@import "https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&family=Manrope:wght@200;300;400;500;600;700;800&display=swap";:root{--bg:#0e0e0e;--surface:#1a1a1a;--surface-2:#242424;--primary:#c799ff;--primary-low:#c799ff1a;--primary-mid:#c799ff66;--tx:#fff;--tx-dim:#a0a0a0;--tx-low:#606060;--accent:#c799ff;--success:#0fc;--error:#ff5f5f;--br-lg:24px;--br-md:16px;--br-p:12px;--shadow-sm:0 4px 12px #00000080;--shadow-md:0 8px 24px #0009;--glass:#ffffff08;--glass-border:#ffffff0d}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent;outline:none}body{background:var(--bg);color:var(--tx);-webkit-font-smoothing:antialiased;margin:0;font-family:Manrope,sans-serif;font-size:15px;line-height:1.6;overflow-x:hidden}h1,h2,h3,.syne,.font-heading{letter-spacing:-.02em;font-family:Space Grotesk,sans-serif;font-weight:600}.mono{font-variant-numeric:tabular-nums;font-family:Space Grotesk,monospace}.app{max-width:480px;min-height:100vh;margin:0 auto;padding:24px 20px 100px;position:relative}.bento-grid{grid-template-columns:repeat(2,1fr);gap:12px;margin-bottom:24px;display:grid}.bento-item{background:var(--surface);border-radius:var(--br-lg);border:1px solid #0000;padding:24px;transition:transform .3s cubic-bezier(.34,1.56,.64,1),background .3s;position:relative;overflow:hidden}.bento-item:hover{background:var(--surface-2);border-color:var(--glass-border);transform:translateY(-4px)}.bento-span-2{grid-column:span 2}.card{background:var(--surface);border-radius:var(--br-lg);box-shadow:var(--shadow-sm);padding:20px;transition:all .3s;position:relative}.card:hover{box-shadow:var(--shadow-md);transform:translateY(-2px)}.card-glass{background:var(--glass);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border:1px solid var(--glass-border)}.tag{text-transform:uppercase;letter-spacing:.8px;background:var(--primary-low);color:var(--primary);border-radius:20px;padding:4px 10px;font-size:10px;font-weight:700;display:inline-flex}.btn-primary{background:var(--primary);color:#0e0e0e;border-radius:var(--br-md);cursor:pointer;border:none;justify-content:center;align-items:center;gap:8px;width:100%;padding:14px 24px;font-family:Space Grotesk,sans-serif;font-weight:700;transition:all .2s cubic-bezier(.4,0,.2,1);display:flex}.btn-primary:active{transform:scale(.96)}.topic{background:var(--surface);border-radius:var(--br-md);cursor:pointer;border:1px solid #0000;align-items:center;gap:12px;margin-bottom:12px;padding:20px;font-size:14px;transition:all .2s;display:flex}.topic:hover{background:var(--surface-2);border-color:var(--glass-border);transform:translate(4px)}.cbtn{background:var(--surface);border-radius:var(--br-md);width:100%;color:var(--tx);text-align:left;cursor:pointer;border:1px solid #0000;margin-bottom:10px;padding:18px 20px;font-family:Manrope,sans-serif;font-size:14px;font-weight:500;transition:all .2s}.cbtn:hover{background:var(--surface-2)}.cbtn.ok{color:var(--success);background:#00ffcc1a;border-color:#00ffcc4d}.cbtn.ng{color:var(--error);background:#ff5f5f1a;border-color:#ff5f5f4d}.fc{perspective:1000px;cursor:pointer;width:100%}.fci{width:100%;transform-style:preserve-3d;transition:transform .6s cubic-bezier(.4,0,.2,1);position:relative}.fci.flip{transform:rotateY(180deg)}.fcf{backface-visibility:hidden;border-radius:var(--br-lg);text-align:center;width:100%;height:100%;box-shadow:var(--shadow-md);justify-content:center;align-items:center;padding:32px;display:flex;position:absolute}.fcfront{background:var(--surface);color:var(--tx);border:1px solid var(--glass-border)}.fcback{background:var(--primary);color:#0e0e0e;transform:rotateY(180deg)}.bnav{-webkit-backdrop-filter:blur(24px);backdrop-filter:blur(24px);border-top:1px solid var(--glass-border);z-index:100;background:#0e0e0ed9;justify-content:space-around;width:100%;max-width:480px;padding:16px 12px 32px;display:flex;position:fixed;bottom:0;left:50%;transform:translate(-50%)}.nb{color:var(--tx-low);text-transform:uppercase;letter-spacing:.5px;cursor:pointer;background:0 