body {
  font-family: sans-serif;
  margin: 0;
  padding: 0;
  background: #f4f4f4;
  color: #333;
}

header {
  background: #1f2937;
  color: white;
  padding: 1rem;
  text-align: center;
}

main {
  padding: 1rem;
}

.exercise-card {
  background: white;
  padding: 1rem;
  margin: 0.5rem 0;
  border-radius: 6px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

button {
  background: #10b981;
  border: none;
  color: white;
  padding: 0.5rem 1rem;
  margin-top: 0.5rem;
  cursor: pointer;
  border-radius: 4px;
  font-size: 1rem;
}

button:hover {
  background: #059669;
}

select, input {
  margin-top: 0.5rem;
  padding: 0.4rem;
  width: 100%;
  border-radius: 4px;
  border: 1px solid #ccc;
}