/* 
   三番云 (sanfancloud.mom) 官方网站样式表
   设计风格：真实天空云朵背景 + 高端毛玻璃化 (Glassmorphism) + 蓝白渐变字体 + 动态漂浮云朵
*/

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;600;800&family=Noto+Sans+SC:wght@300;400;700&display=swap');

:root {
    --primary-color: #228be6;
    --primary-hover: #1c7ed6;
    --primary-light: #e7f5ff;
    --secondary-color: #4dabf7;
    --dark-bg: #0b192c;
    --text-white: #ffffff;
    --text-muted: #d0ebff;
    --text-dark: #1c2e4a;
    --font-sans: 'Outfit', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --transition-speed: 0.3s;
    --border-radius: 16px;
    --glass-bg: rgba(255, 255, 255, 0.12);
    --glass-border: rgba(255, 255, 255, 0.2);
    --glass-shadow: 0 10px 30px 0 rgba(11, 25, 44, 0.15);
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    background: #0f2b48 url('../images/sky_clouds_bg.jpg') no-repeat center center fixed;
    background-size: cover;
    color: var(--text-white);
    min-height: 100vh;
    line-height: 1.6;
    overflow-x: hidden;
    position: relative;
}

/* 背景云雾覆盖层 (加深对比，防止纯白云朵背景影响文字可读性) */
body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, rgba(15, 43, 72, 0.4) 0%, rgba(11, 25, 44, 0.85) 100%);
    z-index: 1;
    pointer-events: none;
}

/* 所有内容容器 */
.app-container {
    position: relative;
    z-index: 2;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* 页面通用布局 */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* 蓝白渐变字体 */
.gradient-text {
    background: linear-gradient(135deg, #ffffff 15%, #90caf9 55%, #1e88e5 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: inline-block;
}

/* 漂浮的真实云朵元素 (CSS动画) */
.cloud-drift-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    pointer-events: none;
    z-index: 1;
}

.drifting-cloud {
    position: absolute;
    background: radial-gradient(circle, rgba(255,255,255,0.4) 0%, rgba(255,255,255,0.1) 60%, rgba(255,255,255,0) 100%);
    border-radius: 50%;
    filter: blur(20px);
    opacity: 0.7;
    animation: drift linear infinite;
}

.cloud-1 {
    width: 350px;
    height: 120px;
    top: 15%;
    left: -350px;
    animation-duration: 80s;
}

.cloud-2 {
    width: 500px;
    height: 180px;
    top: 45%;
    left: -500px;
    animation-duration: 120s;
    animation-delay: -30s;
    opacity: 0.5;
}

.cloud-3 {
    width: 280px;
    height: 90px;
    top: 70%;
    left: -280px;
    animation-duration: 65s;
    animation-delay: -10s;
}

@keyframes drift {
    0% {
        transform: translateX(0);
    }
    100% {
        transform: translateX(calc(100vw + 500px));
    }
}

/* 毛玻璃质感卡片 */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(16px) saturate(180%);
    -webkit-backdrop-filter: blur(16px) saturate(180%);
    border: 1px solid var(--glass-border);
    border-radius: var(--border-radius);
    box-shadow: var(--glass-shadow);
    padding: 30px;
    transition: transform var(--transition-speed) cubic-bezier(0.25, 0.8, 0.25, 1), 
                box-shadow var(--transition-speed) ease,
                border-color var(--transition-speed) ease;
}

.glass-card:hover {
    transform: translateY(-5px);
    border-color: rgba(255, 255, 255, 0.35);
    box-shadow: 0 15px 35px 0 rgba(77, 171, 247, 0.2);
}

/* 导航栏 */
.header {
    background: rgba(11, 25, 44, 0.4);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-white);
}

.brand-cloud-icon {
    font-size: 1.8rem;
    color: var(--secondary-color);
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.95rem;
    transition: color var(--transition-speed) ease;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-white);
}

.nav-cta {
    background: linear-gradient(135deg, #1e88e5 0%, #0d47a1 100%);
    color: var(--text-white) !important;
    padding: 10px 22px;
    border-radius: 50px;
    box-shadow: 0 4px 15px rgba(30, 136, 229, 0.3);
    transition: transform 0.2s ease, box-shadow 0.2s ease !important;
}

.nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(30, 136, 229, 0.45);
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-white);
    font-size: 1.5rem;
    cursor: pointer;
    z-index: 102;
}

/* 首屏 (Hero Section) */
.hero {
    padding: 100px 0 80px;
    text-align: center;
    position: relative;
}

