*{
    padding: 0;
    margin: 0;
    box-sizing: border-box;
    font-family: sans-serif;
}
body{
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    background-color: #121212;
    overflow: hidden;
}
/*以下是方舟反應爐的程式*/
.loader{
    position: relative;
    width: 300px;
    height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.loader_back{
    position: absolute;
    width: 300px;
    height: 300px;
    /* 原來 8px */
    border: dashed 16px #00ffe7;
    border-radius: 50%;
    z-index: 3;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: spin 5s infinite reverse;
}
/* 內圈 */
.loader_back:before{
    position: absolute;
    content: '';
    width: 96%;
    height: 96%;
    border: dashed 8px #00ffe7;
    border-radius: 50%;
    z-index: 3;
    animation: spin 4s infinite;
}
.loader_blur{
    position: absolute;
    width: 115%;
    height: 115%;
    border-radius: 50%;
    background-color: #00ffe7;
    opacity: 0.4;
    filter: blur(50px);
    z-index: 4;
}
.loader_black-item{
    position: absolute;
    width: 82%;
    height: 82%;
    border: solid 8px #00ffe7;
    border-radius: 50%;
    border-left-color: transparent;
    z-index: 3;
    opacity: 0.2;
    animation: spin 5s infinite reverse;
}
.loader_black-item:nth-child(3){
    width: 55%;
    height: 55%;
    border-right-color: transparent;
    opacity: 0.6;
    animation: spin 3s ease infinite reverse;
}
.loader_front{
    position: absolute;
    /* 原來46 */
    width: 38%;
    /* 原來46 */
    height: 38%;
    border-radius: 50%;
    background-color: #befff9;
    z-index: 5;
    display: flex;
    align-items: center;
    justify-content: center;
}
.loader_front:before{
    position: absolute;
    content: '';
    width: 90%;
    height: 90%;
    border-radius: 50%;
    background-color: #fff;
    z-index: 5;
}
.loader_front-item{
    position: absolute;
    width: 150%;
    height: 150%;
    border: solid 8px #00ffe7;
    border-radius: 50%;
    border-top-color: transparent;
    border-bottom-color: transparent;
    z-index: 5;
    animation: spin 2s infinite;
}
@keyframes spin{
    100%{
        transform: rotate(360deg);
    }
}