:root {
    --dark-green: #0A400C;
    --medium-green: #819067;
    --light-green: #B1AB86;
    --cream: #FEFAE0;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', 'Hiragino Sans', 'Yu Gothic', sans-serif;
    line-height: 1.6;
    color: var(--dark-green);
    background: var(--cream);
}

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

/* ヒーローセクション */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--dark-green) 0%, var(--medium-green) 100%);
    position: relative;
    z-index: 1;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="25" cy="25" r="1" fill="%23FEFAE0" opacity="0.1"/><circle cx="75" cy="75" r="1" fill="%23FEFAE0" opacity="0.1"/><circle cx="50" cy="10" r="0.5" fill="%23FEFAE0" opacity="0.1"/><circle cx="10" cy="60" r="0.5" fill="%23FEFAE0" opacity="0.1"/><circle cx="90" cy="40" r="0.5" fill="%23FEFAE0" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 900px;
    text-align: center;
    color: var(--cream);
}

.hero-image {
    width: 280px;
    height: 280px;
    margin: 0 auto 40px;
    border-radius: 50%;
    overflow: hidden;
    border: 4px solid var(--light-green);
    box-shadow: 0 20px 60px rgba(10, 64, 12, 0.3);
    transition: transform 0.3s ease;
}

.hero-image:hover {
    transform: scale(1.05);
}

.hero-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.hero h1 {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 20px;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--cream) 0%, var(--light-green) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.4rem;
    margin-bottom: 30px;
    opacity: 0.9;
    font-weight: 400;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 0;
    opacity: 0.8;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}

/* セクション共通スタイル */
.section {
    padding: 100px 0;
    position: relative;
    z-index: 2;
}

.section:nth-child(even) {
    background: linear-gradient(135deg, var(--cream) 0%, #f8f6f0 100%);
}

.section-title {
    text-align: center;
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 60px;
    color: var(--dark-green);
    position: relative;
    letter-spacing: -0.02em;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: var(--medium-green);
    border-radius: 2px;
}

/* 特徴セクション */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
    margin-top: 80px;
}

.feature-card {
    background: white;
    padding: 50px 40px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 10px 40px rgba(10, 64, 12, 0.08);
    transition: all 0.3s ease;
    border: 1px solid rgba(177, 171, 134, 0.2);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 60px rgba(10, 64, 12, 0.15);
}

.feature-icon {
    font-size: 3.5rem;
    margin-bottom: 25px;
    filter: grayscale(20%);
}

.feature-card h3 {
    font-size: 1.6rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--dark-green);
}

.feature-card p {
    color: var(--medium-green);
    line-height: 1.8;
    font-size: 1rem;
}

/* 開催情報セクション */
.event-info {
    background: linear-gradient(135deg, var(--medium-green) 0%, var(--dark-green) 100%);
    color: var(--cream);
}

.event-info .section-title {
    color: var(--cream);
}

.event-info .section-title::after {
    background: var(--light-green);
}

.event-details {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 60px;
}

.event-detail {
    background: rgba(254, 250, 224, 0.1);
    padding: 40px 30px;
    border-radius: 16px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(254, 250, 224, 0.2);
    text-align: center;
    transition: transform 0.3s ease;
}

.event-detail:hover {
    transform: translateY(-5px);
}

.event-detail h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--light-green);
}

.event-detail p {
    font-size: 1.1rem;
    opacity: 0.9;
    line-height: 1.6;
}

/* 参加方法セクション */
.participation-styles {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
    margin-top: 80px;
}

.participation-card {
    background: linear-gradient(135deg, var(--light-green) 0%, var(--medium-green) 100%);
    padding: 40px 35px;
    border-radius: 20px;
    text-align: center;
    color: var(--cream);
    box-shadow: 0 15px 40px rgba(129, 144, 103, 0.2);
    transition: all 0.3s ease;
}

.participation-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 25px 60px rgba(129, 144, 103, 0.3);
}

.participation-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 20px;
}

.participation-card p {
    opacity: 0.95;
    line-height: 1.8;
    font-size: 1rem;
}

/* フッター */
.footer {
    background: var(--dark-green);
    color: var(--cream);
    text-align: center;
    padding: 60px 0;
}

.footer p {
    opacity: 0.8;
    font-size: 1rem;
}

/* レスポンシブ */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.8rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .hero-description {
        font-size: 1rem;
    }

    .hero-image {
        width: 220px;
        height: 220px;
    }

    .section-title {
        font-size: 2.2rem;
    }

    .features {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .feature-card {
        padding: 40px 30px;
    }

    .section {
        padding: 80px 0;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero h1 {
        font-size: 2.4rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .participation-styles,
    .event-details {
        grid-template-columns: 1fr;
    }
}

/* 第1回の内容セクション */
.vol1-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
    margin-top: 40px;
}

.vol1-image {
    position: sticky;
    top: 100px;
}

.vol1-summary-image {
    width: 100%;
    height: auto;
    border-radius: 16px;
    box-shadow: 0 20px 40px rgba(10, 64, 12, 0.15);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.vol1-summary-image:hover {
    transform: translateY(-5px);
    box-shadow: 0 25px 50px rgba(10, 64, 12, 0.2);
}

.vol1-details {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.vol1-info h3,
.vol1-topics h3,
.vol1-highlights h3,
.vol1-decisions h3 {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--dark-green);
    display: flex;
    align-items: center;
    gap: 8px;
}

.vol1-info p {
    font-size: 1.1rem;
    color: var(--cream);
    background: linear-gradient(135deg, var(--medium-green) 0%, var(--dark-green) 100%);
    padding: 12px 20px;
    border-radius: 8px;
    font-weight: 500;
}

.topic-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 20px;
    margin-top: 20px;
}

.topic-item {
    display: flex;
    gap: 16px;
    padding: 20px;
    background: rgba(254, 250, 224, 0.7);
    border-radius: 12px;
    border-left: 4px solid var(--medium-green);
    transition: all 0.3s ease;
}

.topic-item:hover {
    background: rgba(254, 250, 224, 0.9);
    transform: translateX(5px);
    box-shadow: 0 4px 12px rgba(129, 144, 103, 0.2);
}

.topic-icon {
    font-size: 1.5rem;
    min-width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--cream);
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(10, 64, 12, 0.1);
}

.topic-content h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-green);
    margin-bottom: 8px;
}

.topic-content p {
    font-size: 0.95rem;
    color: var(--medium-green);
    line-height: 1.6;
}

.highlights-list,
.decisions-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.highlights-list li,
.decisions-list li {
    padding: 12px 0;
    border-bottom: 1px solid var(--light-green);
    color: var(--medium-green);
    line-height: 1.6;
    position: relative;
    padding-left: 24px;
}

.highlights-list li:before,
.decisions-list li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--medium-green);
    font-weight: bold;
}

.highlights-list li:last-child,
.decisions-list li:last-child {
    border-bottom: none;
}

.highlights-list li strong {
    color: var(--dark-green);
    font-weight: 600;
}

/* 第1回セクションのレスポンシブ対応 */
@media (max-width: 768px) {
    .vol1-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .vol1-image {
        position: static;
        order: -1;
    }
    
    .topic-item {
        flex-direction: column;
        text-align: center;
        gap: 12px;
    }
    
    .topic-icon {
        align-self: center;
    }
}