Web Background ( Aquarium )

document.body.style.cssText = 'background: url("https://31.media.tumblr.com/8d0c81c7f8197780f267edb89be3c71c/tumblr_n2898tzRKj1rlaql2o1_500.gif") no-repeat center center fixed; background-size: cover; opacity: 0.9;';