Checkbox style : demo 20

                        .checkbox{ display: inline-block; }
                        .checkbox input[type=checkbox]{
                            margin: 0;
                            visibility: hidden;
                            left: 1px;
                            top: 1px;
                        }
                        .checkbox label{
                            width: 20px;
                            height: 40px;
                            border: 2px solid #706d92;
                            cursor: pointer;
                            border-radius: 100px;
                            overflow: hidden;
                            display: block;
                            position: relative;
                            z-index: 1;
                            transition: all 0.3s ease;
                        }
                        .checkbox label:before{
                            content: '';
                            background: #706d92;
                            border-radius: 50px;
                            width: 16px;
                            height: 16px;
                            transform: translateX(-50%);
                            position: absolute;
                            bottom: 2px;
                            left: 50%;
                            transition: all 0.3s ease;
                        }
                        .checkbox input[type=checkbox]:checked+label{
                            background: #7338ba;
                            border: 2px solid #7338ba;
                        }
                        .checkbox input[type=checkbox]:checked+label:before{
                            background: #fff;
                            bottom: 18px;
                        }
                        @media only screen and (max-width:767px){
                            .checkbox{ margin: 0 0 20px; }
                        }