@import url('https://fonts.googleapis.com/css2?family=Zhi+Mang+Xing&family=Noto+Serif+SC:wght@400;500;600&display=swap');

:root {
    --bg-color: #fdfbf7;           /* 极其浅淡的暖色背景 */
    --paper-color: #fffdfa;        /* 微黄的信纸白 */
    --text-main: #4a4036;          /* 深灰棕色，不刺眼 */
    --text-muted: #8c7b6c;         /* 浅褐色辅助文字 */
    --accent-color: #FFB822;       /* 高级复古红（火漆色） */
    --accent-hover: #E5A110;
    --line-color: #ede2d7;         /* 信纸的墨水横线 */
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--bg-color);
    /* 细腻的信纸网格底纹 */
    background-image: 
        radial-gradient(rgba(203, 190, 180, 0.25) 1px, transparent 1px),
        radial-gradient(rgba(203, 190, 180, 0.25) 1px, transparent 1px);
    background-size: 40px 40px;
    background-position: 0 0, 20px 20px;
    font-family: "Noto Serif SC", serif;
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* --- 导航栏 --- */
.top-nav {
    width: 100%;
    padding: 20px 0;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 100;
    background: rgba(253, 251, 247, 0.85); /* 顶部做了一点毛玻璃，但不破坏复古感 */
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(220, 210, 200, 0.4);
}

.nav-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-text {
    font-family: 'Zhi Mang Xing', cursive;
    font-size: 26px;
    color: var(--accent-color);
    letter-spacing: 2px;
}

.nav-links {
    display: flex;
    gap: 35px;
}

.nav-links a {
    color: var(--text-main);
    text-decoration: none;
    font-size: 15px;
    letter-spacing: 1px;
    transition: color 0.3s ease;
}

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

/* --- 主体双列排版 (绝佳适配Web) --- */
.home-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 140px 30px 60px;
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 80px;
    box-sizing: border-box;
}

/* --- 左半边：文案与操作 --- */
.hero-content {
    flex: 1;
    max-width: 480px;
}

.stamp-wrap {
    display: inline-block;
    padding: 8px;
    background: #fff;
    border: 1px dashed #d1c1b3;
    margin-bottom: 30px;
    box-shadow: 2px 4px 12px rgba(138, 115, 95, 0.08);
    transform: rotate(-3deg);
    transition: transform 0.4s ease;
}

.stamp-wrap:hover {
    transform: rotate(0deg) scale(1.03);
}

.app-icon {
    width: 65px;
    height: 65px;
    display: block;
    object-fit: cover;
}

.main-title {
    font-size: 58px;
    font-family: 'Zhi Mang Xing', cursive;
    font-weight: normal;
    margin: 0;
    color: var(--text-main);
    letter-spacing: 8px;
}

.tagline {
    font-size: 16px;
    letter-spacing: 14px;
    color: var(--text-muted);
    margin: 12px 0 30px 4px;
    text-transform: uppercase;
}

.intro-text {
    font-size: 15px;
    line-height: 2.2;
    color: #6a5d51;
    margin-bottom: 40px;
    opacity: 0.9;
    letter-spacing: 1px;
}

/* 操作区域 */
.action-group {
    display: flex;
    gap: 20px;
    margin-bottom: 15px;
}

.action-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px; /* SVG icon与文字的间距 */
    padding: 12px 30px;
    border-radius: 30px;
    font-size: 15px;
    letter-spacing: 1.5px;
    text-decoration: none;
    transition: all 0.3s ease;
}

.btn-icon {
    margin-bottom: 2px; /* 光学视觉微调 */
}

.primary-btn {
    background-color: var(--accent-color);
    color: #fff;
    box-shadow: 0 6px 20px rgba(255, 184, 34, 0.25);
}

.primary-btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 184, 34, 0.35);
}

.app-store-btn {
    background-color: transparent;
    color: var(--text-main);
    border: 1px solid #dcd1c7;
}

