ui.css

/* CSS */
.btn {
  background-color: rgba(51, 51, 51, 0.05);
  border-radius: 8px;
  border: 1px solid rgba(51, 51, 51, 0.05);
  color: #333333;
  cursor: pointer;
  display: inline-block;
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  margin: 0;
  padding: 10px 12px;
  text-align: center;
  white-space: nowrap;
}

.btn.primary {
  background-color: rgba(51, 51, 51, 0.9);
  border-color: #000000;
  color: white;
}

.btn:active {
  border: 1px solid black;
}

.input {
  background-color: rgba(51, 51, 51, 0.05);
  border-radius: 8px;
  border: 1px solid rgba(51, 51, 51, 0.05);
  color: #333333;
  display: inline-block;
  font-size: 14px;
  font-weight: 500;
  line-height: 20px;
  margin: 0;
  padding: 10px 12px;
  white-space: nowrap;
}

.input[disabled] {
  background-color: rgba(51, 51, 51, 0.2);
}

.btn[disabled] {
  background-color: rgba(51, 51, 51, 0.2);
}

.to-high {
  background: #ff7979;
}

.to-low {
  background: #18dcff;
}

.correct {
  background: #32ff7e;
}