/* --- 全体のスタイル --- */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.8;
    color: #333;
    background-color: #f9f9f9;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

/* --- ヘッダー --- */
header {
    text-align: center;
    padding: 40px 0;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    color: #2c3e50;
}

header p {
    font-size: 1.2em;
    color: #7f8c8d;
}

/* --- セクション共通スタイル --- */
.section {
    background-color: #fff;
    margin-bottom: 30px;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.section h2 {
    font-size: 1.8em;
    margin-top: 0;
    padding-bottom: 10px;
    border-bottom: 2px solid #e0e0e0;
    color: #34495e;
}

/* --- ダウンロードセクション --- */
.download-section {
    text-align: center;
}

.download-buttons {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    margin-top: 20px;
    flex-wrap: wrap; /* スマホ表示で折り返す */
}

.download-buttons a img {
    height: 60px;
    transition: transform 0.2s ease;
}

.download-buttons a:hover img {
    transform: scale(1.05);
}

/* --- ヘルプセクション --- */
.faq-item {
    margin-bottom: 15px;
}

.faq-item strong {
    display: block;
    color: #2980b9;
}

/* --- 修正履歴セクション --- */
.history-item {
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid #eee;
}

.history-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.history-item h3 {
    font-size: 1.2em;
    margin: 0 0 10px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.history-item h3 .date {
    font-size: 0.8em;
    font-weight: normal;
    color: #95a5a6;
    background-color: #ecf0f1;
    padding: 3px 8px;
    border-radius: 4px;
}

.history-item ul {
    padding-left: 20px;
    margin: 0;
}

/* --- フッター --- */
footer {
    text-align: center;
    padding: 30px 0;
    color: #95a5a6;
    font-size: 0.9em;
}

footer a {
    color: #7f8c8d;
    text-decoration: none;
    margin: 0 10px;
}

footer a:hover {
    text-decoration: underline;
}