.input-container {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  max-width: 300px;
  margin: 0 auto;
}
label {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
  color: #374151;
}
input {
  width: 100%;
  padding: 12px;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  font-size: 1rem;
  outline: none;
  box-sizing: border-box;
  transition: border-color 0.2s;
}
input:focus {
  border-color: #3b82f6;
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

const phoneInput = document.getElementById("phoneInput");

phoneInput.addEventListener("input", function(e) {
  let x = e.target.value.replace(/\D/g, "").match(/(\d{0,3})(\d{0,3})(\d{0,4})/);
  e.target.value = !x[2] ? x[1] : "(" + x[1] + ") " + x[2] + (x[3] ? "-" + x[3] : "");
});