:root {
    --primary: #4CAF50;
    --primary-light: #81C784;
    --primary-dark: #388E3C;
    --bg-color: #f4f9f4;
    --text-color: #333;
    --text-muted: #666;
    --card-bg: #fff;
    --radius: 12px;
    --border-color: #e0e0e0;
}

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

body {
    font-family: 'Inter', 'Noto Sans JP', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

a {
    color: var(--primary);
    text-decoration: none;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

.narrow {
    max-width: 700px;
}

/* Header */
.header {
    background-color: var(--card-bg);
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.header h1, .header h1 a {
    font-size: 1.2rem;
    font-weight: 800;
    color: var(--primary-dark);
}

.header nav {
    display: flex;
    gap: 20px;
}

.header nav a {
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 600;
    transition: color 0.2s;
}

.header nav a:hover {
    color: var(--primary);
}

/* Hero Section */
.hero {
    padding: 80px 0;
    background: linear-gradient(135deg, #e8f5e9 0%, #c8e6c9 100%);
}

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

.hero-text {
    flex: 1;
}

.hero-text h2 {
    font-size: 2.5rem;
    line-height: 1.3;
    margin-bottom: 20px;
    color: var(--primary-dark);
}

.hero-text p {
    font-size: 1.1rem;
    margin-bottom: 30px;
    color: var(--text-muted);
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 30px;
    font-weight: 600;
    text-align: center;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
    box-shadow: 0 4px 15px rgba(76, 175, 80, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(76, 175, 80, 0.6);
    color: white;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

/* Chat Mockup */
.mockup {
    width: 300px;
    height: 400px;
    background-color: var(--card-bg);
    border-radius: 30px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    border: 8px solid #333;
    padding: 20px;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
}

.mockup-chat {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.bubble {
    padding: 12px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    max-width: 85%;
    line-height: 1.4;
}

.bubble.user {
    align-self: flex-end;
    background-color: var(--primary);
    color: white;
    border-bottom-right-radius: 4px;
}

.bubble.ai {
    align-self: flex-start;
    background-color: #f1f3f4;
    color: var(--text-color);
    border-bottom-left-radius: 4px;
}

/* Features */
.features {
    padding: 80px 0;
}

.features h3 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 40px;
    color: var(--primary-dark);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.feature-card {
    background: var(--card-bg);
    padding: 30px;
    border-radius: var(--radius);
    box-shadow: 0 5px 20px rgba(0,0,0,0.03);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-card h4 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: var(--primary-dark);
}

/* Page Content (Privacy, Terms, FAQ) */
.page-content {
    padding: 60px 0;
    background-color: var(--card-bg);
    min-height: calc(100vh - 150px);
}

.page-content h2 {
    font-size: 2rem;
    margin-bottom: 10px;
    color: var(--primary-dark);
}

.page-content .date {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 30px;
}

.page-content h3 {
    font-size: 1.3rem;
    margin: 35px 0 15px;
    padding-bottom: 5px;
    border-bottom: 2px solid var(--primary-light);
    color: var(--primary-dark);
}

.page-content h4 {
    font-size: 1.1rem;
    margin: 20px 0 10px;
    color: var(--text-color);
}

.page-content p {
    margin-bottom: 15px;
}

.page-content ul, .page-content ol {
    margin-bottom: 20px;
    padding-left: 25px;
}

.page-content li {
    margin-bottom: 8px;
}

.page-content table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

.page-content th, .page-content td {
    border: 1px solid var(--border-color);
    padding: 10px;
    text-align: left;
}

.page-content th {
    background-color: var(--bg-color);
    color: var(--primary-dark);
}

/* FAQ specifics */
.faq-item {
    margin-bottom: 25px;
    background: #fafafa;
    padding: 20px;
    border-radius: var(--radius);
}

.faq-item h4 {
    margin-top: 0;
    color: var(--primary-dark);
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.faq-item h4::before {
    content: "Q.";
    color: var(--primary);
    font-weight: 800;
}

/* Footer */
footer {
    background-color: var(--primary-dark);
    color: rgba(255,255,255,0.8);
    padding: 40px 0 20px;
    text-align: center;
}

footer .container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.footer-nav {
    display: flex;
    gap: 30px;
    flex-wrap: wrap;
    justify-content: center;
}

.footer-nav a {
    color: rgba(255,255,255,0.9);
    font-size: 0.95rem;
    font-weight: 600;
}

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

.footer-copy {
    font-size: 0.85rem;
    margin-top: 10px;
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 20px;
    width: 100%;
}

@media (max-width: 768px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }

    .hero-text h2 {
        font-size: 2rem;
    }

    .header .container {
        flex-direction: column;
        justify-content: center;
        gap: 10px;
        height: auto;
        padding: 15px 20px;
    }

    .header nav {
        flex-wrap: wrap;
        justify-content: center;
    }
}