<div class="hover__wrap">
  <div class="hover__updown">
    <figure class="front">
      <img src="https://github.com/Youcodein/coding2/blob/main/assets/img/anime_bg_1.jpg?raw=true" alt="">
      <figcaption>
        <h3>Mouse Hover Effect</h3>
        <p>마우스 올리면 UP</p>
      </figcaption>
    </figure>
    <figure class="back">
        <img src="https://github.com/Youcodein/coding2/blob/main/assets/img/anime_bg_2.jpg?raw=true" alt="">
        <figcaption>
          <h3>Mouse Hover Effect</h3>
          <p>마우스 내리면 DOWN</p>
        </figcaption>
    </figure>
  </div>
  <div class="hover__leftright">
        <figure class="front">
      <img src="https://github.com/Youcodein/coding2/blob/main/assets/img/anime_bg_3.jpg?raw=true" alt="">
      <figcaption>
        <h3>Mouse Hover Effect</h3>
        <p>마우스 올리면 to LEFT</p>
      </figcaption>
    </figure>
    <figure class="back">
        <img src="https://github.com/Youcodein/coding2/blob/main/assets/img/anime_bg_4.jpg?raw=true" alt="">
        <figcaption>
          <h3>Mouse Hover Effect</h3>
          <p>마우스 내리면 to RIGHT</p>
        </figcaption>
    </figure>
  </div>
</div>

@font-face {
    font-family: 'LocusSangsang';
    font-weight: normal;
    font-style: normal;
    src: url('https://cdn.jsdelivr.net/gh/webfontworld/locus/LocusSangsang.eot');
    src: url('https://cdn.jsdelivr.net/gh/webfontworld/locus/LocusSangsang.eot?#iefix') format('embedded-opentype'),
         url('https://cdn.jsdelivr.net/gh/webfontworld/locus/LocusSangsang.woff2') format('woff2'),
         url('https://cdn.jsdelivr.net/gh/webfontworld/locus/LocusSangsang.woff') format('woff'),
         url('https://cdn.jsdelivr.net/gh/webfontworld/locus/LocusSangsang.ttf') format("truetype");
    font-display: swap;
}

body {
  font-family: ‘LocusSangsang’;
  background-image: linear-gradient(135deg, #191970 0%, #483088 40%, #0370DB 100%);
  height: 100vh;
}
.hover__wrap {
  display: flex;
  justify-content:center;
  align-items: center;
  height: 100vh;
}
.hover__wrap > div  {
  max-width: 400px;
  margin: 3%;
  position: relative;
/*  원근감을 주는 것  3d 공간의 깊이를 표현 : 값이 낮을 수록 원근효과 ↑ */
  perspective: 1000px;
}
.hover__wrap > div img {
  width: 100%;
  border: 5px solid #F0F8FF;
  box-shadow: 2px 2px 2px 2px rgba(0,0,0,0.2);
  box-sizing: border-box;
  vertical-align: top;
}
.hover__wrap > div .front {
  transition: transform 1s;
  backface-visibility: hidden;
  transform-style: preserve-3d;
}
.hover__wrap > div .back {
  position: absolute;
  left: 0;
  top: 0;
  z-index: -1;
  transition: transform 1s;
/* 기본 값은 "flat"로, 자식 요소는 2D의 2차원에서 부모 요소와 동일한 평면에 배치되지만, "transform-style : preserve-3d;"을 지정하여 3D 공간에 배치되도록 함. */
  transform-style: preserve-3d;
  
}
.hover__wrap > div figcaption {
  background: rgba(0,0,0,0.4);
  color: #F8F8FF;
  padding: 10px;
  text-align: center;
  line-height: 1.5;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%) translatez(100px);
  width: 60%;
/*  backface-visibility는 요소의 뒷쪽에서 앞면이 보이게 할지 정하는 속성  */
  backface-visibility: hidden;
}
/* mouse hover effect */
/* X축을 기준으로 반전 효과 rotateX */
/* Y축을 기준으로 반전 효과 rotateY */
.hover__updown .front {
  transform: rotateX(0deg);
}
.hover__updown:hover .front {
  transform: rotateX(180deg);
}
.hover__updown .back {
  transform: rotateX(-180deg);
}
.hover__updown:hover .back {
  transform: rotateX(0deg);
}
.hover__leftright .front {
  transform: rotateY(0deg);
}
.hover__leftright:hover .front {
  transform: rotateY(180deg);
}
.hover__leftright .back {
  transform: rotateY(-180deg);
}
.hover__leftright:hover .back {
  transform: rotateY(0deg);
}