/* レイアウト - 左メニューとコンテナ */
/* テーマ: 論文風ライトテーマ */

/* 全体コンテナ */
.container-with-sidebar {
    display: flex;
    max-width: 1400px;
    margin: 0 auto;
    gap: 2rem;
}

/* 左サイドバーメニュー */
.sidebar-menu {
    width: 280px;
    flex-shrink: 0;
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    display: flex;
    flex-direction: column;
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border-primary);
    z-index: 1000;
    will-change: transform;
}

.sidebar-header {
    padding: 1.5rem 1rem 1rem;
    border-bottom: 1px solid var(--border-primary);
    flex-shrink: 0;
    background: var(--bg-secondary);
}

.sidebar-title {
    font-family: "Noto Serif JP", "Times New Roman", serif;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    display: block;
}

.sidebar-title:hover {
    text-decoration: underline;
}

/* スクロール可能なナビゲーション領域 */
.sidebar-nav-wrapper {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
}

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

.sidebar-nav > li {
    margin-bottom: 0.3rem;
}

/* トップページリンク */
.sidebar-nav .nav-top > a {
    display: block;
    padding: 0.5rem 0.75rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
}

.sidebar-nav .nav-top.current > a {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.sidebar-nav .nav-top > a:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

/* 章リンク */
.sidebar-nav .nav-chapter {
    margin-top: 0.5rem;
}

.sidebar-nav .nav-chapter > .chapter-link {
    display: block;
    padding: 0.5rem 0.75rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.85rem;
}

.sidebar-nav .nav-chapter > .chapter-link:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

/* 現在の章 */
.sidebar-nav .nav-chapter.current-chapter > .chapter-link {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    font-weight: 700;
}

/* 章内セクション */
.sidebar-nav .chapter-sections {
    list-style: none;
    padding: 0;
    margin: 0.3rem 0 0.5rem 1rem;
}

.sidebar-nav .chapter-sections > li {
    margin-bottom: 0.2rem;
}

.sidebar-nav .chapter-sections > li > a {
    display: block;
    padding: 0.35rem 0.75rem;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.8rem;
    font-weight: 500;
}

.sidebar-nav .chapter-sections > li > a:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
}

.sidebar-nav .chapter-sections > li > a.active {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    font-weight: 600;
}

/* サブセクション */
.sidebar-nav .section-subs {
    list-style: none;
    padding: 0;
    margin: 0.2rem 0 0.3rem 1rem;
}

.sidebar-nav .section-subs li {
    margin-bottom: 0.1rem;
}

.sidebar-nav .section-subs a {
    display: block;
    padding: 0.25rem 0.5rem;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.75rem;
    font-weight: normal;
}

.sidebar-nav .section-subs a:hover {
    color: var(--text-secondary);
}

.sidebar-nav .section-subs a.active {
    color: var(--text-primary);
    font-weight: 500;
}

/* 外部リンク（hatohato.jpトップ） */
.sidebar-nav .nav-external {
    margin-top: 1.5rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-primary);
}

.sidebar-nav .nav-external > a {
    display: block;
    padding: 0.5rem 0.75rem;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.85rem;
}

.sidebar-nav .nav-external > a:hover {
    color: var(--text-primary);
    text-decoration: underline;
}

/* ====== 旧スタイル互換（submenu） ====== */
.sidebar-nav .submenu {
    list-style: none;
    padding: 0;
    margin: 0.3rem 0 0.5rem 1rem;
}

.sidebar-nav .submenu li {
    margin-bottom: 0.3rem;
}

.sidebar-nav .submenu a {
    display: block;
    padding: 0.4rem 0.75rem;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.85rem;
    font-weight: normal;
}

.sidebar-nav .submenu a:hover {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
}

.sidebar-nav .submenu a.active {
    background-color: transparent;
    color: var(--text-primary);
    font-weight: 500;
}

/* メインコンテンツエリア */
.main-content {
    margin-left: 300px;
    padding: 2rem 3rem;
    flex: 1;
    min-width: 0;
    background-color: var(--bg-primary);
}

/* セクション間の区切り */
section {
    padding-bottom: 2rem;
    margin-bottom: 1rem;
}

/* ヘッダー部分 */
header {
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border-primary);
}

/* サイドバー: ブックマークリンク */
.sidebar-nav .nav-bookmark {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-secondary);
}

.sidebar-nav .nav-bookmark a,
.sidebar-nav .nav-review a {
    display: block;
    padding: 0.5rem 0.75rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.85rem;
}

.sidebar-nav .nav-bookmark a:hover,
.sidebar-nav .nav-review a:hover {
    color: var(--accent-primary);
}

.sidebar-nav .nav-bookmark.current a,
.sidebar-nav .nav-review.current a {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}