body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f4f7f6;
    color: #333;
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100vh;
}

.container {
    background-color: #ffffff;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 800px;
    box-sizing: border-box;
}

h1, h2 {
    color: #007bff;
    text-align: center;
    margin-bottom: 25px;
}

form {
    display: flex;
    flex-direction: column;
    gap: 15px;
    margin-bottom: 30px;
    border: 1px solid #e0e0e0;
    padding: 20px;
    border-radius: 8px;
    background-color: #fdfdfd;
}

.form-group {
    margin-bottom: 10px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: #555;
}

input[type="url"],
input[type="file"] {
    width: calc(100% - 20px);
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 16px;
    box-sizing: border-box;
}

input[type="file"] {
    padding: 5px; /* ファイル選択ボタンの見た目を調整 */
}

small {
    display: block;
    margin-top: 5px;
    color: #666;
    font-size: 0.85em;
}

button {
    background-color: #28a745;
    color: white;
    padding: 12px 20px;
    border: none;
    border-radius: 5px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    width: 100%;
    box-sizing: border-box;
}

button:hover {
    background-color: #218838;
}

button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
}

.message {
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    text-align: center;
    font-weight: bold;
}

.message.success {
    background-color: #d4edda;
    color: #155724;
    border-color: #c3e6cb;
}

.message.error {
    background-color: #f8d7da;
    color: #721c24;
    border-color: #f5c6cb;
}

#progressArea {
    margin-top: 20px;
    padding: 15px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    background-color: #fdfdfd;
}

.progress-item {
    margin-bottom: 15px;
    padding: 10px;
    border: 1px solid #dcdcdc;
    border-radius: 5px;
    background-color: #f0f0f0;
}

.progress-bar-container {
    width: 100%;
    background-color: #e0e0e0;
    border-radius: 5px;
    margin-top: 10px;
    overflow: hidden;
}

.progress-bar {
    width: 0%;
    height: 20px;
    background-color: #007bff;
    border-radius: 5px;
    text-align: center;
    color: white;
    line-height: 20px;
    transition: width 0.3s ease;
}

.progress-text {
    font-size: 0.9em;
    color: #555;
    margin-top: 5px;
}

.progress-item.error {
    background-color: #ffebeb;
    border-color: #f0c2c2;
    color: #cc0000;
}

.progress-item.completed {
    background-color: #e6ffe6;
    border-color: #c2f0c2;
    color: #008000;
}

#downloadedFilesArea {
    margin-top: 30px;
    padding: 15px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    background-color: #fdfdfd;
}

#downloadedFileList {
    list-style: none;
    padding: 0;
}

.downloaded-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
    border-bottom: 1px solid #eee;
}

.downloaded-item:last-child {
    border-bottom: none;
}

.downloaded-item a {
    color: #007bff;
    text-decoration: none;
    font-weight: bold;
}

.downloaded-item a:hover {
    text-decoration: underline;
}

.delete-button {
    background-color: #dc3545;
    color: white;
    padding: 8px 12px;
    border-radius: 5px;
    font-size: 14px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    width: auto; /* ボタンの幅をコンテンツに合わせる */
}

.delete-button:hover {
    background-color: #c82333;
}

.expired .expired-label {
    background-color: #ffc107; /* warning yellow */
    color: #333;
    padding: 3px 6px;
    border-radius: 4px;
    font-size: 0.75em;
    margin-left: 10px;
    font-weight: normal;
}