* {
    margin: 0px;
    padding: 0px;
  }
  body {
    justify-content: center;
    align-items: center;
    display: flex;
    min-height: 100vh;
    
  }
  .main {
    height: 400px;
    width: 400px;
    display: grid;
    background-color: rgb(226, 43, 43);
    grid-column-gap: 0;
    grid-template-rows: repeat(20, 1fr);
    grid-template-columns: repeat(20, 1fr);
  }
  .box {
    border: solid 1px rgba(0, 0, 0, 0.281);
    padding: 2px;
  }
  .chgclr {
    background: #fff;
    
}