/*
   主题：轻语科技 (Whisper Tech)
   风格：深色、玻璃态 (Glassmorphism)、赛博朋克微光、流畅过渡动画
*/

:root {
    --primary-color: #00f2fe;     /* 科技青蓝 */
    --primary-hover: #4facfe;
    --primary-glow: rgba(0, 242, 254, 0.5);
    --bg-main: #05050f;           /* 深空黑 */
    --bg-card: rgba(15, 23, 42, 0.4); /* 玻璃态暗影 */
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --white: #ffffff;
    --border-color: rgba(255, 255, 255, 0.1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-main);
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(0, 242, 254, 0.08), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(79, 172, 254, 0.08), transparent 25%);
    background-attachment: fixed;
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
    100% { transform: translateY(0px); }
}

@keyframes glow {
    0% { box-shadow: 0 0 10px rgba(0, 242, 254, 0.2); }
    50% { box-shadow: 0 0 25px rgba(0, 242, 254, 0.6); }
    100% { box-shadow: 0 0 10px rgba(0, 242, 254, 0.2); }
}

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

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

/* 顶部导航栏 - 玻璃拟物化 */
.top-nav {
    background-color: rgba(5, 5, 15, 0.6);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}
.nav-container { display: flex; justify-content: space-between; align-items: center; height: 70px; }
.logo { font-size: 1.6rem; font-weight: 900; background: linear-gradient(135deg, #00f2fe, #4facfe); -webkit-background-clip: text; -webkit-text-fill-color: transparent; letter-spacing: 1px;}
.nav-links { display: flex; list-style: none; gap: 30px; }
.nav-links a { color: var(--text-main); font-weight: 500; transition: color 0.3s; position: relative;}
.nav-links a::after { content: ''; position: absolute; bottom: -5px; left: 0; width: 0%; height: 2px; background: var(--primary-color); transition: width 0.3s; box-shadow: 0 0 8px var(--primary-color); }
.nav-links a:hover { color: var(--primary-color); }
.nav-links a:hover::after { width: 100%; }

.nav-btn {
    padding: 8px 24px;
    font-size: 0.95rem;
    background: rgba(0, 242, 254, 0.1);
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    border-radius: 20px;
    transition: all 0.3s;
    box-shadow: none;
}
.nav-btn:hover {
    background: var(--primary-color);
    color: #000;
    box-shadow: 0 0 15px var(--primary-glow);
}

/* 按钮 - 赛博渐变光效 */
.btn {
    display: inline-block;
    background: linear-gradient(135deg, #00f2fe, #4facfe);
    color: #000;
    padding: 14px 32px;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 700;
    text-align: center;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    border: none;
    animation: glow 3s infinite;
}
.btn:hover {
    transform: translateY(-2px) scale(1.05);
    animation: none;
    box-shadow: 0 0 25px var(--primary-color);
}
.btn-alt {
    background: rgba(255, 255, 255, 0.05);
    color: var(--white);
    border: 1px solid var(--border-color);
    animation: none;
    backdrop-filter: blur(5px);
}
.btn-alt:hover {
    background: rgba(255, 255, 255, 0.15);
    box-shadow: 0 0 20px rgba(255,255,255,0.2);
    color: var(--white);
}

/* 通用区块 */
section { padding: 90px 0; }
.section-title { text-align: center; font-size: 2.2rem; margin-bottom: 16px; color: var(--white); font-weight: 700; letter-spacing: 2px; }
.section-subtitle { text-align: center; color: var(--text-muted); font-size: 1.1rem; margin-bottom: 50px; font-weight: 300; }

