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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
    line-height: 1.7;
    color: #333;
    background-color: #fafafa;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 24px;
    width: 100%;
}

header {
    background-color: #fff;
    border-bottom: 1px solid #e0e0e0;
    padding: 20px 0;
    margin-bottom: 40px;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: #2c3e50;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo img {
    height: 40px;
    width: auto;
}

.tagline {
    font-size: 14px;
    color: #7f8c8d;
    margin-top: 4px;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
}

nav a {
    color: #34495e;
    text-decoration: none;
    font-size: 14px;
}

nav a:hover {
    color: #2c3e50;
    text-decoration: underline;
}

main {
    background-color: #fff;
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin-bottom: 40px;
    max-width: 100%;
    box-sizing: border-box;
    overflow-x: hidden;
}

footer {
    text-align: center;
    padding: 40px 0;
    color: #7f8c8d;
    font-size: 14px;
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
}

.footer-logo {
    display: inline-flex;
    line-height: 0;
}

.footer-logo img {
    height: 28px;
    width: auto;
}

.footer-content p {
    margin: 0;
}

h1 {
    font-size: 32px;
    margin-bottom: 20px;
    color: #2c3e50;
}

h2 {
    font-size: 24px;
    margin-top: 40px;
    margin-bottom: 20px;
    color: #34495e;
    border-bottom: 2px solid #ecf0f1;
    padding-bottom: 10px;
}

h3 {
    font-size: 20px;
    margin-top: 30px;
    margin-bottom: 15px;
    color: #34495e;
}

p {
    margin-bottom: 15px;
}

a {
    color: #3498db;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.article-list {
    list-style: none;
}

.article-item {
    padding: 20px 0;
    border-bottom: 1px solid #ecf0f1;
}

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

.article-title {
    font-size: 20px;
    margin-bottom: 8px;
}

.article-meta {
    font-size: 14px;
    color: #7f8c8d;
    margin-bottom: 10px;
}

.article-meta span {
    margin-right: 15px;
}

.tag {
    display: inline-block;
    background-color: #ecf0f1;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 12px;
    margin-right: 8px;
    color: #34495e;
}

/* ネストされたリストのスタイル */
.article-content ul,
.article-content ol {
    margin-left: 20px;
    margin-bottom: 15px;
    padding-left: 20px;
    display: block;
    list-style-type: disc;
}

.article-content ul ul,
.article-content ol ol,
.article-content ul ol,
.article-content ol ul {
    margin-top: 8px;
    margin-bottom: 8px;
    margin-left: 20px;
    padding-left: 20px;
}

.article-content li {
    margin-bottom: 8px;
    display: list-item;
}

/* 記事コンテンツの読みやすさを向上 */
.article-content {
    max-width: 800px;
    margin: 0 auto;
}

article {
    max-width: 100%;
}

.article-content li > ul,
.article-content li > ol {
    margin-top: 8px;
    margin-bottom: 8px;
}

/* ネストされたリストの視覚的なインデントを強化 */
.article-content ul ul {
    list-style-type: circle;
}

.article-content ul ul ul {
    list-style-type: square;
}

.category-link {
    display: inline-block;
    margin-right: 10px;
    margin-bottom: 10px;
    padding: 8px 16px;
    background-color: #3498db;
    color: #fff;
    border-radius: 4px;
    text-decoration: none;
    font-size: 14px;
}

.category-link:hover {
    background-color: #2980b9;
}

.category-link {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.category-link-icon {
    width: 24px;
    height: auto;
    vertical-align: middle;
}

/* トップページ（index） */
.index-hero {
    margin-bottom: 40px;
}

.index-hero-title {
    font-size: 28px;
    line-height: 1.4;
    color: #2c3e50;
    margin-bottom: 16px;
}

.index-hero-lead {
    font-size: 18px;
    color: #555;
    line-height: 1.7;
    max-width: 640px;
}

