*{
    padding: 0;
    margin: 0;
    box-sizing: border-box;
}

input[type="checkbox"] {
    appearance: none;
    width: 16px;
    height: 16px;
    border:1px solid #ccc;
    border-radius: 4px;
    cursor: pointer;
    position: relative;
    background-color: #fff;
  }
  
 input[type="checkbox"]:checked {
    background-color: #007F73; 
    border-color: #007F73;
  }
  
 input[type="checkbox"]:checked::after {
    content: "";
    position: absolute;
    top: 2px;
    left: 6px;
    width: 4px;
    height: 8px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
  }

  .scroll-parent {
    height: 900px;
    overflow: hidden;
}

.topbottom {
    display: flex;
    width: 40%;
    flex-direction: column;
    animation: scroll-vertical 30s linear infinite;
    
}

.bottomtop {
    display: flex;
    width: 40%;
    flex-direction: column;
    transition: all 30s ease;
    animation: scroll-vertical-bottom 30s linear infinite;
    
}

.topbottom img{
    box-shadow: 0 0 20px #999;
    border-radius: 5px !important;
}

.bottomtop img{
    box-shadow: 0 0 20px #999;
    border-radius: 5px !important;
}

@keyframes scroll-vertical {
    0% {
        transform: translateY(-50%);
    }
    100% {
        transform: translateY(0);
    }
}

@keyframes scroll-vertical-bottom {
    0% {
        transform: translateY(0);
    }
    100% {
        transform: translateY(-50%);
    }
}