/* リセット & ベーススタイル */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #333;
    min-height: 100vh;
}

/* ヘッダー */
header {
    background: rgba(255, 255, 255, 0.95);
    padding: 1.5rem 1rem;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

header h1 {
    font-size: 2rem;
    color: #667eea;
    margin-bottom: 0.5rem;
}

header p {
    color: #666;
    font-size: 1rem;
}

/* コンテナ */
.container {
    display: flex;
    max-width: 1400px;
    margin: 1rem auto;
    gap: 1rem;
    padding: 0 0.5rem;
}

/* 作品リスト */
.artwork-list {
    flex: 0 0 300px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    height: fit-content;
}

.artwork-list h2 {
    color: #667eea;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

#artworkMenu {
    list-style: none;
}

#artworkMenu li {
    padding: 0.8rem 1rem;
    margin-bottom: 0.5rem;
    background: #f8f9fa;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    border-left: 4px solid transparent;
}

#artworkMenu li:hover {
    background: #e9ecef;
    border-left-color: #667eea;
    transform: translateX(5px);
}

#artworkMenu li.active {
    background: #667eea;
    color: white;
    border-left-color: #764ba2;
    font-weight: bold;
}

#artworkMenu li.coming-soon {
    opacity: 0.6;
    font-style: italic;
}

/* 作品表示エリア */
.artwork-display {
    flex: 1;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    position: relative;
}

/* メニューに戻るボタン */
.back-to-menu-btn {
    display: none;
    position: sticky;
    top: 0.5rem;
    left: 0;
    margin-bottom: 1rem;
    padding: 0.6rem 1.2rem;
    background: #667eea;
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    z-index: 10;
}

.back-to-menu-btn:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
}

.back-to-menu-btn:active {
    transform: translateY(0);
}

.artwork-info {
    margin-bottom: 1.5rem;
}

.artwork-info h2 {
    color: #667eea;
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.artwork-info p {
    color: #666;
    font-size: 1.1rem;
    line-height: 1.6;
}

#canvasContainer {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 400px;
    background: #f8f9fa;
    border-radius: 8px;
    padding: 0.5rem;
    overflow: hidden;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .container {
        flex-direction: column;
        margin: 0.5rem auto;
        gap: 1rem;
    }
    
    .artwork-list {
        flex: 1;
        padding: 1rem;
    }
    
    .artwork-display {
        padding: 1rem;
    }
    
    .artwork-info h2 {
        font-size: 1.5rem;
    }
    
    .artwork-info p {
        font-size: 0.95rem;
    }
}

@media (max-width: 480px) {
    header {
        padding: 1rem 0.5rem;
    }
    
    header h1 {
        font-size: 1.5rem;
    }
    
    header p {
        font-size: 0.9rem;
    }
    
    .container {
        padding: 0 0.25rem;
        margin: 0.5rem auto;
    }
    
    .artwork-list {
        padding: 0.75rem;
        border-radius: 8px;
    }
    
    .artwork-list h2 {
        font-size: 1.2rem;
    }
    
    #artworkMenu li {
        padding: 0.6rem 0.8rem;
        font-size: 0.9rem;
    }
    
    .artwork-display {
        padding: 0.75rem;
        border-radius: 8px;
    }
    
    .artwork-info {
        margin-bottom: 1rem;
    }
    
    .artwork-info h2 {
        font-size: 1.3rem;
    }
    
    .artwork-info p {
        font-size: 0.85rem;
        line-height: 1.5;
    }
    
    #canvasContainer {
        min-height: 300px;
        padding: 0.25rem;
        border-radius: 6px;
    }
}