.merger-wrapper {
    max-width: 800px;
    margin: 40px auto;
    padding: 20px;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.merger-wrapper h2 {
    font-size: 28px;
    color: #333;
    text-align: center;
    margin-bottom: 20px;
    background: none;
}

.merger-wrapper p {
    text-align: center;
    color: #666;
    margin-bottom: 30px;
}

.merger-inputs {
    margin-bottom: 30px;
}

.merger-inputs input[type="file"] {
    display: none;
}

/* ファイルアップロードボタングループ */
.file-upload-buttons {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.upload-btn-group {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-bottom: 20px;
}

.merger-inputs label {
    padding: 12px 24px;
    background: #f0f2f5;
    color: #333;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s;
    font-weight: 500;
    text-align: center;
}

.merger-inputs label:hover {
    background: #e4e6e9;
}

/* マージボタンとソートボタンのグループ */
.merge-btn-group {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-bottom: 20px;
}

/* マージボタン */
#merge-button {
    background: #4834d4;
    color: white;
    padding: 12px 40px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
    font-size: 16px;
}

#merge-button:hover {
    background: #3c2ab3;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(72, 52, 212, 0.2);
}

/* ソートボタン */
#sort-button {
    background: #6c5ce7;
    color: white;
    padding: 12px 40px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
    font-size: 16px;
}

#sort-button:hover {
    background: #5b4bc4;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(108, 92, 231, 0.2);
}

/* プレビューエリア */
.merger-preview {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.merger-preview h3 {
    font-size: 18px;
    color: #333;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid #e9ecef;
}

/* ファイルリストアイテム */
.merger-list .merger-item {
    background: white;
    padding: 12px;
    border-radius: 6px;
    margin-bottom: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    transition: background-color 0.2s ease, transform 0.2s ease;
}

/* ドラッグ&ドロップ関連のスタイル */
.merger-list .merger-item.sortable-ghost {
    opacity: 0.4;
    background-color: #e0e0e0;
    transform: scale(0.98);
}

.merger-list .merger-item.sortable-chosen {
    background-color: #f0f0f0;
    transform: scale(1.02);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.drag-handle {
    cursor: move;
    padding: 0 10px;
    color: #666;
    font-size: 20px;
    user-select: none;
    display: flex;
    align-items: center;
    transition: color 0.3s ease;
}

.drag-handle:hover {
    color: #4834d4;
}

.merger-item span {
    flex-grow: 1;
    margin: 0 15px;
    font-family: monospace;
    font-size: 14px;
    color: #333;
}

/* 結合されたテキストエリア */
.merger-content {
    background: white;
    padding: 15px;
    border-radius: 6px;
    max-height: 300px;
    overflow-y: auto;
    font-family: monospace;
    white-space: pre-wrap;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

/* 操作ボタン */
.merger-buttons {
    display: flex;
    gap: 15px;
    justify-content: center;
    margin-top: 20px;
}

.merger-buttons button {
    padding: 12px 30px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
    font-size: 15px;
}

/* コピーボタン */
#copy-button {
    background: #6c5ce7;
    color: white;
}

#copy-button:hover {
    background: #5b4bc4;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(108, 92, 231, 0.2);
}

/* ダウンロードボタン */
#download-button {
    background: #20bf6b;
    color: white;
}

#download-button:hover {
    background: #1b9e5a;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(32, 191, 107, 0.2);
}

/* 削除ボタン */
.merger-item .delete-button {
    padding: 6px 12px;
    background: #dc3545;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
    min-width: 60px;
}

.merger-item .delete-button:hover {
    background: #c82333;
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(220, 53, 69, 0.2);
}

/* レスポンシブ対応 */
@media (max-width: 600px) {
    .upload-btn-group {
        flex-direction: column;
        width: 100%;
    }
    
    .merger-inputs label {
        width: 100%;
        box-sizing: border-box;
    }
    
    .merger-buttons {
        flex-direction: column;
    }
    
    .merger-buttons button {
        width: 100%;
    }
    
    #merge-button,
    #sort-button {
        width: 100%;
    }
    
    .merger-item span {
        font-size: 12px;
    }
    
    .merge-btn-group {
        flex-direction: column;
    }
}

/* ホバーエフェクトの無効化（タッチデバイス用） */
@media (hover: none) {
    .merger-inputs label:hover,
    #merge-button:hover,
    #copy-button:hover,
    #download-button:hover,
    #sort-button:hover,
    .merger-item .delete-button:hover,
    .merger-item.sortable-chosen {
        transform: none;
        box-shadow: none;
    }
}