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

:root {
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --text-color: #1e293b;
    --text-light: #64748b;
    --bg-color: #ffffff;
    --bg-light: #f8fafc;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
    background: var(--bg-color);
}

.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, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 64px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 600;
}

.logo {
    font-size: 24px;
}

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

.nav-links a {
    color: var(--text-color);
    text-decoration: none;
    font-size: 15px;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--primary-color);
}

/* 主页横幅 */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #f8fafc 0%, #e0e7ff 100%);
}

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

.hero-content {
    max-width: 540px;
}

.hero-title {
    font-size: 56px;
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 24px;
    color: var(--text-color);
}

.hero-subtitle {
    font-size: 20px;
    color: var(--text-light);
    margin-bottom: 32px;
}

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

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 16px;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s;
    cursor: pointer;
}

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

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: white;
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

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

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

/* 拍立得模型 */
.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.polaroid-mockup {
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-20px); }
}

.polaroid-frame {
    background: white;
    padding: 16px;
    padding-bottom: 60px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
    border-radius: 4px;
    transform: rotate(-3deg);
}

.polaroid-photo {
    width: 280px;
    height: 280px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    margin-bottom: 12px;
}

.polaroid-caption {
    text-align: center;
    font-family: "Courier New", monospace;
    color: var(--text-light);
    font-size: 14px;
}

/* 特性区域 */
.features {
    padding: 80px 0;
    background: var(--bg-color);
}

.section-title {
    text-align: center;
    font-size: 40px;
    font-weight: 700;
    margin-bottom: 60px;
}

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

.feature-card {
    padding: 32px;
    background: var(--bg-light);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.3s;
}

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

.feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-light);
    font-size: 15px;
    line-height: 1.6;
}

/* 下载区域 */
.download {
    padding: 80px 0;
    background: var(--bg-light);
}

.download-subtitle {
    text-align: center;
    color: var(--text-light);
    font-size: 18px;
    margin-bottom: 40px;
}

.download-card {
    max-width: 700px;
    margin: 0 auto;
    padding: 40px;
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 32px;
}

.download-info h3 {
    font-size: 24px;
    margin-bottom: 8px;
}

.download-info p {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 4px;
}

.compatibility {
    font-size: 13px;
    opacity: 0.8;
}

.app-store-icon {
    margin-right: 8px;
}

.download-note {
    text-align: center;
    margin-top: 24px;
    color: var(--text-light);
    font-size: 14px;
}

/* 关于区域 */
.about {
    padding: 80px 0;
    background: white;
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-content > p {
    font-size: 18px;
    line-height: 1.8;
    color: var(--text-color);
    margin-bottom: 24px;
    text-align: center;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
    margin-top: 48px;
}

.about-item {
    text-align: center;
    padding: 24px;
}

.about-item h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: var(--text-color);
}

.about-item p {
    font-size: 15px;
    color: var(--text-light);
    line-height: 1.6;
}

/* 页脚 */
.footer {
    padding: 40px 0;
    background: var(--text-color);
    color: white;
}

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

.footer-left {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 500;
}

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

.footer-right a {
    color: white;
    text-decoration: none;
    transition: opacity 0.2s;
}

.footer-right a:hover {
    opacity: 0.8;
}

.separator {
    opacity: 0.5;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-title {
        font-size: 40px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .hero-image {
        order: -1;
    }

    .polaroid-frame {
        transform: scale(0.8) rotate(-3deg);
    }

    .features-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .download-card {
        flex-direction: column;
        text-align: center;
    }

    .about-features {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .nav-links {
        gap: 16px;
        font-size: 14px;
    }

    .footer-content {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}