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

:root{
    --color-bg:#f0f2f5;
    --color-surface:#ffffff;
    --color-primary:#0f1b2d;
    --color-primary-light:#1a2a42;
    --color-accent:#00d4ff;
    --color-accent-dim:rgba(0,212,255,0.12);
    --color-violet:#7c5cfc;
    --color-violet-dim:rgba(124,92,252,0.10);
    --color-text:#2c3e50;
    --color-text-light:#5a6b7f;
    --color-text-muted:#8899aa;
    --color-border:#e2e8f0;
    --color-border-light:#f1f5f9;
    --radius:12px;
    --radius-sm:8px;
    --radius-lg:16px;
    --shadow:0 1px 3px rgba(15,27,45,0.06),0 1px 2px rgba(15,27,45,0.04);
    --shadow-md:0 4px 12px rgba(15,27,45,0.08),0 2px 4px rgba(15,27,45,0.04);
    --shadow-lg:0 10px 30px rgba(15,27,45,0.10);
    --font-stack:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
    --font-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,monospace;
    --max-width:1200px;
    --header-h:64px;
}

html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{font-family:var(--font-stack);font-size:16px;line-height:1.7;color:var(--color-text);background:var(--color-bg);-webkit-font-smoothing:antialiased;min-height:100vh}

.skip-link{position:absolute;top:-100%;left:16px;background:var(--color-accent);color:var(--color-primary);padding:8px 16px;border-radius:var(--radius-sm);font-weight:600;z-index:999;text-decoration:none}
.skip-link:focus{top:8px}

.container{width:100%;max-width:var(--max-width);margin:0 auto;padding:0 24px}

a{color:var(--color-accent);text-decoration:none;transition:color .2s}
a:hover{color:var(--color-violet)}

img{max-width:100%;height:auto;display:block}

h1,h2,h3,h4,h5,h6{color:var(--color-primary);line-height:1.3;font-weight:700}
h1{font-size:clamp(1.75rem,4vw,2.5rem);letter-spacing:-0.02em}
h2{font-size:clamp(1.35rem,3vw,1.75rem);letter-spacing:-0.01em}
h3{font-size:clamp(1.1rem,2.5vw,1.35rem)}

/* Header */
.site-header{background:var(--color-primary);position:sticky;top:0;z-index:100;height:var(--header-h);border-bottom:1px solid rgba(255,255,255,0.06)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:var(--header-h)}
.logo{display:flex;align-items:center;gap:10px;text-decoration:none;color:#fff;font-weight:700;font-size:1.1rem}
.logo-text{letter-spacing:-0.01em}
.logo svg{flex-shrink:0}

.menu-toggle{display:none;background:none;border:none;color:#fff;cursor:pointer;padding:4px;border-radius:var(--radius-sm)}

.main-nav .nav-list{display:flex;list-style:none;gap:4px}
.main-nav a{color:rgba(255,255,255,0.7);padding:8px 14px;border-radius:var(--radius-sm);font-size:.875rem;font-weight:500;transition:all .2s;text-decoration:none;display:block;white-space:nowrap}
.main-nav a:hover,.main-nav a[aria-current="page"]{color:#fff;background:rgba(255,255,255,0.08)}
.main-nav a[aria-current="page"]{color:var(--color-accent)}

/* Hero */
.hero{background:linear-gradient(135deg,var(--color-primary) 0%,var(--color-primary-light) 50%,#1e3352 100%);padding:80px 0 60px;color:#fff;position:relative;overflow:hidden}
.hero::before{content:'';position:absolute;top:-50%;right:-20%;width:60%;height:200%;background:radial-gradient(circle,rgba(0,212,255,0.06) 0%,transparent 70%);pointer-events:none}
.hero::after{content:'';position:absolute;bottom:-50%;left:-10%;width:50%;height:200%;background:radial-gradient(circle,rgba(124,92,252,0.05) 0%,transparent 70%);pointer-events:none}
.hero-content{position:relative;z-index:1;max-width:800px}
.hero h1{color:#fff;margin-bottom:20px}
.hero p{color:rgba(255,255,255,0.75);font-size:1.125rem;line-height:1.8;max-width:640px}
.hero-badge{display:inline-flex;align-items:center;gap:6px;background:rgba(0,212,255,0.12);color:var(--color-accent);padding:6px 14px;border-radius:20px;font-size:.8rem;font-weight:600;margin-bottom:20px;letter-spacing:0.03em;text-transform:uppercase}

