Modifying textarea background color in ckeditor

Question

Where to modify ckeditor textarea background color (same color as we get using in <pre> tag) as default color?


Where(css page?) to modify and what code should be there? 

Could you please explain. Thanks in advance.

I am trying to use `special container` style but this color is not as same as <pre> tag (know color code in pre tag?), also this style has border line which is not looking better.

Comments

Should I edit this code? : qa-plugin/mathjax-master/custom.css:

.entry-content,.qa-q-view-content,.qa-a-item-content,.qa-c-item-content{
font-size: 16px;
overflow:auto;
    padding-top: 10px;
    padding-left: 10px;
    padding-right: 10px;
padding-bottom: 20px;
    background: #f5f5f5;
font-family: georgia,serif;
}
.qa-c-item-content {
    font-size: 14px;
}

But seems already fine, then why not reflecting it?

---

Code fine but this should be on qa-theme/Donut-theme/css/donut.min.css , see https://www.question2answer.org/qa/72162/content-formatting-for-question-and-answers