@import 'https://www.calculators.org/learn/wp-content/themes/peekaboo/css/styleall.css';

body {
  background: url(../img/bgmath.jpg) no-repeat center center fixed;
   opacity: 0.99;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}