preloader style : demo 269

                        .loader{
                            width: 150px;
                            height: 150px;
                            margin: 0 auto;
                            overflow: hidden;
                            position: relative;
                        }
                        .loader:before,
                        .loader:after{
                            content: '';
                            background: linear-gradient(#38ef7d,#11998e);
                            width: 100%;
                            height: 100%;
                            position: absolute;
                            top: 0;
                            left: 0;
                            animation: rotate 5s infinite alternate;
                        }
                        .loader:after{
                            background: #fff;
                            width: 80%;
                            height: 80%;
                            transform: translateX(-50%) translateY(-50%);
                            top: 50%;
                            left: 50%;
                            animation: none;
                        }
                        .loader .inner_loader{
                            background: linear-gradient(#38ef7d,#11998e);
                            position: absolute;
                            height: 50%;
                            width: 50%;
                            transform: translateX(-50%) translateY(-50%);
                            top: 50%;
                            left: 50%;
                            z-index: 1;
                            animation: 5s rotate_1 infinite alternate;
                        }
                        @keyframes rotate{
                            0%{ transform: rotate(180deg); }
                            50%{ transform: rotate(360deg); }
                        }
                        @keyframes rotate_1{
                            0%{ transform:translateX(-50%) translateY(-50%) rotate(180deg); }
                            50%{ transform:translateX(-50%) translateY(-50%) rotate(360deg); }
                        }