.table {
    border-collapse: collapse;
}
.table,
.table th,
.table td {
    border: 1px solid #e7e7e7;
    margin: 0px;
}
.table th,
.table td {
    padding: 0.5rem;
}
.table th {
    position: relative;
}
.resizer {
    position: absolute;
    top: 0;
    right: 0;
    width: 5px;
    cursor: col-resize;
    user-select: none;
}
.resizer:hover,
.resizing {
    border-right: 2px solid blue;
}

.resizable {
    border: 1px solid gray;
    height: 100px;
    width: 100px;
    position: relative;
}