Ah, now I see what you are referring to. Turns out it’s my fault because I left the background in the style.css, which should not be there. I will make this as an update to remove that, but in the mean time, you can change this in the parent theme of Preference style.css file around line 81
body {
font-size:13px;
font-size: 0.813rem;
line-height:21px;
line-height:1.313rem;
background: #dadddf url('images/patterns/pattern-bg.png') 0 0 repeat fixed;
}
Remove the background line of css code. The new update later will reflect this.
I thought you were referring to the Celestial theme, but this solution is for the Preference one.