<button class="btn">Click me</button>

.btn {
  padding: 10px 18px;
  border: 0;
  border-radius: 8px;
  background: #4f46e5;
  color: white;
  font-weight: 600;
  cursor: pointer;
}
.btn:hover { background: #4338ca; }

document.querySelector('.btn')?.addEventListener('click', () => {
  console.log('Hello from your component!');
});