/* Shanhuyun Custom CSS - Premium and Dynamic aesthetics */

:root {
    --primary: #ff6b35; /* Orange-Red for Shanhuyun */
    --primary-alt: #e84a27;
    --secondary: #ff9f1c;
    --accent: #ffd166;
    --bg-dark: #0d0e12;
    --bg-card: rgba(30, 32, 40, 0.75);
    --text-light: #fdfdfe;
    --text-dim: #9ca3af;
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-glow: rgba(255, 107, 53, 0.15);
}

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

body {
    font-family: 'Noto Sans SC', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-light);
    line-height: 1.65;
    overflow-x: hidden;
}

/* Dynamic Background Atmosphere */
.bg-glow {
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background: radial-gradient(circle at 15% 50%, rgba(255, 107, 53, 0.1), transparent 45%),
                radial-gradient(circle at 85% 30%, rgba(255, 159, 28, 0.08), transparent 50%);
    z-index: -1;
}

.bg-particles {
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background-image: 
        radial-gradient(rgba(255, 255, 255, 0.08) 1.5px, transparent 1.5px),
        radial-gradient(rgba(255, 107, 53, 0.12) 2px, transparent 2px);
    background-size: 80px 80px, 150px 150px;
    background-position: 0 0, 0 0;
    animation: particleAnimation 100s linear infinite;
}

@keyframes particleAnimation {
    0% { background-position: 0 0, 0 0; }
    100% { background-position: 800px 800px, -750px 750px; }
}

/* Container */
.container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 5%;
}

/* Navigation */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    position: sticky;
    top: 0;
    background: rgba(13, 14, 18, 0.85);
    backdrop-filter: blur(15px);
    z-index: 1000;
    border-bottom: 1px solid var(--glass-border);
}

.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-img {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    object-fit: cover;
}

.logo a {
    font-size: 1.8rem;
    font-weight: 900;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    text-decoration: none;
    letter-spacing: 0.5px;
}

.nav-links {
    display: flex;
    align-items: center;
}

.nav-links a {
    color: var(--text-dim);
    text-decoration: none;
    margin-left: 2rem;
    font-size: 1rem;
    font-weight: 500;
    transition: color 0.3s, transform 0.2s;
}

.nav-links a:hover {
    color: var(--primary);
    transform: translateY(-2px);
}

.nav-links .nav-cta {
    padding: 0.6rem 1.4rem;
    font-size: 0.95rem;
    border-radius: 50px;
    background: linear-gradient(90deg, var(--primary), var(--primary-alt));
    color: #fff;
    margin-left: 2.5rem;
    box-shadow: 0 4px 15px var(--glass-glow);
}

.nav-links .nav-cta:hover {
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 6px 20px var(--glass-glow);
}

/* Hero Section */
.hero {
    min-height: 85vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 6rem 5%;
}

.hero h1 {
    font-size: clamp(2.8rem, 7vw, 4.5rem);
    background: linear-gradient(135deg, #fff 50%, var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1.8rem;
    font-weight: 900;
    letter-spacing: -1px;
}

.hero p {
    font-size: 1.35rem;
    color: var(--text-dim);
    max-width: 850px;
    margin-bottom: 3.5rem;
    line-height: 1.8;
}

.hero-actions {
    display: flex;
    gap: 1.8rem;
}

.cta-button {
    padding: 1.1rem 3rem;
    font-size: 1.15rem;
    font-weight: 800;
    border-radius: 50px;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.primary-btn {
    background: linear-gradient(90deg, var(--primary), var(--primary-alt));
    color: #fff;
    box-shadow: 0 10px 30px rgba(255, 107, 53, 0.35);
}

.primary-btn:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 15px 40px rgba(255, 107, 53, 0.45);
}

.secondary-btn {
    background: rgba(255,255,255,0.05);
    color: #fff;
    border: 1px solid var(--glass-border);
}

.secondary-btn:hover {
    background: rgba(255,255,255,0.1);
    border-color: var(--primary);
    transform: translateY(-4px);
}

/* Features Section */
section {
    padding: 8rem 0;
}

.section-header {
    text-align: center;
    margin-bottom: 5rem;
}

.section-header h2 {
    font-size: 2.8rem;
    margin-bottom: 1.2rem;
    color: #fff;
    font-weight: 800;
}

.section-subtitle {
    font-size: 1.2rem;
    color: var(--text-dim);
    max-width: 750px;
    margin: 0 auto;
}

.grid {
    display: grid;
    gap: 2.5rem;
}

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

.card {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    padding: 3.5rem 2.5rem;
    border-radius: 24px;
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
}

.card:hover {
    transform: translateY(-10px);
    background: rgba(40, 44, 55, 0.9);
    border-color: var(--primary);
    box-shadow: 0 20px 40px rgba(0,0,0,0.3);
}

.card .icon {
    font-size: 3rem;
    margin-bottom: 2rem;
    display: block;
}

