.fish-tank {
  border: 20px solid #006AB1;
  width: 100%;
  height: 100%;
  box-sizing: border-box;
  display: flex;
  flex-grow: 1;
}

.fish-tank-content {
  display: flex;
  background: white;
  border-radius: 20px;
  padding: 40px;
  width: 100%;
  color: #006AB1;
  font-size: 80px;
  text-align: center;
  justify-content: center;
  align-items: center;
  flex-direction: column;
  gap: 30px;
  background-color: #a2dff760;
  position: relative;
  overflow: hidden;
}

.start-button {
  width: 300px;
  height: auto;
  padding: 15px 0;
  border: 2px solid black;
  border-radius: 50px;
  font-size: 40px;
  font-family: 'Chewy';
  background-color: #6A449B;
  color: white;
}

.index-text {
  animation-name: fadeIn;
  animation-duration: 1s;
  opacity: 0;
  animation-fill-mode: forwards;
  overflow: hidden;
}

.algae {
  position: absolute;
  left: 10px;
  bottom: -20px;
  height: 230px;
  width: auto;
}

.bubble {
  position: absolute;
  opacity: 0;
  animation-fill-mode: forwards;
}

.bubble1 {
  width: 30px;
  bottom: 150px;
  right: 70px;
  animation-name: riseUp;
  animation-duration: 3s;
  animation-delay: .5s;
}

.bubble2 {
  width: 45px;
  bottom: 100px;
  right: 30px;
  animation-name: riseUp;
  animation-duration: 4s;
}

.bubble3 {
  width: 35px;
  bottom: 90px;
  right: 85px;
  animation-name: riseUp;
  animation-duration: 4s;
  animation-delay: .3s;
}

.bubble4 {
  width: 30px;
  bottom: 55px;
  right: 50px;
  animation-name: riseUp;
  animation-duration: 2s;
  animation-delay: .2s;
}

.bubble5 {
  width: 27px;
  bottom: 30px;
  right: 80px;
  animation-name: riseUp;
  animation-duration: 2s;
}