/* ========================================
   リセット & ベーススタイル
======================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 図書館風カラーパレット */
    --primary-brown: #6B4423;
    --secondary-brown: #8B6F47;
    --light-beige: #F5F1E8;
    --cream: #FAF7F0;
    --dark-green: #3A5A40;
    --accent-gold: #C9A961;
    --text-dark: #2C2416;
    --text-medium: #5C4F3D;
    --border-color: #D4C5B0;
    --shadow: rgba(107, 68, 35, 0.1);
    
    /* フォント */
    --font-sans: 'Noto Sans JP', sans-serif;
    --font-serif: 'Noto Serif JP', serif;
}

body {
    font-family: var(--font-sans);
    background-color: var(--cream);
    color: var(--text-dark);
    line-height: 1.8;
    font-size: 16px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s ease;
}

/* ========================================
   ヘッダー
======================================== */
.header {
    background: linear-gradient(135deg, var(--primary-brown) 0%, var(--secondary-brown) 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo i {
    font-size: 2rem;
}

.logo h1 {
    font-family: var(--font-serif);
    font-size: 1.5rem;
    font-weight: 600;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.main-nav a {
    color: white;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    transition: all 0.3s ease;
}

.main-nav a:hover,
.main-nav a.active {
    background: rgba(255, 255, 255, 0.2);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: white;
    font-size: 1.5rem;
    cursor: pointer;
}

.mobile-menu {
    display: none;
    background: var(--primary-brown);
    padding: 1rem;
}

.mobile-menu ul {
    list-style: none;
}

.mobile-menu li {
    margin: 0.5rem 0;
}

.mobile-menu a {
    color: white;
    display: block;
    padding: 0.75rem;
    border-radius: 5px;
    transition: background 0.3s ease;
}

.mobile-menu a:hover,
.mobile-menu a.active {
    background: rgba(255, 255, 255, 0.2);
}

/* ========================================
   ヒーローセクション
======================================== */
.hero {
    background: linear-gradient(135deg, var(--light-beige) 0%, var(--cream) 100%);
    padding: 5rem 0;
    border-bottom: 3px solid var(--border-color);
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-text {
    text-align: left;
}

.hero-image {
    order: 2;
}

.hero-title {
    font-family: var(--font-serif);
    font-size: 3rem;
    color: var(--primary-brown);
    margin-bottom: 1rem;
    line-height: 1.4;
}

.hero-subtitle {
    font-size: 1.3rem;
    color: var(--text-medium);
    margin-bottom: 2rem;
}

.hero-message {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    max-width: 700px;
    margin: 2rem auto;
    box-shadow: 0 4px 15px var(--shadow);
    border-left: 5px solid var(--accent-gold);
}

.hero-message p {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.hero-message p:last-child {
    margin-bottom: 0;
    font-weight: 500;
    color: var(--dark-green);
}

.cta-button {
    display: inline-block;
    background: var(--dark-green);
    color: white;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    font-size: 1.1rem;
    font-weight: 500;
    margin-top: 2rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(58, 90, 64, 0.3);
}

.cta-button:hover {
    background: #2d4530;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(58, 90, 64, 0.4);
}

/* ========================================
   クイック統計
======================================== */
.quick-stats {
    padding: 3rem 0;
    background: white;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.stat-card {
    background: var(--light-beige);
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px var(--shadow);
}

.stat-card i {
    font-size: 3rem;
    color: var(--dark-green);
    margin-bottom: 1rem;
}

.stat-card h3 {
    font-family: var(--font-serif);
    color: var(--primary-brown);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.stat-card p {
    color: var(--text-medium);
    font-size: 1rem;
    font-weight: 500;
}

/* ========================================
   ロードマップセクション
======================================== */
.roadmap {
    padding: 5rem 0;
    background: var(--cream);
}

.section-title {
    font-family: var(--font-serif);
    font-size: 2.5rem;
    text-align: center;
    color: var(--primary-brown);
    margin-bottom: 1rem;
}

.section-subtitle {
    text-align: center;
    color: var(--text-medium);
    font-size: 1.1rem;
    margin-bottom: 3rem;
}

.roadmap-steps {
    max-width: 800px;
    margin: 0 auto;
}

.roadmap-step {
    display: flex;
    gap: 2rem;
    align-items: flex-start;
    margin-bottom: 2rem;
}

.step-number {
    background: var(--primary-brown);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 10px;
    font-weight: 700;
    font-size: 1.1rem;
    white-space: nowrap;
    box-shadow: 0 3px 10px var(--shadow);
}

.step-content {
    flex: 1;
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 3px 15px var(--shadow);
    border-left: 4px solid var(--accent-gold);
}

.step-content h3 {
    font-family: var(--font-serif);
    color: var(--primary-brown);
    margin-bottom: 0.75rem;
    font-size: 1.3rem;
}