/* Page Header */
.page-header{background:linear-gradient(135deg,var(--color-primary) 0%,var(--color-primary-light) 100%);padding:48px 0 40px;color:#fff}
.page-header h1{color:#fff;margin-bottom:10px}
.page-header p{color:rgba(255,255,255,0.7);font-size:1rem}

/* Breadcrumbs */
.breadcrumbs{padding:16px 0;font-size:.85rem}
.breadcrumbs ol{display:flex;flex-wrap:wrap;list-style:none;gap:4px;align-items:center}
.breadcrumbs li::after{content:'›';margin-left:6px;color:var(--color-text-muted)}
.breadcrumbs li:last-child::after{display:none}
.breadcrumbs a{color:var(--color-text-light)}
.breadcrumbs span{color:var(--color-text-muted)}

/* Sections */
.section{padding:60px 0}
.section--alt{background:var(--color-surface)}
.section-header{text-align:center;margin-bottom:48px;max-width:640px;margin-left:auto;margin-right:auto}
.section-header p{color:var(--color-text-light);margin-top:12px;font-size:1.05rem}
.section-label{display:inline-block;color:var(--color-accent);font-size:.8rem;font-weight:700;letter-spacing:0.08em;text-transform:uppercase;margin-bottom:10px}

/* Cards Grid */
.card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:24px}
.card-grid--3{grid-template-columns:repeat(auto-fill,minmax(300px,1fr))}
.card-grid--2{grid-template-columns:repeat(auto-fill,minmax(400px,1fr))}

/* Cards */
.card{background:var(--color-surface);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow);border:1px solid var(--color-border);transition:box-shadow .25s,transform .25s}
.card:hover{box-shadow:var(--shadow-md);transform:translateY(-2px)}
.card-icon{width:48px;height:48px;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center;margin-bottom:16px;flex-shrink:0}
.card-icon--cyan{background:var(--color-accent-dim);color:var(--color-accent)}
.card-icon--violet{background:var(--color-violet-dim);color:var(--color-violet)}
.card-icon svg{width:24px;height:24px}
.card h3{margin-bottom:10px;font-size:1.1rem}
.card p{color:var(--color-text-light);font-size:.925rem;line-height:1.65}
.card-link{display:inline-flex;align-items:center;gap:4px;color:var(--color-accent);font-size:.875rem;font-weight:600;margin-top:14px}
.card-link:hover{gap:8px}

/* Insight Cards */
.insight-card{background:var(--color-surface);border-radius:var(--radius);padding:24px;border:1px solid var(--color-border);display:flex;gap:16px;align-items:flex-start}
.insight-card .insight-number{font-size:2rem;font-weight:800;color:var(--color-accent);line-height:1;flex-shrink:0;min-width:48px}
.insight-card h3{font-size:1rem;margin-bottom:6px}
.insight-card p{color:var(--color-text-light);font-size:.875rem}

/* Stats Block */
.stats-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:20px}
.stat-block{background:var(--color-surface);border-radius:var(--radius);padding:24px;text-align:center;border:1px solid var(--color-border)}
.stat-value{font-size:2rem;font-weight:800;color:var(--color-primary);letter-spacing:-0.02em}
.stat-value--accent{color:var(--color-accent)}
.stat-value--violet{color:var(--color-violet)}
.stat-label{font-size:.85rem;color:var(--color-text-light);margin-top:4px}

