/* ==========================================================================
   Cocoduck.lol - 简洁科技黄 (Tech Yellow Design System)
   Font Family: KaiTi ("楷体", "STKaiti", serif) - Bold, Prominent, Legible
   ========================================================================== */

:root {
    --bg-main: #0b0e14;
    --bg-surface: #121722;
    --bg-card: rgba(20, 26, 38, 0.85);
    --bg-card-hover: rgba(28, 36, 52, 0.95);
    
    /* Tech Yellow Palette */
    --primary-yellow: #fbbf24;
    --primary-yellow-hover: #f59e0b;
    --yellow-dark: #d97706;
    --yellow-glow: rgba(251, 191, 36, 0.35);
    --yellow-light: #fef08a;
    --gold-border: rgba(245, 158, 11, 0.35);
    
    /* Blue Accent for Pricing Cards (as seen in screenshot reference) */
    --brand-blue: #2563eb;
    --brand-blue-hover: #1d4ed8;
    --brand-blue-glow: rgba(37, 99, 235, 0.4);
    
    /* Text colors */
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --text-dark: #0f172a;
    
    /* Base Fonts */
    --font-kaiti: "STKaiti", "楷体", "KaiTi", "Microsoft YaHei", serif, sans-serif;
    --font-code: "Fira Code", "Courier New", monospace;
    
    /* Transitions & Shadows */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-yellow: 0 0 25px rgba(251, 191, 36, 0.25);
    --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 30px;
}

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

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

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    font-family: var(--font-kaiti);
    line-height: 1.7;
    overflow-x: hidden;
    position: relative;
    -webkit-font-smoothing: antialiased;
}

/* Background Canvas & Effects */
#particle-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    pointer-events: none;
}

.bg-glow-top {
    position: absolute;
    top: -150px;
    left: 50%;
    transform: translateX(-50%);
    width: 800px;
    height: 500px;
    background: radial-gradient(circle, rgba(251, 191, 36, 0.15) 0%, rgba(11, 14, 20, 0) 70%);
    z-index: -1;
    pointer-events: none;
}

.container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Typography Styles */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-kaiti);
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 0.5px;
}

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

a:hover {
    color: var(--yellow-light);
}

.highlight-yellow {
    color: var(--primary-yellow);
    text-shadow: 0 0 10px rgba(251, 191, 36, 0.3);
}

.section-title {
    text-align: center;
    font-size: 2.4rem;
    margin-bottom: 12px;
    position: relative;
    display: inline-block;
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.15rem;
    max-width: 700px;
    margin: 0 auto 50px auto;
}

.title-wrapper {
    text-align: center;
    margin-bottom: 40px;
}

.badge-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(251, 191, 36, 0.12);
    border: 1px solid var(--gold-border);
    color: var(--primary-yellow);
    border-radius: 50px;
    font-size: 0.95rem;
    font-weight: bold;
    margin-bottom: 15px;
    box-shadow: 0 0 15px rgba(251, 191, 36, 0.15);
}

/* Header & Sticky Navbar */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(11, 14, 20, 0.88);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(251, 191, 36, 0.15);
    padding: 16px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--text-primary);
}

.logo-icon {
    width: 38px;
    height: 38px;
    background: linear-gradient(135deg, var(--primary-yellow), var(--yellow-dark));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-dark);
    font-size: 1.4rem;
    box-shadow: 0 0 15px rgba(251, 191, 36, 0.4);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 28px;
    align-items: center;
}

.nav-link {
    color: var(--text-secondary);
    font-size: 1.1rem;
    font-weight: 600;
    position: relative;
    padding: 6px 0;
}

.nav-link:hover, .nav-link.active {
    color: var(--primary-yellow);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-yellow);
    transition: var(--transition);
    border-radius: 2px;
}

.nav-link:hover::after, .nav-link.active::after {
    width: 100%;
}

.btn-nav {
    padding: 8px 22px;
    background: linear-gradient(135deg, var(--primary-yellow), var(--yellow-dark));
    color: var(--text-dark);
    font-weight: bold;
    border-radius: 50px;
    box-shadow: 0 0 15px rgba(251, 191, 36, 0.3);
}

