HTML Styles Go to the sd_effects.css file in your editor. Andrew wants you to create a fixed background for the browser window. Within the HTML Styles section, insert a style rule for the html element to display the sd_back1.png file as the background image with a width of 100% covering the entire browser window. Have the background image fixed so that it does not scroll with the browser window. Body Styles Andrew wants the web page body background to combine several images and effects. Go to the Body Styles section and create a style rule for the body element that adds the following backgrounds in the order listed: A background containing the night sky image, sd_ back2.png A radial gradient circle with a size extending to the closest corner and placed at the coordinates (40%, 70%) containing the color white stopping at 1 5% of the gradient and the color value rgba(151 , 1 51, 1 51, 0.5) stopping at 50% A radial gradient circle also extending to the closest corner and placed at (80%, 40%) containing the color white stopping at 15% and followed by the color rgba(0, 0, 0, 0) at 30% A radial gradient extending to the closest side and placed at (10%, 20%) containing the color white stopping at 20% and followed by the color rgba(0, 0, 0, 0) stopping at 45% A radial gradient with a size of 5% in the horizontal and vertical directions placed at (90%, 10%) with the color white stopping at 1 5% and followed by the color rgba(0, 0, 0, 0) stopping at 40% The background color rgb(151, 151, 151) set as a base for the preceding background image . Within the style rule for the page body, add styles to place box shadows on the left and right borders. Set the color of the first shadow to rgb(31, 31, 31) with horizontal and vertical offsets of 30 pixels and 0 pixels and a blur of 45 pixels. Set the second shadow equal to the first except that the horizontal offset should be -30 pixels