/* ============================================
   固定サイドバー（HTMLサイトと同じデザイン）
============================================ */
.custom-sidebar {
    width: 20%;
    min-width: 250px;
    height: 100vh;
    background: var(--sidebar-color);
    color: rgb(28, 28, 28);
    position: fixed;
    left: 0;
    top: 0;
    overflow-y: auto;
    overflow-x: hidden;
    z-index: 1500;
    box-shadow: 4px 0 14px rgba(0, 0, 0, 0.2);
}

.custom-sidebar img {
    width: 100%;
}

.sidebar-content {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 2rem;
}

/* ロゴエリア */
.logo {
    margin-bottom: 3rem;
}

.logo h1 {
    font-size: 2rem;
    font-weight: 700;
    letter-spacing: 2px;
    margin: 0;
    padding: 0;
}

.logo a {
    display: block;
}

.logo img {
    width: 100%;
    height: auto;
}

/* ナビゲーションメニュー */
.nav-menu {
    flex-grow: 1;
}

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

.nav-menu li {
    margin-bottom: 1rem;
}

.nav-menu a {
    color: rgba(26, 26, 26, 0.8);
    text-decoration: none;
    font-size: 1.1rem;
    display: block;
    padding: 0.5rem 0;
    transition: all 0.3s ease;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: rgb(46, 46, 238);
    padding-left: 1rem;
}

/* サイドバーフッター */
.sidebar-footer {
    margin-top: auto;
    padding-top: 2rem;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

.copyright {
    font-size: 0.85rem;
    opacity: 0.7;
    margin: 0;
}

.copyright a {
    color: inherit;
    text-decoration: none;
    font-size: 0.8em;
}

.copyright a:hover {
    text-decoration: underline;
}

/* ============================================
   スマホサイズ（max-width: 767px）
============================================ */
@media screen and (max-width: 767px) {
    .custom-sidebar {
        width: 80%;
        max-width: 320px;
        height: 100vh;
        position: fixed;
        left: -100%;
        top: 0;
        transition: left 0.25s ease;
        box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
        z-index: 1100;
    }
    
    .custom-sidebar.active {
        left: 0;
    }
    
    .sidebar-content {
        padding: 1.5rem;
    }
    
    .nav-menu {
        margin: 2rem 0;
    }
    
    .nav-menu li {
        margin-bottom: 0.5rem;
    }
    
    body.menu-open {
        overflow: hidden;
    }
}