/* ------------------------------------------
 * IT书包
 * 网址：www.itshubao.com
 * 整理：yinq<3331653644@qq.com> 
 -------------------------------------------- */
html, body {
  height: 100%;
}

body {
  background: linear-gradient(to right, #56ccf2, #2f80ed);
}

.toy-train {
  position: relative;
  left: 50%;
  top: 50%;
  margin-left: -100px;
  width: 109px;
  transform: scale(1.2);
}

.engine {
  float: right;
  position: relative;
}

.window {
  height: 28px;
  width: 30px;
  background-color: #194488;
  position: relative;
  border: 3px solid #000;
}
.window:before, .window:after {
  content: "";
  position: absolute;
  left: 50%;
  border: 3px solid #000;
}
.window:before {
  height: 7px;
  background-color: #F82510;
  width: 45px;
  margin-top: -13px;
  margin-left: -26px;
  border-radius: 8px;
}
.window:after {
  margin-left: -8px;
  margin-top: 3px;
  border-radius: 50%;
  height: 11px;
  width: 11px;
  background-color: #fff;
}

.engine-main {
  height: 10px;
  width: 35px;
  border: 3px solid #000;
  background-color: #3D9A01;
  position: absolute;
  border-radius: 0 8px 8px 0;
  right: -41px;
  bottom: -3px;
}
.engine-main:before {
  content: "";
  height: 10px;
  width: 8px;
  background-color: #000;
  position: absolute;
  top: -11px;
  left: 4px;
  transform: rotate(180deg);
  border-radius: 50% 50% 50% 50% / 90% 90% 40% 40%;
}
.engine-main:after {
  content: "";
  height: 12px;
  width: 8px;
  position: absolute;
  display: block;
  right: 5px;
  top: -18px;
  border-radius: 50% 50% 50% 50% / 90% 90% 40% 40%;
  transform: rotate(180deg);
  z-index: -1;
  background-color: #194488;
  border: 3px solid #000;
}

.engine-body {
  height: 17px;
  width: 75px;
  position: absolute;
  left: -2px;
  top: 30px;
  background-color: #F69F00;
  border: 3px solid #000;
  border-radius: 5px;
}
.engine-body .big-wheel {
  top: 3px;
  left: 2px;
}
.engine-body .normal-wheel {
  left: 45px;
  top: 5px;
}
.engine-body:before {
  content: "";
  position: absolute;
  height: 5px;
  width: 5px;
  left: -11px;
  bottom: 2px;
  z-index: -1;
  background-color: #fff;
  border-radius: 50%;
  border: 3px solid #000;
}

.wheels > div {
  position: absolute;
  background-color: #F82510;
  border-radius: 50%;
  border: 3px solid #000;
  animation: wheel-rotate 1s linear infinite;
}
.wheels > div:before {
  content: "";
  position: absolute;
  width: 100%;
  border-bottom: 1px solid #000;
  top: 50%;
  margin-top: -1px;
}
.wheels > div:after {
  content: "";
  height: 8px;
  width: 8px;
  position: absolute;
  background-color: #000;
  border-radius: 50%;
  left: 50%;
  top: 50%;
  margin-left: -4px;
  margin-top: -4px;
}
.wheels .big-wheel {
  width: 22px;
  height: 22px;
  animation-delay: -0.3s;
}
.wheels .normal-wheel {
  height: 20px;
  width: 20px;
  animation-delay: -0.6s;
}

.locomotive {
  height: 35px;
  width: 60px;
  border: 3px solid #000;
  background-color: #F69F00;
  border-radius: 5px;
  position: relative;
  float: left;
  margin-top: 13px;
}
.locomotive:before {
  content: "";
  width: 100%;
  background: linear-gradient(to right, #000000 0%, #000000 8%, #f69f00 8%, #f69f00 15%, #000000 15%, #000000 28%, #000000 34%, #f69f00 34%, #f69f00 65%, #000000 65%, #000000 65%, #000000 100%);
  height: 3px;
  position: absolute;
  top: 6px;
  left: 0;
}
.locomotive:after {
  content: "";
  width: 100%;
  background: linear-gradient(to right, #000000 0%, #000000 24%, #f69f00 24%, #f69f00 65%, #f69f00 65%, #000000 65%, #000000 85%, #f69f00 85%, #f69f00 90%, #000000 90%, #000000 100%);
  height: 3px;
  position: absolute;
  top: 14px;
  left: 0;
}
.locomotive .wheels > div {
  top: 22px;
  animation-delay: -0.6s;
}
.locomotive .wheels > div:first-child {
  animation-delay: -0.9s;
}
.locomotive .normal-wheel:first-of-type {
  left: 2px;
}
.locomotive .normal-wheel:last-of-type {
  right: 2px;
}
.locomotive .trash {
  height: 35px;
  width: 50px;
  position: absolute;
  top: -18px;
  border: 3px solid #000;
  background-color: #3D9A01;
  border-radius: 50%;
  left: 2px;
  z-index: -1;
}

.tracks {
  position: relative;
  width: 200px;
  bottom: -10px;
  overflow: hidden;
  height: 3px;
}
.tracks span {
  display: inline-block;
  height: 3px;
  width: 200px;
  position: absolute;
  left: 200px;
  background: linear-gradient(to right, black 0%, black 30%, transparent 30%, transparent 39%, black 39%, black 61%, black 65%, transparent 65%, transparent 70%, black 71%, black 100%);
  animation: track 2s linear infinite;
  animation-fill-mode: forwards;
}
.tracks span:nth-child(2) {
  animation-delay: -1s;
}

.smokes:before, .smokes:after,
.smokes span:before {
  display: block;
  content: "";
  height: 8px;
  width: 8px;
  background-color: #fff;
  border-radius: 50%;
  position: absolute;
  right: 8px;
  top: 15px;
  z-index: -1;
}
.smokes:before {
  animation: smoke 1s linear infinite;
}
.smokes span:before {
  animation: smoke 1s linear infinite;
  animation-delay: -0.6s;
}
.smokes:after {
  animation: smoke 1s linear infinite;
  animation-delay: -0.3s;
}

@keyframes smoke {
  100% {
    top: -50px;
    opacity: 0.5;
  }
}
@keyframes wheel-rotate {
  100% {
    transform: rotate(360deg);
  }
}
@keyframes track {
  100% {
    left: -200px;
  }
}