/* 全局重置与基础设置 */
:root {
    --primary-color: #00FF00; /* 声纳荧光绿 */
    --primary-hover: #00cc00;
    --text-main: #e0f0f0;
    --text-light: #8fa3a3;
    --bg-main: #010611; /* 马里亚纳海沟黑蓝 */
    --bg-light: rgba(5, 11, 26, 0.3); /* 半透明，让气泡透过来 */
    --border-color: #1a2f2f;
    --wetsuit-black: rgba(17, 21, 28, 0.6); /* 半透明潜水服黑 */
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
    font-family: var(--font-family);
    color: var(--text-main);
    background-color: var(--bg-main);
    line-height: 1.6;
    position: relative;
    overflow-x: hidden;
}

/* 保护层级 */
.header, .section, .footer {
    position: relative;
    z-index: 10;
}

#bubbles-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    pointer-events: none;
}

a {
    text-decoration: none;
    color: var(--primary-color);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
    z-index: 2;
}

.section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 32px;
    margin-bottom: 50px;
    color: var(--text-main);
    text-shadow: 0 0 10px rgba(0,255,0,0.3);
}

.bg-light {
    background-color: var(--bg-light);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(3px); /* 增加深海朦胧感 */
}

/* 按钮通用样式 */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn-primary {
    background-color: transparent;
    border-color: var(--primary-color);
    color: var(--primary-color);
    box-shadow: 0 0 10px rgba(0,255,0,0.2), inset 0 0 10px rgba(0,255,0,0.1);
}

.btn-primary:hover {
    background-color: var(--primary-color);
    color: #000;
    box-shadow: 0 0 20px rgba(0,255,0,0.6);
}

.btn-outline {
    background-color: transparent;
    border-color: var(--text-light);
    color: var(--text-light);
}

.btn-outline:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    box-shadow: 0 0 15px rgba(0,255,0,0.3);
}

.btn-large {
    padding: 16px 36px;
    font-size: 18px;
    border-radius: 50px;
}

.btn-large:hover {
    transform: translateY(-2px);
}

/* 导航栏 */
.header {
    background-color: rgba(1, 6, 17, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,255,0,0.2);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 24px;
    font-weight: 800;
    color: var(--primary-color);
    text-shadow: 0 0 8px rgba(0,255,0,0.5);
}

.logo span {
    font-size: 16px;
    color: var(--text-light);
    font-weight: 600;
    margin-left: 5px;
    text-shadow: none;
}

/* 主导航栏 */
.main-nav {
    display: flex;
    gap: 24px;
}

.main-nav a {
    color: var(--text-main);
    font-weight: 500;
    font-size: 16px;
    transition: color 0.3s, text-shadow 0.3s;
}

.main-nav a:hover {
    color: var(--primary-color);
    text-shadow: 0 0 8px rgba(0,255,0,0.5);
}

/* 主视觉区 (Hero) */
.hero {
    background: radial-gradient(circle at center, #05181a 0%, #010611 100%);
    padding: 120px 0;
    text-align: left;
    position: relative;
    overflow: hidden;
}

.hero-content {
    max-width: 650px;
    margin: 0; /* 靠左对齐，不居中 */
    position: relative;
    z-index: 2;
}

.headline {
    font-size: 48px;
    font-weight: 800;
    margin-bottom: 20px;
    line-height: 1.2;
    color: #fff;
    text-shadow: 0 0 5px #00ff00;
    animation: waterRipple 4s infinite alternate ease-in-out;
}

@keyframes waterRipple {
    0% { filter: blur(0px) hue-rotate(0deg); transform: scale(1); }
    50% { filter: blur(1px) hue-rotate(10deg); transform: scale(1.01) skewX(1deg); }
    100% { filter: blur(0px) hue-rotate(-10deg); transform: scale(1); }
}

.sub-headline {
    font-size: 20px;
    color: var(--text-light);
    margin-bottom: 40px;
}

.hero-duck {
    position: absolute;
    left: 50%;
    margin-left: 100px; /* 固定在中心偏右，再宽的屏幕也不会跑太远 */
    top: 50%;
    transform: translateY(-50%);
    width: 350px;
    height: 350px;
    z-index: 1;
    animation: floatDuck 6s ease-in-out infinite;
    pointer-events: none;
}

@keyframes floatDuck {
    0%, 100% { transform: translateY(-50%) rotate(0deg); }
    50% { transform: translateY(-55%) rotate(2deg); }
}