.hero-tag {
    background: rgba(77, 171, 247, 0.15);
    border: 1px solid rgba(77, 171, 247, 0.3);
    padding: 8px 16px;
    border-radius: 50px;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    display: inline-block;
    margin-bottom: 24px;
    color: #a5d8ff;
}

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

.hero p {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto 40px;
}

.cta-group {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 700;
    text-decoration: none;
    transition: all 0.2s ease;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, #1e88e5 0%, #0d47a1 100%);
    color: var(--text-white);
    box-shadow: 0 8px 25px rgba(30, 136, 229, 0.4);
    border: none;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 30px rgba(30, 136, 229, 0.6);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-white);
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(5px);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-3px);
}

/* 特色服务板块 (Features) */
.section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
}

.section-title h2 {
    font-size: 2.2rem;
    font-weight: 800;
    margin-bottom: 15px;
}

.section-title p {
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.feature-card {
    text-align: left;
}

.feature-icon-wrapper {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: rgba(34, 139, 230, 0.15);
    border: 1px solid rgba(34, 139, 230, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* 价格板块 (Pricing) */
.pricing-tabs-wrapper {
    display: flex;
    justify-content: center;
    margin-bottom: 40px;
}

.pricing-tabs {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.1);
    padding: 6px;
    border-radius: 50px;
    display: flex;
    gap: 5px;
}

.pricing-tab {
    background: transparent;
    border: none;
    color: var(--text-muted);
    padding: 10px 24px;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.pricing-tab.active {
    background: var(--primary-color);
    color: var(--text-white);
    box-shadow: 0 4px 15px rgba(34, 139, 230, 0.3);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 15px;
    align-items: stretch;
}

.pricing-card {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 24px 16px;
}

/* 特定卡片高亮 */
.pricing-card.popular {
    border: 2px solid var(--secondary-color);
    transform: scale(1.03);
    position: relative;
}

.pricing-card.popular:hover {
    transform: scale(1.03) translateY(-5px);
}

.popular-badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, #fcc419 0%, #f08c00 100%);
    color: #1c2e4a;
    font-size: 0.75rem;
    font-weight: 800;
    padding: 6px 16px;
    border-radius: 50px;
    box-shadow: 0 4px 10px rgba(252, 196, 25, 0.3);
}

.pricing-card-header {
    text-align: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding-bottom: 25px;
    margin-bottom: 25px;
}

.pricing-name {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.pricing-price {
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1;
    margin-bottom: 5px;
}

.pricing-price span {
    font-size: 1rem;
    font-weight: 400;
    color: var(--text-muted);
}

.pricing-billing {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.pricing-features-list {
    list-style: none;
    margin-bottom: 35px;
    flex-grow: 1;
}

.pricing-features-list li {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
    font-size: 0.95rem;
}

.pricing-features-list li i {
    color: var(--secondary-color);
    font-size: 1rem;
}

.pricing-card .btn {
    width: 100%;
}

/* 用户评价 (Testimonials) */
.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.testimonial-card {
    position: relative;
}

.testimonial-quote {
    font-size: 0.95rem;
    color: var(--text-muted);
    font-style: italic;
    margin-bottom: 20px;
}

.testimonial-user {
    display: flex;
    align-items: center;
    gap: 15px;
}

.user-avatar {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: #1c7ed6;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.2rem;
    color: var(--text-white);
    border: 2px solid rgba(255, 255, 255, 0.3);
}

.user-info h4 {
    font-size: 1rem;
    font-weight: 700;
}

.user-info p {
    font-size: 0.8rem;
    color: var(--secondary-color);
}

.star-rating {
    display: flex;
    gap: 3px;
    color: #fcc419;
    font-size: 0.85rem;
    margin-top: 5px;
}

/* 常见问题 (FAQ) */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.faq-item {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: all var(--transition-speed) ease;
}

.faq-item.active {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(77, 171, 247, 0.4);
}

.faq-question {
    width: 100%;
    background: none;
    border: none;
    padding: 22px;
    text-align: left;
    color: var(--text-white);
    font-size: 1.05rem;
    font-weight: 700;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
}

.faq-question i {
    transition: transform var(--transition-speed) ease;
    color: var(--secondary-color);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    color: var(--text-muted);
    font-size: 0.95rem;
}

.faq-answer-inner {
    padding: 0 22px 22px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

/* 相关文章板块 (Blog Articles) */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.article-card {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.article-meta {
    font-size: 0.8rem;
    color: var(--secondary-color);
    margin-bottom: 10px;
    font-weight: 600;
}