.index-intro,
.index-featured,
.index-latest,
.index-categories,
.index-tags,
.index-about {
    margin-top: 48px;
}

.index-section-lead {
    color: #555;
    font-size: 15px;
    margin-bottom: 20px;
    line-height: 1.7;
}

.index-intro-list {
    list-style: none;
    padding: 0;
    line-height: 2;
}

.index-intro-list li {
    margin-bottom: 8px;
    padding-left: 1.2em;
    position: relative;
}

.index-intro-list li::before {
    content: "・";
    position: absolute;
    left: 0;
}

.index-about-actions {
    margin-top: 20px;
    margin-bottom: 0;
}

.index-link-sep {
    margin: 0 10px;
    color: #bdc3c7;
}

.index-empty {
    color: #7f8c8d;
}

/* 記事リスト（一覧） */
.article-item {
    display: flex;
    gap: 24px;
    align-items: flex-start;
}

.article-item-image {
    flex-shrink: 0;
    min-width: 200px;
    max-width: 300px;
}

.article-item-image img {
    width: 100%;
    max-width: 300px;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.article-item-body {
    flex: 1;
    min-width: 0;
}

.article-meta-icon {
    width: 20px;
    height: auto;
    margin-right: 6px;
    vertical-align: middle;
}

.article-meta-date::before {
    content: "📅 ";
}

.article-tags {
    margin-top: 10px;
}

.article-tags .tag {
    margin-bottom: 4px;
}

.tag-icon {
    width: 18px;
    height: 18px;
    margin-right: 6px;
    vertical-align: middle;
    border-radius: 4px;
}

/* 構造タググリッド（トップ） */
.index-tags-grid .index-tag-pill {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 12px 16px;
}

/* グリッドレイアウト用のユーティリティクラス */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.grid-auto {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

/* レスポンシブデザイン */

/* タブレット (768px - 1024px) */
@media (max-width: 1024px) {
    .container {
        max-width: 100%;
        padding: 0 20px;
    }
    
    main {
        padding: 30px;
    }
    
    h1 {
        font-size: 28px;
    }
    
    h2 {
        font-size: 22px;
    }
    
    .grid-4 {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* スマートフォン (最大768px) */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    header {
        padding: 16px 0;
        margin-bottom: 24px;
    }
    
    .header-content {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }
    
    nav ul {
        flex-wrap: wrap;
        gap: 12px;
        width: 100%;
    }
    
    nav a {
        font-size: 13px;
    }
    
    .logo {
        font-size: 20px;
    }
    
    .logo img {
        height: 32px;
    }
    
    main {
        padding: 20px;
        margin-bottom: 24px;
        overflow-x: hidden;
        width: 100%;
        box-sizing: border-box;
    }
    
    body {
        overflow-x: hidden;
    }
    
    .container {
        overflow-x: hidden;
        width: 100%;
        box-sizing: border-box;
    }
    
    h1 {
        font-size: 24px;
        margin-bottom: 16px;
    }
    
    h2 {
        font-size: 20px;
        margin-top: 32px;
        margin-bottom: 16px;
    }
    
    h3 {
        font-size: 18px;
        margin-top: 24px;
        margin-bottom: 12px;
    }
    
    footer {
        padding: 24px 0;
        font-size: 12px;
    }
    
    .grid-4,
    .grid-3,
    .grid-2 {
        grid-template-columns: 1fr;
    }
    
    .grid-auto {
        grid-template-columns: 1fr;
    }
    
    .article-item {
        flex-direction: column;
    }

    .article-item-image {
        min-width: 0;
        max-width: 100%;
    }

    /* 記事サムネイルのみ幅100%。カテゴリ・タグの小アイコンは .article-meta-icon / .tag-icon のまま */
    .article-item-image img {
        width: 100% !important;
        max-width: 100% !important;
    }

