The default jasmine page always jumped around, since the #jasmine_content area is above the results.
This css makes the page more stable with a 2-column layout, progress top, results left, content right.

# jasmine.yml
stylesheets:
  - spec/javascripts/support/jasmine.css
  ...

# spec/javascripts/support/jasmine.css

#HTMLReporter .results{
  position:absolute;
  top: 250px;
  width: 50%;
}

#jasmine_content {
  position:absolute;
  top: 250px;
  right: 0;
  width: 50%;
}