body{margin:0;padding:0;overflow:hidden;}
:root {
  --green: #32CD32;
  --blue: #4D4DFF;
}

/* Background */

.background {
  background: #fff url(../img/beij.png) repeat right bottom;
  position: absolute;
  top: 0;
  left: -100vw;
  width: 200vw;
  height: 350px;
  z-index: -1;
  -moz-animation: background 30s infinite linear;
  -webkit-animation: background 30s infinite linear;
}
@keyframes background {
  0% {
    margin-left: 0;
  }
  100% {
    margin-left: 100vw;
  }
}
.road {
  background-color: #666684;
  position: absolute;
  top: 350px;
  left: 0;
  height: 240px;
  width: 100vw;
  z-index: -1;
}
/* Bikes */

.bikes {
  display: flex;
  justify-content: space-between;
  width: 1000px;
  margin: 110px auto 0px;
  padding-bottom: 50px;
}

/* Small bike */

.bike-small {
  position: relative;
  width: 400px;
  display: block;
  padding-top: 100px;
}
.bike-small .frame .front,
.bike-small .frame .main .top,
.bike-small .frame .main .bottom,
.bike-small .frame .back {
  background-color: var(--green)
}
.bike-small .frame {
  display: flex;
  justify-content: center;
  width: 56%;
  margin: auto;
  height: 100px;
  z-index: 1;
  position: relative;
}
.bike-small .frame .front {
  width: 8px;
  height: 100%;
  transform: rotate(25deg);
  margin: -2px 0px 0px -40px;
  position: relative;
}
.bike-small .frame .front:after {
  content: '';
  width: 14px;
  height: 14px;
  background-color: #000;
  position: absolute;
  bottom: 0;
  border-radius: 100%;
  margin: 0px 0px -7px -2.5px;
}
.bike-small .frame .front .handles {
  background-color: #222;
  width: 30px;
  height: 6px;
  transform: rotate(-25deg);
  position: absolute;
  top: 0;
  margin: -7px 0px 0px -3px;
  border-radius: 5px;
}
.bike-small .frame .main {
  width: 50%;
}
.bike-small .frame .main .top {
  height: 6px;
  width: 100%;
  margin: 13px 0px 0px 12px;
}
.bike-small .frame .main .bottom {
  height: 6px;
  width: 92%;
  transform: rotate(40deg);
  margin: 33px 0px 0px -5px;
}
.bike-small .frame .main .pedals {
  width: 55px;
  height: 4px;
  background-color: #222;
  margin: 28px 0px 0px auto;
  position: relative;
  z-index: 3;
  display: flex;
  justify-content: center;
  align-items: center;
  -moz-animation: pedalsSpin 1.5s infinite linear;
  -webkit-animation: pedalsSpin 1.5s infinite linear;
}
@keyframes pedalsSpin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(-180deg);
  }
}
.bike-small .frame .main .pedals .pedal {
  width: 30px;
  height: 30px;
  background-color: #000;
  border-radius: 100%;
}
.bike-small .frame .back {
  width: 6px;
  height: 100%;
  transform: rotate(25deg);
  margin: 0px 0px 0px -8px;
  position: relative;
}
.bike-small .frame .back .top {
  width: 4px;
  height: 85%;
  margin: -7px 0px 0px 38px;
  background-color: #222;
  transform: rotate(-55deg);
  position: relative;
  z-index: 5;
}
.bike-small .frame .back .top:after {
  content: '';
  width: 14px;
  height: 14px;
  background-color: #000;
  position: absolute;
  bottom: 0;
  border-radius: 100%;
  margin: 0px 0px -12px -5px;
}
.bike-small .frame .back .bottom {
  width: 4px;
  height: 100%;
  background-color: #222;
  position: absolute;
  transform: rotate(68deg);
  top: 0;
  margin: 30px 0px 0px 37px;
}
.bike-small .frame .back .seat {
  background-color: #222;
  width: 35px;
  height: 12px;
  border-radius: 10px;
  position: absolute;
  top: 0;
  transform: rotate(-25deg);
  margin: -5px 0px 0px -20px;
}
.bike-small .tires {
  width: 78%;
  display: flex;
  justify-content: space-between;
  margin: -70px auto 0px;
  z-index: -1;
  position: relative;
}
.bike-small .tire {
  border: 10px solid #222;
  height: 102px;
  width: 102px;
  border-radius: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  -moz-animation: tireSpin 1s infinite linear;
  -webkit-animation: tireSpin 1s infinite linear;
  position: relative;
  z-index: -1;
}
@keyframes tireSpin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(-180deg);
  }
}
.bike-small .tire .tire-inner {
  height: 105px;
  width: 105px;
  border-radius: 100%;
  position: relative;
  z-index: -1;
}
.bike-small .tire .tire-inner .spoke {
  background-color: #222;
  width: 100%;
  height: 2px;
  position: absolute;
  top: 50%;
}
.bike-small .tire .tire-inner .spoke:nth-child(2) {
  transform: rotate(90deg);
}
.bike-small .tire .tire-inner .spoke:nth-child(3) {
  transform: rotate(135deg);
}
.bike-small .tire .tire-inner .spoke:nth-child(4) {
  transform: rotate(45deg);
}