    .index-hero-title {
        font-size: 22px;
    }

    .index-hero-lead {
        font-size: 16px;
    }
    
    /* カテゴリ/タグページのヘッダー画像を縦並びに */
    div[style*="display: flex"] {
        flex-direction: column !important;
        align-items: flex-start !important;
    }
    
    div[style*="display: flex"] img {
        max-width: 100% !important;
        width: 100% !important;
        margin-bottom: 16px;
    }
}

/* 大型PC (1400px以上) */
@media (min-width: 1400px) {
    .container {
        max-width: 1600px;
    }
}

/* 中型PC (1024px - 1400px) */
@media (min-width: 1024px) and (max-width: 1399px) {
    .container {
        max-width: 1200px;
    }
}

/* 管理画面用スタイル */
.admin-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 20px;
}

.admin-button {
    padding: 8px 16px;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    display: inline-block;
    text-align: center;
    font-size: 14px;
    white-space: nowrap;
}

.admin-button:hover {
    opacity: 0.9;
    text-decoration: none;
}

.admin-button-blue {
    background-color: #3498db;
}

.admin-button-green {
    background-color: #16a085;
}

.admin-button-green-alt {
    background-color: #27ae60;
}

.admin-button-orange {
    background-color: #e67e22;
}

.admin-button-purple {
    background-color: #9b59b6;
}

.admin-button-red {
    background-color: #e74c3c;
}

.admin-search-form {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    align-items: flex-end;
}

.admin-search-form > div {
    flex: 1;
    min-width: 150px;
}

.admin-search-form label {
    display: block;
    margin-bottom: 5px;
    font-size: 14px;
    font-weight: 500;
}

.admin-search-form input,
.admin-search-form select {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
    box-sizing: border-box;
}

.admin-search-form button {
    padding: 8px 16px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    white-space: nowrap;
}

.admin-search-form button:hover {
    background-color: #2980b9;
}

.admin-table-wrapper {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin: 20px 0;
    width: 100%;
    max-width: 100%;
    box-sizing: border-box;
}

.admin-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px;
}

.admin-table thead {
    background-color: #ecf0f1;
}

.admin-table th,
.admin-table td {
    padding: 10px;
    text-align: left;
    border: 1px solid #ddd;
    font-size: 14px;
}

.admin-table th {
    font-weight: 600;
    white-space: nowrap;
}

.admin-table td {
    word-break: break-word;
}

.admin-table a:not(.admin-button) {
    color: #3498db;
    text-decoration: none;
    margin-right: 10px;
}

.admin-table a:not(.admin-button):hover {
    text-decoration: underline;
}

.admin-table .admin-button {
    margin-right: 0;
}

.admin-table button:not(.admin-button) {
    padding: 4px 8px;
    background-color: #e74c3c;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
}

.admin-table button:not(.admin-button):hover {
    background-color: #c0392b;
}

/* 管理画面のモバイル対応 */
@media (max-width: 768px) {
    .admin-buttons {
        flex-direction: column;
        gap: 8px;
    }
    
    .admin-button {
        width: 100%;
        padding: 12px 16px;
        font-size: 16px;
    }
    
    .admin-search-form {
        flex-direction: column;
        align-items: stretch;
    }
    
    .admin-search-form > div {
        min-width: 100%;
    }
    
    .admin-search-form button {
        width: 100%;
        padding: 12px 16px;
        font-size: 16px;
    }
    
    .admin-table-wrapper {
        margin: 16px 0;
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    
    .admin-table {
        font-size: 12px;
        min-width: 0;
        width: 100%;
    }
    
    .admin-table th,
    .admin-table td {
        padding: 8px 6px;
    }
    
    .admin-table thead {
        display: none;
    }
    
    .admin-table tbody,
    .admin-table tr {
        display: block;
        width: 100%;
        box-sizing: border-box;
    }
    
    .admin-table tr {
        margin-bottom: 16px;
        border: 1px solid #ddd;
        border-radius: 4px;
        padding: 12px;
        background-color: #fff;
        box-shadow: 0 1px 3px rgba(0,0,0,0.1);
        width: 100%;
        max-width: 100%;
        box-sizing: border-box;
    }
    
