/* assets/css/style.css */
:root {
    --primary-bg: #000000;
    --text-primary: #ffffff;
    --text-secondary: #aaaaaa;
    --accent-color: #3b82f6; /* A refined blue for accents */
    --accent-hover: #2563eb;
    --glass-bg: rgba(20, 20, 20, 0.6);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-hover: rgba(40, 40, 40, 0.8);
    --font-kaiti: "KaiTi", "STKaiti", "楷体", "STSong", "宋体", serif;
}

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

body {
    font-family: var(--font-kaiti);
    background-color: var(--primary-bg);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    scroll-behavior: smooth;
}

/* Background Image styling (Blue Sky & White Clouds) */
.bg-image {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: url('https://images.unsplash.com/photo-1501630834273-4b5604d2ee31?auto=format&fit=crop&q=80&w=2560') no-repeat center center/cover;
    z-index: -1;
    opacity: 0.85; /* Increased opacity for bright sky */
}

/* Added an overlay to ensure text readability over the crisp image */
.bg-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.4); /* Dark semi-transparent overlay */
    z-index: -1;
}

/* Minimalist Navigation */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--glass-border);
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    letter-spacing: 2px;
    color: #fff;
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 1.1rem;
    transition: color 0.3s ease;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: width 0.3s ease;
}

.nav-links a:hover {
    color: var(--accent-color);
}

.nav-links a:hover::after {
    width: 100%;
}

/* Common Section Styles */
section {
    padding: 6rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
    position: relative;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    letter-spacing: 2px;
    font-weight: normal;
}

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 0 2rem;
    padding-top: 80px;
}

.hero-content {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
    padding: 4rem;
    border-radius: 20px;
    max-width: 800px;
    animation: fadeInDown 1s cubic-bezier(0.16, 1, 0.3, 1);
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    font-weight: normal;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
}

.cta-button {
    display: inline-block;
    padding: 1rem 3rem;
    background: var(--accent-color);
    color: #fff;
    text-decoration: none;
    border-radius: 30px;
    font-size: 1.2rem;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.cta-button:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.5);
}

/* Features Grid (Core Advantages) */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    padding: 2.5rem;
    border-radius: 15px;
    text-align: center;
    transition: all 0.4s ease;
    cursor: default;
}

.feature-card:hover {
    transform: translateY(-10px);
    background: var(--glass-hover);
    border-color: rgba(255, 255, 255, 0.2);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.feature-icon {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1.5rem;
}

.feature-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

/* Pricing Grid (套餐价格 - 图1复刻) */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.pricing-card {
    background: #fff;
    color: #333;
    border-radius: 10px;
    overflow: hidden;
    transition: transform 0.3s ease;
}

.pricing-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(255, 255, 255, 0.1);
}

.pricing-header {
    background: #2b85e4; /* Blue matching 图1 */
    color: #fff;
    padding: 2rem 0;
    text-align: center;
}

.pricing-price {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.pricing-plan {
    font-size: 1.2rem;
    opacity: 0.9;
}

.pricing-features {
    padding: 2rem;
    list-style: none;
}

.pricing-features li {
    padding: 0.8rem 0;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    color: #666;
    border-bottom: 1px solid #eee;
}
.pricing-features li:last-child {
    border-bottom: none;
}

.pricing-features li i {
    color: #2b85e4;
    margin-top: 5px;
}

/* Network Status (网络状态 - 图2复刻) */
.network-notice {
    background: rgba(200, 150, 0, 0.1);
    border: 1px solid rgba(200, 150, 0, 0.3);
    color: #ffd700;
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 2rem;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.network-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.network-card {
    background: #1a1a1a;
    border: 1px solid #333;
    border-radius: 12px;
    padding: 1.5rem;
}

.network-city {
    font-size: 1.5rem;
    font-weight: bold;
    margin-bottom: 0.2rem;
}

.network-subtitle {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

.network-item {
    display: flex;
    justify-content: space-between;
    padding: 0.8rem 0;
    border-bottom: 1px solid #2a2a2a;
}
.network-item:last-child {
    border-bottom: none;
}

.network-dest {
    color: #aaa;
}

.latency-green { color: #00ff00; font-weight: bold; }
.latency-yellow { color: #ffcc00; font-weight: bold; }

/* Articles Grid */
.article-meta {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 2.5rem;
    margin-top: -1rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid var(--glass-border);
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

@media (max-width: 900px) {
    .articles-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .articles-grid {
        grid-template-columns: 1fr;
    }
}

.article-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    padding: 1.5rem;
    border-radius: 10px;
    text-decoration: none;
    color: #fff;
    transition: all 0.3s ease;
}

.article-card:hover {
    background: var(--glass-hover);
    border-color: var(--accent-color);
}

.article-title {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.article-date {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* Footer */
footer {
    text-align: center;
    padding: 3rem 2rem;
    border-top: 1px solid var(--glass-border);
    background: rgba(0,0,0,0.8);
    margin-top: 4rem;
}

/* Animations */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.animate-on-scroll.is-visible {
    opacity: 1;
    transform: translateY(0);
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}