/* CSS Design System for 熊猫Cloud Landing Page */
:root {
    --bg-dark: #080c14;
    --bg-card: #111827;
    --bg-card-hover: #1f2937;
    --text-main: #f3f4f6;
    --text-muted: #9ca3af;
    --cyan-glow: #06b6d4;
    --cyan-accent: #22d3ee;
    --green-glow: #10b981;
    --green-accent: #34d399;
    --orange-glow: #f97316;
    --orange-accent: #fb923c;
    --red-accent: #ef4444;
    --border-color: rgba(255, 255, 255, 0.1);
    --border-glow: rgba(34, 211, 238, 0.4);
    --font-family: 'Plus Jakarta Sans', 'Noto Sans SC', sans-serif;
}

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

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

/* Neon Grid Background (Matching Figure 1 style) */
.grid-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-image: 
        linear-gradient(to right, rgba(34, 211, 238, 0.05) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(34, 211, 238, 0.05) 1px, transparent 1px);
    background-size: 40px 40px;
    z-index: -2;
    pointer-events: none;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header & Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(8, 12, 20, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 15px 0;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: #fff;
    font-size: 1.4rem;
    font-weight: 800;
}

.logo-icon {
    font-size: 1.8rem;
}

.logo-badge {
    font-size: 0.75rem;
    background: linear-gradient(135deg, var(--cyan-glow), var(--green-glow));
    color: #000;
    padding: 2px 8px;
    border-radius: 12px;
    font-weight: 700;
    vertical-align: middle;
}

.nav-links {
    display: flex;
    gap: 25px;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.3s;
}

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

.nav-actions {
    display: flex;
    gap: 12px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 10px 22px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 700;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, #06b6d4, #10b981);
    color: #000;
    box-shadow: 0 0 15px rgba(6, 182, 212, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 25px rgba(6, 182, 212, 0.7);
}

.pulse-btn {
    animation: pulseGlow 2s infinite alternate;
}

@keyframes pulseGlow {
    0% { box-shadow: 0 0 12px rgba(6, 182, 212, 0.4); }
    100% { box-shadow: 0 0 24px rgba(16, 185, 129, 0.8); }
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border-glow);
    color: var(--cyan-accent);
}

.btn-outline:hover {
    background: rgba(34, 211, 238, 0.1);
    color: #fff;
}

.btn-secondary {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: #fff;
}

.btn-secondary:hover {
    background: var(--bg-card-hover);
    border-color: var(--cyan-accent);
}

.btn-lg {
    padding: 14px 32px;
    font-size: 1.1rem;
}

/* Typography Helpers */
.neon-text-cyan {
    color: var(--cyan-accent);
    text-shadow: 0 0 12px rgba(34, 211, 238, 0.6);
}

.neon-text-green {
    color: var(--green-accent);
    text-shadow: 0 0 12px rgba(52, 211, 153, 0.6);
}

.neon-text-red {
    color: var(--red-accent);
    text-shadow: 0 0 12px rgba(239, 68, 68, 0.6);
}

/* Section Shared */
section {
    padding: 90px 0;
}

.section-title {
    font-size: 2.2rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 12px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.05rem;
    margin-bottom: 50px;
}

/* Hero Section */
.hero-section {
    padding-top: 170px;
    padding-bottom: 100px;
    text-align: center;
    position: relative;
}

.hero-badge {
    display: inline-block;
    background: rgba(6, 182, 212, 0.12);
    border: 1px solid var(--cyan-accent);
    color: var(--cyan-accent);
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 25px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.25;
    margin-bottom: 25px;
    letter-spacing: -1px;
}

.hero-desc {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 750px;
    margin: 0 auto 40px auto;
}

.hero-btns {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 60px;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    background: rgba(17, 24, 39, 0.7);
    border: 1px solid var(--border-color);
    backdrop-filter: blur(10px);
    padding: 30px;
    border-radius: 16px;
}

.stat-num {
    display: block;
    font-size: 2.2rem;
    font-weight: 800;
    color: var(--cyan-accent);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* Feature Cards */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 30px;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--cyan-accent);
    box-shadow: 0 10px 25px rgba(6, 182, 212, 0.15);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 10px;
    color: #fff;
}

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

/* Pricing Grid (Matching Figure 2 mockup) */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
    align-items: stretch;
}

.pricing-card {
    background: #111622;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 40px 30px;
    display: flex;
    flex-direction: column;
    position: relative;
    transition: all 0.3s ease;
}

.pricing-card:hover {
    border-color: var(--orange-glow);
}

.pricing-card.featured {
    background: #151c2e;
    border: 2px solid var(--orange-accent);
    box-shadow: 0 0 30px rgba(249, 115, 22, 0.25);
    transform: scale(1.03);
}

.popular-badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--orange-accent);
    color: #000;
    font-weight: 800;
    font-size: 0.85rem;
    padding: 4px 18px;
    border-radius: 20px;
}

.plan-name {
    font-size: 1.5rem;
    text-align: center;
    color: #fff;
    margin-bottom: 20px;
}

.plan-price {
    text-align: center;
    font-size: 3rem;
    font-weight: 800;
    color: var(--green-accent);
    margin-bottom: 30px;
}

