/* Infinite Quiz — shared design tokens, reset, and primitives. */
:root {
  --bg: #0a0b12;
  --bg-2: #0d0f1c;
  --surface: rgba(255, 255, 255, 0.04);
  --surface-2: rgba(255, 255, 255, 0.07);
  --border: rgba(255, 255, 255, 0.10);
  --border-strong: rgba(255, 255, 255, 0.18);

  --text: #eceefb;
  --muted: #9aa0bf;
  --faint: #6b7193;

  --indigo: #6366f1;
  --violet: #8b5cf6;
  --cyan: #22d3ee;
  --pink: #ec4899;

  --good: #22c55e;
  --good-bg: rgba(34, 197, 94, 0.16);
  --bad: #ef4444;
  --bad-bg: rgba(239, 68, 68, 0.16);

  --grad: linear-gradient(120deg, var(--indigo), var(--violet) 45%, var(--cyan));
  --grad-warm: linear-gradient(120deg, var(--violet), var(--pink));

  --radius: 16px;
  --radius-lg: 22px;
  --shadow: 0 18px 50px -18px rgba(0, 0, 0, 0.7);
  --ring: 0 0 0 3px rgba(99, 102, 241, 0.45);

  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

html, body { height: 100%; }

body {
  font-family: var(--font);
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 80% -10%, rgba(139, 92, 246, 0.22), transparent 60%),
    radial-gradient(1000px 500px at 0% 110%, rgba(34, 211, 238, 0.16), transparent 55%),
    linear-gradient(180deg, var(--bg), var(--bg-2));
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  line-height: 1.5;
}

a { color: inherit; text-decoration: none; }

.brand {
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* Buttons -------------------------------------------------------------- */
.btn {
  --btn-bg: var(--surface-2);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  font: inherit;
  font-weight: 650;
  color: var(--text);
  background: var(--btn-bg);
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  padding: 0.85rem 1.5rem;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.2s ease, background 0.2s ease, border-color 0.2s ease;
  user-select: none;
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }
.btn:focus-visible { outline: none; box-shadow: var(--ring); }

.btn-primary {
  border: none;
  color: #0a0b12;
  background: var(--grad);
  font-weight: 750;
  box-shadow: 0 12px 30px -10px rgba(99, 102, 241, 0.7);
}
.btn-primary:hover { box-shadow: 0 18px 40px -10px rgba(99, 102, 241, 0.85); }

.btn-ghost { background: transparent; border-color: var(--border); color: var(--muted); }
.btn-ghost:hover { color: var(--text); border-color: var(--border-strong); }

.btn-sm { padding: 0.5rem 1rem; font-size: 0.9rem; }

.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.35rem 0.8rem;
}

.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}