/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #007AFF;
    --text-dark: #1d1d1f;
    --text-light: #6e6e73;
    --bg-light: #f5f5f7;
    --bg-white: #ffffff;
    --accent-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Language Switcher */
.language-switcher {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    display: flex;
    gap: 10px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    padding: 8px;
    border-radius: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.lang-btn {
    padding: 8px 16px;
    border: none;
    background: transparent;
    color: var(--text-light);
    font-size: 0.9rem;
    cursor: pointer;
    border-radius: 15px;
    transition: all 0.3s ease;
    font-weight: 500;
}

.lang-btn:hover {
    background: var(--bg-light);
}

.lang-btn.active {
    background: var(--primary-color);
    color: white;
}

/* Language Display */
.lang-en, .lang-ja {
    display: none !important;
}

body[data-lang="en"] .lang-en {
    display: inline !important;
}

body[data-lang="ja"] .lang-ja {
    display: inline !important;
}

/* For block-level language elements (not currently used but available) */
body[data-lang="en"] .lang-en.block {
    display: block !important;
}

body[data-lang="ja"] .lang-ja.block {
    display: block !important;
}

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

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(180deg, #ffffff 0%, #f5f5f7 100%);
    padding: 60px 20px;
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 5rem);
    font-weight: 700;
    letter-spacing: -0.03em;
    margin-bottom: 30px;
    line-height: 1.1;
    opacity: 0;
    animation: fadeInUp 1s ease forwards;
}

.highlight {
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 3vw, 1.5rem);
    color: var(--text-light);
    margin-bottom: 40px;
    opacity: 0;
    animation: fadeInUp 1s ease 0.2s forwards;
}

.cta-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    opacity: 0;
    animation: fadeInUp 1s ease 0.4s forwards;
}

.btn {
    padding: 15px 40px;
    border-radius: 980px;
    font-size: 1.1rem;
    text-decoration: none;
    transition: all 0.3s ease;
    font-weight: 500;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: #0051D5;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 122, 255, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
}

/* What is Section */
.what-is {
    padding: 100px 20px;
    background: var(--bg-white);
    text-align: center;
}

.what-is h2 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    font-weight: 600;
}

.what-is-intro {
    font-size: 1.2rem;
    line-height: 1.8;
    color: var(--text-light);
    margin-bottom: 50px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.what-is-list {
    list-style: none;
    max-width: 600px;
    margin: 0 auto;
    text-align: left;
}

.what-is-list li {
    padding: 15px 0;
    padding-left: 30px;
    position: relative;
    font-size: 1.1rem;
    color: var(--text-dark);
    line-height: 1.6;
}

.what-is-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
    font-size: 1.3rem;
}

/* Features Section */
.features {
    padding: 120px 20px;
    background: var(--bg-white);
}

.features .container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 60px;
}

.feature {
    text-align: center;
    padding: 40px 20px;
}

.feature-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.feature h2 {
    font-size: 2rem;
    margin-bottom: 15px;
    font-weight: 600;
}

.feature p {
    color: var(--text-light);
    font-size: 1.1rem;
    line-height: 1.6;
}

/* Download Section */
.download {
    padding: 120px 20px;
    background: var(--bg-light);
    text-align: center;
}

.download h2 {
    font-size: 2.5rem;
    margin-bottom: 60px;
    font-weight: 600;
}

.platform-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    max-width: 900px;
    margin: 0 auto;
}

.platform {
    background: var(--bg-white);
    padding: 40px 20px;
    border-radius: 20px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.platform:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.platform-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

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

.platform p {
    color: var(--text-light);
}

/* Support Section */
.support {
    padding: 120px 20px;
    background: var(--bg-white);
    text-align: center;
}

.support h2 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    font-weight: 600;
}

.support p {
    color: var(--text-light);
    font-size: 1.2rem;
    margin-bottom: 40px;
    line-height: 1.8;
}

/* Footer */
.footer {
    padding: 60px 20px;
    background: var(--text-dark);
    color: white;
    text-align: center;
}

.footer-links {
    margin-top: 20px;
    display: flex;
    gap: 30px;
    justify-content: center;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s ease;
}

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

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive */
@media (max-width: 768px) {
    .hero {
        min-height: 80vh;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
    }
    
    .features .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}