Project: stylus
Task (easy): In design page, a Question title is clicked to edit (contenteditable=true) in place. In preview page, title can not be edited. Append 'Question.root' with a config panel (class 'q-config') containing a button (class 'q-remove') clicked to remove the question from the form. Config panel should be hidden in preview page. Extract all colors to stylus nested variable '$color', all padding/margin value to stylus variables (using computed value) and all border properties to mixins. Use stylus functions to handle similar colors, e.g. lighter or darker colors. Save these variables and mixins to 'common/config.styl' which should be imported by 'common.styl'.