.btn-nav:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 25px rgba(251, 191, 36, 0.6);
    color: var(--text-dark);
}

/* Mobile Nav Toggle */
.mobile-toggle {
    display: none;
    font-size: 1.8rem;
    color: var(--primary-yellow);
    cursor: pointer;
}

/* Hero Section */
.hero {
    padding: 90px 0 60px 0;
    position: relative;
}

.hero-grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
    align-items: center;
}

.hero-content h1 {
    font-size: 3.2rem;
    line-height: 1.25;
    margin-bottom: 20px;
}

.hero-desc {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 35px;
    max-width: 620px;
}

.hero-actions {
    display: flex;
    gap: 20px;
    align-items: center;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.btn-primary {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 15px 36px;
    background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
    color: #0b0e14;
    font-size: 1.2rem;
    font-weight: bold;
    border-radius: var(--radius-md);
    box-shadow: 0 0 25px rgba(251, 191, 36, 0.4);
    cursor: pointer;
    border: none;
    transition: var(--transition);
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 0 35px rgba(251, 191, 36, 0.7);
    color: #0b0e14;
}

.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 30px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--gold-border);
    color: var(--text-primary);
    font-size: 1.1rem;
    font-weight: bold;
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.btn-secondary:hover {
    background: rgba(251, 191, 36, 0.15);
    border-color: var(--primary-yellow);
    color: var(--primary-yellow);
    transform: translateY(-2px);
}

.hero-stats {
    display: flex;
    gap: 30px;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.stat-item h3 {
    font-size: 1.8rem;
    color: var(--primary-yellow);
}

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

/* Hero Tech Widget Box */
.hero-widget {
    background: var(--bg-card);
    border: 1px solid var(--gold-border);
    border-radius: var(--radius-lg);
    padding: 24px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4);
    position: relative;
    overflow: hidden;
}

.hero-widget::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-yellow), var(--yellow-dark));
}

.widget-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.widget-title {
    font-size: 1.1rem;
    font-weight: bold;
    display: flex;
    align-items: center;
    gap: 8px;
}

.ping-indicator {
    display: inline-block;
    width: 10px;
    height: 10px;
    background: #10b981;
    border-radius: 50%;
    box-shadow: 0 0 10px #10b981;
    animation: pulsePing 1.8s infinite;
}

@keyframes pulsePing {
    0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
    70% { transform: scale(1.1); box-shadow: 0 0 0 10px rgba(16, 185, 129, 0); }
    100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.node-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.node-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 14px;
    background: rgba(0, 0, 0, 0.25);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.node-info {
    display: flex;
    align-items: center;
    gap: 10px;
}

.node-flag {
    font-size: 1.2rem;
}

.node-name {
    font-size: 0.95rem;
    font-weight: bold;
}

.node-ms {
    color: #10b981;
    font-weight: bold;
    font-size: 0.95rem;
    font-family: var(--font-code);
}

/* Core Advantages Section (核心优势) */
.advantages {
    padding: 80px 0;
    position: relative;
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 25px;
}

.adv-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: 32px 26px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.adv-card:hover {
    transform: translateY(-6px);
    border-color: var(--gold-border);
    box-shadow: 0 10px 30px rgba(251, 191, 36, 0.15);
    background: var(--bg-card-hover);
}

.adv-icon {
    width: 60px;
    height: 60px;
    background: rgba(251, 191, 36, 0.12);
    border: 1px solid var(--gold-border);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: var(--primary-yellow);
    margin-bottom: 20px;
}

.adv-card h3 {
    font-size: 1.4rem;
    margin-bottom: 12px;
}

.adv-card p {
    color: var(--text-secondary);
    font-size: 1.05rem;
    line-height: 1.6;
}

/* Pricing Section (套餐价格) - Exact Match with Screenshot Layout */
.pricing {
    padding: 80px 0;
    background: rgba(18, 23, 34, 0.6);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
    align-items: stretch;
    max-width: 1140px;
    margin: 0 auto;
}

/* Pricing Cards styled cleanly & prominently */
.pricing-card {
    background: #ffffff;
    color: var(--text-dark);
    border-radius: var(--radius-md);
    padding: 38px 30px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    border: 1px solid #e2e8f0;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    transition: var(--transition);
    position: relative;
}

