Responsive layout dashboard
Overview — 100% width × 25% viewport height
50% width × 25% height
50% width × 25% height
Chart — 67% wide × 50% height
Width: 8 of 12 columns = 67%  |  Height: 2 of 4 rows = 50%
Sidebar — 33% wide × 50% height
Width: 4 of 12 columns = 33%  |  Height: 2 of 4 rows = 50%