css 锥形渐变实现三角探照灯效果

锥形渐变实现探照灯,通过元素覆盖在上面并设置透明度,实现取出探照灯的效果

效果图:


原理:

代码示例:

.conic {
    
    
    position: relative;
    z-index: 0;
    width: 400px;
    height: 300px;
    margin: 20px;
    border-radius: 10px;
    //隐藏探照灯其他区域
    overflow: hidden;
    padding: 2rem;
    
}

//探照灯的实现
.conic::before {
    
    
    content: '';
    position: absolute;
    left: -50%;
    top: -50%;
    width: 200%;
    height: 200%;
    background-color: green;
    background-repeat: no-repeat;
    background-position: 0 0;
    background-image: conic-gradient(transparent, rgba(168, 239, 255, 1), transparent 30%);
    animation: rotate 4s linear infinite;
}

//通过透明度使得探照灯上的元素能看见探照灯
.conic::after {
    
    
    content: '';
    position: absolute;
    z-index: -1;
    left: 6px;
    top: 6px;
    width: calc(100% - 12px);
    height: calc(100% - 12px);
    background: red;
    border-radius: 5px;
    opacity: .5;
}

@keyframes rotate {
    
    
    100% {
    
    
        transform: rotate(1turn);
    }
}

<div class="conic"></div>