margin-collapse-clear-012

Margin collapsing with clearance - margins of a 'collapsed through' box with clearance do not collapse with parent block's bottom margin

WeasyPrint

This browser

Assertion
When an element has had clearance applied to it and its own margins collapse, these margins collapse with the adjoining margins of following siblings but the resulting margin does not collapse with the bottom margin of the parent block

Source

  1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
  2 <html>
  3 
  4  <head>
  5 
  6   <title>CSS Test: Margin collapsing with clearance - margins of a 'collapsed through' box with clearance do not collapse with parent block's bottom margin</title>
  7 
  8   <link rel="help" href="http://www.w3.org/TR/CSS21/box.html#collapsing-margins">
  9   <link rel="help" href="http://www.w3.org/TR/CSS21/visudet.html#normal-block">
 10   <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
 11   <link rel="author" title="Bruno Fassino" href="fassino[at]gmail.com">
 12   <meta content="When an element has had clearance applied to it and its own margins collapse, these margins collapse with the adjoining margins of following siblings but the resulting margin does not collapse with the bottom margin of the parent block" name="assert">
 13   <meta content="" name="flags">
 14 
 15   <style type="text/css">
 16   #relatively-positioned-wrapper
 17   {
 18   position: relative;
 19   }
 20 
 21   #parent-lime
 22   {
 23   background-color: lime;
 24   border-top: black solid 1px;
 25   width: 50%;
 26   }
 27 
 28   #float-left-blue
 29   {
 30   background-color: blue;
 31   float: left;
 32   height: 100px;
 33   width: 100px;
 34   }
 35 
 36   #clear-left
 37   {
 38   clear: left;
 39   margin-bottom: 80px;
 40   margin-top: 40px;
 41   }
 42 
 43   #sole-following-sibling
 44   {
 45   margin-bottom: 140px;
 46   }
 47 
 48   #next-yellow
 49   {
 50   background-color: yellow;
 51   height: 100px;
 52   }
 53 
 54   .ref-overlapped-red
 55   {
 56   background-color: red;
 57   position: absolute;
 58   z-index: -1;
 59   }
 60 
 61   #ref1
 62   {
 63   height: 200px;
 64   top: 1px;
 65   width: 50%;
 66   }
 67 
 68   #ref2
 69   {
 70   height: 100px;
 71   top: 201px;
 72   width: 100%;
 73   }
 74   </style>
 75 
 76  </head>
 77 
 78  <body>
 79 
 80   <p>Test passes if there is no red visible on the page.</p>
 81 
 82   <div id="relatively-positioned-wrapper">
 83 
 84   <!--
 85   #parent-lime should have height 200px, sum of:
 86   height of #float-left-blue (100px)
 87   part of #sole-following-sibling's margin-bottom "exceeding" the amount collapsed with #clear-left's margin-top (140px - 40px)
 88   -->
 89 
 90    <div id="parent-lime">
 91     <div id="float-left-blue"></div>
 92     <div id="clear-left"></div>
 93     <!-- clearance + margin-top of #clear-left = height of #float-left-blue; therefore, clearance is equal to +60px -->
 94     <div id="sole-following-sibling"></div>
 95    </div>
 96 
 97    <div id="next-yellow"></div>
 98 
 99    <!--
100    #ref1 and #ref2 boxes create a sort of 'reference rendering' where #ref1 should be covered, overlapped by #parent-lime while #ref2 should be covered, overlapped by #next-yellow.
101    -->
102 
103    <div id="ref1" class="ref-overlapped-red"></div>
104    <div id="ref2" class="ref-overlapped-red"></div>
105 
106   </div>
107 
108  </body>
109 </html>