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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
}

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

/* ナビゲーション */
nav {
    background: #1a1a1a;
    color: white;
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

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

nav h1 {
    font-size: 1.5rem;
    background: linear-gradient(135deg, #FF6B6B 0%, #4ECDC4 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

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

nav a {
    color: white;
    text-decoration: none;
    transition: opacity 0.3s;
}

nav a:hover {
    opacity: 0.8;
}

/* ヒーローセクション */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 150px 0 100px;
    text-align: center;
    margin-top: 60px;
}

.hero h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    line-height: 1.3;
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.btn-download {
    display: inline-block;
    background: white;
    color: #667eea;
    padding: 15px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    margin-top: 1rem;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

/* 機能セクション */
.features {
    padding: 80px 0;
    background: #f8f9fa;
}

.features h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
    color: #1a1a1a;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.12);
}

.feature-card h3 {
    color: #667eea;
    margin-bottom: 1rem;
    font-size: 1.3rem;
}

/* 用途セクション */
.use-cases {
    padding: 80px 0;
    background: white;
}

.use-cases h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
    color: #1a1a1a;
}

.use-case-list {
    max-width: 800px;
    margin: 0 auto;
    list-style: none;
}

.use-case-list li {
    padding: 1rem;
    margin-bottom: 1rem;
    background: #f8f9fa;
    border-radius: 8px;
    font-size: 1.1rem;
    transition: background 0.3s;
}

.use-case-list li:hover {
    background: #e9ecef;
}

/* お問い合わせセクション */
.contact {
    padding: 80px 0;
    background: #f8f9fa;
}

.contact h2 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.contact > p {
    text-align: center;
    margin-bottom: 3rem;
    color: #666;
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #333;
}

.required {
    color: #dc3545;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
}

.btn-submit {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 15px 40px;
    border: none;
    border-radius: 50px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    width: 100%;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-submit:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

/* フッター */
footer {
    background: #1a1a1a;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    nav .container {
        flex-direction: column;
        gap: 1rem;
    }
    
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1rem;
        font-size: 0.9rem;
    }
    
    .hero h2 {
        font-size: 2rem;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    .hero {
        margin-top: 100px;
        padding: 120px 0 80px;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
    }
    
    .use-case-list li {
        font-size: 1rem;
    }
}