.pricing-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
}

/* Popular Featured Card Styling (Center Card) */
.pricing-card.featured {
    border: 2.5px solid var(--brand-blue);
    box-shadow: 0 15px 35px rgba(37, 99, 235, 0.25);
    transform: scale(1.03);
}

.pricing-card.featured:hover {
    transform: scale(1.05) translateY(-5px);
}

.pricing-header {
    text-align: center;
    margin-bottom: 25px;
}

.pricing-title {
    font-size: 1.6rem;
    font-weight: 800;
    color: #1e293b;
    margin-bottom: 15px;
}

.pricing-price {
    font-size: 2.6rem;
    font-weight: 900;
    color: #0f172a;
    line-height: 1;
    margin-bottom: 15px;
}

.pricing-price span {
    font-size: 1.1rem;
    font-weight: 500;
    color: #64748b;
}

.pricing-subtitle {
    font-size: 0.95rem;
    color: #64748b;
    font-weight: 500;
    min-height: 22px;
}

.pricing-features {
    list-style: none;
    margin: 25px 0 35px 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.pricing-features li {
    font-size: 1.05rem;
    color: #334155;
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
}

.pricing-features li .check-icon {
    color: #10b981;
    font-weight: bold;
    font-size: 1.2rem;
}

/* Card Button Styling */
.btn-pricing {
    width: 100%;
    padding: 13px 0;
    border-radius: var(--radius-sm);
    font-size: 1.15rem;
    font-weight: 800;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    display: block;
}

.btn-pricing-outline {
    background: transparent;
    border: 1.5px solid var(--brand-blue);
    color: var(--brand-blue);
}

.btn-pricing-outline:hover {
    background: rgba(37, 99, 235, 0.08);
    color: var(--brand-blue);
}

.btn-pricing-solid {
    background: var(--brand-blue);
    border: 1.5px solid var(--brand-blue);
    color: #ffffff;
    box-shadow: 0 4px 15px rgba(37, 99, 235, 0.35);
}

.btn-pricing-solid:hover {
    background: var(--brand-blue-hover);
    border-color: var(--brand-blue-hover);
    color: #ffffff;
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.5);
}

/* Knowledge Base & Tutorials Section (知识库与教程板块) */
.kb-section {
    padding: 80px 0;
}

.kb-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 25px;
}

.kb-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: 28px;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.kb-card:hover {
    transform: translateY(-5px);
    border-color: var(--gold-border);
    background: var(--bg-card-hover);
    box-shadow: 0 10px 25px rgba(0,0,0,0.4);
}

.kb-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
    font-size: 0.88rem;
    color: var(--text-muted);
}

.kb-tag {
    padding: 3px 10px;
    background: rgba(251, 191, 36, 0.15);
    color: var(--primary-yellow);
    border-radius: 4px;
    font-weight: bold;
}

.kb-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
    line-height: 1.4;
    color: var(--text-primary);
}

.kb-card h3 a {
    color: var(--text-primary);
}

.kb-card h3 a:hover {
    color: var(--primary-yellow);
}

.kb-excerpt {
    color: var(--text-secondary);
    font-size: 0.98rem;
    margin-bottom: 20px;
    line-height: 1.6;
}

.kb-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 15px;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    font-size: 0.95rem;
    font-weight: bold;
}

.kb-link {
    color: var(--primary-yellow);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

/* User Reviews Section (用户评价) */
.reviews {
    padding: 80px 0;
    background: rgba(18, 23, 34, 0.4);
}

.reviews-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 25px;
}

.review-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: 28px;
    position: relative;
}

.review-user {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 16px;
}

.user-avatar {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--primary-yellow), var(--yellow-dark));
    color: var(--text-dark);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.2rem;
}

.user-info h4 {
    font-size: 1.1rem;
    margin-bottom: 2px;
}

.user-info p {
    font-size: 0.88rem;
    color: var(--text-muted);
}

.stars {
    color: var(--primary-yellow);
    margin-bottom: 12px;
    font-size: 1rem;
}

.review-content {
    color: var(--text-secondary);
    font-size: 1.02rem;
    line-height: 1.6;
}

