html,body {height: 100%;margin: 0;}
body {font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;cursor: pointer;}
.container {display: flex;justify-content: center;align-items: center;height: 100%;}
#score {position: absolute;top: 30px;right: 30px;font-size: 2em;font-weight: 900;}
#introduction {width: 200px;height: 150px;position: absolute;font-weight: 600;font-size: 0.8em;font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;text-align: center;transition: opacity 2s;}
#restart {width: 120px;height: 120px;position: absolute;border-radius: 50%;color: white;background-color: red;border: none;font-weight: 700;font-size: 1.2em;font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;display: none;cursor: pointe;
}
#perfect {position: absolute;opacity: 0;transition: opacity 2s;}
#youtube {display: none;}
@media (min-height: 425px) {
  #youtube {z-index: 2;display: block;width: 100px;height: 70px;position: absolute;bottom: 20px;left: 20px;background: red;border-radius: 50% / 11%;transform: scale(0.8);transition: transform 0.5s;}
  #youtube:hover,
  #youtube:focus {transform: scale(0.9);}
  #youtube::before {content: "";display: block;position: absolute;top: 7.5%;left: -6%;width: 112%;height: 85%;background: red;border-radius: 9% / 50%;}
  #youtube::after {content: "";display: block;position: absolute;top: 20px;left: 40px;width: 45px;height: 30px;border: 15px solid transparent;box-sizing: border-box;border-left: 30px solid white;}
  #youtube span {font-size: 0;position: absolute;width: 0;height: 0;overflow: hidden;}
}