- /* header is 38px + 1px border, slidenav is 13px + 4px + 30px paddings,
- another 5px for safety */
- height: calc(100% - 90px);
+ /* header is 40px, 7px to have a bit of distance,
+ * 3px height-reducing on the bottom for safety */
+ top: 47px;
+ height: calc(100% - 50px);