Initially it was like this:
Although in the "content" to make two blocks, I added one more (8)
Block (4) moved down. But yes, grid 12 (8 and 4 slid down) everything is fine, because adding 8 I created a new grid.
How do I divide unit 8 into 2 parts? Like this: 
Notes: Option with creating a new grid, type:
Old grid: 8 and 4 New grid: 8
Does not fit. It is only necessary to use 1 grid, in which the 1st block (8) needs to be divided.
<main class="mdl-layout__content mdl-color--grey-100"> <div class="mdl-grid ali-content"> <div class="ali-graphs mdl-shadow--2dp mdl-color--white mdl-color-text--grey-500 mdl-cell mdl-cell--8-col">............</div> <div class="ali-cards mdl-cell mdl-cell--4-col mdl-cell--8-col-tablet mdl-grid mdl-grid--no-spacing"> <div class="ali-updates mdl-card mdl-shadow--2dp mdl-cell mdl-cell--4-col mdl-cell--4-col-tablet mdl-cell--12-col-desktop"> <div class="mdl-card__title">.......</div> <div class="mdl-card__actions mdl-card--border">........</div> </div> <div class="ali-separator mdl-cell--1-col"></div> </div> </div> </main> 
