/* --- 全体設定 --- */
@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+JP:wght@700&family=Noto+Sans+JP:wght@400;700&display=swap');

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans JP', sans-serif;
    color: #333;
    background-color: #fcfaf5; /* リンク集と合わせた優しい背景色 */
    line-height: 1.7;
}

/* --- ヘッダー --- */
.stretch-header {
    background: linear-gradient(135deg, #4CAF50 0%, #2e7d32 100%); /* 健康テーマに合わせたグリーン */
    color: white;
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.stretch-header h1 {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    font-size: 2.2rem;
    margin-bottom: 5px;
}

.stretch-header .lead {
    font-size: 1.1rem;
}

/* --- 導入セクション --- */
.intro-section {
    background-color: #fff;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    padding: 3rem !important;
}

.intro-title {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    color: #2d5a27; /* 健康テーマの緑 */
    font-size: 1.8rem;
}

.main-image {
    margin-top: 2rem;
}

.main-image img {
    max-height: 350px; /* メイン画像の最大高さ */
    width: auto;
    border: 3px solid #d4af37; /* アクセントカラーの枠線 */
}

/* --- カテゴリー選択セクション --- */
.category-section .section-title {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    color: #1a2a3a;
    font-size: 1.8rem;
    position: relative;
    padding-bottom: 15px;
}

.category-section .section-title::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 70px;
    height: 3px;
    background-color: #4CAF50; /* 健康テーマの緑 */
}

.category-card {
    background-color: #fff;
    border-radius: 12px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.05);
    transition: all 0.3s ease;
    text-decoration: none;
    color: #333;
    height: 100%; /* 高さを揃える */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 1.5rem !important;
}

.category-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 18px rgba(0,0,0,0.1);
    background-color: #e8f5e9; /* ホバーで少し明るい緑 */
}

.category-card img {
    width: 80px; /* アイコン画像のサイズ調整 */
    height: 80px;
    object-fit: contain;
}

.category-card h3 {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    font-size: 1.3rem;
    color: #2e7d32; /* 濃いめの緑 */
    margin-top: 10px;
    margin-bottom: 5px;
}

.category-card p {
    font-size: 0.9rem;
    color: #555;
    margin-bottom: 0;
}

/* --- ストレッチ詳細セクション --- */
.stretch-detail-section {
    background-color: #fff;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    padding: 3rem !important;
}

.detail-section-title {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    color: #2d5a27; /* 健康テーマの緑 */
    font-size: 2rem;
    position: relative;
    padding-bottom: 15px;
    margin-bottom: 3rem !important;
}

.detail-section-title::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 4px;
    background-color: #4CAF50;
}

.section-description {
    font-size: 1.1rem;
    color: #555;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.stretch-item {
    border-bottom: 1px dashed #e0e0e0;
    padding-bottom: 2rem;
    margin-bottom: 2rem !important;
}

.stretch-item:last-child {
    border-bottom: none;
    margin-bottom: 0 !important;
}

.stretch-name {
    font-family: 'Noto Serif JP', serif;
    font-weight: bold;
    color: #2e7d32; /* 濃い緑 */
    font-size: 1.5rem;
    margin-bottom: 1.5rem !important;
}

.stretch-img {
    max-width: 100%;
    height: auto;
    max-height: 250px; /* ストレッチ画像の最大高さ */
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.stretch-points {
    padding-left: 20px;
    margin-top: 1rem;
}

.stretch-points li {
    position: relative;
    margin-bottom: 10px;
    font-size: 1.05rem;
}

.stretch-points li::before {
    content: "•";
    color: #4CAF50;
    font-weight: bold;
    display: inline-block;
    width: 1em;
    margin-left: -1em;
}

.stretch-points strong {
    color: #2e7d32;
}

/* --- カテゴリーに戻るボタン (各詳細セクション下) --- */
.back-to-top-small {
    border-color: #4CAF50 !important;
    color: #2e7d32 !important;
    font-weight: bold;
    border-radius: 50px;
    padding: 8px 20px;
    transition: all 0.3s ease;
}

.back-to-top-small:hover {
    background-color: #4CAF50 !important;
    color: white !important;
}

/* --- フッター --- */
.stretch-footer {
    background-color: #2e7d32; /* 健康テーマの緑 */
    color: white;
    padding: 20px 0;
    margin-top: 50px;
}

/* --- 上に戻るボタン (右下固定) --- */
.back-to-top {
    position: fixed;
    right: 20px;
    bottom: 20px; /* スマホの操作バーを考慮して調整 */
    width: 60px;
    height: 60px;
    background: #1a2a3a; /* リンク集と共通の濃紺 */
    color: #f1e4c1; /* リンク集と共通の金色 */
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    border: 2px solid #d4af37; /* アクセントカラーの金色 */
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    box-shadow: 0 4px 10px rgba(0,0,0,0.2);
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: #d4af37; /* ホバーで金色 */
    color: #1a2a3a; /* ホバーで濃紺 */
    transform: scale(1.05);
}

.back-to-top span {
    font-size: 1.2rem;
    line-height: 1;
}

.back-to-top small {
    font-size: 10px;
    font-weight: bold;
}

/* --- レスポンシブ調整 --- */
@media (max-width: 767px) {
    .stretch-header h1 {
        font-size: 1.8rem;
    }
    .intro-section {
        padding: 1.5rem !important;
    }
    .intro-title {
        font-size: 1.5rem;
    }
    .main-image img {
        max-height: 250px;
    }
    .detail-section-title {
        font-size: 1.6rem;
    }
    .stretch-name {
        font-size: 1.3rem;
        text-align: center;
    }
    .stretch-img {
        max-height: 200px;
    }
    .stretch-points {
        padding-left: 0;
    }
    .stretch-points li {
        text-align: left; /* スマホで箇条書きのテキストを左揃えに */
    }
    .stretch-points li::before {
        margin-left: 0;
    }
    .back-to-top {
        bottom: 70px; /* スマホのナビバーを考慮 */
        right: 15px;
        width: 50px;
        height: 50px;
    }
    .back-to-top span {
        font-size: 1rem;
    }
    .back-to-top small {
        font-size: 9px;
    }
    .category-card {
        padding: 1rem !important;
    }
    .category-card img {
        width: 60px;
        height: 60px;
    }
    .category-card h3 {
        font-size: 1.1rem;
    }
    .category-card p {
        font-size: 0.8rem;
    }
}