/* 网格布局 */
.grid {
    display: grid;
    gap: 30px;
}

/* 核心优势卡片 */
.features-grid {
    grid-template-columns: repeat(3, 1fr);
}

.card {
    background: var(--wetsuit-black);
    padding: 40px 30px;
    border-radius: 50%; /* Like a sonar display */
    border: 4px solid var(--border-color);
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
    box-shadow: inset 0 0 20px rgba(0,0,0,0.8), 0 10px 20px rgba(0,0,0,0.5);
    position: relative;
    backdrop-filter: blur(5px);
}

.card::before {
    content: '';
    position: absolute;
    top: 30px; right: 40px;
    width: 8px; height: 8px;
    background: var(--primary-color);
    border-radius: 50%;
    box-shadow: 0 0 10px var(--primary-color);
    animation: blinkLight 2s infinite;
}

@keyframes blinkLight { 
    0%, 100% { opacity: 1; } 
    50% { opacity: 0.3; } 
}

.card:hover {
    transform: translateY(-5px);
    border-color: rgba(0,255,0,0.4);
    box-shadow: inset 0 0 20px rgba(0,255,0,0.1), 0 10px 20px rgba(0,0,0,0.5);
}

.card-icon {
    font-size: 48px;
    margin-bottom: 20px;
    filter: drop-shadow(0 0 5px rgba(0,255,0,0.5));
}

.card h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: #fff;
}

.card p {
    color: var(--text-light);
    font-size: 14px;
}

/* 声纳雷达背景特效 */
.features {
    position: relative;
    overflow: hidden;
}

.sonar-bg {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 800px;
    height: 800px;
    transform: translate(-50%, -50%);
    border-radius: 50%;
    border: 1px solid rgba(0, 255, 0, 0.1);
    z-index: 0;
    pointer-events: none;
}

.sonar-bg::after {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    border-radius: 50%;
    background: conic-gradient(from 0deg, transparent 70%, rgba(0,255,0,0.15) 100%);
    animation: sonarSweep 4s linear infinite;
}

@keyframes sonarSweep {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 流媒体与AI支持 */
.sa-grid {
    grid-template-columns: repeat(2, 1fr);
}

.sa-card {
    background: var(--wetsuit-black);
    border-radius: 12px;
    padding: 40px;
    box-shadow: inset 0 0 15px rgba(0,0,0,0.8);
    border: 1px solid var(--border-color);
    backdrop-filter: blur(5px);
}

.sa-content h3 {
    font-size: 24px;
    margin-bottom: 15px;
    color: #fff;
}

.sa-content p {
    color: var(--text-light);
}

/* 套餐价格表 (3D Submarine Hatch) */
.pricing-table {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    align-items: center;
    perspective: 1500px;
}

.pricing-card {
    background: var(--wetsuit-black);
    border: 4px solid #1a2f2f;
    border-radius: 20px;
    padding: 40px 30px;
    text-align: center;
    position: relative;
    transform-style: preserve-3d;
    transition: transform 0.2s ease, border-color 0.3s; /* Reduced transition time for smoother JS follow */
    box-shadow: inset 0 0 30px rgba(0,0,0,0.9), 0 15px 30px rgba(0,0,0,0.7);
    backdrop-filter: blur(5px);
}

.pricing-card::after {
    content: '';
    position: absolute;
    top: 15px; left: 15px; right: 15px; bottom: 15px;
    border: 2px dashed rgba(255,255,255,0.05);
    border-radius: 12px;
    pointer-events: none;
    transform: translateZ(5px);
}

.pricing-card.featured {
    border: 4px solid var(--primary-color);
    box-shadow: inset 0 0 30px rgba(0,255,0,0.1), 0 15px 40px rgba(0,255,0,0.2);
    transform: translateZ(10px);
}

.badge {
    position: absolute;
    top: -14px;
    left: 50%;
    transform: translateX(-50%) translateZ(20px);
    background: var(--bg-main);
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
    padding: 4px 15px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: bold;
    box-shadow: 0 0 10px rgba(0,255,0,0.3);
    letter-spacing: 1px;
}

.pricing-card h3 {
    font-size: 24px;
    margin-bottom: 15px;
    color: #fff;
    text-transform: uppercase;
    letter-spacing: 2px;
    transform: translateZ(30px);
}

