/* Color Palette & Variables */
:root {
    --bg-color: #FAF9F6; /* 初雪白 */
    --text-color: #333333; /* 深岩灰 */
    --text-light: #666666;
    --primary-color: #FFB6C1; /* 樱花淡粉 */
    --secondary-color: #AEC6CF; /* 温和婴儿蓝 */
    --card-bg: #FFFFFF;
    --border-color: #EEEEEE;
    --border-radius: 16px;
    --transition: 0.3s ease-in-out;
}

/* CSS Reset & Setup */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Quicksand', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Hiragino Sans GB', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Nunito', -apple-system, BlinkMacSystemFont, 'PingFang SC', sans-serif;
    font-weight: 700;
    line-height: 1.3;
}

.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

a {
    color: #007AFF; /* iOS Blue for links */
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    opacity: 0.8;
}

/* Header */
.navbar {
    padding: 20px 0;
    position: sticky;
    top: 0;
    width: 100%;
    background-color: rgba(250, 249, 246, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.app-icon {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

.brand-name {
    font-size: 20px;
    font-weight: 800;
    font-family: 'Nunito', sans-serif;
}

/* Language & Platform Switcher */
.nav-controls {
    display: flex;
    align-items: center;
    gap: 20px;
}

.lang-switch, .platform-switch {
    font-size: 14px;
    display: flex;
    align-items: center;
    background-color: var(--card-bg);
    border-radius: 20px;
    padding: 4px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.lang-switch button, .platform-switch button {
    background: none;
    border: none;
    color: var(--text-light);
    cursor: pointer;
    font-family: inherit;
    font-size: inherit;
    padding: 6px 12px;
    border-radius: 16px;
    transition: var(--transition);
}

.lang-switch button:hover, .platform-switch button:hover {
    color: var(--text-color);
}

.lang-switch button.active, .platform-switch button.active {
    color: var(--text-color);
    background-color: var(--bg-color);
    font-weight: 700;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

/* Hero Section */
.hero {
    padding: 80px 0 100px;
}

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

.hero-text {
    flex: 1;
    max-width: 500px;
}

.hero-text h1 {
    font-size: 48px;
    margin-bottom: 16px;
    color: var(--text-color);
}

.hero-text .subtitle {
    font-size: 20px;
    color: var(--text-light);
    font-weight: 500;
    margin-bottom: 40px;
}

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

.hero-image-placeholder {
    width: 300px;
    height: 600px;
    background: linear-gradient(135deg, var(--bg-color), var(--primary-color));
    border-radius: 40px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.08);
    opacity: 0.8;
}

/* Phone Mockup Frame */
.phone-mockup {
    width: 280px; /* Scales down iPhone 17 Pro Max proportionally */
    border-radius: 44px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.15);
    border: 10px solid #111;
    background-color: #111;
    overflow: hidden;
    object-fit: cover;
    display: block;
}

.feature-icon-circle {
    width: 120px;
    height: 120px;
    background-color: rgba(255, 182, 193, 0.15);
    border-radius: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 10px 30px rgba(255, 182, 193, 0.3);
}

.cta-buttons {
    display: flex;
    gap: 15px;
    margin-top: 20px;
    flex-wrap: wrap;
}

.cta-button {
    display: inline-block;
}

.cta-button img {
    height: 48px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    border: 0;
}

/* Features Section */
.features {
    padding: 60px 0;
    background-color: #FFFFFF;
}

.feature-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
    margin-bottom: 100px;
}

.feature-item.reverse {
    flex-direction: row-reverse;
}

.feature-item:last-child {
    margin-bottom: 0;
}

.feature-text {
    flex: 1;
}

.feature-text h2 {
    font-size: 32px;
    margin-bottom: 16px;
}

.feature-text p {
    font-size: 18px;
    color: var(--text-light);
}

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

.feature-placeholder {
    width: 100%;
    max-width: 400px;
    height: 300px;
    background-color: var(--bg-color);
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-light);
    font-size: 16px;
    border: 1px dashed var(--secondary-color);
    padding: 20px;
    text-align: center;
}

/* Testimonial Section */
.testimonial {
    padding: 100px 0;
    text-align: center;
    background: linear-gradient(180deg, #FFFFFF 0%, var(--bg-color) 100%);
}

.testimonial .quote {
    font-size: 24px;
    font-style: italic;
    color: var(--text-color);
    max-width: 700px;
    margin: 0 auto 20px;
    font-weight: 500;
}

.testimonial .author {
    font-size: 16px;
    color: var(--text-light);
}

/* Footer Section */
footer {
    padding: 40px 0 60px;
    text-align: center;
}

.footer-links {
    margin-bottom: 24px;
    display: flex;
    justify-content: center;
    gap: 24px;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-light);
    font-size: 14px;
    font-weight: 500;
}

.footer-links a:hover {
    color: var(--text-color);
}

.copyright {
    font-size: 12px;
    color: #999;
}

/* Animation */
.slide-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.slide-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive Design */
@media (max-width: 992px) {
    .hero-content {
        gap: 20px;
    }
    
    .hero-text h1 {
        font-size: 40px;
    }
}

@media (max-width: 768px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-text {
        max-width: 100%;
        margin-bottom: 40px;
    }
    
    .hero-text .subtitle {
        margin-bottom: 30px;
    }
    
    .hero-image-wrapper {
        width: 100%;
    }
    
    .hero-image-placeholder {
        width: 260px;
        height: 520px;
    }

    .phone-mockup {
        width: 240px;
    }

    .feature-item,
    .feature-item.reverse {
        flex-direction: column;
        text-align: center;
        gap: 30px;
        margin-bottom: 60px;
    }
    
    .feature-text h2 {
        font-size: 28px;
    }
    
    .feature-placeholder {
        height: 250px;
    }
    
    .testimonial .quote {
        font-size: 20px;
    }
}