/* リセットとベース */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

/* ヘッダー */
.header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    text-decoration: none;
    color: white;
}

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
}

.nav-menu a:hover {
    opacity: 0.8;
}

/* メインコンテンツ */
.main-content {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
}

/* 記事一覧 */
.post-list {
    display: grid;
    gap: 2rem;
}

.post-card {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    padding: 2rem;
    transition: transform 0.3s, box-shadow 0.3s;
}

.post-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

.post-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.post-meta {
    color: #7f8c8d;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.post-excerpt {
    color: #555;
    line-height: 1.8;
    margin-bottom: 1rem;
}

.post-tags {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.tag {
    background: #e3f2fd;
    color: #1976d2;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
}

/* 記事詳細 */
.post-detail {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    padding: 3rem;
    margin-bottom: 2rem;
}

.post-detail .post-title {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: #2c3e50;
}

.post-content {
    font-size: 1.1rem;
    line-height: 1.8;
    color: #444;
}

.post-content h1,
.post-content h2,
.post-content h3,
.post-content h4,
.post-content h5,
.post-content h6 {
    margin: 2rem 0 1rem;
    color: #2c3e50;
}

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

.post-content ul,
.post-content ol {
    margin-left: 2rem;
    margin-bottom: 1.5rem;
}

.post-content blockquote {
    border-left: 4px solid #3498db;
    padding-left: 1.5rem;
    margin: 1.5rem 0;
    font-style: italic;
    color: #555;
}

.post-content code {
    background: #f8f9fa;
    padding: 0.2rem 0.4rem;
    border-radius: 3px;
    font-family: 'Courier New', monospace;
}

.post-content pre {
    background: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1.5rem 0;
}

/* コメント */
.comments-section {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    padding: 2rem;
}

.comment-form {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 8px;
    margin-bottom: 2rem;
}

.comment-form h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #555;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #e1e8ed;
    border-radius: 5px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #3498db;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.comment-item {
    border-bottom: 1px solid #e1e8ed;
    padding: 1.5rem 0;
}

.comment-item:last-child {
    border-bottom: none;
}

.comment-author {
    font-weight: bold;
    color: #2c3e50;
    margin-bottom: 0.5rem;
}

.comment-date {
    color: #7f8c8d;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.comment-content {
    color: #555;
    line-height: 1.6;
}

/* ボタン */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    border: none;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
}

.btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

.btn-secondary {
    background: #95a5a6;
}

.btn-secondary:hover {
    background: #7f8c8d;
}

.btn-danger {
    background: #e74c3c;
}

.btn-danger:hover {
    background: #c0392b;
}

.btn-success {
    background: #27ae60;
}

.btn-success:hover {
    background: #229954;
}

/* ページネーション */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    margin: 2rem 0;
}

.pagination button {
    padding: 0.5rem 1rem;
    border: 2px solid #e1e8ed;
    background: white;
    color: #555;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
}

.pagination button:hover {
    background: #f8f9fa;
}

.pagination button.active {
    background: #3498db;
    color: white;
    border-color: #3498db;
}

.pagination button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* 管理画面 */
.admin-header {
    background: #2c3e50;
    color: white;
    padding: 1rem 0;
}

.admin-sidebar {
    background: #34495e;
    color: white;
    padding: 2rem 0;
    position: fixed;
    left: 0;
    top: 0;
    height: 100vh;
    width: 250px;
    overflow-y: auto;
}

.admin-main {
    margin-left: 250px;
    padding: 2rem;
}

.admin-nav {
    list-style: none;
    padding: 0;
}

.admin-nav li {
    margin-bottom: 0.5rem;
}

.admin-nav a {
    display: block;
    color: white;
    text-decoration: none;
    padding: 1rem 2rem;
    transition: background-color 0.3s;
}

.admin-nav a:hover,
.admin-nav a.active {
    background: #2c3e50;
}

.admin-card {
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    padding: 2rem;
    margin-bottom: 2rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    text-align: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: bold;
    color: #3498db;
    margin-bottom: 0.5rem;
}

.stat-label {
    color: #7f8c8d;
    font-size: 1.1rem;
}

/* データテーブル */
.data-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.data-table th,
.data-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid #e1e8ed;
}

.data-table th {
    background: #f8f9fa;
    font-weight: 600;
    color: #2c3e50;
}

.data-table tr:hover {
    background: #f8f9fa;
}

/* フォーム */
.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
    margin-bottom: 1rem;
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

/* アラート */
.alert {
    padding: 1rem;
    border-radius: 5px;
    margin-bottom: 1rem;
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-info {
    background: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* ローディング */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* レスポンシブ */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-menu {
        flex-direction: column;
        gap: 1rem;
    }
    
    .main-content {
        padding: 0 1rem;
    }
    
    .post-card,
    .post-detail,
    .comments-section {
        padding: 1.5rem;
    }
    
    .post-detail .post-title {
        font-size: 2rem;
    }
    
    .admin-sidebar {
        position: relative;
        width: 100%;
        height: auto;
    }
    
    .admin-main {
        margin-left: 0;
        padding: 1rem;
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
}

/* ユーティリティ */
.hidden {
    display: none !important;
}

.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.p-0 { padding: 0; }
.p-1 { padding: 0.5rem; }
.p-2 { padding: 1rem; }
.p-3 { padding: 1.5rem; }
.p-4 { padding: 2rem; }