/* --- 基本設定 --- */
:root {
    --main-font: 'Noto Sans JP', sans-serif;
    --heading-font: 'M PLUS Rounded 1c', sans-serif;
    --bg-color: #FFFFF8; /* オフホワイト */
    --text-color: #333;
    --accent-color: #8dc63f; /* 緑 */
    --highlight-color: #d5eeaf; /* パステルグリーン */
    --white: #fff;
    --gray: #777;
}

body {
    font-family: var(--main-font);
    line-height: 1.8;
    color: var(--text-color);
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
    font-size: 16px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
}

h1, h2, h3, h4 {
    font-family: var(--heading-font);
    font-weight: 800;
    line-height: 1.5;
    margin-top: 0;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: opacity 0.3s;
}

a:hover {
    opacity: 0.8;
}

img {
    max-width: 100%;
    height: auto;
}

section {
    padding: 60px 0;
}

.section-title {
    font-size: 2.2rem;
    text-align: center;
    margin-bottom: 40px;
}

.section-text {
    max-width: 700px;
    margin: 0 auto 20px auto;
    text-align: center;
}

.marker-highlight {
    background: linear-gradient(transparent 60%, var(--highlight-color) 60%);
    padding: 0 0.2em;
}

.text-highlight {
    font-weight: 700;
    color: var(--accent-color);
}

/* --- 言語切り替え --- */
.language-switcher {
    background-color: #f0f0f0;
    padding: 8px 0;
    text-align: right;
}
.language-switcher a {
    color: #555;
    font-size: 0.9rem;
    font-weight: 700;
    text-decoration: none;
}

/* --- ヒーローセクション --- */
.hero {
    background-color: var(--white);
    padding: 40px 0;
    border-bottom: 2px dashed var(--highlight-color);
}

.hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 40px;
}

.hero-text {
    flex: 1;
}

.main-catchphrase {
    font-size: 2.8rem;
    font-weight: 800;
    margin-bottom: 20px;
}

.sub-catchphrase {
    font-size: 1.2rem;
    font-family: var(--heading-font);
    font-weight: 500;
}

.hero-image {
    flex: 0 0 300px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    border-radius: 8px;
    overflow: hidden;
}

/* --- 問題提起セクション --- */
.problem-section {
    background-color: var(--white);
}

.dialog-style {
    background-color: var(--bg-color);
    border: 2px solid var(--highlight-color);
    border-radius: 15px;
    padding: 20px 30px;
    max-width: 600px;
    margin: 30px auto;
    text-align: center;
    font-family: var(--heading-font);
    font-weight: 500;
    font-size: 1.1rem;
}
.dialog-style p {
    margin: 10px 0;
}

/* --- 広告プレースホルダ --- */
.ad-placeholder {
    padding: 20px 0;
    text-align: center;
    color: var(--gray);
}

/* --- 解決策提示セクション --- */
.changes-box {
    background-color: var(--white);
    border-radius: 15px;
    padding: 40px;
    margin-top: 40px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    border: 1px solid #eee;
}
.changes-box h3 {
    text-align: center;
    font-size: 1.5rem;
    margin-bottom: 40px;
}

.changes-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.change-item {
    text-align: center;
}

.change-icon {
    font-size: 2.5rem;
    color: var(--accent-color);
    margin-bottom: 15px;
}

.change-item h4 {
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.change-item p {
    font-size: 0.95rem;
    text-align: left;
}

/* --- 内容紹介セクション --- */
.features-section {
    background-color: var(--white);
}

.chapters {
    background-color: var(--bg-color);
    border: 2px dashed var(--accent-color);
    border-radius: 10px;
    padding: 30px;
    max-width: 700px;
    margin: 30px auto 0;
}
.chapters h4 {
    font-size: 1.3rem;
    text-align: center;
    margin-bottom: 20px;
}
.chapters ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.chapters li {
    padding: 10px 0;
    border-bottom: 1px solid var(--highlight-color);
}
.chapters li:last-child {
    border-bottom: none;
}
.chapter-label {
    background-color: var(--accent-color);
    color: var(--white);
    font-family: var(--heading-font);
    padding: 3px 10px;
    border-radius: 5px;
    margin-right: 15px;
    font-size: 0.9rem;
}

/* --- レビューセクション --- */
.reviews-section {
    background-color: var(--bg-color);
}
.reviews-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-top: 40px;
}
.review-card {
    background-color: var(--white);
    border: 1px solid #eee;
    border-radius: 10px;
    padding: 30px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
}
.review-title {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: #E6A320; /* 星の色をイメージ */
}
.review-body {
    font-size: 0.95rem;
    line-height: 1.7;
}


/* --- CTAセクション --- */
.cta-section {
    background-color: var(--highlight-color);
    text-align: center;
}
.closing-message {
    font-family: var(--heading-font);
    font-weight: 500;
    font-size: 1.2rem;
    margin-bottom: 30px;
}
.cta-buttons {
    margin-top: 30px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}
.cta-button {
    display: inline-block;
    padding: 15px 30px;
    border-radius: 50px;
    font-family: var(--heading-font);
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--white);
    text-align: center;
    min-width: 320px;
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
    transition: transform 0.2s, box-shadow 0.2s;
}
.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 15px rgba(0,0,0,0.15);
    opacity: 1;
}
.cta-button.amazon {
    background-color: #FF9900;
}
.cta-button.amazon-paper {
    background-color: #232f3e;
}
.cta-button.app {
    background-color: var(--accent-color);
}
.cta-button i {
    margin-right: 10px;
}

/* --- フッター --- */
.site-footer {
    background-color: #333;
    color: #ccc;
    padding: 30px 0;
    text-align: center;
}
.social-links {
    margin-bottom: 15px;
}
.social-links a {
    color: var(--white);
    font-size: 1.8rem;
    margin: 0 10px;
}
.copyright {
    font-size: 0.9rem;
}

/* --- ページトップへ戻るボタン --- */
.back-to-top-button {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    background-color: var(--accent-color);
    color: var(--white);
    border-radius: 50%;
    text-align: center;
    line-height: 50px;
    font-size: 1.5rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
    display: none; /* JSで表示制御 */
}
.back-to-top-button:hover {
    background-color: #79b332;
    opacity: 1;
}

/* --- レスポンシブ対応 --- */
@media (max-width: 768px) {
    .section-title { font-size: 1.8rem; }
    
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    .hero-image {
        order: -1; /* 画像を上へ */
        margin-bottom: 30px;
        flex-basis: auto;
        width: 250px;
    }
    .main-catchphrase { font-size: 2.2rem; }
    .sub-catchphrase { font-size: 1.1rem; }

    .changes-grid {
        grid-template-columns: 1fr;
    }
    .change-item p {
        max-width: 400px;
        margin-left: auto;
        margin-right: auto;
    }
    
    .reviews-grid {
        grid-template-columns: 1fr;
    }

    .cta-button {
        width: 100%;
        max-width: 320px;
        min-width: auto;
    }
}