In out posts we use 60% content width for ease of reading. However, when the window is narrowed to a tablet width, the test becomes too narrow for comfort. And when narrowed to phone width it becomes an unreadable central strip. How can I set different text widths on narrow screens (for example – 60% desktop, 75% laptop, 90% phone). Or just 60% down to a screen width and 90% or 100% below that width?