/* math games - Purple/Indigo Theme */
:root{
  --bg:#1e1b4b;
  --bg2:#312e81;
  --card:#ffffff;
  --primary:#4f46e5;
  --primary-light:#818cf8;
  --accent:#fbbf24;
  --success:#34d399;
  --danger:#f87171;
  --text:#1e1b4b;
  --text-light:#6366f1;
  --muted:#64748b;
  --border:#e0e7ff;
  --radius:12px;
  --shadow:0 4px 24px rgba(79,70,229,0.12);
  --mg-theme:#4f46e5;
}
[data-mg-theme="dark"]{
  --bg:#1e1b4b;
  --bg2:#0f0c29;
  --card:#1e1b4b;
  --text:#f8fafc;
  --text-light:#c7d2fe;
  --muted:#94a3b8;
  --border:rgba(255,255,255,0.1);
  --shadow:0 4px 24px rgba(0,0,0,0.3);
}
*{margin:0;padding:0;box-sizing:border-box}
body{
  font-family:system-ui,-apple-system,'Segoe UI',Roboto,sans-serif;
  background:linear-gradient(135deg,var(--bg2),var(--bg));
  color:var(--text);
  min-height:100vh;
  line-height:1.6;
}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}

/* Nav */
.nav{
  display:flex;align-items:center;justify-content:space-between;
  padding:10px 20px;background:rgba(255,255,255,0.06);
  backdrop-filter:blur(8px);border-bottom:1px solid rgba(255,255,255,0.08);
  position:sticky;top:0;z-index:100;
}
[data-mg-theme="light"] .nav{background:rgba(255,255,255,0.9);border-bottom:1px solid var(--border)}
.nav-brand{font-size:18px;font-weight:700;color:var(--primary-light);display:flex;align-items:center;gap:8px}
[data-mg-theme="light"] .nav-brand{color:var(--primary)}
.nav-links{display:flex;gap:16px;align-items:center;flex-wrap:wrap}
.nav-links a{color:var(--text-light);font-size:14px;font-weight:500}
[data-mg-theme="light"] .nav-links a{color:var(--muted)}
.nav-links a:hover{color:var(--accent);text-decoration:none}
.lang-select{
  background:rgba(255,255,255,0.1);border:1px solid rgba(255,255,255,0.15);
  color:var(--text);padding:4px 8px;border-radius:6px;font-size:13px;cursor:pointer;
}
[data-mg-theme="light"] .lang-select{background:#fff;border-color:var(--border);color:var(--text)}

/* Container */
.container{max-width:960px;margin:0 auto;padding:20px}

/* Hero */
.hero{text-align:center;padding:32px 16px 20px}
.hero h1{font-size:32px;font-weight:800;color:#fff;margin-bottom:8px}
[data-mg-theme="light"] .hero h1{color:var(--text)}
.hero p{font-size:15px;color:var(--text-light);max-width:560px;margin:0 auto}
[data-mg-theme="light"] .hero p{color:var(--muted)}

/* Game */
.game-wrap{
  display:flex;justify-content:center;align-items:center;
  background:rgba(255,255,255,0.04);border-radius:var(--radius);padding:16px;margin:16px 0;
  box-shadow:var(--shadow);
}
[data-mg-theme="light"] .game-wrap{background:#fff;border:1px solid var(--border)}
#game-canvas{
  max-width:100%;border-radius:8px;
  background:#1e1b4b;cursor:pointer;touch-action:manipulation;
  box-shadow:0 0 40px rgba(79,70,229,0.15);
}

/* Diff buttons */
.diff-row{display:flex;gap:10px;justify-content:center;margin:12px 0}
.diff-btn{
  padding:8px 20px;border-radius:8px;border:2px solid var(--border);
  background:transparent;color:var(--text);font-weight:600;font-size:14px;
  cursor:pointer;transition:all 0.2s;
}
.diff-btn.active{background:var(--primary);border-color:var(--primary);color:#fff}

/* Highlights */
.highlights{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px;margin:24px 0}
.highlight{
  background:rgba(255,255,255,0.05);border:1px solid rgba(255,255,255,0.08);
  border-radius:var(--radius);padding:16px;transition:transform 0.2s;
}
[data-mg-theme="light"] .highlight{background:#f8fafc;border-color:var(--border)}
.highlight:hover{transform:translateY(-2px)}
.highlight h3{font-size:15px;color:var(--primary-light);margin-bottom:4px}
[data-mg-theme="light"] .highlight h3{color:var(--primary)}
.highlight p{font-size:13px;color:var(--muted)}

/* FAQ */
.faq{margin:24px 0}
.faq-item{
  background:rgba(255,255,255,0.04);border:1px solid rgba(255,255,255,0.08);
  border-radius:var(--radius);padding:14px 16px;margin-bottom:8px;
}
[data-mg-theme="light"] .faq-item{background:#f8fafc;border-color:var(--border)}
.faq-q{font-weight:600;color:var(--text);font-size:14px;margin-bottom:4px}
.faq-a{font-size:13px;color:var(--muted);line-height:1.5}

/* About section */
.about{background:rgba(255,255,255,0.04);border-radius:var(--radius);padding:20px;margin:24px 0}
[data-mg-theme="light"] .about{background:#f8fafc;border:1px solid var(--border)}
.about p{color:var(--text-light);font-size:14px}
[data-mg-theme="light"] .about p{color:var(--muted)}

/* Footer */
.footer{
  text-align:center;padding:20px;margin-top:32px;
  border-top:1px solid rgba(255,255,255,0.08);font-size:13px;color:var(--muted);
}
[data-mg-theme="light"] .footer{border-top-color:var(--border)}
.footer a{margin:0 8px}

/* How to play */
.howto{
  background:rgba(255,255,255,0.04);border-radius:var(--radius);padding:20px;margin:24px 0;
}
[data-mg-theme="light"] .howto{background:#f8fafc;border:1px solid var(--border)}
.howto h2{font-size:18px;color:#fff;margin-bottom:12px}
[data-mg-theme="light"] .howto h2{color:var(--text)}
.howto ol{padding-left:20px}
.howto li{font-size:14px;color:var(--text-light);margin-bottom:6px}
[data-mg-theme="light"] .howto li{color:var(--muted)}

/* Theme toggle */
.theme-toggle{
  background:rgba(255,255,255,0.1);border:1px solid rgba(255,255,255,0.15);
  color:var(--text);padding:4px 12px;border-radius:6px;font-size:13px;cursor:pointer;
}
[data-mg-theme="light"] .theme-toggle{background:#fff;border-color:var(--border)}

/* Responsive */
@media(max-width:640px){
  .nav{flex-direction:column;gap:8px}
  .hero h1{font-size:24px}
  #game-canvas{width:100%}
  .highlights{grid-template-columns:1fr}
}