Offers highlighted in reddish color indicate offers that have been halted, but you are still pushing. Offers highlighted in yellowish color indicate offers that have reached the daily CAP.
Besides emailing to you newsletters and notifications about the status of offers, color highlighting of offers is another measure to draw your attention and help you detect cases for which action needs to be taken on your side, e.g. stop pushing halted offers or temporarily pause pushing offers until the next day.