.step-content h3 i {
    color: var(--dark-green);
    margin-right: 0.5rem;
}

.step-content p {
    color: var(--text-medium);
    margin-bottom: 1rem;
}

.step-link {
    display: inline-block;
    color: var(--dark-green);
    font-weight: 500;
    margin-top: 0.5rem;
    transition: all 0.3s ease;
}

.step-link:hover {
    color: var(--primary-brown);
    transform: translateX(5px);
}

.step-links {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.roadmap-arrow {
    text-align: center;
    color: var(--accent-gold);
    font-size: 2rem;
    margin: 1rem 0;
}

/* ========================================
   ライブラリー（本棚）セクション
======================================== */
.library {
    padding: 5rem 0;
    background: var(--light-beige);
}

.bookshelf {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.book-card {
    background: white;
    padding: 2.5rem;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 5px 20px var(--shadow);
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
    position: relative;
}

.book-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 30px rgba(107, 68, 35, 0.2);
    border-color: var(--accent-gold);
}

.book-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--dark-green), #4a7350);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.book-icon i {
    font-size: 2.5rem;
    color: white;
}

.book-card h3 {
    font-family: var(--font-serif);
    color: var(--primary-brown);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.book-card p {
    color: var(--text-medium);
    line-height: 1.6;
}

.book-badge {
    display: inline-block;
    background: var(--accent-gold);
    color: white;
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    margin-top: 1rem;
}

/* ========================================
   重要メッセージセクション
======================================== */
.important-message {
    padding: 5rem 0;
    background: var(--cream);
}

.message-box {
    background: linear-gradient(135deg, #fff9e6 0%, #fffdf7 100%);
    padding: 3rem;
    border-radius: 15px;
    box-shadow: 0 5px 25px var(--shadow);
    border: 3px solid var(--accent-gold);
    max-width: 900px;
    margin: 0 auto;
}

.message-box > i {
    font-size: 3rem;
    color: var(--dark-green);
    display: block;
    text-align: center;
    margin-bottom: 1.5rem;
}

.message-box h3 {
    font-family: var(--font-serif);
    font-size: 1.8rem;
    color: var(--primary-brown);
    text-align: center;
    margin-bottom: 2rem;
}

.message-content p {
    margin-bottom: 1.5rem;
    font-size: 1.05rem;
}

.message-content strong {
    color: var(--primary-brown);
}

.message-content ul {
    list-style: none;
    margin: 1.5rem 0;
    padding-left: 1rem;
}

.message-content ul li {
    margin: 0.75rem 0;
    font-size: 1.05rem;
    padding-left: 0.5rem;
}

.correct-list {
    margin-top: 1rem;
}

.message-emphasis {
    font-weight: 600;
    color: var(--dark-green);
    font-size: 1.15rem;
    text-align: center;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 2px solid var(--accent-gold);
}

/* ========================================
   コンテンツページ共通スタイル
======================================== */
.page-header {
    background: linear-gradient(135deg, var(--primary-brown) 0%, var(--secondary-brown) 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.page-title {
    font-family: var(--font-serif);
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.page-subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
}

.content-section {
    padding: 4rem 0;
}

.content-section:nth-child(even) {
    background: var(--light-beige);
}

.content-section:nth-child(odd) {
    background: white;
}

.content-box {
    background: white;
    padding: 2.5rem;
    border-radius: 10px;
    margin-bottom: 2rem;
    box-shadow: 0 3px 15px var(--shadow);
    border-left: 5px solid var(--accent-gold);
}

.content-box h3 {
    font-family: var(--font-serif);
    color: var(--primary-brown);
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
}

.content-box h4 {
    color: var(--dark-green);
    font-size: 1.3rem;
    margin: 2rem 0 1rem;
}

.content-box p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

.content-box ul,
.content-box ol {
    margin: 1.5rem 0;
    padding-left: 2rem;
}

.content-box li {
    margin: 0.75rem 0;
    line-height: 1.7;
}

.highlight-box {
    background: var(--light-beige);
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid var(--dark-green);
    margin: 1.5rem 0;
}

.warning-box {
    background: #fff3cd;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #ff9800;
    margin: 1.5rem 0;
}

.success-box {
    background: #d4edda;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid var(--dark-green);
    margin: 1.5rem 0;
}

/* ========================================
   フッター
======================================== */
.footer {
    background: var(--primary-brown);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    font-family: var(--font-serif);
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin: 0.5rem 0;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: white;
}

.disclaimer {
    font-size: 0.9rem;
    line-height: 1.6;
    color: rgba(255, 255, 255, 0.8);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    color: rgba(255, 255, 255, 0.7);
}

/* ========================================
   レスポンシブデザイン
======================================== */
@media (max-width: 768px) {
    .main-nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .mobile-menu.active {
        display: block;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .hero-text {
        text-align: center;
    }
    
    .hero-image {
        order: 1;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .roadmap-step {
        flex-direction: column;
    }
    
    .step-number {
        align-self: flex-start;
    }
    
    .bookshelf {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .message-box {
        padding: 2rem;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
}