/* Article Tile */
.article-tile{background:var(--color-surface);border-radius:var(--radius);padding:24px 28px;border:1px solid var(--color-border);transition:box-shadow .25s;display:block;text-decoration:none;color:inherit}
.article-tile:hover{box-shadow:var(--shadow-md);color:inherit}
.article-tile .tile-meta{display:flex;gap:12px;align-items:center;font-size:.8rem;color:var(--color-text-muted);margin-bottom:10px}
.article-tile h3{color:var(--color-primary);margin-bottom:8px;font-size:1.05rem}
.article-tile p{color:var(--color-text-light);font-size:.9rem;line-height:1.6}

/* Comparison Table */
.table-wrap{overflow-x:auto;-webkit-overflow-scrolling:touch;border-radius:var(--radius);border:1px solid var(--color-border)}
.comparison-table{width:100%;border-collapse:collapse;font-size:.9rem}
.comparison-table th{background:var(--color-primary);color:#fff;padding:14px 18px;text-align:left;font-weight:600;white-space:nowrap}
.comparison-table td{padding:12px 18px;border-bottom:1px solid var(--color-border-light)}
.comparison-table tr:last-child td{border-bottom:none}
.comparison-table tr:nth-child(even){background:var(--color-border-light)}

/* Article Content */
.article-content{max-width:760px}
.article-content h2{margin:36px 0 16px;padding-top:12px}
.article-content h3{margin:28px 0 12px}
.article-content p{margin-bottom:18px;color:var(--color-text);line-height:1.8}
.article-content ul,.article-content ol{margin:0 0 18px 24px;color:var(--color-text)}
.article-content li{margin-bottom:8px;line-height:1.7}
.article-content blockquote{border-left:3px solid var(--color-accent);padding:16px 20px;background:var(--color-accent-dim);border-radius:0 var(--radius-sm) var(--radius-sm) 0;margin:24px 0;font-style:italic;color:var(--color-text-light)}

.article-meta{display:flex;flex-wrap:wrap;gap:16px;align-items:center;padding:16px 0;margin-bottom:24px;border-bottom:1px solid var(--color-border);font-size:.875rem;color:var(--color-text-muted)}
.article-meta a{color:var(--color-accent);font-weight:500}

/* Sidebar */
.content-layout{display:grid;grid-template-columns:1fr 300px;gap:48px;align-items:start}
.sidebar{position:sticky;top:calc(var(--header-h) + 24px)}
.sidebar-card{background:var(--color-surface);border-radius:var(--radius);padding:24px;border:1px solid var(--color-border);margin-bottom:20px}
.sidebar-card h3{font-size:.95rem;margin-bottom:14px;padding-bottom:10px;border-bottom:1px solid var(--color-border)}
.sidebar-card ul{list-style:none}
.sidebar-card li{margin-bottom:8px}
.sidebar-card a{color:var(--color-text-light);font-size:.875rem;display:block;padding:4px 0}
.sidebar-card a:hover{color:var(--color-accent)}

/* FAQ */
.faq-list{max-width:760px;margin:0 auto}
.faq-item{background:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius);margin-bottom:12px;overflow:hidden}
.faq-question{width:100%;display:flex;justify-content:space-between;align-items:center;padding:18px 24px;background:none;border:none;cursor:pointer;font-size:1rem;font-weight:600;color:var(--color-primary);text-align:left;font-family:var(--font-stack);gap:12px}
.faq-question:hover{color:var(--color-accent)}
.faq-question svg{flex-shrink:0;transition:transform .25s;width:20px;height:20px;color:var(--color-text-muted)}
.faq-item.active .faq-question svg{transform:rotate(180deg)}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .3s ease;padding:0 24px}
.faq-answer-inner{padding:0 0 18px;color:var(--color-text-light);font-size:.925rem;line-height:1.7}