/* 主视觉区 (Hero) */
.hero {
    padding: 150px 20px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.hero::before {
    content: ''; position: absolute; top: -30%; left: 50%; transform: translateX(-50%); width: 70vw; height: 70vw; background: radial-gradient(circle, rgba(0, 242, 254, 0.15) 0%, transparent 60%); z-index: -1;
}
.hero h1 { font-size: 4rem; font-weight: 900; margin-bottom: 24px; line-height: 1.2; letter-spacing: 2px; background: linear-gradient(135deg, #ffffff 30%, #00f2fe 100%); -webkit-background-clip: text; -webkit-text-fill-color: transparent; filter: drop-shadow(0 0 20px rgba(0,242,254,0.3)); }
.hero p { font-size: 1.25rem; color: var(--text-muted); max-width: 700px; margin: 0 auto 40px; font-weight: 300; }

.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; }

/* 玻璃态卡片通用 */
.card, .ai-media-card, .price-card, .faq-item, .review-card, .page-content {
    background: var(--bg-card);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    padding: 40px 30px;
    border-radius: 16px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}
.card:hover, .ai-media-card:hover, .review-card:hover { 
    transform: translateY(-10px); 
    border-color: rgba(0, 242, 254, 0.4); 
    box-shadow: 0 15px 35px rgba(0, 242, 254, 0.15); 
}

/* 卡片内部细节 */
.card .icon { font-size: 3rem; margin-bottom: 20px; animation: float 4s ease-in-out infinite; display: inline-block; filter: drop-shadow(0 0 10px var(--primary-glow)); }
.card h3 { font-size: 1.3rem; margin-bottom: 12px; color: var(--white); }
.card p { color: var(--text-muted); font-size: 0.95rem; font-weight: 300; }

.ai-media-card h3 { font-size: 1.5rem; margin-bottom: 15px; color: var(--primary-color); }
.ai-media-card p { color: var(--text-muted); margin-bottom: 20px; font-weight: 300; }
.tags-container { display: flex; flex-wrap: wrap; gap: 10px; }
.tag { background: rgba(0, 242, 254, 0.05); padding: 6px 16px; border-radius: 20px; font-size: 0.9rem; color: var(--primary-color); border: 1px solid rgba(0, 242, 254, 0.2); transition: all 0.3s; }
.tag:hover { background: var(--primary-color); color: #000; box-shadow: 0 0 15px var(--primary-glow); }

/* 套餐价格 */
.price-card { text-align: center; position: relative; }
.price-card.popular { border-color: var(--primary-color); box-shadow: 0 0 30px rgba(0, 242, 254, 0.15); transform: scale(1.05); z-index: 10; }
.price-card.popular:hover { transform: scale(1.08); box-shadow: 0 0 40px rgba(0, 242, 254, 0.3); }
.badge { position: absolute; top: -14px; left: 50%; transform: translateX(-50%); background: linear-gradient(135deg, #00f2fe, #4facfe); color: #000; padding: 6px 16px; border-radius: 20px; font-size: 0.85rem; font-weight: 800; box-shadow: 0 0 15px var(--primary-glow); }
.price-card h3 { font-size: 1.4rem; margin-bottom: 15px; color: var(--white); }
.price { font-size: 2.5rem; font-weight: 700; color: var(--primary-color); margin-bottom: 20px; text-shadow: 0 0 10px var(--primary-glow); }
.price span { font-size: 1rem; color: var(--text-muted); font-weight: normal; text-shadow: none; }
.features-list { list-style: none; margin-bottom: 30px; text-align: left; }
.features-list li { margin-bottom: 12px; color: var(--text-muted); padding-left: 28px; position: relative; font-weight: 300; }
.features-list li::before { content: "⚡"; position: absolute; left: 0; color: var(--primary-color); font-size: 0.9rem; top: 2px; }
.price-card .btn { width: 100%; padding: 14px; }

/* 常见问题 (FAQ) */
.faq-container { max-width: 800px; margin: 0 auto; }
.faq-item { margin-bottom: 16px; padding: 24px; cursor: pointer; }
.faq-item:hover { border-color: var(--primary-color); box-shadow: 0 0 20px rgba(0, 242, 254, 0.1); transform: translateX(5px); }
.faq-item h4 { font-size: 1.1rem; margin-bottom: 10px; color: var(--white); }
.faq-item p { color: var(--text-muted); font-size: 0.95rem; font-weight: 300; }