.app-store-btn:hover {
    background-color: #f6efe9;
    border-color: #c7b6a7;
}

.status-text {
    font-size: 12px;
    color: #baa898;
    letter-spacing: 1px;
    margin-bottom: 50px;
    padding-left: 10px;
}

/* 数据统计 */
.stats-footer {
    display: flex;
    gap: 50px;
    opacity: 0.85;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-muted);
}

.stat-icon {
    font-size: 22px;
    display: flex;
    align-items: center;
    opacity: 0.8;
}

.stat-number {
    font-size: 20px;
    font-family: -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-main);
    font-weight: 600;
}

.stat-label {
    font-size: 12px;
    letter-spacing: 1px;
}

/* --- 右半边：真假难辨的实体信纸 --- */
.hero-visual {
    flex: 1;
    display: flex;
    justify-content: flex-end;
    perspective: 1200px; /* 伪3D视角 */
}

.letter-paper {
    background-color: var(--paper-color);
    width: 100%;
    max-width: 440px;
    padding: 60px 40px 80px;
    box-sizing: border-box;
    border-radius: 2px;
    /* 纸张的立体阴影 */
    box-shadow: -15px 15px 40px rgba(162, 142, 124, 0.15), 
                0 0 0 1px rgba(234, 221, 211, 0.6) inset;
    transform: rotate(2deg); /* 随性的倾斜 */
    position: relative;
    /* 画出漂亮的信纸横线 */
    background-image: repeating-linear-gradient(transparent, transparent 39px, var(--line-color) 39px, var(--line-color) 40px);
    background-position: 0 45px;
    transition: transform 0.6s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

/* 鼠标停留在信纸上时的互动 */
.letter-paper:hover {
    transform: rotate(0deg) translateY(-5px);
}

/* 信封顶部的半透明胶带装饰 */
.tape {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%) rotate(-2deg);
    width: 120px;
    height: 35px;
    background-color: rgba(255, 255, 255, 0.35);
    box-shadow: 0 1px 3px rgba(0,0,0,0.06);
    backdrop-filter: blur(4px);
    border-radius: 2px;
}

.poetry {
    font-size: 17px;
    color: #5c5044;
    line-height: 40px; /* 字体行高精准对齐背景横线 */
    text-align: center;
    position: relative;
    z-index: 2;
}

.poetry p {
    margin: 0;
}

/* 亮色强调诗句 */
.poetry .highlight {
    color: var(--accent-color);
    font-weight: 500;
}

.signature {
    margin-top: 40px;
    text-align: right;
    font-size: 14px;
    color: var(--text-muted);
}

/* --- 完美的移动端适配 (竖屏折叠排版) --- */
@media (max-width: 860px) {
    .nav-container {
        flex-direction: column;
        gap: 12px;
    }
    
    .nav-links {
        gap: 25px;
    }

    .home-container {
        /* 在手机上强制改为上下结构 */
        flex-direction: column;
        justify-content: center;
        text-align: center;
        padding-top: 140px;
        gap: 60px;
    }

    .hero-content {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    .tagline {
        margin-left: 0;
    }

    .intro-text {
        max-width: 90%;
    }

    .action-group {
        flex-direction: column;
        width: 100%;
        max-width: 280px;
    }

    .action-btn {
        width: 100%;
        box-sizing: border-box;
    }
    
    .status-text {
        padding-left: 0;
        margin-bottom: 40px;
    }

    .stats-footer {
        justify-content: center;
        gap: 40px;
    }

    .hero-visual {
        justify-content: center;
        width: 100%;
        perspective: none;
    }

    .letter-paper {
        /* 手机上为了阅读舒适取消倾斜和巨大阴影 */
        transform: none;
        padding: 40px 20px 60px;
        box-shadow: 0 10px 30px rgba(162, 142, 124, 0.1);
        background-position: 0 25px;
        max-width: 100%;
    }
    
    .letter-paper:hover {
        transform: none;
    }

    .tape {
        display: none; /* 手机屏拥挤，隐藏多余装饰 */
    }
}