:root {
  --bg: #0f172a;
  --card: #111827;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --accent-2: #22c55e;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Inter, system-ui, sans-serif;

  background: radial-gradient(circle at top, rgba(56, 189, 248, 0.16), transparent 35%),
  linear-gradient(180deg, #020617 0%, #0b1120 100%);

  color: var(--text);
}

.container {
  max-width: 860px;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

.hero {
  text-align: center;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  margin: 0;
  letter-spacing: -0.06em;
}

.subtitle {
  margin: 14px auto 0;
  color: var(--accent);
  font-size: 1.15rem;
}

.card {
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);

  border: 1px solid rgba(255,255,255,0.18);
  border-radius: 24px;
  padding: 26px;

  box-shadow: 0 8px 32px rgba(0,0,0,0.35);
}


.hidden {
  display: none;
}

h2,
h3 {
  margin: 0 0 18px;
}

form label,
.answer-label {
  display: block;
  margin-bottom: 18px;
  font-size: 0.98rem;
  color: var(--muted);
}

input,
textarea {
  width: 100%;
  margin-top: 8px;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid rgba(148, 163, 184, 0.18);
  background: #111827;
  color: var(--text);
  font: inherit;
}

textarea {
  resize: vertical;
}

button {
  cursor: pointer;
  border: none;
  border-radius: 14px;
  font: inherit;
  padding: 14px 20px;
}

button.primary {
  background: linear-gradient(135deg, var(--accent), #22d3ee);
  color: #0f172a;
}

button.secondary {
  background: rgba(56, 189, 248, 0.16);
  color: var(--accent);
  border: 1px solid rgba(56, 189, 248, 0.38);
}

button:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.question-box {
  background: #0b1225;
  border-radius: 18px;
  padding: 18px;
  margin-bottom: 22px;
}

pre {
  margin: 0;
  white-space: pre-wrap;
  word-break: break-word;
  color: #c7d2fe;
}

.timer-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  font-weight: 600;
}