The doctype of the html file is changed from Transitional to Strict, and a large space is left between the divs_html/css_WEB-ITnose

css

Modify a project previously developed by others, which is an asp.net web project.
The doctype of the originally developed HTML file was Transitional, and the images were normal.
Now we need to uniformly change to the doctype of standard HTML: Strict.

After the modification, the screen was messed up. After various adjustments and calculations to modify the css properties, finally part of the screen could be consistent with the original display effect.

However, some parts of the screen use the original usercontrol, and no matter how you adjust it, there will be a large white space with the original screen.
Delete all redundant HTML controls and find that the positions are determined by table and div. No matter how much I change, I can't adjust it well.

Please help me find out what css attribute may be causing the large white space between divs on the screen.
Thank you.

Reply to the discussion (solution)

Generally, you can use Transitional or use ,
There is no code, so it’s hard to say what the problem is, but You can refer to
Transitional vs. Strict tag differences
http://24ways.org/2005/transitional-vs-strict-markup/


Quirks mode and strict mode
http://www.quirksmode.org/css/quirksmode.html