/* FAQ Section (常见问题) */
.faq {
    padding: 80px 0;
}

.faq-list {
    max-width: 900px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.faq-item {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: var(--transition);
}

.faq-question {
    padding: 22px 28px;
    font-size: 1.2rem;
    font-weight: bold;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
}

.faq-question:hover {
    color: var(--primary-yellow);
}

.faq-toggle {
    font-size: 1.4rem;
    color: var(--primary-yellow);
    transition: transform 0.3s ease;
}

.faq-item.active .faq-toggle {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
    padding: 0 28px;
    color: var(--text-secondary);
    font-size: 1.05rem;
    line-height: 1.7;
}

.faq-item.active .faq-answer {
    max-height: 1000px;
    padding: 0 28px 24px 28px;
    transition: max-height 0.3s ease-in-out;
}

/* Footer & Keyword Cloud Section (60 search keywords + 60 cocoduck keywords = 120 total) */
.footer-keywords {
    padding: 70px 0 30px 0;
    background: #07090e;
    border-top: 1px solid rgba(251, 191, 36, 0.15);
}

.kw-block {
    margin-bottom: 40px;
}

.kw-title {
    font-size: 1.3rem;
    margin-bottom: 20px;
    color: var(--primary-yellow);
    border-left: 4px solid var(--primary-yellow);
    padding-left: 12px;
}

.kw-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.kw-tag {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: var(--text-secondary);
    padding: 5px 12px;
    border-radius: 4px;
    font-size: 0.88rem;
    transition: var(--transition);
}

.kw-tag:hover {
    background: rgba(251, 191, 36, 0.12);
    border-color: var(--gold-border);
    color: var(--primary-yellow);
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* Article Subpage Specific Styling */
.article-page {
    padding: 50px 0;
}

.article-container {
    max-width: 920px;
    margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-lg);
    padding: 45px;
    box-shadow: var(--shadow-card);
}

.article-header {
    margin-bottom: 35px;
    padding-bottom: 25px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.article-title {
    font-size: 2.3rem;
    line-height: 1.3;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.article-meta {
    display: flex;
    gap: 20px;
    color: var(--text-muted);
    font-size: 0.95rem;
    flex-wrap: wrap;
}

.article-body {
    font-size: 1.1rem;
    line-height: 1.85;
    color: var(--text-secondary);
}

.article-body h2 {
    font-size: 1.7rem;
    margin: 40px 0 20px 0;
    color: var(--primary-yellow);
    border-bottom: 1px solid rgba(251, 191, 36, 0.2);
    padding-bottom: 8px;
}

.article-body h3 {
    font-size: 1.35rem;
    margin: 28px 0 14px 0;
    color: var(--text-primary);
}

.article-body p {
    margin-bottom: 20px;
}

.article-body ul, .article-body ol {
    margin: 0 0 24px 24px;
}

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

.article-cta-box {
    margin: 45px 0;
    padding: 30px;
    background: linear-gradient(135deg, rgba(251, 191, 36, 0.12), rgba(245, 158, 11, 0.05));
    border: 1.5px solid var(--gold-border);
    border-radius: var(--radius-md);
    text-align: center;
}

.article-cta-box h3 {
    font-size: 1.6rem;
    margin-bottom: 12px;
    color: var(--primary-yellow);
}

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

.related-articles {
    margin-top: 50px;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 15px;
    margin-top: 15px;
}

.related-card {
    padding: 16px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255, 255, 255, 0.05);
}

/* Responsive Media Queries */
@media (max-width: 992px) {
    .hero-grid {
        grid-template-columns: 1fr;
    }
    .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 480px;
    }
    .pricing-card.featured {
        transform: scale(1);
    }
    .pricing-card.featured:hover {
        transform: translateY(-5px);
    }
    .hero-content h1 {
        font-size: 2.4rem;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: rgba(11, 14, 20, 0.98);
        flex-direction: column;
        padding: 20px;
        border-bottom: 1px solid var(--gold-border);
    }
    .nav-menu.show {
        display: flex;
    }
    .mobile-toggle {
        display: block;
    }
    .hero-content h1 {
        font-size: 2.1rem;
    }
    .article-container {
        padding: 25px;
    }
    .article-title {
        font-size: 1.8rem;
    }
}