app.css

@charset 'UTF-8';

html {
  font-family: sans-serif;
  touch-action: manipulation;
}
.container {
  padding: 15px;
  max-width: 400px;
  margin: 0 auto;
  text-align: center;
  font-size: 16px;
}
.title {
  font-size: 20px;
  margin: 10px 0 20px;
}
.btn-tap {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  color: #fff;
  background-color: #a0ce00;
  border: none;
  outline: none;
  font-size: 20px;
  margin-bottom: 30px;
  cursor: pointer;
}
.btn-tap:disabled {
  background-color: #ddd;
  color: #aaa;
}
.btn-tap span {
  font-size: 60px;
}
.btn {
  display: inline-block;
  width: min(100%, 240px);
  margin: 30px 0 0;
  padding: 15px;
  border: none;
  border-radius: 10px;
  background-color: #54bbc1;
  font-size: 18px;
  color: #fff;
  font-weight: bold;
  cursor: pointer;
}
.btn-tw {
  background-color: #46a1eb;
  display: none;
}
.btn + .btn {
  margin-top: 20px;
}
.time span {
  display: inline-block;
  width: 50px;
  font-size: 20px;
  font-weight: bold;
}