/* --- 基本設定と変数 --- */
:root {
    --primary-green: #2ecc71;
    --dark-bg: #1a1a1a;
    --dark-card-bg: #2c2c2c;
    --text-color: #f0f0f0;
    --text-muted: #a0a0a0;
    --font-primary: 'Noto Sans JP', sans-serif;
    --font-accent: 'Poppins', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    background-color: var(--dark-bg);
    color: var(--text-color);
    line-height: 1.7;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- ヘッダー --- */
.header {
    background: rgba(26, 26, 26, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #333;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    z-index: 1000;
}

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

.logo {
    font-family: var(--font-accent);
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-color);
    text-decoration: none;
}

.logo:hover {
    color: var(--primary-green);
}

.navbar {
    display: flex;
}

.nav-link {
    color: var(--text-muted);
    text-decoration: none;
    margin: 0 1.2rem;
    font-weight: 700;
    transition: color 0.3s ease;
}

.nav-link:hover {
    color: var(--primary-green);
}

.cta-button {
    background: linear-gradient(90deg, #2ecc71, #28b485);
    color: #fff;
    padding: 10px 24px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
    overflow: hidden;
}

.cta-button span {
    position: relative;
    z-index: 2;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(46, 204, 113, 0.2);
}

.menu-icon {
    display: none;
    font-size: 2rem;
    cursor: pointer;
}

/* --- ヒーローセクション --- */
.hero {
    height: 100vh;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
}

.hero-video-wrapper {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

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

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
}

.hero-content {
    position: relative;
    z-index: 2;
}

.hero-title {
    font-family: var(--font-accent);
    font-size: 5rem;
    font-weight: 900;
    letter-spacing: 2px;
    background: linear-gradient(90deg, #fff, #a0a0a0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 0.5rem;
}

.hero-subtitle {
    font-size: 1.8rem;
    font-weight: 400;
    margin-bottom: 2rem;
}

.hero-subtitle .highlight {
    color: var(--primary-green);
    font-weight: 700;
}

.hero-button {
    background: var(--primary-green);
    color: var(--white-color, #fff);
    padding: 1rem 2.5rem;
    font-size: 1.2rem;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 700;
    transition: all 0.3s ease;
}

.hero-button:hover {
    background: #27ae60;
    transform: scale(1.05);
}

/* --- 汎用セクションスタイル --- */
.content-section {
    padding: 100px 0;
}

.section-title {
    font-family: var(--font-accent);
    font-size: 2.8rem;
    text-align: center;
    margin-bottom: 1rem;
    letter-spacing: 2px;
    color: var(--text-color);
}

.section-subtitle {
    text-align: center;
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: 4rem;
}

/* --- コンセプトセクション --- */
.concept-text {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
    font-size: 1.1rem;
    line-height: 2;
}

/* --- 特徴セクション --- */
.features-section {
    background-color: #212121;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.feature-card {
    background-color: var(--dark-card-bg);
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    border: 1px solid #333;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.3);
}

.feature-icon-wrapper {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background-color: rgba(46, 204, 113, 0.1);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.feature-icon-wrapper img {
    width: 40px;
    height: 40px;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
}

/* --- 参加方法セクション --- */
.join-flow {
    display: flex;
    justify-content: space-around;
    align-items: center;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.step {
    text-align: center;
    max-width: 250px;
}

.step-circle {
    width: 70px;
    height: 70px;
    margin: 0 auto 20px;
    border: 3px solid var(--primary-green);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-green);
}

.step h4 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
}

.step-arrow {
    font-size: 2.5rem;
    color: var(--primary-green);
    margin: 0 1rem;
}

.join-section .hero-button {
    display: block;
    width: fit-content;
    margin: 0 auto;
}

/* --- FAQセクション --- */
.faq-section {
    background-color: #212121;
}
.faq-container {
    max-width: 800px;
    margin: 0 auto;
}
.faq-item {
    border-bottom: 1px solid #333;
}
.faq-question {
    width: 100%;
    padding: 20px;
    background: none;
    border: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    text-align: left;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-color);
    cursor: pointer;
}
.faq-icon {
    font-size: 1.5rem;
    color: var(--primary-green);
    transition: transform 0.3s ease;
}
.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-in-out;
}
.faq-answer p {
    padding: 0 20px 20px;
    color: var(--text-muted);
}
.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

/* --- フッター --- */
.footer {
    padding: 2rem 0;
    text-align: center;
    border-top: 1px solid #333;
}

/* --- アニメーション --- */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}


/* --- レスポンシブ対応 --- */
@media (max-width: 992px) {
    .navbar {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 80px;
        left: 0;
        width: 100%;
        background: var(--dark-bg);
    }
    .navbar.active {
        display: flex;
    }
    .nav-link {
        padding: 1rem;
        text-align: center;
    }
    .menu-icon {
        display: block;
    }
    .hero-title {
        font-size: 3.5rem;
    }
    .hero-subtitle {
        font-size: 1.4rem;
    }
    .step-arrow { display: none; }
    .join-flow { flex-direction: column; gap: 2rem; }
}
@media (max-width: 576px) {
    .hero-title { font-size: 2.5rem; }
    .hero-subtitle { font-size: 1.2rem; }
    .section-title { font-size: 2rem; }
}