* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", system-ui, sans-serif;
  background: linear-gradient(160deg, #f0f9ff 0%, #e0f2fe 50%, #fef3c7 100%);
  color: #0f172a;
}

.hero {
  text-align: center;
  padding: 3rem 1.5rem 1rem;
}

.badge {
  display: inline-block;
  font-size: 0.75rem;
  background: #dbeafe;
  color: #1d4ed8;
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
}

.hero h1 {
  font-size: 2.5rem;
  margin: 0.75rem 0 0.25rem;
}

.subtitle {
  color: #475569;
  margin: 0;
}

.card {
  max-width: 420px;
  margin: 2rem auto;
  padding: 2rem;
  background: #fff;
  border-radius: 1rem;
  box-shadow: 0 10px 40px rgba(15, 23, 42, 0.08);
  text-align: center;
}

.mode {
  font-size: 0.875rem;
  color: #64748b;
  margin: 0 0 0.5rem;
}

.timer {
  font-size: 4rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: #0369a1;
  margin-bottom: 1.5rem;
}

.actions {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

button {
  border: none;
  border-radius: 0.5rem;
  padding: 0.6rem 1.2rem;
  font-size: 0.95rem;
  cursor: pointer;
}

#startBtn {
  background: #0284c7;
  color: #fff;
}

#pauseBtn,
#resetBtn {
  background: #f1f5f9;
  color: #334155;
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.stats {
  margin-top: 1.5rem;
  color: #64748b;
  font-size: 0.9rem;
}

footer {
  text-align: center;
  padding: 2rem;
  font-size: 0.8rem;
  color: #94a3b8;
}