One query, many elements
Level 9 of 10Your goal
At viewports 600px and wider, make the header 400px, the sidebar 300px and main 400px wide. Below that, all three stay 200px. Heights don't change.
Checked at 2 stage widths (420px, 700px) — every stage below has to match.
Elements
Hover one to find it on the stage. Click it, or put your cursor inside its CSS rule, to focus on just that element.
stage 420px
stage 700px
target content boxtarget outer edge (green = matched, red = not yet)your element (hovered or focused)
Feedback updates as you type, and your CSS is saved in this browser. Exact target numbers are in the Target panel.