system.plugin.ui.css 

#block-library .left-col,
#block-library .right-col {
  float:left;
  width:66%;
  height:100%;
  background-color:#ffffff;
}

#block-library .right-col {
  width:34%;
  background-color:#f7f7f7;
}

#block-library .right-col h3 {
  margin: 1em -20px;
  background-color:#d7d7d7;
  color:#333333;
  padding:8px 15px;
  font-size:1.1em;
}

#block-library .inside {
  margin:0 20px;
}

#block-library .bottom-bar {
  width:100%;
  clear:both;
}

File

drupal/core/modules/system/css/system.plugin.ui.css
View source
  1. #block-library .left-col,

  2. #block-library .right-col {

  3.   float:left;

  4.   width:66%;

  5.   height:100%;

  6.   background-color:#ffffff;

  7. }

  8. 

  9. #block-library .right-col {

  10.   width:34%;

  11.   background-color:#f7f7f7;

  12. }

  13. 

  14. #block-library .right-col h3 {

  15.   margin: 1em -20px;

  16.   background-color:#d7d7d7;

  17.   color:#333333;

  18.   padding:8px 15px;

  19.   font-size:1.1em;

  20. }

  21. 

  22. #block-library .inside {

  23.   margin:0 20px;

  24. }

  25. 

  26. #block-library .bottom-bar {

  27.   width:100%;

  28.   clear:both;

  29. }