.card h3 {
    font-size: 1.6rem;
    margin-bottom: 1.2rem;
    color: #fff;
}

.card p {
    color: var(--text-dim);
    font-size: 1.05rem;
}

/* Pricing Cards */
.pricing-grid {
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    align-items: stretch;
}

.pricing-card {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    border-radius: 32px;
    padding: 4rem 3rem;
    text-align: center;
    display: flex;
    flex-direction: column;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
}

.pricing-card.featured {
    border: 2px solid var(--primary);
    background: radial-gradient(circle at top right, rgba(255, 107, 53, 0.1), transparent 70%), var(--bg-card);
    transform: scale(1.05);
    z-index: 10;
}

.pricing-card:hover {
    transform: translateY(-12px);
    border-color: var(--primary);
}

.pricing-card.featured:hover {
    transform: scale(1.05) translateY(-12px);
}

.badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--primary);
    color: #fff;
    padding: 0.5rem 1.8rem;
    border-radius: 50px;
    font-weight: 800;
    font-size: 0.95rem;
    box-shadow: 0 8px 20px rgba(255, 107, 53, 0.4);
}

.pricing-card h3 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: #fff;
}

.price {
    font-size: 4rem;
    font-weight: 900;
    color: #fff;
    margin-bottom: 2rem;
}

.price span { font-size: 1.5rem; color: var(--text-dim); }
.price em { font-style: normal; font-size: 1.2rem; color: var(--text-dim); }

.plan-features {
    list-style: none;
    text-align: left;
    margin-bottom: 4rem;
    flex-grow: 1;
}

.plan-features li {
    padding: 0.8rem 0;
    color: var(--text-light);
    font-size: 1.05rem;
    display: flex;
    align-items: center;
    gap: 12px;
}

.plan-features li i {
    color: var(--primary);
    font-weight: 900;
}

.price-btn {
    width: 100%;
    padding: 1.2rem;
    border-radius: 16px;
    font-weight: 800;
    text-decoration: none;
    background: rgba(255,255,255,0.06);
    color: #fff;
    border: 1px solid var(--glass-border);
    transition: all 0.3s;
}

.pricing-card.featured .price-btn {
    background: var(--primary);
    border: none;
}

.price-btn:hover {
    background: rgba(255,255,255,0.12);
    border-color: var(--primary);
}

.pricing-card.featured .price-btn:hover {
    background: var(--primary-alt);
    transform: scale(1.02);
}

/* Nodes Section */
.node-grid {
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 2rem;
}

.node-card {
    background: rgba(255,255,255,0.03);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s;
}

.node-card:hover {
    background: rgba(255, 107, 53, 0.05);
    border-color: var(--primary);
}

.node-flag { font-size: 2.5rem; margin-bottom: 1rem; display: block;}
.node-name { font-size: 1.1rem; margin-bottom: 1.2rem; font-weight: 600; color: #fff; }
.latency {
    padding: 0.3rem 1rem;
    border-radius: 50px;
    font-size: 0.9rem;
    font-weight: 800;
}
.latency.low { color: #00ff88; background: rgba(0, 255, 136, 0.1); }
.latency.mid { color: #ffcc00; background: rgba(255, 204, 0, 0.1); }

/* Knowledge Base */
.kb-grid {
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
}
.kb-card {
    padding: 3rem;
    background: var(--bg-card);
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    transition: all 0.3s;
}
.kb-card:hover {
    border-color: var(--primary);
    transform: scale(1.02);
}
.kb-card h3 { margin-bottom: 1.5rem; font-size: 1.5rem; line-height: 1.4; color: #fff;}
.kb-card a { color: inherit; text-decoration: none; }
.kb-card h3 a:hover { color: var(--primary); }
.kb-card p { color: var(--text-dim); margin-bottom: 2rem; font-size: 1.05rem; }
.kb-link { color: var(--primary)!important; font-weight: 800; text-decoration: none; }

/* FAQ */
.faq-grid {
    grid-template-columns: 1fr;
    max-width: 800px;
    margin: 0 auto;
}
.faq-card h3 { font-size: 1.4rem; color: var(--secondary); margin-bottom: 1rem; font-weight: 700;}
.faq-card p { color: var(--text-dim); font-size: 1.1rem; }

/* Footer */
footer {
    border-top: 1px solid var(--glass-border);
    padding: 6rem 0 3rem;
    background: #08090b;
}
.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 4rem;
}
.footer-logo { font-size: 1.8rem; font-weight: 950; color: #fff; margin-bottom: 0.8rem; }
.footer-brand p { color: var(--text-dim); }
.copyright {
    text-align: center;
    color: rgba(255,255,255,0.2);
    font-size: 0.9rem;
    padding-top: 3rem;
    border-top: 1px solid rgba(255,255,255,0.05);
}

@media (max-width: 768px) {
    .nav-links { display: none; }
    .hero h1 { font-size: 3rem; }
    .hero-actions { flex-direction: column; width: 100%; }
    .pricing-card.featured { transform: scale(1); }
    section { padding: 5rem 0; }
}