/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --accent-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --success-gradient: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
    --warning-gradient: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    --info-gradient: linear-gradient(135deg, #30cfd0 0%, #330867 100%);
    
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-light: #718096;
    --bg-white: #ffffff;
    --bg-gray: #f7fafc;
    --border-color: #e2e8f0;
    
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
    
    --border-radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Noto Sans SC', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-white);
    overflow-x: hidden;
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: var(--transition);
}

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

.logo {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.logo-text {
    font-size: 24px;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-family: 'Noto Sans JP', sans-serif;
}

.logo-subtitle {
    font-size: 12px;
    color: var(--text-light);
    letter-spacing: 1px;
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-links a:not(.btn-primary):hover {
    color: #667eea;
}

.nav-links a:not(.btn-primary)::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-gradient);
    transition: var(--transition);
}

.nav-links a:not(.btn-primary):hover::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 6px;
    cursor: pointer;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: white;
    box-shadow: var(--shadow-md);
    padding: 20px;
    flex-direction: column;
    gap: 16px;
    z-index: 999;
}

.mobile-menu a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    padding: 12px;
    border-radius: 8px;
    transition: var(--transition);
}

.mobile-menu a:hover {
    background: var(--bg-gray);
}

/* 按钮样式 */
.btn-primary,
.btn-secondary,
.btn-large {
    padding: 12px 24px;
    border-radius: 10px;
    font-weight: 600;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 16px;
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: white;
    color: #667eea;
    border: 2px solid #667eea;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
}

.btn-large {
    padding: 16px 32px;
    font-size: 18px;
}

/* Hero Section */
.hero {
    position: relative;
    padding: 140px 0 80px;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #f5f7fa 0%, #e9ecef 100%);
    z-index: -1;
}

.hero-background::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(102, 126, 234, 0.1) 0%, transparent 70%);
    border-radius: 50%;
}

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

.hero-title {
    font-size: 56px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 24px;
}

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

.hero-description {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 32px;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

.hero-stats {
    display: flex;
    gap: 48px;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 36px;
    font-weight: 700;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.stat-label {
    font-size: 14px;
    color: var(--text-light);
}

/* Phone Mockup */
.phone-mockup {
    width: 300px;
    height: 600px;
    background: linear-gradient(135deg, #1e1e1e 0%, #2d2d2d 100%);
    border-radius: 40px;
    padding: 12px;
    box-shadow: var(--shadow-xl);
    position: relative;
    margin: 0 auto;
}

.phone-mockup::before {
    content: '';
    position: absolute;
    top: 12px;
    left: 50%;
    transform: translateX(-50%);
    width: 120px;
    height: 20px;
    background: #1e1e1e;
    border-radius: 0 0 12px 12px;
    z-index: 10;
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 30px;
    overflow: hidden;
}

.app-preview {
    padding: 40px 20px 20px;
    height: 100%;
}

.preview-header {
    text-align: center;
    margin-bottom: 30px;
}

.preview-stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.preview-stat .kana {
    font-size: 72px;
    color: white;
    font-family: 'Noto Sans JP', sans-serif;
    text-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.preview-stat .level {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.9);
    font-weight: 500;
}

.preview-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.kana-card {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 16px;
    padding: 24px;
    text-align: center;
    font-family: 'Noto Sans JP', sans-serif;
    font-size: 48px;
    font-weight: 500;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.kana-card:nth-child(5) {
    grid-column: span 2;
}

.kana-card span {
    font-size: 14px;
    color: var(--text-light);
    font-family: 'Noto Sans SC', sans-serif;
}

/* Features Section */
.features {
    padding: 100px 0;
    background: white;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature-card {
    padding: 32px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    width: 64px;
    height: 64px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: white;
}

.gradient-1 { background: var(--primary-gradient); }
.gradient-2 { background: var(--secondary-gradient); }
.gradient-3 { background: var(--accent-gradient); }
.gradient-4 { background: var(--success-gradient); }
.gradient-5 { background: var(--warning-gradient); }
.gradient-6 { background: var(--info-gradient); }

.feature-card h3 {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Learning Path Section */
.learning-path {
    padding: 100px 0;
    background: var(--bg-gray);
}

.timeline {
    max-width: 800px;
    margin: 0 auto 60px;
    position: relative;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 3px;
    background: linear-gradient(to bottom, #667eea, #764ba2);
    transform: translateX(-50%);
}

.timeline-item {
    display: flex;
    gap: 40px;
    margin-bottom: 60px;
    position: relative;
}