/* Author Card */
.author-card{display:flex;gap:20px;padding:24px;background:var(--color-surface);border-radius:var(--radius);border:1px solid var(--color-border)}
.author-avatar{width:72px;height:72px;border-radius:50%;background:linear-gradient(135deg,var(--color-accent-dim),var(--color-violet-dim));display:flex;align-items:center;justify-content:center;flex-shrink:0;font-size:1.5rem;font-weight:700;color:var(--color-primary)}
.author-info h3{margin-bottom:2px;font-size:1.1rem}
.author-info .author-role{color:var(--color-accent);font-size:.85rem;font-weight:500;margin-bottom:8px;display:block}
.author-info p{color:var(--color-text-light);font-size:.9rem;line-height:1.65}
.author-tags{display:flex;flex-wrap:wrap;gap:6px;margin-top:12px}
.author-tag{background:var(--color-accent-dim);color:var(--color-accent);font-size:.75rem;font-weight:600;padding:4px 10px;border-radius:20px}

/* Glossary */
.glossary-group{margin-bottom:36px}
.glossary-letter{font-size:1.5rem;font-weight:800;color:var(--color-accent);margin-bottom:16px;padding-bottom:8px;border-bottom:2px solid var(--color-accent-dim)}
.glossary-item{padding:12px 0;border-bottom:1px solid var(--color-border-light)}
.glossary-item:last-child{border-bottom:none}
.glossary-term{font-weight:700;color:var(--color-primary);font-size:1rem}
.glossary-def{color:var(--color-text-light);font-size:.9rem;margin-top:4px;line-height:1.6}

/* Contact Form */
.contact-form{max-width:560px}
.form-group{margin-bottom:20px}
.form-group label{display:block;font-size:.875rem;font-weight:600;color:var(--color-primary);margin-bottom:6px}
.form-group input,.form-group textarea,.form-group select{width:100%;padding:12px 16px;border:1px solid var(--color-border);border-radius:var(--radius-sm);font-size:.95rem;font-family:var(--font-stack);color:var(--color-text);background:var(--color-surface);transition:border-color .2s}
.form-group input:focus,.form-group textarea:focus,.form-group select:focus{outline:none;border-color:var(--color-accent);box-shadow:0 0 0 3px var(--color-accent-dim)}
.form-group textarea{min-height:140px;resize:vertical}
.btn{display:inline-flex;align-items:center;gap:8px;padding:12px 28px;border-radius:var(--radius-sm);font-size:.95rem;font-weight:600;font-family:var(--font-stack);border:none;cursor:pointer;transition:all .2s}
.btn--primary{background:var(--color-accent);color:var(--color-primary)}
.btn--primary:hover{background:#00bfe6;transform:translateY(-1px)}
.form-status{margin-top:16px;padding:12px 16px;border-radius:var(--radius-sm);font-size:.9rem;display:none}
.form-status--success{display:block;background:#e8faf0;color:#1a7a4c;border:1px solid #b8e8cc}
.form-status--error{display:block;background:#fef2f2;color:#b91c1c;border:1px solid #fecaca}

/* Knowledge Box */
.knowledge-box{background:linear-gradient(135deg,var(--color-primary) 0%,var(--color-primary-light) 100%);border-radius:var(--radius-lg);padding:40px;color:#fff;margin:40px 0}
.knowledge-box h2{color:#fff;margin-bottom:16px}
.knowledge-box p{color:rgba(255,255,255,0.8);line-height:1.7}
.knowledge-box .highlight-stat{font-size:2.5rem;font-weight:800;color:var(--color-accent);display:block;margin:12px 0}

/* Responsible Play Banner */
.rp-banner{background:linear-gradient(135deg,#1a0a3e 0%,var(--color-primary) 100%);border-radius:var(--radius-lg);padding:40px;color:#fff;text-align:center;margin:40px 0}
.rp-banner .age-badge--large{display:inline-flex;align-items:center;justify-content:center;width:56px;height:56px;border-radius:50%;background:rgba(255,255,255,0.1);border:2px solid var(--color-accent);font-size:1.25rem;font-weight:800;color:var(--color-accent);margin-bottom:16px}
.rp-banner h2{color:#fff;margin-bottom:12px}
.rp-banner p{color:rgba(255,255,255,0.7);max-width:540px;margin:0 auto;font-size:.95rem}

/* Age Badge (footer) */
.age-badge{display:inline-flex;align-items:center;justify-content:center;width:36px;height:36px;border-radius:50%;border:2px solid var(--color-accent);font-size:.8rem;font-weight:800;color:var(--color-accent);flex-shrink:0}

