CSSで戦車を作ってみた。

実際の動きはこちらで確認できます
https://jsfiddle.net/junya_5102/th133o9g/7/

html

<div class="tank-wrap medium green">
  <div class="tank">
    <div class="turret">
      <div class="gun"></div>
      <div class="sub-gun"></div>
      <div class="antenna"></div>
    </div>
    <div class="body"></div>
    <div class="crawler">
      <div class="roller"></div>
      <div class="roller"></div>
      <div class="roller"></div>
      <div class="roller"></div>
      <div class="roller"></div>
      <div class="roller"></div>
      <div class="roller"></div>
    </div>
  </div>
</div>

CSS

.tank-wrap{
  position: relative;
  width: 300px;
  height: 120px;
  padding-top: 10px;
  padding-right: 10px;
  padding-left: 100px;
}

.tank{
  position: relative;
  -webkit-perspective: 500px;
}

/* 砲塔 */
.tank .turret{
  position: relative;
  top: 15px;
  left: 60px;
  width: 180px;
  height: 40px;
  border-radius: 60% 0 0 80% / 100% 0 0 100%; 
  background: currentColor;
  box-shadow: 10px 5px 0 0 currentColor;
}

.tank .turret:before{
  position: absolute;
  top: 10px;
  right: -30px;
  content: "";
  width: 50px;
  height: 50%;
  background: currentColor;
  box-shadow: -5px 0 0 0 currentColor;
}

/*　砲　*/
.tank .turret .gun{
  position: absolute;
  top: 15px;
  left: -50px;
  width: 90px;
  height: 10px;
  border-radius: 40% 0 0 40%;
  background: currentColor;
}

.tank .turret .gun:before{
  position: absolute;
  top: 1px;
  left: -80px;
  content: "";
  display: inline-block;
  width: 90px;
  height: 8px;
  border-radius: 40% 0 0 40%;
  background: inherit;
}

/* 機銃 */
.tank .turret .sub-gun{
  position: absolute;
  top: -10px;
  left: 50px;
  width: 25px;
  height: 8px;
  border-radius: 50% 80% 0 50% / 100% 100% 0 100%;
  background: currentColor;
}

.tank .turret .sub-gun:before,
.tank .turret .sub-gun:after{
  position: absolute;
  content: "";
  display: inline-block;
  background: inherit;
}

.tank .turret .sub-gun:before{
  top: 3px;
  left:  -30px;
  width: 40px;
  height: 3px;
  border-radius: 50% 0 0 50% / 100% 0 0 100%;
}

.tank .turret .sub-gun:after{
  left: 10px;
  width: 8px;
  height: 30px;
}

/* アンテナ */
.tank .turret .antenna{
  position: absolute;
  right: -20px;
  width: 50px;
  height: 1px;
  background: #000;
  transform: rotate(120deg);
}

/* 車体 */
.tank .body{
  position: relative;
  top: 10px;
  width: 300px;
  height: 40px;
  border-radius: 40% 0 0 0 ;
  background: currentColor;
  z-index: 2;
}

/* 履帯全体 */
.tank .crawler{
  position: relative;
  left: 0;
  width: 290px;
  height: 35px;
  border-right: 5px dotted #4F3E37;
  border-left: 5px dotted #4F3E37;
  border-radius: 0 0 30% 30% / 0 0 100% 100%;
  background: #052224;
  z-index: 1;
  overflow: hidden;
  box-sizing: border-box;
}

/* 履帯 */
.tank .crawler:before{
  position: absolute;
  bottom: 1px;
  left: -100%;
  content: "";
  width: 300%;
  height:100px;
  border-bottom: 5px dotted #4F3E37;
  background: #052224;
}

/* 転輪 */
.tank .crawler .roller{
  position: absolute;
  display: inline-block;
  width: 30px;
  height: 30px;
  border: 2px dotted white;
  border-radius: 100%;
  background: #264345;
  box-sizing: border-box;
}

.tank .crawler .roller:nth-child(1){
  top: -15px;
  left: 0px;
}

.tank .crawler .roller:nth-child(2){
  top: -2px;
  left: 30px;
}

.tank .crawler .roller:nth-child(3){
  left: 80px;
}

.tank .crawler .roller:nth-child(4){
  left: 130px;
}

.tank .crawler .roller:nth-child(5){
  left: 180px;
}

.tank .crawler .roller:nth-child(6){
  top: -3px;
  left: 220px;
}

.tank .crawler .roller:nth-child(7){
  top: -15px;
  left: 250px;
}

/* 色 */
.green{
  color: #264345;
}

/* 大きさ */
.medium{
  transform: scale(1);
}

.small{
  transform: scale(.5);
}

/* アニメーション */
.tank{
  animation: tank_anim 1s ease-in-out infinite;
}

.tank .turret{
  animation: turret_anim 5s ease-in-out infinite alternate;
}

.tank .crawler:before{
  animation: crawler_anim 5s linear infinite;
}

.tank .crawler .roller{
  animation: roller_anim 3s linear infinite;
}

/* 戦車の揺れ */
@keyframes tank_anim{
  0%{
    transform-origin: center center;
  }
  25%{
    transform-origin: left center;
    transform: rotate(.12deg);
  }

  75%{
    transform-origin: right center;
    transform: rotate(.12deg);
  }
}

/* 砲塔回転 */
@keyframes turret_anim{
  100%{
    transform: rotateY(25deg);
  }
}

/* 転輪回転 */
@keyframes roller_anim{
  100%{
    transform: rotate(-360deg);
  }
}

/* 履帯(キャタピラ)回転 */
@keyframes crawler_anim{
  100%{
    transform: translateX(100px);
  }
}

border-radius: 水平方向の径 / 垂直方向の径;
/で区切ることで個別に指定できる