/* --- 全局变量 (黑金风格核心配置) --- */
:root {
    --bg-dark: #0F0F0F;
    --bg-card: #161616;
    --text-main: #E0E0E0;
    --text-muted: #888888;
    --gold-primary: #D4AF37;
    --gold-gradient: linear-gradient(135deg, #bf953f, #fcf6ba, #b38728, #fbf5b7, #aa771c);
    --gold-glow: 0 0 15px rgba(212, 175, 55, 0.3);
}

/* --- 基础重置 --- */
* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; outline: none; }
html { scroll-behavior: smooth; }
body {
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.7;
    overflow-x: hidden;
}
a { text-decoration: none; color: inherit; transition: 0.3s; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.text-center { text-align: center; }

.gradient-text {
    background: var(--gold-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    display: inline-block;
}

/* --- 导航栏 (Sticky Header) --- */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(15, 15, 15, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid #2a2a2a;
}
.nav-box {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}
.logo { font-size: 26px; font-weight: 800; font-family: serif; letter-spacing: 1px; }
.nav-links { display: flex; gap: 30px; font-size: 14px; color: var(--text-main); }
.nav-links a:hover { color: var(--gold-primary); }
.nav-btn {
    background: var(--gold-gradient);
    color: #000;
    padding: 8px 24px;
    border-radius: 30px;
    font-weight: bold;
    font-size: 14px;
    box-shadow: 0 4px 10px rgba(180, 140, 40, 0.2);
}

@media (max-width: 768px) { .nav-links { display: none; } }

/* --- 首屏海报 Banner (Hero Section) --- */
.hero {
    padding-top: 160px; /* 增加顶部距离 */
    padding-bottom: 100px;
    text-align: center;
    position: relative;
    /* === 核心修改区：Banner 背景图配置 ===
       1. linear-gradient: 用于制造黑色遮罩，保证文字清晰。rgba(0,0,0,0.7) 代表70%透明度的黑色。
       2. url: 请将 'images/banner-bg.webp' 替换为您实际的横幅图片路径。建议使用暗色调、扑克元素的图片。
    */
    background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.85)), 
                url('../images/banner.png') no-repeat center center;
    background-size: cover; /* 确保图片覆盖全屏 */
}

.hero h1 {
    font-size: clamp(2rem, 6vw, 3.8rem);
    margin-bottom: 20px;
    font-weight: 800;
    line-height: 1.2;
    text-shadow: 0 4px 10px rgba(0,0,0,0.8); /* 增加文字投影，提升可读性 */
}
.hero p {
    color: #ccc; /* 稍微调亮文字颜色以适应Banner */
    font-size: 1.1rem;
    max-width: 640px;
    margin: 0 auto 50px;
    text-shadow: 0 2px 5px rgba(0,0,0,0.8);
}
.version-info {
    font-size: 12px; 
    margin-top: 20px; 
    color: #888;
}

.cta-group {
    display: flex;
    justify-content: center;
    gap: 25px;
    flex-wrap: wrap;
}
.btn-download {
    width: 220px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    font-weight: bold;
    font-size: 17px;
    transition: transform 0.3s, box-shadow 0.3s;
    cursor: pointer;
}
/* iOS 按钮 */
.btn-ios {
    background: var(--gold-gradient);
    color: #111;
    box-shadow: var(--gold-glow);
}
/* Android 按钮 */
.btn-android {
    background: rgba(0,0,0,0.6); /* 给按钮加个底色，防止背景太花看不清 */
    border: 2px solid var(--gold-primary);
    color: var(--gold-primary);
}
.btn-download:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(212, 175, 55, 0.25);
}

/* --- 通用板块 --- */
section { padding: 70px 0; border-bottom: 1px solid #1a1a1a; }
.section-title {
    font-size: 2.2rem;
    margin-bottom: 15px;
    text-align: center;
    color: #fff;
    font-weight: bold;
}
.title-line {
    width: 60px;
    height: 4px;
    background: var(--gold-primary);
    margin: 0 auto 50px;
    border-radius: 2px;
}

.content-box {
    background: var(--bg-card);
    padding: 50px;
    border-radius: 16px;
    border: 1px solid #252525;
    box-shadow: 0 20px 40px rgba(0,0,0,0.3);
}
.content-box p { margin-bottom: 25px; text-indent: 2em; text-align: justify; color: #ccc; }
.content-box strong { color: var(--gold-primary); font-weight: 600; }