.timeline-item:nth-child(odd) {
    flex-direction: row;
}

.timeline-item:nth-child(even) {
    flex-direction: row-reverse;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 80px;
    background: white;
    border: 4px solid #667eea;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10;
}

.week-number {
    font-weight: 700;
    font-size: 14px;
    color: #667eea;
}

.timeline-content {
    flex: 1;
    background: white;
    padding: 32px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    margin-top: 20px;
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-right: calc(50% + 40px);
}

.timeline-item:nth-child(even) .timeline-content {
    margin-left: calc(50% + 40px);
}

.timeline-content h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 8px;
}

.timeline-desc {
    color: var(--text-secondary);
    margin-bottom: 16px;
}

.kana-preview {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 20px;
    font-family: 'Noto Sans JP', sans-serif;
}

.kana-preview span {
    background: var(--bg-gray);
    padding: 8px 16px;
    border-radius: 8px;
    font-size: 18px;
    font-weight: 500;
}

.timeline-details {
    display: flex;
    gap: 24px;
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
    font-size: 14px;
}

.detail-item svg {
    color: #667eea;
}

/* Learning Tips */
.learning-tips {
    max-width: 900px;
    margin: 0 auto;
    background: white;
    padding: 40px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
}

.learning-tips h3 {
    font-size: 24px;
    margin-bottom: 24px;
    text-align: center;
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.tip-card {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px;
    background: var(--bg-gray);
    border-radius: 10px;
    transition: var(--transition);
}

.tip-card:hover {
    transform: translateX(4px);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
}

.tip-icon {
    font-size: 32px;
}

.tip-card p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Testimonials Section */
.testimonials {
    padding: 100px 0;
    background: white;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.testimonial-card {
    background: white;
    padding: 32px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.testimonial-card:hover {
    box-shadow: var(--shadow-lg);
}

.rating {
    color: #fbbf24;
    font-size: 20px;
    margin-bottom: 16px;
}

.testimonial-text {
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 24px;
    font-style: italic;
}

.testimonial-author {
    display: flex;
    gap: 16px;
    align-items: center;
}

.author-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--primary-gradient);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 18px;
}

.author-info {
    display: flex;
    flex-direction: column;
}

.author-name {
    font-weight: 600;
    color: var(--text-primary);
}

.author-level {
    font-size: 13px;
    color: var(--text-light);
}

/* Download CTA Section */
.download-cta {
    padding: 100px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.cta-content {
    max-width: 700px;
    margin: 0 auto;
}

.cta-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta-subtitle {
    font-size: 20px;
    opacity: 0.95;
    margin-bottom: 40px;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 24px;
}

.download-cta .btn-primary {
    background: white;
    color: #667eea;
}

.download-cta .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.2);
}

.cta-note {
    opacity: 0.9;
    font-size: 14px;
}

/* Footer */
.footer {
    padding: 60px 0 30px;
    background: #1a202c;
    color: white;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 40px;
}

.footer-logo {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 12px;
    font-family: 'Noto Sans JP', sans-serif;
}

.footer-desc {
    opacity: 0.8;
    line-height: 1.6;
}

.footer-section h4 {
    margin-bottom: 16px;
    font-weight: 600;
}

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

.footer-section ul li {
    margin-bottom: 8px;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
}

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

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    opacity: 0.7;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .hero-title {
        font-size: 48px;
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .hero-stats {
        gap: 32px;
    }
    
    .phone-mockup {
        width: 250px;
        height: 500px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .timeline::before {
        left: 20px;
    }
    
    .timeline-item {
        flex-direction: column !important;
        margin-left: 50px;
    }
    
    .timeline-marker {
        left: 20px;
    }
    
    .timeline-item .timeline-content {
        margin: 0 !important;
    }
    
    .tips-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    
    .cta-title {
        font-size: 32px;
    }
    
    .section-title {
        font-size: 32px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    
    .hero {
        padding: 120px 0 60px;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .hero-description {
        font-size: 16px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 24px;
    }
    
    .btn-large {
        padding: 14px 24px;
        font-size: 16px;
    }
    
    .phone-mockup {
        width: 220px;
        height: 440px;
    }
    
    .preview-stat .kana {
        font-size: 56px;
    }
    
    .kana-card {
        font-size: 36px;
        padding: 20px;
    }
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

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

.feature-card,
.timeline-item,
.testimonial-card {
    animation: fadeInUp 0.6s ease-out;
}