/* ニュース記事共通スタイル */
:root {
    --primary-color: #1a73e8;
    --secondary-color: #34a853;
    --text-color: #202124;
    --text-secondary: #5f6368;
    --border-color: #dadce0;
    --bg-light: #f8f9fa;
    --shadow: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    --shadow-hover: 0 4px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.7;
    color: var(--text-color);
    background-color: #fff;
}
/* Responsive media handling */
.article-image,
.news-article-image,
.news-card img,
.news-card-image img,
.article-hero-image img,
.featured-image img,
.article-hero img {
    max-width: 100%;
    height: auto;
    display: block;
}


/* ヘッダー */
.site-header {
    background-color: #fff;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.site-header .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.site-nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

.site-nav ul li {
    white-space: nowrap;
}

.site-nav a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

.site-nav a:hover {
    color: var(--primary-color);
}

/* 記事コンテナ */
.article-container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: 3rem;
}

/* メインコンテンツ */
.article-main {
    background: #fff;
}

.article-header {
    margin-bottom: 2rem;
}

.article-category {
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: 0.25rem 0.75rem;
    border-radius: 4px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1rem;
}

.article-title {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.article-meta {
    display: flex;
    gap: 1.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

.article-meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.article-featured-image,
.featured-image {
    width: 100%;
    max-height: 350px;
    height: auto;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
}

.article-content {
    font-size: 1.1rem;
    line-height: 1.8;
}

.article-content h2 {
    font-size: 1.75rem;
    font-weight: 700;
    margin: 2.5rem 0 1rem;
    color: var(--text-color);
    border-left: 4px solid var(--primary-color);
    padding-left: 1rem;
}

.article-content h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin: 2rem 0 1rem;
    color: var(--text-color);
}

.article-content p {
    margin-bottom: 1.5rem;
}

.article-content ul,
.article-content ol {
    margin: 1.5rem 0;
    padding-left: 2rem;
}

.article-content li {
    margin-bottom: 0.75rem;
}

.article-content strong {
    font-weight: 600;
    color: var(--text-color);
}

/* サイドバー */
.article-sidebar {
    position: sticky;
    top: 100px;
    height: fit-content;
}

.sidebar-widget {
    background-color: var(--bg-light);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.sidebar-widget-title {
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.sidebar-toc ul {
    list-style: none;
}

.sidebar-toc li {
    margin-bottom: 0.75rem;
}

.sidebar-toc a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s;
}

.sidebar-toc a:hover {
    color: var(--primary-color);
}

/* ニュース一覧ページ */
.news-index-header {
    text-align: center;
    padding: 3rem 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: #fff;
    margin-bottom: 3rem;
}

.news-index-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.news-grid {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem 3rem;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
}

.news-card {
    background: #fff;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
    text-decoration: none;
    color: inherit;
    display: block;
}

.news-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-hover);
}

.news-card-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.news-card-content {
    padding: 1.5rem;
}

.news-card-category {
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: 0.75rem;
}

.news-card-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--text-color);
    line-height: 1.4;
}

.news-card-excerpt {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.news-card-date {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* フッター */
.site-footer {
    background-color: #f8f9fa;
    padding: 2rem 0;
    margin-top: 4rem;
    border-top: 1px solid var(--border-color);
}

.site-footer .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    text-align: center;
    color: var(--text-secondary);
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .article-container {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .article-sidebar {
        position: static;
        order: -1;
    }

    .article-title {
        font-size: 1.75rem;
    }

    .site-header .container {
        flex-direction: column;
        gap: 1rem;
    }

    .site-nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1rem;
    }

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