/* --- 核心价值图片模块 --- */
.visual-section { background: #111; }
.concept-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}
.concept-card {
    background: transparent;
    border-radius: 12px;
    overflow: hidden;
    transition: transform 0.3s ease;
}
.concept-card:hover { transform: translateY(-10px); }
.img-wrapper {
    width: 100%;
    height: 240px;
    overflow: hidden;
    border-radius: 12px;
    position: relative;
    background: #1a1a1a;
    border: 1px solid #333;
    display: flex;
    align-items: center;
    justify-content: center;
}
.img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s ease;
    opacity: 0.9;
}
.concept-card:hover .img-wrapper img { transform: scale(1.1); opacity: 1; }
.card-text { padding: 25px 10px; text-align: center; }
.card-text h3 { color: #eee; font-size: 1.3rem; margin-bottom: 10px; }
.card-text p { color: #777; font-size: 0.95rem; }

/* --- 特色功能 (Features) --- */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}
@media (max-width: 1024px) {
    .feature-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
    .feature-grid { grid-template-columns: 1fr; }
}
.feature-card {
    background: var(--bg-card);
    padding: 40px 30px;
    border-radius: 12px;
    text-align: center;
    border: 1px solid #222;
    transition: 0.3s;
}
.feature-card:hover { border-color: var(--gold-primary); background: #1c1c1c; }
.f-icon { font-size: 40px; margin-bottom: 20px; display: inline-block; }
.feature-card h4 { margin-bottom: 15px; font-size: 1.2rem; color: #fff; }
.feature-desc { color: #888; font-size: 0.9rem; }

/* --- 下载教程 (Steps) --- */
.tutorial-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 50px;
}
.step-list { counter-reset: step; margin-top: 20px; }
.step-item { position: relative; padding-left: 50px; margin-bottom: 25px; }
.step-item::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 0; top: 2px;
    width: 32px; height: 32px;
    background: var(--gold-primary);
    color: #000;
    border-radius: 50%;
    text-align: center;
    line-height: 32px;
    font-weight: bold;
    font-size: 14px;
}
.step-head { color: #fff; font-weight: bold; margin-bottom: 5px; font-size: 1.05rem; }
.step-body { color: #888; font-size: 0.95rem; }

/* --- FAQ --- */
.faq-box { background: transparent; border: none; box-shadow: none; padding: 0; }
.faq-item { margin-bottom: 30px; border-left: 3px solid #333; padding-left: 20px; transition: 0.3s; }
.faq-item:hover { border-left-color: var(--gold-primary); }
.faq-q { font-weight: bold; color: var(--gold-primary); margin-bottom: 10px; font-size: 1.1rem; }
.faq-item p { text-indent: 0; margin-bottom: 0; }

/* --- Footer --- */
footer { padding: 60px 0 100px; background: #0a0a0a; text-align: center; font-size: 0.9rem; color: #666; border-top: 1px solid #222; }
.f-links a { margin: 0 15px; color: #888; }
.f-links a:hover { color: var(--gold-primary); }
.copyright { margin-top: 20px; }
.disclaimer { max-width: 800px; margin: 30px auto 0; font-size: 0.8rem; line-height: 1.5; opacity: 0.7; }

/* --- 移动端悬浮底栏 --- */
.sticky-footer {
    display: none;
    position: fixed; bottom: 0; left: 0; width: 100%;
    background: rgba(20, 20, 20, 0.98);
    padding: 12px 20px;
    border-top: 1px solid #333;
    z-index: 999;
    justify-content: space-between; align-items: center;
    backdrop-filter: blur(5px);
}
.footer-brand { color: #fff; font-weight: bold; display: flex; align-items: center; }
.brand-name { font-family: serif; margin-right: 10px; color: var(--gold-primary); }
.brand-badge { font-size: 12px; color: #888; }
.sticky-btn { background: var(--gold-gradient); color: #000; padding: 6px 18px; border-radius: 20px; font-size: 14px; font-weight: bold; }

@media (max-width: 768px) {
    .sticky-footer { display: flex; }
    .hero h1 { font-size: 2rem; }
    .content-box { padding: 25px; }
    .nav-btn { display: none; }
}