*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html,body{
  display: grid;
  height: 100%;
  place-items: center;
  background: #f2eee3;
}
.wrapper{
  position: relative;
  height: 512px;
  width: 512px;
  overflow: hidden;
  background: #fff;
  border: 7px solid #fff;
  box-shadow: 0px 0px 15px rgba(0,0,0,0.15);
}
.wrapper .images{
  height: 100%;
  width: 100%;
  display: flex;
}
.wrapper .images .img-1{
  height: 100%;
  width: 100%;
  background: url("images/normal.png") no-repeat;
  
}
.wrapper .images .img-2{
  position: absolute;
  height: 100%;
  width: 50%;
  background: url("images/modificada.jpg") no-repeat;
}
.wrapper .slider{
  position: absolute;
  top: 0;
  width: 100%;
  z-index: 99;
}
.wrapper .slider input{
  width: 100%;
  outline: none;
  background: none;
  -webkit-appearance: none;
}
.slider input::-webkit-slider-thumb{
  height: 486px;
  width: 3px;
  background: none;
  -webkit-appearance: none;
  cursor: col-resize;
}
.slider .drag-line{
  width: 3px;
  height: 486px;
  position: absolute;
  left: 49.85%;
  pointer-events: none;
}
.slider .drag-line::before,
.slider .drag-line::after{
  position: absolute;
  content: "";
  width: 100%;
  height: 222px;
  background: #fff;
}
.slider .drag-line::before{
  top: 0;
}
.slider .drag-line::after{
  bottom: 0;
}
.slider .drag-line span{
  height: 42px;
  width: 42px;
  border: 3px solid #fff;
  position: absolute;
  top: 50%;
  left: 50%;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}
.slider .drag-line span::before,
.slider .drag-line span::after{
  position: absolute;
  content: "";
  top: 50%;
  border: 10px solid transparent;
  border-bottom-width: 0px;
  border-right-width: 0px;
  transform: translate(-50%, -50%) rotate(45deg);
}
.slider .drag-line span::before{
  left: 40%;
  border-left-color: #fff;
}
.slider .drag-line span::after{
  left: 60%;
  border-top-color: #fff;
}