0;border:none;flex-direction:column;align-items:center;gap:6px;font-size:10px;font-weight:700;transition:all .3s;display:flex}.nb.a{color:var(--primary)}.nb.a span:first-child{filter:drop-shadow(0 0 12px var(--primary));transform:scale(1.1)}.pbar{background:#ffffff0d;border-radius:12px;height:8px;margin:12px 0;overflow:hidden}.pfill{background:linear-gradient(90deg, var(--primary), #fff);border-radius:12px;height:100%;transition:width 1s cubic-bezier(.22,1,.36,1)}@keyframes pulse{0%{opacity:1;transform:scale(1)}50%{opacity:.7;transform:scale(1.02)}to{opacity:1;transform:scale(1)}}.pulse{animation:3s ease-in-out infinite pulse}.hud-card{text-align:center;background:var(--glass);border:1px solid var(--glass-border);border-radius:var(--br-md);padding:16px 8px}.backbtn{background:var(--surface);border:1px solid var(--glass-border);color:var(--tx-dim);border-radius:var(--br-p);cursor:pointer;padding:10px 18px;font-family:Space Grotesk,sans-serif;font-size:13px;font-weight:700;transition:all .2s}.backbtn:hover{background:var(--surface-2);color:var(--tx)}.tab{background:var(--surface);border-radius:var(--br-md);border:1px solid var(--glass-border);gap:6px;margin-bottom:24px;padding:6px;display:flex}.tbtn{color:var(--tx-dim);text-transform:uppercase;letter-spacing:.5px;cursor:pointer;background:0 0;border:none;border-radius:12px;flex:1;padding:12px;font-size:12px;font-weight:800;transition:all .3s cubic-bezier(.4,0,.2,1)}.tbtn.a{background:var(--surface-2);color:var(--tx);box-shadow:var(--shadow-sm)}.ki{background:var(--surface);border-radius:var(--br-lg);border:1px solid #0000;gap:16px;margin-bottom:12px;padding:20px;transition:all .2s;display:flex}.ki:hover{border-color:var(--glass-border);background:var(--surface-2)}.smb{background:var(--surface);border:1px solid var(--glass-border);color:var(--tx-dim);border-radius:var(--br-md);cursor:pointer;padding:12px 20px;font-family:Space Grotesk,sans-serif;font-size:12px;font-weight:700;transition:all .2s}.smb:hover{background:var(--surface-2);color:var(--tx)}.explanation-content{color:#ffffffe6;font-size:16px;line-height:1.8}.explanation-content h2{color:var(--primary);border-bottom:1px solid var(--glass-border);margin:32px 0 16px;padding-bottom:8px;font-size:22px}.explanation-content h3{color:#fff;align-items:center;gap:8px;margin:24px 0 12px;font-size:18px;display:flex}.explanation-content h3:before{content:"";background:var(--primary);border-radius:2px;width:4px;height:18px;display:inline-block}.explanation-content h4{color:var(--primary);text-transform:uppercase;letter-spacing:.5px;margin:20px 0 10px;font-size:16px;font-weight:700}.explanation-content strong{color:#fff;background:#c799ff26;border-radius:4px;padding:0 4px;font-weight:800}.explanation-content .term{color:var(--success);border-bottom:1.5px dashed #0fc6;font-weight:700}.explanation-content p{margin-bottom:16px}.explanation-content ul{margin-bottom:20px;padding-left:20px}.explanation-content li{margin-bottom:8px;list-style-type:none;position:relative}.explanation-content li:before{content:"•";color:var(--primary);font-weight:800;position:absolute;left:-15px}.explanation-content .math,.explanation-content .math-var{color:var(--primary);letter-spacing:.5px;background:#c799ff0d;border-radius:6px;padding:2px 6px;font-family:Space Grotesk,serif;font-style:italic;font-weight:600}.explanation-content .important-box{-webkit-backdrop-filter:blur(16px);border:1px solid #ffffff1a;border-left:5px solid var(--primary);background:linear-gradient(135deg,#c799ff1f,#00ffcc14);border-radius:4px 20px 20px 4px;margin:32px 0;padding:24px 28px;position:relative;box-shadow:0 15px 35px -5px #0006,inset 0 0 20px #c799ff0d}.explanation-content .important-box:before{content:"💡";background:var(--surface-2);box-shadow:var(--shadow-sm);border-radius:50%;padding:4px;font-size:20px;position:absolute;top:-15px;left:10px}