    .admin-table td {
        display: block;
        border: none;
        padding: 8px 0;
        text-align: left;
        width: 100%;
        box-sizing: border-box;
        word-wrap: break-word;
        overflow-wrap: break-word;
    }
    
    .admin-table td:first-child {
        padding-top: 0;
        margin-bottom: 12px;
    }
    
    .admin-table td:first-child a {
        font-size: 16px;
        font-weight: 600;
        color: #2c3e50;
        word-break: break-word;
        overflow-wrap: break-word;
        display: block;
    }
    
    .admin-table td:not(:first-child) {
        border-top: 1px solid #eee;
        padding-top: 10px;
        margin-top: 10px;
    }
    
    .admin-table td:last-child {
        padding-bottom: 0;
    }
    
    .admin-table td::before {
        content: attr(data-label) ": ";
        font-weight: 600;
        display: inline-block;
        min-width: 70px;
        color: #7f8c8d;
        font-size: 13px;
    }
    
    .admin-table td:first-child::before {
        display: none;
    }
    
    .admin-table td .tag {
        display: inline-block;
        margin: 4px 4px 4px 0;
        font-size: 11px;
        word-break: break-word;
        max-width: 100%;
    }
    
    .admin-table td a:not(:first-child) {
        display: inline-block;
        margin-top: 4px;
        margin-right: 8px;
        word-break: break-word;
    }
    
    .admin-table td button,
    .admin-table td .admin-button,
    .admin-table td a.admin-button {
        margin-top: 8px;
        width: 100%;
        padding: 10px;
        font-size: 14px;
        box-sizing: border-box;
        display: block;
        text-align: center;
        color: white !important;
        text-decoration: none;
    }
    
    .admin-table td .admin-button:first-child,
    .admin-table td a.admin-button:first-child {
        margin-top: 0;
    }
    
    .admin-action-buttons {
        display: flex;
        flex-direction: column;
        gap: 8px;
        width: 100%;
        box-sizing: border-box;
    }
    
    .admin-action-buttons .admin-button-small,
    .admin-action-buttons a.admin-button-small,
    .admin-action-buttons button.admin-button-small {
        width: 100%;
        text-align: center;
        box-sizing: border-box;
        padding: 10px;
        font-size: 14px;
        display: block;
        color: white !important;
    }
    
    .admin-action-buttons .admin-button,
    .admin-action-buttons a.admin-button,
    .admin-action-buttons button.admin-button {
        margin-top: 0;
    }
}

/* 管理画面用の追加スタイル */
.admin-button-small {
    padding: 6px 12px;
    font-size: 13px;
}

.admin-button-gray {
    background-color: #95a5a6;
}

.admin-action-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.admin-dialog {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    padding: 20px;
    box-sizing: border-box;
}

.admin-dialog-content {
    background: white;
    padding: 24px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
}

.admin-dialog-buttons {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    margin-top: 20px;
}

.admin-message {
    margin-top: 20px;
    padding: 12px;
    border-radius: 4px;
    font-size: 14px;
}

.admin-message.success {
    background-color: #efe;
    color: #3c3;
}

.admin-message.error {
    background-color: #fee;
    color: #c33;
}

/* モバイル対応: ダイアログ */
@media (max-width: 768px) {
    .admin-dialog {
        padding: 16px;
    }
    
    .admin-dialog-content {
        padding: 20px;
        max-width: 100%;
    }
    
    .admin-dialog-buttons {
        flex-direction: column;
    }
    
    .admin-dialog-buttons button {
        width: 100%;
    }
    
    .admin-action-buttons {
        flex-direction: column;
        gap: 8px;
    }
    
    .admin-action-buttons .admin-button-small {
        width: 100%;
        padding: 10px;
        font-size: 14px;
    }
}