/* 重置与基础设置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

body {
    background-color: #fafafa;
    color: #333;
    line-height: 1.6;
}

/* 导航栏 - 椭圆形悬浮式 */
header {
    position: sticky;
    top: 20px;
    z-index: 1000;
    display: flex;
    justify-content: center;
    padding: 0 5%;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    max-width: 1000px;
    padding: 10px 30px;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: 50px; /* 椭圆形 */
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

.logo {
    font-size: 22px;
    font-weight: 800;
    color: #1a73e8;
    letter-spacing: 1px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: #444;
    font-weight: 600;
    font-size: 0.95rem;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #1a73e8;
}

.btn-nav, .btn-primary, .btn-buy {
    display: inline-block;
    background: #1a73e8;
    color: #fff;
    padding: 10px 24px;
    border-radius: 30px;
    text-decoration: none;
    font-weight: bold;
    transition: all 0.3s ease;
}

.btn-nav:hover, .btn-primary:hover, .btn-buy:hover {
    background: #1557b0;
    box-shadow: 0 4px 15px rgba(26, 115, 232, 0.4);
    transform: translateY(-2px);
}

/* 主视觉区 - 全新居中布局 */
.hero {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 120px 5% 80px;
    background: radial-gradient(circle at top, #e8f0fe 0%, #fafafa 70%);
}

.hero-content {
    max-width: 800px;
    margin-bottom: 50px;
}

.hero-content h1 {
    font-size: 3.5rem;
    color: #202124;
    margin-bottom: 24px;
    line-height: 1.2;
    font-weight: 800;
}

.hero-content h2 {
    font-size: 1.25rem;
    color: #5f6368;
    font-weight: 400;
    margin-bottom: 40px;
}

.hero-animation {
    position: relative;
    width: 100%;
    max-width: 900px;
    height: 250px;
    display: flex;
    justify-content: space-around;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.dynamic-card {
    background: #fff;
    padding: 20px 40px;
    border-radius: 100px;
    box-shadow: 0 10px 30px rgba(26, 115, 232, 0.1);
    font-weight: bold;
    color: #1a73e8;
    animation: float 5s ease-in-out infinite;
}

.card-1 { animation-delay: 0s; }
.card-2 { animation-delay: 1.5s; transform: translateY(20px); }
.card-3 { animation-delay: 3s; }

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-15px); }
    100% { transform: translateY(0px); }
}

/* 核心优势 & 流媒体 */
.features, .media-ai {
    padding: 80px 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.features h3, .media-ai h3, .pricing h3, .articles h3 {
    font-size: 2.2rem;
    margin-bottom: 50px;
    color: #202124;
    text-align: center;
    font-weight: 700;
}

.feature-grid, .media-grid, .pricing-grid, .article-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card, .media-card {
    background: #fff;
    padding: 40px;
    border-radius: 20px;
    border: 1px solid #f1f3f4;
    transition: all 0.3s;
    text-align: left;
}

.feature-card:hover, .media-card:hover {
    box-shadow: 0 10px 40px rgba(0,0,0,0.06);
    transform: translateY(-5px);
}

.feature-card img {
    margin-bottom: 25px;
    width: 48px;
    height: 48px;
    border-radius: 12px;
}

.feature-card h4, .media-card h4 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: #202124;
}

.feature-card p, .media-card p {
    color: #5f6368;
    font-size: 1rem;
}

/* 套餐价格 - 错落布局 */
.pricing {
    padding: 80px 5%;
    background: #f8f9fa;
}

.pricing-grid {
    max-width: 1100px;
    margin: 0 auto;
    align-items: center;
}

.pricing-card {
    background: #fff;
    padding: 40px 30px;
    border-radius: 24px;
    border: 1px solid #eee;
    text-align: center;
    transition: transform 0.3s;
}

.pricing-card.highlight {
    background: #1a73e8;
    color: #fff;
    padding: 60px 30px;
    border: none;
    box-shadow: 0 20px 40px rgba(26, 115, 232, 0.2);
}

.pricing-card h4 {
    font-size: 1.5rem;
    margin-bottom: 15px;
}

.price {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 25px;
}

.pricing-card.highlight .price {
    color: #fff;
}

.pricing-card:not(.highlight) .price {
    color: #202124;
}

.price span {
    font-size: 1.2rem;
    font-weight: 400;
    opacity: 0.7;
}

.pricing-card ul {
    list-style: none;
    margin-bottom: 35px;
    text-align: center;
}

.pricing-card ul li {
    margin-bottom: 15px;
    font-size: 1.05rem;
}

.pricing-card:not(.highlight) ul li {
    color: #5f6368;
}

.pricing-card.highlight .btn-buy {
    background: #fff;
    color: #1a73e8;
}

.pricing-card.highlight .btn-buy:hover {
    background: #f1f3f4;
}

/* 文章图卡 */
.articles {
    padding: 80px 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.article-card {
    background: #fff;
    padding: 25px;
    border-radius: 16px;
    border: 1px solid #f1f3f4;
    transition: all 0.3s ease;
}

.article-card:hover {
    box-shadow: 0 8px 24px rgba(0,0,0,0.06);
}

.article-card h4 {
    margin-bottom: 12px;
    font-size: 1.2rem;
}

.article-card h4 a {
    text-decoration: none;
    color: #202124;
    transition: color 0.2s;
}

.article-card h4 a:hover {
    color: #1a73e8;
}

.article-card p {
    font-size: 0.95rem;
    color: #5f6368;
}

/* FAQ与评价 - 两栏分离 */
.faq-reviews {
    display: flex;
    flex-wrap: wrap;
    gap: 60px;
    padding: 80px 5%;
    max-width: 1200px;
    margin: 0 auto;
}

.faq-section, .reviews-section {
    flex: 1;
    min-width: 300px;
}

.faq-item, .review-item {
    background: #fff;
    padding: 25px;
    border-radius: 16px;
    margin-bottom: 20px;
    border: 1px solid #f1f3f4;
}

.faq-item h4 {
    margin-bottom: 10px;
    color: #202124;
    font-size: 1.15rem;
}

.faq-item p {
    color: #5f6368;
}

.review-item p {
    font-style: italic;
    color: #444;
    font-size: 1.05rem;
}

.review-item span {
    display: block;
    margin-top: 12px;
    font-weight: 600;
    color: #1a73e8;
}

/* 页脚 */
footer {
    background: #202124;
    color: #fff;
    padding: 60px 5% 40px;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.footer-links a {
    color: #9aa0a6;
    text-decoration: none;
    transition: color 0.3s;
    font-size: 0.95rem;
}

.footer-links a:hover {
    color: #fff;
}

/* 响应式 */
@media (max-width: 768px) {
    header { top: 10px; }
    .navbar { padding: 10px 20px; border-radius: 30px; }
    .nav-links { display: none; }
    .hero { padding: 100px 5% 60px; }
    .hero-content h1 { font-size: 2.5rem; }
    .hero-animation { flex-direction: column; height: auto; gap: 20px; }
    .dynamic-card { position: static; width: 100%; max-width: 300px; animation: none; transform: none !important; }
    .pricing-card.highlight { padding: 40px 30px; }
    .faq-reviews { flex-direction: column; gap: 40px; }
}