:root {
    /* 核心色盘 - 实用主义 */
    --bg-color: #FFFFFF;
    --surface-color: #F5F5F7;
    --text-primary: #111111;
    --text-secondary: #666666;
    --border-color: #E5E5E5;
    
    /* 动作色 */
    --action-color: #007AFF;

    /* 排版 */
    --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --max-width: 960px;
    --header-height: 60px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-stack);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.5;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--text-primary);
}

.text-display {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.text-display a {
    color: inherit;
    text-decoration: none;
    transition: opacity 0.2s ease;
}

.text-display a:hover {
    opacity: 0.8;
    text-decoration: none;
}

.text-headline {
    font-size: 16px;
    font-weight: 500;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.text-body {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 16px;
}

a {
    text-decoration: none;
    color: inherit;
}

/* --- Layout & Navigation --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 max(24px, env(safe-area-inset-right));
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
}

.nav-brand {
    font-weight: 600;
    font-size: 18px;
}

.nav-lang {
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    color: var(--action-color);
}

main {
    padding-top: var(--header-height);
    max-width: var(--max-width);
    margin: 0 auto;
}

/* --- App Section Block --- */
.app-section {
    padding: 60px 24px;
    border-bottom: 1px solid var(--border-color);
}

.app-section:last-child {
    border-bottom: none;
}

.container {
    display: flex;
    flex-direction: row; /* 默认左右布局 */
    gap: 40px;
    align-items: flex-start;
}

/* --- Hero Content (Left Side) --- */
.hero-content {
    flex: 0 0 320px; /* 固定左侧宽度 */
    text-align: left;
}

.app-icon {
    width: 80px;
    height: 80px;
    margin-bottom: 20px;
    border-radius: 50%; /* 圆形图标 */
    border: 1px solid rgba(0,0,0,0.05);
}

/* --- Buttons --- */
.btn-group {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    margin-top: 24px;
}

.btn {
    display: inline-flex;
    align-items: center;
    padding: 8px 16px;
    border-radius: 6px; /* 小圆角 */
    font-weight: 500;
    font-size: 13px;
    transition: opacity 0.2s;
}

.btn:hover {
    opacity: 0.8;
}

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

.btn-secondary {
    background-color: var(--surface-color);
    color: var(--action-color);
}

/* --- Features List --- */
.features {
    margin-top: 24px;
    font-size: 13px;
}

.feature-item {
    margin-bottom: 8px;
    color: var(--text-secondary);
    display: flex;
    align-items: baseline;
}

.feature-icon {
    margin-right: 8px;
    color: var(--text-primary);
    font-size: 10px; /* 小点 */
}

/* --- Showcase (Right Side - Screenshots) --- */
.showcase {
    flex: 1;
    display: flex;
    gap: 16px;
    overflow-x: auto; /* 允许横向滚动 */
    padding-bottom: 12px; /* 滚动条空间 */
    /* 隐藏滚动条但保留功能 */
    scrollbar-width: thin;
    -webkit-overflow-scrolling: touch;
    /* 关键修复：确保容器内的图片不被压缩 */
    min-width: 0; 
}

.screenshot-container {
    flex: 0 0 auto; /* 防止 flex 压缩，保持图片原始比例 */
}

.screenshot {
    height: 400px; /* 固定高度，确保无论横竖屏都在一行内对齐 */
    width: auto;   /* 宽度自适应，保证长宽比不失真 */
    max-width: none; /* 防止被父容器限制宽度 */
    border-radius: 8px;
    border: 1px solid var(--border-color);
    display: block;
    object-fit: contain; /* 兜底：如果被强行拉伸，保持内容完整 */
}

/* --- Mobile Optimization --- */
@media (max-width: 768px) {
    .app-section {
        padding: 40px 20px;
    }

    .text-display {
        font-size: 2rem; /* 32px */
    }

    .container {
        flex-direction: column; /* 手机端上下布局 */
        gap: 24px;
    }
    
    .hero-content {
        flex: auto;
        width: 100%;
    }
    
    .showcase {
        width: 100%;
        /* 手机端允许全宽滚动，不再受限于 container padding */
        margin-left: -20px;
        margin-right: -20px;
        padding-left: 20px;
        padding-right: 20px;
        
        /* 滚动捕捉体验优化 */
        scroll-snap-type: x mandatory;
        padding-bottom: 20px; /* 增加底部空间，避免滚动条遮挡太近 */
    }

    .screenshot-container {
        scroll-snap-align: center; /* 居中捕捉 */
    }
    
    .screenshot {
        height: 300px; /* 手机端截图高度适当减小，适应屏幕 */
        max-width: 80vw; /* 防止过宽的图片撑满屏幕，留出一点预览空间 */
        object-fit: contain;
    }

    .btn {
        padding: 10px 20px; /* 更大的点击区域 */
        font-size: 14px;
    }
}

/* --- Footer --- */
footer {
    padding: 40px 24px;
    text-align: center;
    color: var(--text-secondary);
    font-size: 12px;
    background-color: var(--surface-color);
    border-top: 1px solid var(--border-color);
}

footer img {
    vertical-align: middle;
    margin-right: 4px;
}

footer a {
    color: var(--text-secondary);
}

footer a:hover {
    text-decoration: underline;
}