The default grid system provided in Bootstrap utilizes 12 columns that render out at widths of 724px, 940px (default without responsive CSS included), and 1170px. Below 767px viewports, the columns become fluid and stack vertically.
但是换个角度，从在社会事件中对错误舆论进行正向引导、斧正的角色来看，知乎平台也具备其他平台力所不及的能力。而杂乱的UI界面最常见的原因，就是缺少层次结构。