style.css

body {
  margin: 0;
  padding: 0;
  font-size: 16px;
  font-family: sans-serif;
  color: #333;
}

.board,
.board__inner-column {
  list-style-type: none;
  padding-left: 0;
  margin: 0;
}

.board {
  align-items: stretch;
  display: flex;
  flex-direction: row;
  height: 100vh;
  justify-content: flex-start;
}

.board__column {
  background-color: #eee;
  min-width: 250px;
  margin: 10px;
  border-radius: 4px;
}

.board__column-name {
  color: #5e6c84;
  font-weight: 500;
  text-transform: uppercase;
  padding: 16px 12px 0;
  font-size: 12px;
  display: inline-block;
}

.board__inner-column {
  padding: 10px;
}

.board__card {
  background-color: #fff;
  border: 1px solid #ccc;
  border-radius: 4px;
  padding: 20px;
  user-select: none;
}

.board__card--moving {
  border: 1px solid #5bc0eb;
}

.board__card--active {
  background-color: #fdf19d;
}

.board__card:hover {
  cursor: move;
}

.board__card:not(:last-child) {
  margin-bottom: 20px;
}