/* ナビゲーションサイドバー */
#nav-sidebar { width: 120px; background: var(--panel); border-right: 1px solid #000; display: flex; flex-direction: column; padding: 20px 10px; flex-shrink: 0; align-items: center; }
.nav-title { font-size: 24px; font-weight: bold; color: var(--accent); cursor: pointer; margin-bottom: 30px; text-align: center; }
.nav-menu { display: flex; flex-direction: column; gap: 15px; width: 100%; }
.nav-link { padding: 10px; color: #ccc; text-decoration: none; text-align: center; border-radius: 4px; transition: background 0.3s; }
.nav-link:hover { background: #1e293b; color: #fff; }
.nav-link.active { background: var(--active); color: #fff; }