*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{--bg:#0a0a1a;--surface:#12122a;--surface2:#1a1a3a;--accent:#6c63ff;--accent2:#ff6584;--accent3:#43e97b;--text:#e8e8f0;--text2:#a0a0c0;--radius:12px;--shadow:0 4px 24px rgba(0,0,0,.4)}
html{scroll-behavior:smooth}
body{font-family:'Segoe UI',system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;overflow-x:hidden}
canvas#particles{position:fixed;top:0;left:0;width:100%;height:100%;z-index:0;pointer-events:none}
.wrap{position:relative;z-index:1}
a{color:var(--accent);text-decoration:none;transition:color .2s}
a:hover{color:var(--accent2)}
h1,h2,h3{font-weight:700}
.container{max-width:1200px;margin:0 auto;padding:0 20px}
/* NAV */
nav{position:fixed;top:0;left:0;right:0;z-index:100;background:rgba(10,10,26,.92);backdrop-filter:blur(12px);border-bottom:1px solid rgba(108,99,255,.15);padding:14px 0}
nav .container{display:flex;align-items:center;justify-content:space-between}
nav .logo{font-size:1.4rem;font-weight:800;background:linear-gradient(135deg,var(--accent),var(--accent2));-webkit-background-clip:text;-webkit-text-fill-color:transparent}
nav ul{display:flex;gap:24px;list-style:none}
nav ul a{color:var(--text2);font-size:.9rem;font-weight:500}
nav ul a:hover{color:var(--accent)}
.hamburger{display:none;flex-direction:column;gap:5px;cursor:pointer;background:none;border:none}
.hamburger span{display:block;width:24px;height:2px;background:var(--text)}
/* HERO */
.hero{min-height:100vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:120px 20px 80px}
.hero h1{font-size:clamp(2.2rem,6vw,4.5rem);margin-bottom:16px;background:linear-gradient(135deg,#6c63ff,#ff6584,#43e97b);-webkit-background-clip:text;-webkit-text-fill-color:transparent}
.hero p{font-size:1.2rem;color:var(--text2);max-width:600px;margin:0 auto 32px}
.btn{display:inline-block;padding:12px 28px;border-radius:50px;font-weight:600;font-size:.95rem;cursor:pointer;border:none;transition:all .3s}
.btn-primary{background:linear-gradient(135deg,var(--accent),var(--accent2));color:#fff}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 6px 20px rgba(108,99,255,.4)}
.btn-outline{border:2px solid var(--accent);color:var(--accent);background:transparent}
.btn-outline:hover{background:var(--accent);color:#fff}
.hero-btns{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}
/* SECTIONS */
section{padding:80px 0}
.section-title{text-align:center;margin-bottom:48px}
.section-title h2{font-size:2rem;margin-bottom:8px}
.section-title p{color:var(--text2)}
/* CARDS GRID */
.grid{display:grid;gap:24px}
.grid-2{grid-template-columns:repeat(auto-fit,minmax(320px,1fr))}
.grid-3{grid-template-columns:repeat(auto-fit,minmax(300px,1fr))}
.grid-5{grid-template-columns:repeat(auto-fit,minmax(220px,1fr))}
.card{background:var(--surface);border:1px solid rgba(108,99,255,.1);border-radius:var(--radius);padding:28px;transition:transform .3s,box-shadow .3s}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.card h3{margin-bottom:8px;font-size:1.1rem}
.card p{color:var(--text2);font-size:.9rem}
.card .icon{font-size:2rem;margin-bottom:12px;display:block}
.tag{display:inline-block;background:rgba(108,99,255,.15);color:var(--accent);padding:3px 10px;border-radius:50px;font-size:.75rem;margin:4px 4px 0 0}
/* PLAYGROUND TABS */
.playground{background:var(--surface);border-radius:var(--radius);border:1px solid rgba(108,99,255,.12);overflow:hidden}
