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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", "Yu Gothic", YuGothic, "ヒラギノ角ゴ ProN W3", Hiragino Kaku Gothic ProN, Arial, "メイリオ", Meiryo, sans-serif;
    line-height: 1.7;
    color: #333;
    background-color: #f8f9fa;
}

/* ヘッダー */
header {
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.site-title {
    font-size: 1.5rem;
    font-weight: bold;
    color: #333;
    text-decoration: none;
    transition: color 0.3s;
}

.site-title:hover {
    color: #0066cc;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

nav a {
    color: #666;
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.3s;
    position: relative;
}

nav a:hover {
    color: #0066cc;
}

nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #0066cc;
    transition: width 0.3s;
}

nav a:hover::after {
    width: 100%;
}

/* メインコンテンツ */
.container {
    max-width: 800px;
    margin: 3rem auto;
    padding: 0 2rem;
}

/* ヒーローセクション */
.hero {
    text-align: center;
    padding: 4rem 0;
    background: linear-gradient(135deg, #FFD93D 0%, #6BCF9C 100%);
    color: white;
    border-radius: 15px;
    margin-bottom: 3rem;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    animation: fadeInUp 0.8s ease-out;
}

.hero p {
    font-size: 1.1rem;
    opacity: 0.95;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}

/* 記事カード */
.article-card {
    background: #fff;
    border-radius: 10px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.15);
}

.article-date {
    color: #999;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.article-title {
    font-size: 1.5rem;
    color: #333;
    margin-bottom: 1rem;
    text-decoration: none;
    display: block;
    transition: color 0.3s;
}

.article-title:hover {
    color: #0066cc;
}

.article-excerpt {
    color: #666;
    line-height: 1.8;
    margin-bottom: 1rem;
}

.article-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.tag {
    background-color: #f0f4f8;
    color: #666;
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.85rem;
    transition: background-color 0.3s, color 0.3s;
}

.tag:hover {
    background-color: #6BCF9C;
    color: white;
}

.read-more {
    color: #0066cc;
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: gap 0.3s;
}

.read-more:hover {
    gap: 1rem;
}

.read-more::after {
    content: '→';
    transition: transform 0.3s;
}

/* サイドバー */
.content-wrapper {
    display: grid;
    grid-template-columns: 1fr;
    gap: 3rem;
}

@media (min-width: 1024px) {
    .container {
        max-width: 1200px;
    }
    
    .content-wrapper {
        grid-template-columns: 2fr 1fr;
    }
}

.sidebar {
    padding: 0;
}

.sidebar-widget {
    background: white;
    border-radius: 10px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
}

.sidebar-widget h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #f0f4f8;
}

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

.sidebar-widget li {
    margin-bottom: 0.5rem;
}

.sidebar-widget a {
    color: #666;
    text-decoration: none;
    transition: color 0.3s;
}

.sidebar-widget a:hover {
    color: #0066cc;
}

/* プロフィール */
.profile {
    text-align: center;
}

.profile-img {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    margin: 0 auto 1rem;
    overflow: hidden;
    border: 3px solid #6BCF9C;
}

.profile-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* フッター */
footer {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 3rem 0;
    margin-top: 5rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 2rem;
}

.social-links a {
    color: white;
    font-size: 1.5rem;
    transition: transform 0.3s, color 0.3s;
}

.social-links a:hover {
    transform: translateY(-3px);
    color: #6BCF9C;
}

/* アニメーション */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* モバイル対応 */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        gap: 1rem;
    }

    nav ul {
        gap: 1rem;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .article-card {
        padding: 1.5rem;
    }
}

/* ダークモード対応ボタン */
.theme-toggle {
    background: none;
    border: 2px solid #666;
    border-radius: 20px;
    padding: 0.5rem 1rem;
    cursor: pointer;
    color: #666;
    transition: all 0.3s;
}

.theme-toggle:hover {
    border-color: #0066cc;
    color: #0066cc;
}

/* ページネーション */
.pagination {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 3rem;
}

.pagination a, .pagination span {
    padding: 0.5rem 1rem;
    background: white;
    border-radius: 5px;
    text-decoration: none;
    color: #666;
    transition: all 0.3s;
    box-shadow: 0 2px 5px rgba(0,0,0,0.08);
}

.pagination a:hover {
    background: #6BCF9C;
    color: white;
    transform: translateY(-2px);
}

.pagination .current {
    background: #6BCF9C;
    color: white;
}