.plan-price .currency {
    font-size: 1.8rem;
    vertical-align: super;
}

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

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

.plan-features li {
    padding: 10px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: #d1d5db;
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.plan-features .check {
    color: var(--green-accent);
    font-weight: bold;
}

.btn-primary-plan {
    display: block;
    width: 100%;
    text-align: center;
    background: var(--orange-accent);
    color: #000;
    padding: 14px 0;
    border-radius: 10px;
    font-weight: 800;
    text-decoration: none;
    font-size: 1.05rem;
    box-shadow: 0 4px 15px rgba(249, 115, 22, 0.4);
    transition: all 0.3s;
}

.btn-primary-plan:hover {
    background: #ea580c;
    color: #fff;
}

.btn-outline-plan {
    display: block;
    width: 100%;
    text-align: center;
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    padding: 14px 0;
    border-radius: 10px;
    font-weight: 700;
    text-decoration: none;
    font-size: 1rem;
    transition: all 0.3s;
}

.btn-outline-plan:hover {
    border-color: #fff;
    background: rgba(255, 255, 255, 0.05);
}

/* Tutorial Tabs */
.tutorial-tabs {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.tutorial-tabs .tab {
    padding: 12px 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s;
}

.tutorial-tabs .tab.active, .tutorial-tabs .tab:hover {
    background: var(--cyan-glow);
    color: #000;
    border-color: var(--cyan-accent);
}

.tutorial-box {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 35px;
    max-width: 800px;
    margin: 0 auto;
}

.step-list {
    padding-left: 20px;
}

.step-list li {
    margin-bottom: 18px;
    font-size: 1.05rem;
}

/* Troubleshoot Grid */
.trouble-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.trouble-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 25px;
    border-radius: 12px;
}

.trouble-card h4 {
    color: var(--cyan-accent);
    margin-bottom: 10px;
    font-size: 1.1rem;
}

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

/* FAQ Section */
.faq-list {
    max-width: 850px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    margin-bottom: 15px;
    padding: 20px 25px;
}

.faq-question {
    font-size: 1.1rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 8px;
}

.faq-answer {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* Articles Grid */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 25px;
}

.article-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 14px;
    padding: 25px;
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.article-card:hover {
    transform: translateY(-5px);
    border-color: var(--green-accent);
    box-shadow: 0 10px 25px rgba(16, 185, 129, 0.15);
}

.article-tag {
    display: inline-block;
    align-self: flex-start;
    background: rgba(16, 185, 129, 0.15);
    color: var(--green-accent);
    font-size: 0.8rem;
    padding: 4px 10px;
    border-radius: 6px;
    margin-bottom: 12px;
    font-weight: 600;
}

.article-card h3 {
    font-size: 1.15rem;
    color: #fff;
    margin-bottom: 10px;
    line-height: 1.4;
}

.article-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Article Page Specific Layout */
.article-page {
    padding-top: 140px;
    padding-bottom: 80px;
}

.article-container {
    max-width: 850px;
    margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 45px;
}

.article-header {
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 25px;
    margin-bottom: 35px;
}

.article-meta {
    display: flex;
    gap: 15px;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.article-title-main {
    font-size: 2.2rem;
    font-weight: 800;
    line-height: 1.3;
    color: #fff;
}

.article-body {
    font-size: 1.05rem;
    color: #d1d5db;
    line-height: 1.85;
}

.article-body h2 {
    color: var(--cyan-accent);
    font-size: 1.5rem;
    margin: 35px 0 15px 0;
    padding-bottom: 8px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.article-body h3 {
    color: var(--green-accent);
    font-size: 1.25rem;
    margin: 25px 0 12px 0;
}

.article-body p {
    margin-bottom: 18px;
}

.article-body ul, .article-body ol {
    margin-bottom: 20px;
    padding-left: 25px;
}

.article-body li {
    margin-bottom: 8px;
}

.cta-box {
    background: linear-gradient(135deg, rgba(6, 182, 212, 0.15), rgba(16, 185, 129, 0.15));
    border: 1px solid var(--cyan-accent);
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    margin: 40px 0;
}

.cta-box h3 {
    font-size: 1.4rem;
    color: #fff;
    margin-bottom: 10px;
}

.cta-box p {
    color: var(--text-muted);
    margin-bottom: 20px;
}

.article-faq {
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
}

/* Footer */
.footer {
    background: #05080e;
    border-top: 1px solid var(--border-color);
    padding: 60px 0 30px 0;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand p {
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: 12px;
}

.copyright {
    margin-top: 20px;
    font-size: 0.85rem;
}

.footer-links h4 {
    color: #fff;
    margin-bottom: 18px;
}

.footer-links a {
    display: block;
    color: var(--text-muted);
    text-decoration: none;
    margin-bottom: 10px;
    font-size: 0.9rem;
    transition: color 0.3s;
}

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

/* Responsive */
@media (max-width: 992px) {
    .pricing-grid {
        grid-template-columns: 1fr;
    }
    .pricing-card.featured {
        transform: none;
    }
    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 2.4rem;
    }
    .nav-links {
        display: none;
    }
}