.pg-tabs{display:flex;flex-wrap:wrap;background:var(--surface2);border-bottom:1px solid rgba(108,99,255,.1)}
.pg-tab{padding:12px 20px;cursor:pointer;font-size:.85rem;font-weight:600;color:var(--text2);border:none;background:none;transition:all .2s;white-space:nowrap}
.pg-tab.active{color:var(--accent);border-bottom:2px solid var(--accent);background:rgba(108,99,255,.05)}
.pg-panel{display:none;padding:32px;min-height:340px}
.pg-panel.active{display:block}
.pg-panel label{display:block;font-weight:600;margin-bottom:6px;font-size:.9rem}
.pg-panel select,.pg-panel input[type=text],.pg-panel textarea{width:100%;padding:10px 14px;border-radius:8px;border:1px solid rgba(108,99,255,.2);background:var(--surface2);color:var(--text);font-size:.9rem;margin-bottom:16px}
.pg-panel textarea{min-height:80px;resize:vertical}
.pg-panel .output{background:var(--bg);border:1px solid rgba(108,99,255,.15);border-radius:8px;padding:20px;margin-top:16px;min-height:60px;white-space:pre-wrap;font-size:.9rem;line-height:1.7}
.pg-panel .btn{margin-top:8px}
.slider-group{margin-bottom:16px}
.slider-group input[type=range]{width:100%;accent-color:var(--accent)}
.slider-group .val{font-size:.85rem;color:var(--accent);font-weight:700}
/* TABLE */
.compare-table{width:100%;border-collapse:collapse;font-size:.85rem}
.compare-table th,.compare-table td{padding:10px 12px;text-align:left;border-bottom:1px solid rgba(108,99,255,.1)}
.compare-table th{background:var(--surface2);color:var(--accent);font-weight:700;position:sticky;top:0}
.compare-table tr:hover td{background:rgba(108,99,255,.04)}
.table-wrap{overflow-x:auto;border-radius:8px;border:1px solid rgba(108,99,255,.12)}
/* CHARTS */
.chart-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:24px}
.chart-card{background:var(--surface);border:1px solid rgba(108,99,255,.1);border-radius:var(--radius);padding:20px}
.chart-card h3{font-size:.95rem;margin-bottom:12px;color:var(--text2)}
.chart-card canvas{width:100%;height:220px;display:block}
/* FOOTER */
footer{text-align:center;padding:40px 20px;color:var(--text2);font-size:.85rem;border-top:1px solid rgba(108,99,255,.1)}
/* COPY BTN */
.copy-btn{background:var(--accent);color:#fff;border:none;padding:6px 16px;border-radius:6px;cursor:pointer;font-size:.8rem;margin-top:8px}
.copy-btn:hover{opacity:.85}
/* LEARNING GUIDES STYLING */
.guide-card{transition:transform .3s,box-shadow .3s;opacity:0;transform:translateY(30px)}
.guide-card.visible{opacity:1;transform:translateY(0);transition:opacity .6s ease,transform .6s ease,box-shadow .3s}
.guide-card.visible:hover{transform:translateY(-4px)}
.guide-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.guide-expand{max-height:0!important;overflow:hidden!important;transition:max-height .5s cubic-bezier(.22,1,.36,1)!important}
.guide-card.expanded .guide-expand{max-height:5000px!important}
.guide-card.expanded .expand-hint{display:none!important}
.expand-hint{opacity:.7;cursor:pointer;display:block;transition:opacity .3s}
/* RESPONSIVE */
@media(max-width:768px){
nav ul{display:none;flex-direction:column;position:absolute;top:56px;left:0;right:0;background:rgba(10,10,26,.97);padding:20px;gap:16px}
nav ul.open{display:flex}
.hamburger{display:flex}
.pg-tabs{overflow-x:auto}
.pg-tab{padding:10px 14px;font-size:.8rem}
.pg-panel{padding:20px}
section{padding:50px 0}
}