html,
body {
    background-color: #000000;
    height: 100%;
}
.button-icon {
    color:red;
    font-size: 50px;
    margin-left: 10px;
}
.row {
  height: 100%;
  padding: 0;
}
.full-height {
  height: 100%;
}
.floor {
  position: relative;
  height: 56%;
  border-bottom: solid 3px red;
}
.floor-bottom {
  height: 44%;
}
.left-box {
  position: relative;
  height: 100%;
  border-right: solid 2px red;
}
.right-box {
  position: relative;
  height: 100%;
  border-left: solid 2px red;
}
.left-service {
  position: absolute;
  height: 37.5%;
  width: 50%;
  top: 0;
  left: 0;
  border-right: solid 2px red;
  border-bottom: solid 2px red;
}
.right-service {
  position: absolute;
  height: 37.5%;
  width: 50%;
  top: 0;
  right: 0;
  border-left: solid 2px red;
  border-bottom: solid 2px red;
}
.court {
  /*background-image: url(../img/floor.jpg);*/
  background-color: #ffffff;
  border: solid 3px gray;
  position: relative;
}
.t-mark {
  position: absolute;
  left: 30%;
  width: 40%;
}
.top-20 {
  top: 20%;
}
.top-30 {
  top: 30%;
}
.bottom-5 {
  bottom: 5%;
}
.bottom-10 {
  bottom: 10%;
}
.bottom-15 {
  bottom: 15%;
}
.bottom-20 {
  bottom: 20%;
}
.bottom-30 {
  bottom: 30%;
}
.position-hidden {
  display: none;
}
.position-0 {
  top: 5px;
  left: 5px;
}
.position-1 {
  top: 5px;
  right: 5px;
}
.position-2 {
  top: 50%;
  left: 5px;
}
.position-3 {
  top: 50%;
  right: 5px;
}
.position-4 {
  bottom: 5px;
  left: 5px;
}
.position-5 {
  bottom: 5px;
  right: 5px;
}
#ball-mark {
  background-color: red;
  border-radius: 50%;
  box-shadow: 0 0 5px black;
  height: 100px;
  position: absolute;
  width: 100px;
}
#count-down {
    background-color: white;
    border: 2px solid red;
    border-radius: 50%;
    height: 180px;
    width: 180px;
}
#racket {
  height: 225px;
}
#start-button {
    background-color: #ffffff;
    border: solid 2px red;
    border-radius: 50px;
    height: 100px;
    width: 100px;
}
#time-counter {
    color: red;
    font-size: 80px;
    font-weight: bold;
    margin-top: 25px;
}
@media screen and (max-width: 600px) {
    .button-icon {
        font-size: 50px;
        margin-bottom: 10px;
    }
    #count-down {
        background-color: white;
        border-radius: 50%;
        height: 130px;
        width: 130px;
}
    #racket {
        height: 100px;
    }
    #start-button {
        bottom: 20px;
        border-radius: 40px;
        height: 80px;
        width: 80px;
    }
    #time-counter {
        color: red;
        font-size: 60px;
        font-weight: bold;
        margin-top: -10px;
    }
}