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

body {
    font-family: 'Noto Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
}

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

/* Navbar */
.navbar {
    background-color: #fff;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-brand h1 {
    font-size: 1.8rem;
    color: #80CBC4;
    font-weight: 700;
}

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

.nav-links a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #80CBC4;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 4px;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 3px 0;
    transition: 0.3s;
    border-radius: 2px;
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

/* Mobile Menu Close Button - デスクトップでは非表示 */
.mobile-menu-close {
    display: none;
    position: absolute;
    top: 20px;
    right: 20px;
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: #333;
    padding: 10px;
    z-index: 1001;
}

/* Hero Section */
.hero {
    padding: 80px 0;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content h2 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: #1a1a1a;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 2rem;
    line-height: 1.8;
}

.download-btn {
    display: inline-block;
    transition: transform 0.2s;
}

.download-btn:hover {
    transform: scale(1.05);
}

.download-btn img {
    height: 60px;
    width: auto;
}

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

.phone-mockup {
    width: 300px;
    height: 600px;
    background-color: #1a1a1a;
    border-radius: 30px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.3);
    position: relative;
}

.phone-mockup::before {
    content: '';
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    width: 150px;
    height: 25px;
    background-color: #000;
    border-radius: 15px;
}

/* About & Features Section */
.features {
    padding: 80px 0;
    background-color: #fff;
}

.about-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.about-content p {
    font-size: 1.2rem;
    color: #666;
    line-height: 1.8;
}

.app-showcase {
    text-align: center;
    margin-bottom: 3rem;
}

.app-showcase h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #80CBC4;
}

.app-description {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 2rem;
    margin-top: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.6;
}

.features-subtitle {
    text-align: center;
    font-size: 1.5rem;
    margin-bottom: 2rem;
    color: #333;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    color: #1a1a1a;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card {
    background-color: #f8f9fa;
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.feature-card p {
    color: #666;
}

/* Download Section */
.download {
    padding: 80px 0;
    background-color: #f8f9fa;
    text-align: center;
}

.download-text {
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 2rem;
}

.download-btn-large {
    display: inline-block;
    transition: transform 0.2s;
}

.download-btn-large:hover {
    transform: scale(1.05);
}

.download-btn-large img {
    height: 70px;
    width: auto;
}

/* Footer */
.footer {
    background-color: #2c3e50;
    color: #fff;
    padding: 40px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 40px;
    margin-bottom: 30px;
}

.footer-section h3 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section a {
    color: #ecf0f1;
    text-decoration: none;
    line-height: 2;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: #3498db;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #34495e;
    color: #95a5a6;
}

/* Screenshot Carousel */
.screenshot-carousel {
    margin-top: 3rem;
    position: relative;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* Desktop: Grid layout */
@media (min-width: 769px) {
    .carousel-container {
        overflow: visible;
        border-radius: 0;
        box-shadow: none;
    }

    .carousel-track {
        display: grid;
        grid-template-columns: repeat(4, 1fr);
        gap: 20px;
        transition: none;
        transform: none !important;
    }

    .carousel-slide {
        min-width: auto;
        background-color: transparent;
        padding: 0;
    }

    .carousel-slide img {
        width: 170px;
        border-radius: 10px;
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        transition: transform 0.3s, box-shadow 0.3s;
    }

    .carousel-slide img:hover {
        transform: translateY(-5px);
        box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    }

    .carousel-btn,
    .carousel-dots {
        display: none;
    }
}

/* Mobile: Carousel layout */
@media (max-width: 768px) {
    .carousel-container {
        overflow: hidden;
        border-radius: 15px;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    }

    .carousel-track {
        display: flex;
        transition: transform 0.3s ease-in-out;
    }

    .carousel-slide {
        min-width: 100%;
        display: flex;
        justify-content: center;
        align-items: center;
        background-color: #f0f0f0;
        padding: 20px;
    }

    .carousel-slide img {
        width: 170px;
        height: auto;
        display: block;
    }

    .carousel-btn {
        position: absolute;
        top: 50%;
        transform: translateY(-50%);
        background-color: rgba(0, 0, 0, 0.5);
        color: white;
        border: none;
        font-size: 2rem;
        padding: 10px 15px;
        cursor: pointer;
        border-radius: 5px;
        transition: background-color 0.3s;
        z-index: 2;
    }

    .carousel-btn:hover {
        background-color: rgba(0, 0, 0, 0.7);
    }

    .carousel-btn-prev {
        left: 10px;
    }

    .carousel-btn-next {
        right: 10px;
    }

    .carousel-dots {
        display: flex;
        justify-content: center;
        gap: 8px;
        margin-top: 20px;
    }

    .carousel-dot {
        width: 10px;
        height: 10px;
        border-radius: 50%;
        background-color: #ccc;
        cursor: pointer;
        transition: background-color 0.3s;
    }

    .carousel-dot.active {
        background-color: #80CBC4;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .navbar .container {
        padding: 0.75rem 20px;
    }
    
    .nav-brand h1 {
        font-size: 1.5rem;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .nav-links {
        position: fixed;
        top: 0;
        left: -100%;
        width: 100%;
        height: 100vh;
        background-color: #fff;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 2rem;
        font-size: 1.2rem;
        transition: left 0.3s ease;
        z-index: 999;
    }
    
    .nav-links.mobile-active {
        left: 0;
    }
    
    .nav-links a {
        font-size: 1.2rem;
        padding: 1rem;
    }
    
    .mobile-menu-close {
        display: block; /* モバイルでは表示 */
    }
    
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content h2 {
        font-size: 2rem;
    }
    
    .hero-image {
        display: none;
    }
    
    .feature-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
}