Body {
  font-family: Calibri, Helvetica, sans-serif;
  background-color: pink;
}

button {
  background-color: #4CAF50;
  width: 100%;
  color: orange;
  padding: 15px;
  margin: 10px 0px;
  border: none;
  cursor: pointer;
}
button:disabled {
  background-color: grey;
  opacity: 0.45;
  cursor: not-allowed;
}

form {
  border: 3px solid #f1f1f1;
}

input[type=text] {
  width: 100%;
  margin: 8px 0;
  padding: 12px 20px;
  display: inline-block;
  border: 2px solid green;
  box-sizing: border-box;
}

button:hover {
  opacity: 0.7;
}


.container {
  padding: 25px;
  background-color: lightblue;
}

.error {
  display: block;
  color: red;
  margin: 5px 0 0 0;
}
#selector {
  text-align: center;
}