
    margin-left: 15px;
}

.footer-nav a {
    text-decoration: none;
    color: var(--footer-text);
}

.footer-nav a:hover {
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
    }

    .main-nav ul {
        flex-direction: column;
        align-items: center;
        margin-top: 1rem;
    }

    .main-nav li {
        margin: 5px 0;
    }

    h1 { font-size: 2rem; }
    h2 { font-size: 1.7rem; }

    .footer-container {
        flex-direction: column;
    }

    .footer-copyright {
        margin-bottom: 1rem;
    }
}