需求：一个p设置了background: url，现在需要使图片背景模糊，p内的文字清晰显示。

.content {            color: #ffffff;            font-size: 40px;        }
 .bg {            background: url('1.jpg');            height:600px;            text-align: center;            line-height: 600px;        }
.bg-blur {            float: left;            width: 100%;            background-repeat: no-repeat;            background-position: center;            background-size: cover;            -webkit-filter: blur(15px);            -moz-filter: blur(15px);            -o-filter: blur(15px);            -ms-filter: blur(15px);            filter: blur(15px);        }
.content-front {          position:absolute;          left: 10px;          right: 10px;          height:600px;          line-height: 600px;          text-align: center;        }