/* Large Bike */

.bike-large {
  position: relative;
  width: 600px;
  display: block;
  padding-top: 50px
}
.bike-large .frame .front,
.bike-large .frame .main .top,
.bike-large .frame .main .bottom,
.bike-large .frame .back {
  background-color: var(--blue)
}
.bike-large .frame {
  display: flex;
  justify-content: center;
  width: 71%;
  margin: auto;
  height: 150px;
  z-index: 1;
  position: relative;
  margin-top: -17px;
}
.bike-large .frame .front {
  width: 10px;
  height: 100%;
  transform: rotate(25deg);
  margin: 0px 0px 0px -40px;
  position: relative;
}
.bike-large .frame .front:after {
  content: '';
  width: 16px;
  height: 16px;
  background-color: #000;
  position: absolute;
  bottom: 0;
  border-radius: 100%;
  margin: 0px 0px -7px -3px;
}
.bike-large .frame .front .handles {
  background-color: #222;
  width: 50px;
  height: 8px;
  transform: rotate(-25deg);
  position: absolute;
  top: 0;
  margin: -12px 0px 0px -5px;
  border-radius: 5px;
}
.bike-large .frame .main {
  width: 50%;
}
.bike-large .frame .main .top {
  height: 8px;
  width: 100%;
  margin: 15px 0px 0px 18px;
}
.bike-large .frame .main .bottom {
  height: 8px;
  width: 88%;
  transform: rotate(35deg);
  margin: 62px 0px 0px -6px;
}
.bike-large .frame .main .pedals {
  width: 70px;
  height: 6px;
  background-color: #222;
  margin: 40px 15px 0px auto;
  position: relative;
  z-index: 3;
  display: flex;
  justify-content: center;
  align-items: center;
  -moz-animation: pedalsSpin 2s infinite linear;
  -webkit-animation: pedalsSpin 2s infinite linear;
}
@keyframes pedalsSpin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(-180deg);
  }
}
.bike-large .frame .main .pedals .pedal {
  width: 40px;
  height: 40px;
  background-color: #000;
  border-radius: 100%;
}
.bike-large .frame .back {
  width: 8px;
  height: 100%;
  transform: rotate(25deg);
  margin: 0px 0px 0px -12px;
  position: relative;
}
.bike-large .frame .back .top {
  width: 6px;
  height: 85%;
  margin: -5px 0px 0px 48px;
  background-color: #222;
  transform: rotate(-45deg);
  position: relative;
  z-index: 5;
}
.bike-large .frame .back .top:after {
  content: '';
  width: 16px;
  height: 16px;
  background-color: #000;
  position: absolute;
  bottom: 0;
  border-radius: 100%;
  margin: 0px 0px -12px -5px;
}
.bike-large .frame .back .bottom {
  width: 6px;
  height: 90%;
  background-color: #222;
  position: absolute;
  transform: rotate(67deg);
  top: 0;
  margin: 67px 0px 0px 37px;
}
.bike-large .frame .back .seat {
  background-color: #222;
  width: 45px;
  height: 16px;
  border-radius: 10px;
  position: absolute;
  top: 0;
  transform: rotate(-25deg);
  margin: -8px 0px 0px -28px;
}
.bike-large .tires {
  width: 78%;
  display: flex;
  justify-content: space-between;
  margin: -85px auto 0px;
  z-index: -1;
  position: relative;
}
.bike-large .tire {
  border: 12px solid #222;
  height: 130px;
  width: 130px;
  border-radius: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
  -moz-animation: tireSpin 1.5s infinite linear;
  -webkit-animation: tireSpin 1.5s infinite linear;
  position: relative;
  z-index: -1;
}
@keyframes tireSpin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(-180deg);
  }
}
.bike-large .tire .tire-inner {
  height: 135px;
  width: 135px;
  border-radius: 100%;
  position: relative;
  z-index: -1;
}
.bike-large .tire .tire-inner .spoke {
  background-color: #222;
  width: 100%;
  height: 2px;
  position: absolute;
  top: 50%;
}
.bike-large .tire .tire-inner .spoke:nth-child(2) {
  transform: rotate(90deg);
}
.bike-large .tire .tire-inner .spoke:nth-child(3) {
  transform: rotate(135deg);
}
.bike-large .tire .tire-inner .spoke:nth-child(4) {
  transform: rotate(45deg);
}
.bike-large .dirt {
  
}
.bike-large .dirt .spec {
  
}