Articles not rendering mobile friendly

Several articles on website are not rendering on mobile devices. As example: gatekeepersolutions.com/index.php?option=com_content&view=article&id=245%245A5-advantages-of-time-&-attendance=automation&catid=6%253Aarticles&Itemid=77. Please help

Most likely it's because of you use <table> with hardcoded size (991x297px) that breaks default mobile viewport width of 320px. Either use relative sizes, or create separate content for mobile devices using Mobile Content plugin.