.article-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
    line-height: 1.4;
}

.article-card h3 a {
    text-decoration: none;
    color: var(--text-white);
    transition: color var(--transition-speed) ease;
}

.article-card h3 a:hover {
    color: var(--secondary-color);
}

.article-excerpt {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 20px;
    flex-grow: 1;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.read-more-btn {
    color: var(--secondary-color);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 700;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    transition: gap 0.2s ease;
}

.read-more-btn:hover {
    gap: 10px;
}

/* 文章详情页专用布局 */
.article-page-header {
    padding: 80px 0 40px;
    text-align: center;
    background: rgba(11, 25, 44, 0.4);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.article-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 60px 24px;
}

.article-content {
    font-size: 1.05rem;
    line-height: 1.8;
    color: #e2f1fd;
}

.article-content p {
    margin-bottom: 25px;
    text-align: justify;
}

.article-content h2 {
    font-size: 1.6rem;
    margin: 40px 0 20px;
    color: var(--text-white);
    border-left: 4px solid var(--secondary-color);
    padding-left: 15px;
}

.article-content h3 {
    font-size: 1.3rem;
    margin: 30px 0 15px;
    color: var(--text-white);
}

.article-content ul {
    margin-bottom: 25px;
    padding-left: 20px;
}

.article-content li {
    margin-bottom: 10px;
}

.article-content a {
    color: var(--secondary-color);
    text-decoration: underline;
    transition: color 0.2s ease;
}

.article-content a:hover {
    color: #74c0fc;
}

.keyword-tag {
    background: rgba(77, 171, 247, 0.12);
    border: 1px solid rgba(77, 171, 247, 0.25);
    color: #a5d8ff;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
}

.article-cta-box {
    margin-top: 50px;
    text-align: center;
    border: 2px dashed rgba(77, 171, 247, 0.3);
}

.article-navigation {
    display: flex;
    justify-content: space-between;
    margin-top: 60px;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    flex-wrap: wrap;
    gap: 20px;
}

.article-nav-link {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.95rem;
    max-width: 45%;
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.article-nav-link span {
    font-size: 0.8rem;
    color: var(--secondary-color);
    text-transform: uppercase;
    font-weight: 700;
}

.article-nav-link:hover {
    color: var(--text-white);
}

/* 页脚 (Footer) */
.footer {
    background: rgba(7, 15, 28, 0.95);
    padding: 60px 0 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    margin-top: auto;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column h4 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-column h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 30px;
    height: 2px;
    background: var(--secondary-color);
}

.footer-column p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 15px;
}

.footer-column ul {
    list-style: none;
}

.footer-column ul li {
    margin-bottom: 12px;
}

.footer-column ul li a {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.9rem;
    transition: color var(--transition-speed) ease;
}

.footer-column ul li a:hover {
    color: var(--text-white);
    padding-left: 5px;
    transition: all 0.2s ease;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ==========================================================================
   响应式媒体查询
   ========================================================================== */

@media (max-width: 992px) {
    html {
        font-size: 15px;
    }
    
    .hero h1 {
        font-size: 2.8rem;
    }
    
    .pricing-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
    
    .pricing-card {
        padding: 30px;
    }
    
    .pricing-card.popular {
        transform: none;
    }
    
    .pricing-card.popular:hover {
        transform: translateY(-5px);
    }
}

@media (max-width: 768px) {
    /* 导航栏移动端展示 */
    .mobile-menu-btn {
        display: block;
    }
    
    .nav-links {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 80px);
        background: rgba(11, 25, 44, 0.95);
        backdrop-filter: blur(20px);
        flex-direction: column;
        justify-content: center;
        gap: 40px;
        transition: left 0.4s cubic-bezier(0.77, 0.2, 0.05, 1);
        z-index: 101;
    }
    
    .nav-links.active {
        left: 0;
    }
    
    .nav-links a {
        font-size: 1.2rem;
    }
    
    .hero {
        padding: 60px 0;
    }
    
    .hero h1 {
        font-size: 2.2rem;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    .section {
        padding: 50px 0;
    }
    
    .section-title h2 {
        font-size: 1.8rem;
    }
    
    .cta-group {
        flex-direction: column;
        padding: 0 20px;
    }
    
    .btn {
        width: 100%;
    }
    
    .pricing-grid {
        grid-template-columns: 1fr;
        padding: 0 10px;
    }
    
    .testimonials-grid,
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .article-nav-link {
        max-width: 100%;
        width: 100%;
    }
}