.price {
    font-size: 40px;
    font-weight: 800;
    color: var(--primary-color);
    margin-bottom: 25px;
    text-shadow: 0 0 10px rgba(0,255,0,0.5);
    transform: translateZ(40px);
}

.price span {
    font-size: 16px;
    color: var(--text-light);
    font-weight: normal;
    text-shadow: none;
}

.pricing-features {
    list-style: none;
    margin-bottom: 30px;
    text-align: left;
    transform: translateZ(20px);
}

.pricing-features li {
    padding: 10px 0;
    border-bottom: 1px solid rgba(255,255,255,0.05);
    color: var(--text-main);
    font-size: 14px;
}

.pricing-card .btn {
    width: 100%;
    transform: translateZ(35px);
}

/* 用户评价 */
.reviews-grid {
    grid-template-columns: repeat(3, 1fr);
}

.review-card {
    background: var(--wetsuit-black);
    padding: 30px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    position: relative;
    backdrop-filter: blur(5px);
}

.review-card::before {
    content: '"';
    position: absolute;
    top: 10px;
    right: 20px;
    font-size: 60px;
    color: rgba(255,255,255,0.05);
    font-family: serif;
}

.review-text {
    font-style: italic;
    color: var(--text-main);
    margin-bottom: 20px;
}

.review-author {
    font-weight: bold;
    color: var(--primary-color);
}

/* FAQ 常见问题 */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    margin-bottom: 25px;
    padding-bottom: 25px;
    border-bottom: 1px solid var(--border-color);
}

.faq-item h4 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--text-main);
}

.faq-item p {
    color: var(--text-light);
}

/* 底部区域 */
.footer {
    background-color: #000;
    color: #fff;
    padding: 50px 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
}

.footer-links {
    margin-bottom: 30px;
}

.footer-links a {
    color: #aaa;
    margin: 0 15px;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--primary-color);
    text-shadow: 0 0 5px rgba(0,255,0,0.5);
}

.footer-copy {
    color: #444;
    font-size: 14px;
}

/* 响应式媒体查询 (移动端适配) */
@media screen and (max-width: 768px) {
    .header-inner {
        flex-direction: column;
        height: auto;
        padding: 15px 0;
        gap: 15px;
    }
    
    .main-nav {
        flex-wrap: wrap;
        justify-content: center;
        gap: 12px;
        margin-bottom: 10px;
    }

    .section {
        padding: 50px 0;
    }
    
    .hero {
        text-align: center;
        padding: 80px 0;
    }

    .hero-content {
        margin: 0 auto;
    }

    .hero-duck {
        display: none; /* Mobile hides the duck SVG to keep it clean */
    }

    .headline {
        font-size: 32px;
    }
    
    .sub-headline {
        font-size: 16px;
    }

    .features-grid, .sa-grid, .pricing-table, .reviews-grid {
        grid-template-columns: 1fr;
    }
    
    .card {
        border-radius: 12px; /* Remove circle shape on mobile for space */
    }

    .pricing-card.featured {
        transform: scale(1);
    }
    
    .btn {
        padding: 15px 20px;
        font-size: 16px;
    }

    .btn-large {
        width: 100%;
    }
    
    .footer-links a {
        display: block;
        margin: 15px 0;
    }
}

/* -----------------------
   Article SEO Enhancements
------------------------ */
.article-enhancements {
    margin-top: 50px;
    border-top: 1px dashed var(--border-color);
    padding-top: 30px;
}
.article-enhancements h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 1.3rem;
}
.article-internal-links {
    background: rgba(5, 11, 26, 0.4);
    border-left: 4px solid var(--primary-color);
    padding: 20px;
    border-radius: 4px;
    margin-bottom: 40px;
}
.article-internal-links ul {
    list-style: none;
    padding: 0;
    margin: 0;
}
.article-internal-links li {
    margin-bottom: 12px;
}
.article-internal-links li a {
    color: #fff;
    text-decoration: none;
    transition: color 0.3s;
}
.article-internal-links li a:hover {
    color: var(--primary-color);
    text-decoration: underline;
}
.article-faq .faq-item {
    background: var(--wetsuit-black);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 15px;
}
.article-faq .faq-item h4 {
    color: #fff;
    margin-top: 0;
    margin-bottom: 10px;
    font-size: 1.1rem;
}
.article-faq .faq-item p {
    margin: 0;
    color: var(--text-light);
}
.article-faq .faq-item p strong {
    color: var(--primary-color);
}