html {
  box-sizing: border-box;
  font-size: 10px;
  background: #ffc600;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

body {
  padding: 0;
  margin: 0;
  font-family: cursive;
}

h1 {
  text-align: center;
  font-size: 10rem;
  line-height: 1;
  margin-bottom: 0;
}

.start{
    padding: 1.5rem;
    background: transparent;
    border: 2px solid rgba(0, 0, 0, 0.5);
    font-size: 2rem;
    width: 10rem;
    margin: 10px auto;
    display: block;
}

.start:hover{
    background-color: rgb(0, 0, 0);
    color: #ffc600;
}

.score {
  background: rgba(255, 255, 255, 0.2);
  padding: 0 3rem;
  line-height: 1;
  border-radius: 1rem;
}

.game {
  width: 600px;
  height: 400px;
  display: flex;
  flex-wrap: wrap;
  margin: 0 auto;
}

.hole {
  flex: 1 0 33.33%;
  overflow: hidden;
  position: relative;
}

.hole:after {
  display: block;
  background: url(dirt.svg) bottom center no-repeat;
  background-size: contain;
  content: "";
  width: 100%;
  height: 70px;
  position: absolute;
  z-index: 2;
  bottom: -30px;
}

.mole {
  background: url("mole.svg") bottom center no-repeat;
  background-size: 60%;
  position: absolute;
  top: 100%;
  width: 100%;
  height: 100%;
  transition: all 0.4s;
}

.hole.up .mole {
  top: 0;
}
