• as clear as day, crystal clear
• I don't quite get the idea
• get the message?, get the picture?
• clear, clearly, distinctly, explicitly, legibly, lucidly, patently, plainly, unequivocally
• Cambridge blue, pale blue
• brightness, brilliance, brilliancy, clarity, distinctness, light, limpidity, lucidity, neatness, perspicuity
• it is clear that, that is easy to see