/* Icon Blocks */
.icon-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:20px}
.icon-block{display:flex;gap:14px;align-items:flex-start;padding:20px;background:var(--color-surface);border-radius:var(--radius);border:1px solid var(--color-border)}
.icon-block svg{width:24px;height:24px;flex-shrink:0;color:var(--color-accent);margin-top:2px}
.icon-block h4{font-size:.95rem;margin-bottom:4px}
.icon-block p{color:var(--color-text-light);font-size:.85rem;line-height:1.55}

/* Error page */
.error-page{text-align:center;padding:100px 0}
.error-code{font-size:6rem;font-weight:800;color:var(--color-accent);line-height:1;letter-spacing:-0.04em}
.error-page h1{margin:16px 0 12px}
.error-page p{color:var(--color-text-light);margin-bottom:28px}

/* Footer */
.site-footer{background:var(--color-primary);color:rgba(255,255,255,0.6);padding:60px 0 0;margin-top:60px}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;gap:40px;padding-bottom:40px;border-bottom:1px solid rgba(255,255,255,0.08)}
.footer-logo{display:flex;align-items:center;gap:10px;color:#fff;font-weight:700;font-size:1.05rem;margin-bottom:12px}
.footer-desc{font-size:.875rem;line-height:1.65;color:rgba(255,255,255,0.5)}
.footer-col h3{color:#fff;font-size:.85rem;font-weight:700;text-transform:uppercase;letter-spacing:0.05em;margin-bottom:16px}
.footer-col ul{list-style:none}
.footer-col li{margin-bottom:8px}
.footer-col a{color:rgba(255,255,255,0.55);font-size:.875rem;text-decoration:none;transition:color .2s}
.footer-col a:hover{color:var(--color-accent)}
.footer-notice{display:flex;align-items:center;gap:16px;padding:24px 0;border-bottom:1px solid rgba(255,255,255,0.08)}
.footer-notice p{font-size:.8rem;color:rgba(255,255,255,0.4);line-height:1.6}
.footer-bottom{padding:20px 0;text-align:center;font-size:.8rem;color:rgba(255,255,255,0.35)}

/* Legal page */
.legal-content{max-width:760px}
.legal-content h2{margin:32px 0 14px}
.legal-content h3{margin:24px 0 10px}
.legal-content p{margin-bottom:14px;line-height:1.75;color:var(--color-text-light)}
.legal-content ul{margin:0 0 16px 24px}
.legal-content li{margin-bottom:6px;color:var(--color-text-light);line-height:1.65}
.legal-content .last-updated{color:var(--color-text-muted);font-size:.85rem;margin-bottom:24px}

/* Mobile responsive */
@media(max-width:1024px){
    .content-layout{grid-template-columns:1fr}
    .sidebar{position:static;order:2}
    .footer-grid{grid-template-columns:1fr 1fr}
}

@media(max-width:768px){
    .container{padding:0 16px}
    .section{padding:40px 0}
    .hero{padding:48px 0 40px}

    .menu-toggle{display:block}
    .main-nav{display:none;position:absolute;top:var(--header-h);left:0;right:0;background:var(--color-primary);border-top:1px solid rgba(255,255,255,0.06);padding:16px;box-shadow:var(--shadow-lg)}
    .main-nav.active{display:block}
    .main-nav .nav-list{flex-direction:column;gap:2px}
    .main-nav a{padding:12px 16px}

    .card-grid,.card-grid--3,.card-grid--2{grid-template-columns:1fr}
    .stats-grid{grid-template-columns:repeat(2,1fr)}
    .icon-grid{grid-template-columns:1fr}
    .footer-grid{grid-template-columns:1fr;gap:32px}
    .footer-notice{flex-direction:column;text-align:center}
    .author-card{flex-direction:column;align-items:center;text-align:center}
    .author-tags{justify-content:center}
}

@media(max-width:480px){
    .stats-grid{grid-template-columns:1fr}
    .hero h1{font-size:1.5rem}
}