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Source Sans is a free Open Source Google font, and is a close visual match to Din, MIT's brand font. Because we wanted to be able to make the system of applications Open Source products, we chose Source Sans instead of Din, which is a licensed font.
Use Source Sans everywhere within the content, headers, interior content, and containers.
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Forms should be designed in accordance with the standards above. All fields should include field labels. Labels appear above their fields left aligned with the beginning of the field (except in cases of very long forms i.e., more than 1 full page of scrolling; in this case, labels can appear to the left, aligned left). Buttons should appear at the bottoms of the forms, left aligned with the form fields (not the field labels). 
2.5.1 Form fields
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