/* Reset dan dasar */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Segoe UI', Tahoma, sans-serif;
  background-color: #e0f7fa;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}
.form-container {
  background: #ffffff;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  width: 100%;
  max-width: 400px;
}
.form-container h2 {
  margin-bottom: 1.5rem;
  color: #00796b;
  text-align: center;
}
.form-group {
  margin-bottom: 1rem;
}
.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
}
.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.6rem;
  border: 1px solid #b2dfdb;
  border-radius: 4px;
}
.form-group textarea {
  resize: vertical;
}
#username-status {
  font-size: 0.9rem;
  margin-top: 0.3rem;
}
#username-status.available {
  color: green;
}
#username-status.unavailable {
  color: red;
}
.btn-submit {
  width: 100%;
  padding: 0.75rem;
  border: none;
  background: #00796b;
  color: #ffffff;
  font-size: 1rem;
  border-radius: 4px;
  cursor: pointer;
}
.btn-submit:disabled {
  background: #80cbc4;
  cursor: not-allowed;
}
.btn-submit:hover:not(:disabled) {
  background: #005f56;
}