/* 用户评价 */
.stars { color: #00f2fe; font-size: 1.2rem; margin-bottom: 15px; letter-spacing: 2px; text-shadow: 0 0 5px var(--primary-glow); }
.review-text { font-size: 1rem; color: var(--text-main); margin-bottom: 20px; font-style: italic; font-weight: 300; }
.reviewer { display: flex; align-items: center; gap: 12px; }
.avatar { width: 40px; height: 40px; border-radius: 50%; background: linear-gradient(135deg, #00f2fe, #4facfe); color: #000; display: flex; align-items: center; justify-content: center; font-weight: bold; }
.reviewer-info h5 { font-size: 1rem; color: var(--white); }
.reviewer-info span { font-size: 0.85rem; color: var(--primary-color); }

/* 页脚 */
footer { border-top: 1px solid var(--border-color); padding: 60px 0 30px; text-align: center; margin-top: 60px; background: rgba(5, 5, 15, 0.8); backdrop-filter: blur(10px); }
.footer-nav { display: flex; justify-content: center; gap: 40px; margin-bottom: 30px; }
.footer-nav a { color: var(--text-muted); transition: all 0.3s; position: relative; }
.footer-nav a:hover { color: var(--primary-color); text-shadow: 0 0 8px var(--primary-glow); }
.copyright { font-size: 0.9rem; color: #475569; }

/* 子页面通用 */
.page-header { padding: 100px 20px; text-align: center; border-bottom: 1px solid var(--border-color); background: radial-gradient(circle at 50% 100%, rgba(0, 242, 254, 0.05) 0%, transparent 50%); }
.page-header h1 { font-size: 2.8rem; color: var(--white); text-shadow: 0 0 15px var(--primary-glow); }
.page-content { margin: 40px auto 80px; max-width: 900px; padding: 50px; }
.page-content h2 { font-size: 1.6rem; margin: 30px 0 15px; color: var(--primary-color); }
.page-content p, .page-content ul { color: var(--text-main); margin-bottom: 16px; font-weight: 300; }
.page-content ul { margin-left: 24px; }
.page-content li { margin-bottom: 8px; }
.page-content strong { color: var(--white); font-weight: 600; }

/* 响应式 */
@media (max-width: 768px) {
    .nav-container { flex-direction: column; height: auto; padding: 15px 0; gap: 15px; }
    .nav-links { gap: 15px; flex-wrap: wrap; justify-content: center; }
    .hero { padding: 100px 20px; }
    .hero h1 { font-size: 2.5rem; }
    .hero::before { width: 100vw; height: 100vw; }
    .btn { display: block; width: 100%; padding: 16px; font-size: 1.2rem; margin-bottom: 10px; }
    .btn-alt { margin-bottom: 0; }
    .grid-3, .grid-2 { grid-template-columns: 1fr; }
    .price-card.popular { transform: scale(1); }
    .price-card.popular:hover { transform: translateY(-5px); }
    .footer-nav { flex-direction: column; gap: 20px; }
    .page-content { padding: 30px 20px; margin: 20px auto 40px; }
}


/* --- 修复无障碍与移动端 --- */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary-color);
    color: #000;
    padding: 8px;
    z-index: 9999;
    transition: top 0.2s;
}
.skip-link:focus {
    top: 0;
}

*:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

section[id] {
    scroll-margin-top: 80px;
}

/* 确保按钮最小触控尺寸 */
.btn {
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

/* FAQ Details 样式重构 */
details.faq-item {
    cursor: pointer;
}
details.faq-item summary {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary-color);
    outline: none;
    list-style: none; /* hide default marker */
}
details.faq-item summary::-webkit-details-marker {
    display: none;
}
details.faq-item p {
    margin-top: 15px;
    color: var(--text-muted);
}

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}