/* リセットと基本設定 */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}

a {
    color: #e67e22;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* レイアウト */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ヘッダー */
header {
    background-color: #ffffff;
    padding: 40px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    margin-bottom: 40px;
}

.header-container {
    display: flex;
    align-items: center;
    gap: 20px;
}

.app-icon {
    width: 80px;
    height: 80px;
    border-radius: 18px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.header-text h1 {
    font-size: 2rem;
    color: #2c3e50;
    margin-bottom: 5px;
}

.header-text p {
    color: #7f8c8d;
    font-size: 1.1rem;
}

/* リンクスタイル */
a.header-link {
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 20px;
    color: inherit;
}

.button {
    display: inline-block;
    padding: 10px 20px;
    background-color: #e67e22;
    color: white;
    border-radius: 5px;
    text-decoration: none;
    transition: background-color 0.3s;
}

.button:hover {
    background-color: #d35400;
    text-decoration: none;
}

/* メインコンテンツ */
section {
    background: #fff;
    padding: 30px;
    border-radius: 12px;
    margin-bottom: 30px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.03);
}

h2 {
    font-size: 1.5rem;
    color: #2c3e50;
    border-bottom: 2px solid #ecf0f1;
    padding-bottom: 10px;
    margin-bottom: 20px;
}

h3 {
    font-size: 1.2rem;
    color: #34495e;
    margin-top: 25px;
    margin-bottom: 10px;
}

p {
    margin-bottom: 15px;
}

ul, ol {
    margin-bottom: 15px;
    padding-left: 25px;
}

li {
    margin-bottom: 8px;
}

/* ルールセクション */
.rules li strong {
    color: #e67e22;
}

/* お問い合わせ */
.email-address {
    font-size: 1.1rem;
    font-weight: bold;
    background-color: #f0f4f8;
    padding: 15px;
    border-radius: 8px;
    text-align: center;
    margin-top: 15px;
}

/* フッター */
footer {
    text-align: center;
    padding: 40px 0;
    color: #95a5a6;
    font-size: 0.9rem;
}

/* レスポンシブ対応 */
@media (max-width: 600px) {
    .header-container {
        flex-direction: column;
        text-align: center;
    }

    .header-text h1 {
        font-size: 1.8rem;
    }

    section {
        padding: 20px;
    }
}