html, body {
  height: 100%;
  width: 100%;
  overflow: hidden;
  margin: 0;
}

.grass, .sky, .road {
  position: relative;
  width: 100%;
}

.sky {
  height: 40vh;
  background: skyblue;
}

.grass {
  height: 30vh;
  background: seagreen;
  display: flex;
  position: relative;
}

.tree1, .tree2, .tree3 {
  position: absolute;
  width: 10vw;
  height: auto;
}

.tree1 {
  top: 0;
  right: 10%;
}

.tree2 {
  top: 0;
  left: 30%; 
}

.road {
  height: 30vh;
  background: dimgrey;
  box-sizing: border-box;
  border-top: 1vh solid grey;
  border-bottom: 1vh solid grey;
}

.lines {
  box-sizing: border-box;
  border: 0.5vh dashed #fff;
  height: 0;
  width: 100%;
  position: absolute;
  top: 50%;
}

.mario {
  position: absolute;
  top: -5vh;
  left: 0;
  width: 8vw;
  animation: drive 3s both infinite linear, jump 0.3s 1.2s ease;
}

.luigi {
  position: absolute;
  top: 15vh;
  left: 0;
  width: 8vw;
  animation: drive 5s both infinite linear;
}

.toad {
  position: absolute;
  top: 7vh;
  left: 0;
  width: 8vw;
  animation: drive 7s both infinite linear, jump 0.3s 1.2s ease;
}

.peel {
  position: absolute;
  left: 30%;
  width: 5vw;
}

.cloud {
  position: absolute;
}

.cloud:nth-child(1) {
  width: 15vw;
  top: 12vh;
  opacity: 0.5;
  animation: wind 80s linear infinite reverse;
}

.cloud:nth-child(2) {
  width: 20vw;
  top: 0;
  animation: wind 50s linear infinite reverse;
}

@keyframes drive {
  from {
    transform: translateX(-20vw);
  }
  to {
    transform: translateX(100vw);
  }
}

@keyframes wind {
  from {
    left: -30vw;
  }
  to {
    left: 100vw;
  }
}

@keyframes jump {
  0% {
    top: -5vh;
  } 
  50% {
    top: -10vh;
  }
  100% {
    top: -5vh;
  }
}